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In an urbanization process, infrastructure elements such as tunnels and deep excavations are widely used to service the development of cities. Owing to the lengthy geological processes of geomaterials and the limited availability of site-specific test data, soil and rock properties exhibiting spatial variability are frequently encountered in geological and geotechnical engineering. This paper presents a comprehensive review of the application of spatial variability in tunneling and deep excavation over the past 20 years. It is found that the spatial variability is generally modeled as a random field (RF) in finite element software, based on random field theory (RFT). This model has been widely used in the design, stability evaluation, and probabilistic analysis of tunnels and excavations. Previous works have proven that the performance of tunnels and deep excavations can be better captured by considering the spatial variability, as compared with conventional deterministic analysis methods. Nonetheless, current research still faces many factual scientific problems. Therefore, this paper also identifies some research gaps, as well as recommendations for further investigations.

This paper provides an overview of the results obtained from recent (2016–2017) archaeological investigations the Early Bronze age site of Karnut, located in the Shirak province, of northwestern Armenia. The main focus will be on the newly discovered Kura-Araxes burials and dwellings. A preliminary attempt will be made to address issues regarding the dating of the newly discovered materials, as well as to provide a first comparison with the results yielded by former excavations. New elements concerning burial practices at the site will then be discussed in the context of established frameworks of burial rituals as known from formerly investigated burial sites of the Kura-Araxes culture. Ultimately, the issues discussed in this paper highlight important future directions in the research on funerary practices in the Early Bronze Age South Caucasus.

Excavation in highly stressed grounds may lead to violent compressive failures of rock or violent slip along discontinuities in the vicinity of the underground space. Violent failures, usually with anomalous seismic signatures, are characterized with radiating excess energy during the failure, endangering the safety and productivity of the operation. This paper adopts a numerical methodology, developed in the Universal Distinct Element Code (UDEC) for quantitatively studying the occurrence and intensity of violent failures, and advances it for respective analyses in tunneling and shaft-boring operations. The methodology enables estimating the radiated energy as a measure for evaluating the occurrence and relative intensity of violent failures. We first validate the radiated energy calculation in the models against analytical solutions for the formation of a circular opening, analogous to the geometry of tunnels and shafts. After reviewing the concept of violent failures by ideal models, we explore the effects of different factors on the occurrence and intensity of violent failures caused by an excavation into brittle rock or next to a preexisting fault. Limited cases studied in this paper demonstrate that different combinations of the rock elastic modulus and post-failure response of rock and discontinuity can result in a violent failure with various intensities. Larger excavations under higher deviatoric stresses can intensify the potential violent failure mostly through expanding the rock failure zone or the slip area on the activated fault. However, as opposed to the radiated energy, using the failure zone volume and fault slip area alone may lead to underestimating or overestimating the intensity of possible violent failures in a modeling practice. The energy-based analyses outlined in this paper provide a rational yet simple means for quantitatively studying violent failures in potentially complex geological conditions and excavation layouts.

The underground ecological granary has the advantages of low temperature, heat insulation, safety, and mechanization operation of moving grain in and out of the granary. It is the most suitable environmentally friendly warehouse for long-term grain storage at present. Traditional underground granary supporting structures mostly use cement materials and present disadvantages including long periods of construction, difficulties in repairing cracks and leakages, and difficulties in demolition. Based on a steel skeleton supporting structure and flexible waterproof polymers, this paper proposed a new rigid-flexible composite recyclable supporting structure for underground storage granaries. Through the use of ABAQUS software, this paper established a three-dimensional finite element numerical model for excavation of the new supporting structure; analyzed stresses and deformations of the steel pile, middle beam, and steel plate and ground settlement at different excavation steps; and checked the stability of the new supporting structure. Additionally, considering a certain ecological storage granary in Zhongmou County of Henan Province, this paper developed a full-scale test for the new supporting structure. By monitoring the stresses of the supporting structure and ground settlement during excavation, it was concluded that the field monitoring results basically matched the results from numerical simulation. The new supporting structure has the advantages of good stability, quick construction, recyclable usage, low cost, and broad application prospects.

In this short paper, the semi-empirical model introduced by Zheng et al. (2018) for evaluating the tunnel displacements induced by adjacent excavation was extended to a probabilistic model. To this end, the input parameters of the problem were defined as random variables with certain means and standard deviations. A reliability model was then established and solved by the Monte Carlo method. The results showed that the probability of exceedance fell sharply by increasing the tunnel displacement so that the probability of tunnel displacement of larger than 41 mm was less than 5%. Moreover, the reliability sensitivity analysis showed that the excavation depth and tunnel burial depth mostly affected the small range of tunnel displacements between 0.5 and 10 mm. However, the maximum impact of the retaining structure displacement and the horizontal distance of the tunnel from the excavation site were found to fall in medium and large (0.5 to larger than 21 mm) ranges of tunnel displacement. Having the exceedance probability curve presented in this paper, the exceedance probability for any desired value of the tunnel displacement is available, which can be used for safety evaluation and risk assessment of existing tunnels close to the surface excavations.

Tunnelling is the sole means of providing access for transportation, water conveyance in hydropower, mining of minerals, etc. Hydropower alone contributes to about 19% of the commercial energy needs of India and construction of hydroelectric power projects to meet these needs involves huge amounts of tunnelling through varied rock mass conditions. This necessitates identifying methods of tunnelling that are cost-effective, suited to varied geology and yet rapid to commission the projects in place of continuous excavation systems like TBM and Roadheader which are geology sensitive, costly and completely imported thus constraining their smooth adaptation. Mechanized drilling and advanced blasting techniques are the most often used methods of excavation of tunnels in India and in other countries for rapid and cost effective tunnelling, which depends, to a large extent, on the blast performance. Among the outcomes of any blasting operation, pull or advance achieved per blast and blast-induced excavation damage are of major concerns. It is essential to limit the blast-induced damage so as to control time and cost overruns in an underground project more so in varied geology. This paper discusses determination of optimum round lengths of excavation in varied rock classes as well as controlling overbreak in tunnelling. The sequence of excavation, requirements for both top heading and bench are also addressed. It has been observed from the past experiences that round lengths up to 5 m are practiced in rock class I and as the class improves to VII, the pull attempted reduces to about 1 m. Since charging of perimeter holes contributes to overbreak in underground excavations, a thorough analysis of the design of blasting pattern and scheme of charging for minimizing overbreak has been suggested. Characterization of ground through seismic imaging coupled with ground vibration monitoring has been suggested to control blast – induced rock damage and also arrive at optimum charges. As evident in this paper, characterization of the ground is the most important step towards rapid tunnelling.

The Meuse/Haute-Marne Underground Research Laboratory (MHM URL) is an outstanding scientific tool that provides reliable data on the behaviour of Callovo-Oxfordian (COx) claystone. More than 10,000 sensors have been installed in the argillaceous formation to measure rock properties and behaviour under several configurations in order to assess coupled processes. Since 2004, data have been acquired continuously through several measurement campaigns –mainly in galleries at the main level, −490 m (clay unit level –, i.e. UA level), but also in a gallery at −445 m [silty carbonate unit level (USC)]. This experiment has increased understanding of the hydro-mechanical behaviour of claystone and highlight various phenomena. The research program carried out in the MHM URL galleries also is dedicated to technology improvement and demonstration issues of several disposal systems. 1 At MHM URL, the principal horizontal major stress ( σ H ) is oriented at NE150° , and the principal vertical stress ( σ v ) is nearly equal to the principal horizontal minor stress ( σ h ) that is oriented NE065° . The ratio σ H ∕ σ h is close to 1.3 and varies with depth and the rheological characteristics of the respective layers. This paper presents the hydro-mechanical coupling (i.e. interaction between the interstitial water and the solid skeleton) during and after excavation work. The influence of the in-situ stress fields on several types of support was studied for a gallery oriented according to the principal minor horizontal stress ( σ h ). This paper presents an analysis of measurements recorded during and after the construction of an experimental gallery, referred to as the GER, from 2013 to 2015. The GER experimental gallery is an 83-m-long tunnel, in which four different supports were tested: sliding arches; shotcrete; compressible wedges; and poured concrete. Sliding arches, shotcrete and compressible wedges constitute the initial supports that were installed during excavation. The poured concrete was set up about 9 months after the section excavation as a final support, first at the bottom and then at the vault of the gallery. Hydrogeological and geotechnical measurements help to describe the hydro-mechanical response of the surrounding rock mass. Experimental results highlight the anisotropy of the loading from the surrounding rock mass and the influence of the stiffness/flexibility of the support.

Geotechnical stability is a major concern for the long-term safety and integrity of underground infrastructures such as tunnels, railway stations, mine shafts and hydraulic power chambers. An effective geotechnical monitoring system is able to provide adequate warning to underground personnel prior to any unexpected major geotechnical failure. This paper reviews the conventional geotechnical monitoring sensors and the emerging Fibre Optic Sensing (FOS) techniques, pointing out their unique features and major differences. Recent advances in various FOS based monitoring systems, including Brillouin time domain distributed optical sensors and fibre Bragg grating (FBG) sensors, are investigated through a critical review of the laboratory studies and field applications used for underground geotechnical monitoring. Particular emphasis is given to fibre packaging, temperature compensation, installation methods and instrumentation performance in the underground environment. A detailed discussion of the advantages and limitations of each FOS monitoring system is also presented in this paper. Keywords: Underground geotechnical monitoring, Conventional geotechnical instruments, Distributed optical fibre sensors, Fibre Bragg grating, Brillouin optical analysis

The Dadushan Tunnel, which is located in the southwestern karst region of China in Guizhou Province, is one of the key elements of the Hukun High-Speed Railway. Cavities occur unpredictably in the tunnel, and well-developed karst conduits are frequently encountered. These features result in safety problems, such as water gushing and rapid flooding. In this paper, on the theoretical basis of the surface Magnetic Resonance Sounding (MRS) method, we propose Tunnel Magnetic Resonance Sounding (TMRS) in the tunnel space model and derive the expression of the MRS response signal with a vertical antenna. A direction angle formula is then created to calculate the perpendicular component of the transmitting field at arbitrary geomagnetic field and antenna directions. In addition, we present a comprehensive study on the TMRS based on forward modeling and numerical experiments. The relationship between the magnetic resonance signal response and the position and water content of water-bearing structures is obtained by forward modeling. In the numerical examples, the inversion results agree with the numerical model. The application of the method to a case study involving the Dadushan Tunnel indicates that the prediction results agree well with the excavation results. This paper establishes a theoretical basis for the development of a magnetic resonance sounding instrument for use in tunnels for the advanced detection of water-rich geological structures that can produce tunnel disasters.

Cḯxwicən (pronounced ch-WHEET-son) is a 2700 year-old ancestral village of the Lower Elwha Klallam Tribe (LEKT), located on the northwest coast of Washington State, U.S.A. The Cḯxwicən project has scientific values that broadly contribute to research in human ecodynamics and maritime foragers, given the scale of the project, excavation methods, and enormous quantities of faunal materials recovered. The village holds great significance to the LEKT as their traditional village, which includes a sacred burial ground. The project began under challenging circumstances, when the village was inadvertently encountered during a construction project, incurring huge political, social and financial costs. Commitment by the LEKT and Cḯxwicən scholars and other partners turned an “opportunity lost” into an “opportunity found.” This paper provides background to this remarkable site and project goals that guided the Cḯxwicən research project. The Special Issue papers showcase project results, including reflections by tribal members. Overall, the project shows the potential for archaeology and heritage to support reconciliation between tribes and archaeologists and broader society.

Dust generation resulting from various mining activities, such as excavation, loading, and transportation, is a major health and safety issue in underground longwall mines. This issue has been intensified by the increased production rates associated with modern equipment, technologies, and mining methods. In response to a report by the National Institute for Occupational Safety and Health (NIOSH), showing an increasing trend in Coal Workers’ Pneumoconiosis (CWP), the Mine Safety and Health Administration (MSHA) established new dust regulations mandating lower dust concentrations and more frequent dust sampling. This research focuses on the viability of enhancing dust control techniques by integrating a flooded-bed dust scrubber into a longwall shearer. To accomplish this objective, a full-scale physical model of a Joy 7LS longwall shearer, modified to accommodate the scrubber, was designed and fabricated at the University of Kentucky. Subsequently, this mock-up was transported to the longwall test gallery at the NIOSH Pittsburgh Research Laboratory (PRL) for testing. The paper provides a brief description of longwall mining, the operation of a flooded-bed scrubber, and a comprehensive overview of previous attempts at applying scrubbers to longwall shearers. Next, it describes the conceptual design and working principles of the flooded-bed dust scrubber as integrated into the shearer mock-up. The paper concludes with results of shakedown tests, indicating dust reduction from 46% to 53% in the return airways of the test gallery. These promising results demonstrate the potential health and safety benefits of the proposed concept and justify further investigation into its testing, refinement, and application.

This paper introduces the applicability of underwater photogrammetric survey within challenging conditions as the main tool to enhance and enrich the process of documenting archaeological excavation through the creation of 4D models. Photogrammetry was being attempted on underwater archaeological sites at least as early as the 1970s’ and today the production of traditional 3D models is becoming a common practice within the discipline. Photogrammetry underwater is more often implemented to record exposed underwater archaeological remains and less so as a dynamic interpretative tool. Therefore, it tends to be applied in bright environments and when underwater visibility is > 1m, reducing its implementation on most submerged archaeological sites in more turbid conditions. Recent years have seen significant development of better digital photographic sensors and the improvement of optical technology, ideal for darker environments. Such developments, in tandem with powerful processing computing systems, have allowed underwater photogrammetry to be used by this research as a standard recording and interpretative tool. Using multi-source photogrammetry (5, GoPro5 Hero Black cameras) this paper presents the accumulation of daily (4D) underwater surveys carried out in the Early Bronze Age (3,300 BC) to Late Ottoman (17th Century AD) archaeological site of Ropotamo in the Bulgarian Black Sea under challenging conditions (< 0.5m visibility). It proves that underwater photogrammetry can and should be used as one of the main recording methods even in low light and poor underwater conditions as a way to better understand the complexity of the underwater archaeological record., {"references":["G. F. Bass, \"Archaeology Under Water,\" in Ancient peoples and places,\nNew York, 1966.","J. Green, \"Maritime archaeology: a technical handbook,\" 1990.","M. 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Excavation nearby an existing tunnel is frequently encountered in underground construction, especially in congested urban areas. Essentially, the responses of the ground and existing tunnel to the nearby excavation is a complex soil-structure interaction problem. In this paper, extensive earlier contributions to this problem are organized according to their subject matters, including field observation, physical modeling, numerical simulation, and analytical method. This paper presents a review of selected representative researches that indicate the growing scenarios and an increase in our understanding of this problem. A summary of the limitations of each contribution is presented, as well as the expected aspects that need to be optimized in the future research. It is found that our knowledge is far from complete, and there are still gaps to be narrowed, particularly concerning the reliable measurement of soil stiffness, realistic modeling of excavation and tunneling construction, elegant soil constitutive models for natural soils, precise mechanical model and current status of the tunnel lining, etc. The review can help researchers and engineers to have a general knowledge of the relevant problem and provide guidance for more in-depth research.

Many factors that influence rockburst damage have been identified but the mechanism that drives rockburst is not fully understood. Weak planes such as faults and shears have been observed near excavation boundaries in many rockbursts and these structures must have played a role in these rockburst events. In this paper, the role of weak planes around tunnels in rockburst occurrence and damage was studied. A heterogeneous Abaqus2D explicit code was used to simulate dynamic rock failure in deep tunnels. Firstly, rock failure near the excavation boundary of a tunnel without any adjacent weak plane was modeled. Then a fault with different lengths, inclinations, and distances to the tunnel was added to the model and its effect on rock failure was simulated. The velocity and the released kinetic energy of failed rocks, the failure zone around the tunnel, and the deformed mesh were studied to identify stable and unstable rock failures. The simulation results showed that the presence of a fault near a tunnel could induce rockburst if the fault is positioned and oriented in such a way that it promotes high stress and low mine system stiffness. Finally, a rockburst occurred in the Jinping II drainage tunnel with an observed nearby fault was simulated. The modeling results captured the field observation of rockburst damage and confirmed that the presence of weak planes in the vicinity of deep tunnels is a necessary condition for the occurrence of rockburst. The presented methodology in this paper can be useful for rockburst anticipation and control during mining and tunneling in highly stressed grounds.

This paper explores possible synergies between techniques used to minimise seismicity in deep South African gold mines and their applicability to control coal bumps. The paper gives a summary of the techniques used in the deep gold mines and a critical appraisal if these are useful in coal mines. The techniques typically include control of mining rate, preconditioning, optimisation of extraction sequences and centralised blasting. Of particular interest to the coal bump problem is an experimental limit equilibrium fracture zone model implemented in a displacement discontinuity code. This was recently developed for the gold mines to enable the interactive analysis of complex tabular mine layout extraction sequences. The model specifically accommodates energy dissipation computations in the developing fracture zone near the edges of these excavations. This allows the released energy to be used as a surrogate measure of ongoing seismic activity and addresses a number of the weaknesses in the traditional usage of this quantity as a criterion for the design of seismically active layouts. This paper investigates the application of the model to a hypothetical coal longwall layout and the specific problem of coal bumps. Keywords: Coal bumps, Limit equilibrium model, Mining rate, Seismicity

The aim of the paper is to show how Eurocode 7: Geotechnical Design Part 1: General Rules (EC7) could be developed in order to be in accordance with practise in rock engineering and construction. A main feature is the geological uncertianties, which imply that a risk based approch should be used. The use of Geotechnical Category (GC) has therefore to be improved by (1) combining the consequences of a failure to the geological uncertainties before excavation, and (2) combining the consequences to the ground quality found after excavation. Three GC classes are needed to properly use the GC in rock construction. The paper further describes how GC influences the design, which design method to be applied. It also outlines the types of control, inspection and supervision to be applied in the various GC classes during various stages of a project. An example is presented showing how GC can be determined at various stages of a rock construction.

Adjacent development causes metro tunnel problems in soft-soil areas. A mathematical framework based on conventional integration and probabilistic method is purposed to include development-induced external loads into a metro tunnel design. In this framework, the development-induced load on the tunnel is a convolution of development intensity on the load-transfer functions over the adjacent area of the metro line. The development intensity is related to the urban development pattern, which is gathered by using categorized statistics. The load transfer functions adopt analytical solutions and empirical equations describing construction impacts on surrounding soil or structures. Monte Carlo simulations are used to generate the development impact, i.e., the load and displacement, on the basis of which the design value under a certain reliability index can be obtained. Therefore, determination of the development-induced load is divided into two stages. Part A of the paper introduces a statistical description of the development intensity of a location. Street blocks and metro stations are qualitatively cataloged with respect to development trends, periods, and frequencies. Maps, satellite photos, and street views are used to collect data in three Chinese cities: Shanghai, Guangzhou, and Nanjing. For each city, samples include the central station in the new district, and the central station, grouping station, and intermediate station in the built-up areas. In addition, residential districts inside and outside the inner ring in Shanghai are analyzed. The distribution of the building heights and stories with distance, the proportion of urban renewal with time, and the areas/depths/shapes of the excavations are obtained. The development patterns of blocks surrounding the metro line and the residential areas are analyzed. These data become input descriptions of development intensities in Monte Carlo simulations. Part B of the paper introduces the load transfer functions and the generation of loads on the tunnel.

During the process of archaeological excavation in the regions of Southeast China, collapse of test square usually occurs due to poor site-specific conditions. In this paper, the fast Lagrangian analysis of continua in three dimensions (FLAC3D) is employed to reveal the behaviors of test square. Taking the archaeological works in Liangzhu prehistoric earthen sites as the research background, the paper first introduces the geological setting, excavation procedure and monitoring scheme of the studied test square. Then, the deformation of four sides of the test square is modeled using FLAC3D. By comparison, it shows that the numerical results are consistent with the results from field monitoring. The result suggests that the numerical simulation can be effectively applied to representing the actual behaviors of the test square, which is helpful for determination of excavation scheme and stability evaluation of the test square during archaeological excavation. Keywords: Prehistoric earthen site, Archaeological excavation, Test square behaviors, Field monitoring, Numerical simulations

The present paper evaluates the effect of penetration depth of a diaphragm wall on the behavior of excavations in sandy soils using the finite difference method. A three-dimensional (3D) modeling is performed for excavation depths of 10 to 20 m. The analysis reveals the safe values of penetration depth for designing a diaphragm wall. Furthermore, the evaluations undertaken in the present paper indicate that the two-dimensional (2D) modeling to depths of 10 m is associated with large errors. In addition, the evaluation of the validity of the traditional method for the design of a steel strut has been discussed.

The present paper comprises research results regarding the usage of bone and antler artefacts by the inhabitants of Medieval Moldavia, taking as a case study an assemblage discovered in the medieval site of Old Orhei (Republic of Moldova). Numerous artefacts in different stages of manufacturing were identified, as well as artefacts with different wear levels. Our study emphasizes an important diversity in the typology of artefacts and in the anatomical and taxonomical selection of raw materials. The current paper seeks to continue the analysis of these types of objects that began a decade ago, when a part of bone and antler artefacts recovered from the archaeological excavations conducted in Old Orhei during the years 1947–2001 was investigated. The rich collection of bone and antler objects gained in the last six decades, illustrating the different segments of daily life, represents a valuable testimony of the urban material civilization during this historical period.

This paper presents new data on the initial settlement of the southeastern region of South America, based on recent research conducted at the Tigre archaeological site (K87), located in the middle Uruguay River basin, near the Uruguayan border with Brazil and Argentina. The current archaeological excavations carried out in this open-air site confirmed that it is a multicomponent site. A new series of 20 radiocarbon dates refined the chronology of recurrent human occupations at this site during the late Pleistocene (13,260 cal BP), the Pleistocene-Holocene transition (12,920–11,750 cal BP), the early Holocene (11,300–9300 cal BP), and the late Holocene (1180 cal BP), demonstrating the strategic importance of this site during the prehistory of the region. In this paper, we describe the archaeological and stratigraphic contexts of the site, and analyze the artifact assemblage of the early components. Tigre points recovered from the archaeological excavations confirm that this is a Paleoamerican point design that circulated in the region between 12,000–11,100 cal BP. In addition, associated with these points, bifaces, fractured preforms and a type of asymmetric biface with a crescent/half moon shape were recovered. These “crescent artifacts” show a high standardization in form, size and knapping technique, which is described in this paper. Finally, we discuss the geographic distribution of the Tigre points, the blade technology present in the Uruguay River basin, the presence of prestige artifacts during the settlement, and the chronology of the “Umbu tradition” of southern Brazil in relation to the previous and recent data obtained in the Tigre site.

For the safety and serviceability of an existing underground structure due to a new excavation below, a soil-structure separation model based on subgrade reaction analysis is proposed to study the responses of the existing underground structure. Our proposed method can determine the soil gap formation and then predict the soil gap dimension. Our method's length and height of the soil gap agree well with the data from two centrifuge tests. Parametric analyses are conducted in this paper to investigate the effects of the main influence factors on soil gap formation. A modified stiffness ratio, named soil gap coefficient Cg, is provided to determine the soil gap formation as a tool for preliminary assessment. The soil gap coefficient Cg is suitable for different soil types (different Young's moduli). This paper indicates that the soil gap is potentially formed beneath the existing underground structure when the soil gap coefficient Cg is less than 300.

The presence of geological structures such as faults, joints, and dykes has been observed near excavation boundaries in many rockburst case histories. In this paper, the role of discontinuities around tunnels in rockburst occurrence was studied. For this purpose, the Abaqus explicit code was used to simulate dynamic rock failure in deep tunnels. Material heterogeneity was considered using Python scripting in Abaqus. Rockbursts near fault regions in deep tunnels under static and dynamic loads were studied. Several tunnel models with and without faults were built and static and dynamic loads were used to simulate rock failure. The velocity and the released kinetic energy of failed rocks, the failure zone around the tunnel, and the deformed mesh were studied to identify stable and unstable rock failures. Compared with models without discontinuities, the results showed that the velocity and the released kinetic energy of failed rocks were higher, the failure zone around the tunnel was larger, and the mesh was more deformed in the models with discontinuities, indicating that rock failure in the models with discontinuities was more violent. The modeling results confirm that the presence of geological structures in the vicinity of deep excavations could be one of the major influence factors for the occurrence of rockburst. It can explain localized rockburst occurrence in civil tunnels and mining drifts. The presented methodology in this paper for rockburst analysis can be useful for rockburst anticipation and control during mining and tunneling in highly stressed ground.

The paper discusses two types of hydraulic structures: a) Hydraulic canals and penstocks. They are sensitive structures which typically do not tolerate ground displacements. Two cases are described: the Izbor canal and the Pampaneira penstock. A free water surface tunnel in the Izbor canal, was badly deformed by a landslide induced by a distant road excavation performed at a lower elevation. The Pampaneira penstock has survival 60 years of slow creep of a large ancient landslide. In both cases the proposed action to maintain both structures in operation involved a joint consideration of the landslide motions and an analysis of structural modifications and landslide-structure interaction. In both cases, the climate variability was present in the adopted solutions. b) Dams and the associated reservoirs. Dams generate a profound modification of river valleys because of the unloading effect of excavations and the modification of hydrogeologic conditions of extensive areas affected by the reservoir. The dam projects analyzed (La Brena II, Rules, Arenos and Yesa) provide an overview of case-specific situations which required also specific solutions. They are discussed in the paper. There is, however, a common scenario: the attitude to deal with creeping landslide motions. This point is controversial in practice and, in addition, it poses some fundamental issues in landslide understanding. Critical questions are the acceptable creeping velocity and the expected evolution of a creeping landslide. The cases described illustrate the variety of answers given in practice.

This paper presents a case study of super-large cross-section tunnel in Zhuhai, China. The excavation section of Gongbei tunnel is 336.8 m2. The construction method of freezing pipe roof and five-bench fourteen-step excavation is expected to be adopted, which is the first case in the world. The tunnel construction risk is great because the stratum which the tunnel passes through is mainly silt and the construction procedure is complex. In addition, the load-transfer mechanisms in tunnelling construction are not clear. In this paper, the field test method and numerical simulation were utilized to study the development and distribution of ground deformation and support deformation during the construction of Gongbei tunnel, and the mechanical responses of tunnel support structure in the tunnelling construction were investigated. The results showed that the ground deformation was uplifted with the excavation of the tunnel due to the freezing and grouting of the surrounding rock. The vault deformation during the excavation process was fluctuating due to Gongbei tunnel was excavated in several steps, which was generally in the state of settlement first and then heave. The peripheral convergence around the tunnel increased first and then tended to be stable with the excavation progress. The removal of temporary support had a slight impact on the convergence around the step C. Due to the existence of the pipe roof and freezing soil, the tunnel supporting stress was small, which ensure the safety of the tunnel structure. Stress results of steel frame of initial support showed that the vault and invert bent to the inside of the tunnel, and the side wall bent to the outside of the tunnel. The bending moment of the secondary lining was larger than that of the initial support due to the ring forming of the secondary lining separately, and the secondary lining might be damaged locally. After the temporary support was removed, the overall stress of the initial support and secondary lining increased slightly. The stress concentration of the secondary lining was relieved after thawing. The interface stress between secondary lining and tertiary lining was large. This case study might severe as a practical reference for similar tunnelling constructions.

This paper discusses common methodologies used in the prediction of cutter change time (the average time required for changing a cutter on the cutter head) and cutter consumption (the average number of cutters worn out for the excavation of 1000 cubic meter of rock) and highlights some potential pitfalls in the process. For this purpose, the prediction capabilities of these methods are discussed and their validity is examined using detailed data from many tunnels from around the world. The results of the statistical analyses and comparative studies show that in most cases, the NTNU model underestimates cutter change time. The average cutter change time is approximately 66 min for different cutter sizes and there is a minimal difference between corresponding values of the large versus small cutters. A new cutter change time model is also developed using a statistical analysis of a database of 50 TBM projects’ records based on the TBM penetration rate and quartz content of the rock. Analysis of the cutter consumption information of several tunnel projects has revealed that the available models for the estimation of this parameter require some revisions in the structure of their formulas. A new cutter consumption model is also developed based on a statistical analysis of a database of 135 TBM projects’ records. The results show the proposed new model’s estimates are in good agreement with the actual values with a high coefficient of determination (78%). The outcomes of this paper can improve rock TBMs’ performance and project planning evaluation especially for the early stage of a tunneling project.

There has been an increasing demand for underground construction due to urbanization and limited land in metropolitan cities in the recent years. However, the behavior of underground structures in soils and rocks is often not completely understood. The emergence of Artificial Intelligence (AI) techniques is envisaged to have a huge potential in addressing geotechnical problems that involve complex soil-structure interaction. This paper thus aims at reviewing the applications of AI techniques in studying underground soil-structure interaction, which focuses on aspects such as characterization of soils and rocks, pile foundations, deep excavations and tunneling. An overview of different AI techniques is provided and a list of key AI applications in underground works that have been published in the last ten years is also compiled to study the recent trend of machine learning techniques in underground construction. The capabilities and limitations of these techniques are discussed throughout the paper, to help readers understand various techniques that are suitable for different underground geotechnical applications. Lastly, some of the challenges that may be faced when applying the techniques are identified, and recent development of AI in geotechnical engineering is discussed in which possible countermeasures to overcome these limitations are highlighted.

Much of the research studies carried out in the past on tunnel fires are related to completed tunnels, i.e. when the tunnels are in operation. Although worldwide mechanized tunnel excavations are increasing every year, not much work is seen on the fire safety issues related to the construction of such tunnels. At the other end, the introduction of plows and shearers in mining with cutting power of more than 1000 kW and associated equipment like panzers and belt conveyors started in the mid-1960s. As a consequence, the need to evaluate the effect of this new technology on fire hazards in explosive gas medium emerged, leading to detailed research works which also helped to manage tunnel fire risks during tunnel boring machine (TBM) drives. In the light of experiences gained on methane/dust explosions, conveying belt fires in Turkish Coal Mines, and fires generated thereafter, guiding principles of managing the risk of tunnel fires during TBM excavations are developed and are discussed in this paper. Special attention is attired to two EPB TBMs excavating in the new Istanbul Airport Metro project under risk of methane explosion. Another source of tunnel fires in urban areas is the soil contamination by unexpected leakage of petroleum products which need special risk management programs during tunnel excavation using mine safety regulations. Determination of the safety risks and precautions taken in two cases on such grounds are also discussed in detail in this paper.

The paper presents evaluation of the newly proposed hypoplastic model for soft clays by modelling of the well-documented geotechnical failure of a deep excavation of Nicoll Highway, Singapore, in 2004. The marine clays present at the site are typical normally consolidated soft clays, exhibiting large deformability and stiffness and strength anisotropy. These features - anisotropy of asymptotic state boundary surface and the effect of normal consolidation on stress paths and stiffness anisotropy - have been included into the newly proposed hypoplastic model. In the paper, it is first demonstrated that the model predictions compare well with experimental data from element tests on Singapore clay and improve predictions over original hypoplastic model. Secondly, numerical simulations of Nicoll highway excavation focusing on specific cross-section within the collapse area are presented, showing good fit between inclinometer data and simulations up to the final stages immediately preceding the excavation collapse. The simulation results are compared for previous version of the hypoplastic model, along with Mohr-Coulomb model with effective and total stress parameters. Subsequently, the influence of the model parameters on simulation results is studied and it is shown that the parameters affecting extension strength are more significant than parameters affecting pre-failure non-linearity.

Environmental research of ancient landscapes in the coastal plains, river valleys and uplands of the Mediterranean shows how erosion and sedimentation studies play a significant role in the evaluation of the archaeological record at the regional and local scales. As a rule, directors of landscape archaeological projects nowadays involve physical geographers in order to study erosion and sedimentation as potentially influential post-depositional processes that may expose or cover up archaeological remains (long) after regions or sites were abandoned. This is a phenomenon in the literature known as geomorphological bias, i.e. bias caused by landscape taphonomic processes. Key question here is to what extent archaeological settlement patterns are an artefact of landscape change, with deposition obscuring large parts of the ancient Mediterranean landscape. At the same time, it is important for our knowledge of past societies to establish whether these landscape processes affected the sustainability of the human environments of sites and regions already while they were settled, and how people adapted to environmental changes in accordance with the socio-political and socio-economic context. Sustainability is defined in this paper as the capacity of a rural economy to endure in a given environmental and socio-economic setting. A key question from this perspective is whether erosion and sedimentation studies can help explain why some rural landscapes in the long run were economically more viable than others. Drawing on case studies from landscape archaeological and excavation projects of the Groningen Institute of Archaeology, this paper approaches Mediterranean sedimentation history in South and Central Italy from the angles of geomorphological bias and sustainability studies. The focus is on the coastal plains of the Sibaritide in South Italy and the Pontine plain in Central Italy, both of which have been subject to profound landscape changes caused by sedimentation starting at least in the Bronze Age, and caused by erosion in their hinterlands as the result of long term human impact in combination with climatic changes, sea-level change and neotectonics. Although already settled in pre- and protohistory, both coastal plains were targeted for the first time during phases of Greek and Roman colonization as areas of organized agricultural expansion (see Table 1 for a chronological overview of archaeological periods). However, in both cases long term sustainable exploitation proved difficult due to a complex of environmental, technological, socio-economic, and political factors.

Construction of an underground complex in congested urban areas calls for excavation of a group of foundation pits, referred to as a pit complex, which are usually surrounded by existing facilities. In such circumstances, the safety of the pit complex and facilities during the construction are of great concern. This paper presents a case of an underground complex construction in Shanghai soft clay. A pit complex composed of two deep excavations was excavated for a Comprehensive Transport Hub (CTH) and a commercial retail area and pedestrian concourse known as South Square (SS), which were connected to an operating metro station and a railway station. During the excavation, potential deformation of metro tracks and railway tracks were expected due to extensive soil unloading. To safeguard the railway and the subway, a zoned and staged construction technology was proposed, in which several temporary partition walls were constructed in addition to necessary supporting structures, to allow the large-scale deep excavations to be divided into several independent small-scale excavations. This paper discusses the rational construction sequence of these excavations as well as reinforcement measures in detail. The construction technology was examined by extensive field data. It is found that the maximum horizontal displacement of diaphragm walls ranged between 0.05% H e and 0.4% H e , where H e is the excavation depth. The vertical displacements of the railway tracks were well controlled, whereas the metro tracks heaved significantly due to unloading effect.

In the last decades mechanized tunnelling with Tunnel Boring Machines (TBMs) has spread, due to the sensible technological developments, allowing for higher advancement rates, huge excavation diameters (up to 17 m) and lower excavation costs. Methane inflows from gassy rock masses may represent a serious hazard in underground excavations and could cause expensive delays and, at worst, tragic accidents to workers. Consequently, if methane-air mixtures may be present, a safety engineering system should be designed and set up before starting the excavation works in order to prevent fires or explosions. Due to the impossibility to prevent the contemporary presence of explosive gas-air mixtures and ignition sources, TBMs have never been adopted for tunnelling in gassy rock masses until 2011 (excluding the tunnels excavated with TBM, where methane gas hazard was underestimated, consequently producing delays and unpredicted expenses). The paper describes the safety engineering system developed for the excavation of the Sparvo twin tunnels (Italy) with EPB–TBM. The machine (Herrenknecht S-574) was specifically designed to prevent the risk of having explosive gas-air mixtures and ignition sources in the same place and at the same time, hydraulically confining the volumes inside the machine. After a brief description of the case study, the paper illustrates the design criteria, the technological solutions adopted for the construction of the Herrenknecht S-574 and the operating procedures. Then, the paper focuses on examining and interpreting the methane monitoring results during Sparvo tunnel construction, that highlight the presence of huge volumes of methane. The developed safety engineering system allowed tunnelling without interruptions even with sensible gas flows. Current limits and possible improvements to the safety system described are also discussed.

Rockbursts frequently occur in deep underground excavations in a sudden or violent ejection of blocks of rocks from excavation walls. In addition to understanding rockburst mechanisms, rockburst control is an important issue for the safety of mining operations. Bolts and anchors are efficient measures to control rockbursts and permit the efficient exploration of underground excavations in mines. As mining depths increase, anchor and bolts with larger extension and higher loading capacity are needed. This paper introduces a Constant Resistant Large Deformation (CRLD) bolt which has been developed at the State Key Laboratory for Geomechanics and Deep Underground Engineering (GDUE), in Beijing, China. Static and dynamic tests were developed for this type of bolt. Advancements in Hopkinson tests were recently developed for CRLD bolts and Split-Hopkinson Tension Bar (SHTB) experiments for these bolts were performed. This paper presents the SHTB equipment and the results obtained with one and two CRLD bolts, as well a deep analysis of the obtained results. To better understand the complex nature of the problem, numerical simulations using several softwares were done for the case of one bolt, which had the dual goal of verifying the experimental and numerical results. In addition, the numerical predictions permit one conducting analysis the behavior of the bolt while targeting the development of large deformations. Finally some relevant conclusions are drawn.

This paper considers the performance of archaeology in the field. To do so it examines the notebooks recording the British Museum excavations in Cyprus during the period 1893–1896. Archaeologists have described the practices of writing and drawing as a performance that accords archaeology its disciplinary identity. However, there have not been systematic studies of the centrality of fieldwork in the disciplinary culture of nineteenth-century archaeology as there have been for other field sciences. Histories and geographies of science have shown that field knowledge was produced through a variety of spatial practices – including inscriptive practices – whose meaning, processes and intentions were embodied in the material artefacts of science, such as instruments and notebooks. Drawing on that work, this paper locates the British Museum notebooks as material objects of science in the disciplinary landscape of late nineteenth-century Cypriot archaeology and in British classical archaeology more broadly. In doing so, this paper furthers our understanding of how classical archaeology became established as a field-based scientific discipline in the later nineteenth century. This paper argues that the British Museum notebooks functioned as paper tools in the field: they constructed a new interpretative model of the ancient Cypriot artefacts that placed the island within the prehistoric Greek world. This archaeological model was established through the more accurate, schematic, abstracted and numerical syntax of the notebooks. Importantly, the British Museum archaeologists through the use of the notebooks as paper tools created a new entity, the excavated Cypriot artefact, that was firmly associated with the conditions of its discovery and evaluation processes.

The Lower Pleistocene unit TD6 at the Gran Dolina site (Sierra de Atapuerca, Burgos, Spain) has yielded human remains attributed to Homo antecessor. Many of these require some conservation treatment after recovery in order to be visible and consistent enough to be studied, safely handled, and preserved. In this paper we report the conservation tasks carried out on the human fossils collected during the second period of the excavation of unit TD6 (2003–2011). The main problems with these fossils are derived from the karst sediment filling in which they are found, essentially made up of clays, silt, and gravels that may be compacted and cemented and occasionally solidly adhered to the bones. In short, the treatments consisted of removing the matrix with manual and automatic tools, consolidating and rebuilding the fossils. The extent of treatments was adapted to the needs of the research and the entire process as well as the fossils before and after the intervention were strictly recorded. With this paper, we primarily aim to provide information that often remains unpublished and to share procedures that may be applied to fossils with similar problems. But in describing these treatments, we also aim to show that remedial conservation methodology is based equally on the mastery of the techniques and materials used for treatment and on the knowledge of fossils and the requirements of the studies conducted on them.

Archaeological prospection of earthen buried structures, namely non-fired sun-dried mud bricks mixed with organic material, is a critical challenge to address. In fact, this building material exhibits a very low geophysical contrast compared to its surroundings and, therefore, earthen structures are very complex to be identified using remote sensing. In order to cope with this issue, in this paper, we focus on the evaluation of satellite X-band radar data (COSMO-SkyMed) capability for detecting earthen buried structures in a desert area. The results obtained from satellite radar data have been validated for a test site in Pachacamac (Peru) by using unmanned aerial vehicle (UAV) and geomagnetic techniques. The test site is outside the fenced protected zone of Pachacamac, today in the tentative UNESCO list. This paper is the first attempt made until now in evaluating the detectability of earthen archaeological remains using satellite Synthetic Aperture Radar (SAR) data. Outcomes from our investigations clearly point out that the approach we adopted can be useful applied for preventive archaeology and for the planning of future excavation campaigns.

The paper presents geotechnical engineering studies for the design of a new lignite open-pit mine in central Poland. The lignite deposit occur in a deep tectonic rift formed in Mesozoic rock characterized by complex geological conditions. The rift is approximately 10 km long, 1 km wide and 50-250 m deep and filled with Neogene and Quaternary sediments. The design of the open-pit mine required geotechnical analysis to reveal possible problems that may occur during its construction and operation. The author of this paper had opportunity to perform slope stability studies and geotechnical analyses within the project conducted by Poltegor-Institute. The calculation procedure enabled determination of slope stability on the design of excavation and spoil dump. It included 21 analyses using Flac v.7 of which 14 regarded the slopes of the pit, 6 the slopes of the external spoil dump and one covered both areas. The results indicated that the factor of safety Fs ranges 0.75-1.65 for the pit and 1.12-1.60 for the dump. In risk areas slope inclination were lowered due to likelihood of developing of landslide processes. These included spoil dump area close to S-8 road. Due to relatively limited geotechnical data in same areas especially on northern slope and western part of spoil dump detailed geotechnical investigations will be necessary. The instability problems can be caused by the groundwater conditions and the presence of high compressibility organic peats in the spoil dump bedrock layers. Comprehensive identification and monitoring of geotechnical risks for the mine slopes and storage of overburden should be a continuous process. This activity should start from the beginning stages of construction and should be conducted also during exploration and continuing to mine final reclamation to reduce potential natural hazard impact on mining and the natural environment.

In this paper, the relationship between the dynamic surface subsidence and overburden separated strata has been studied under the condition of sedimentary coal measure strata. When the underground coal seam is mined, the ground surface subsidence will be caused. The surface subsidence is caused by the goaf clearance passing along the overlying strata up to the surface. During the course, the bed-separation space would be generated and its size directly affected the value of mining goaf passing up to the ground - the surface subsidence. It shows that the surface subsidence is closely related with overburden separated strata. Therefore, the research on the dynamic development law of overburden separated strata contributes to recognition and prediction of surface dynamic subsidence, which is the important basis for the control of mining subsidence damage. In this paper, the whole processes form cracking, propagation, to closure of the mining overburden separated strata are analyzed in the first chapter. The various steps of surface dynamic subsidence, from the initial step, the active step, and then to the recession are researched. And then the corresponding relationship between the surface dynamic subsidence and overburden separated strata is studied and its model is established for analyzing factors of geological and mining that influenced this relationship. At last, a similar material model for coal measure strata in sandy shale is established and carried on the excavation experiment of coal seam. Then by use of the test, the development law of mining overburden separated strata is studied, and the space-time corresponding rule of the surface subsidence and overburden separated strata is analyzed. And on this basis, we find the relationship between the surface subsidence and overburden separated strata. Based on allometric growth of mining overburden separated strata, which would provide a new research and analysis method for control and prevention of mining subsidence damage, we establish the model of mining subsidence.

Recent and ongoing technological developments make the application of unmanned aerial platforms increasingly accessible for archaeological research and heritage management. While the effectiveness of drones for documentation purposes of standing monuments and excavations has been amply demonstrated in recent years, there are also promising developments in their application for landscape archaeological projects. In this paper, the potential use of drones for the detection of subsurface archaeological remains in mountainous, Mediterranean landscapes is explored by presenting a case study in Molise, South Italy. In this rugged, Apennine area, traditional aerial archaeology approaches have in the past failed to yield good results as regards the detection and documentation of subsurface structures through crop marks. Recent experiments with low altitude, both vertical and oblique aerial photography using small, consumer friendly UAV's drones have, however, produced important and clearly readable information about the existence and extent of subsurface features in a series of sites in the Tappino Valley in Molise. This paper presents the first results of a case study of a complex rural site of the Classical-Roman period. Consequently, the paper discusses the potential value and feasibility of UAV's for archaeological research and cultural heritage management. In particular, the potential of the integration of UAV imagery in existing standard landscape archaeological research methods, such as field survey and geophysical prospection, is discussed. It is concluded that the targeted use of small remote controlled aerial platforms can significantly add to existing practices of both site-recognition and heritage management in the heavily threatened Mediterranean landscapes, and that it can be feasibly and efficiently integrated within standard methodologies applied in field survey projects.

In the past few decades, the number of tunnels constructed next to an existing tunnel has been gradually increasing in order to accommodate infrastructure needs in congested urban cities. When a new tunnel is constructed adjacent to an existing tunnel, both the relative position of the tunnels and the construction sequence affect the ground settlement and internal forces in the linings of both tunnels. Therefore, it is important to study the influence of these factors and their relationship to tunnel construction. A review of twin tunnelling induced ground settlement is presented in this paper. A wide range of data is collected, summarized, and compared with each other to infer interaction phenomenon related to ground settlement. This data is gathered from published field observations, laboratory tests, and finite element analyses. The paper begins with an overview of single tunnelling induced settlements, volume losses, and factors which can affect twin tunnelling induced ground settlements. Next, a summary of the effects of construction sequence, pillar width, and cover depth, among other influencing factors, has been presented for four twin tunnelling configurations including (i) side-by-side, (ii) piggyback, (iii) perpendicularly crossing, and (iv) offset arrangement twin tunnelling. The paper also presents a summary of available techniques to calculate ground settlements induced by a new tunnel excavation in the presence of an existing tunnel. Finally, the paper summarizes available knowledge on ground settlement induced by various twin tunneling arrangements and identifies known unknowns.

This paper introduces the numerical simulations of fracture transmissivity changes caused by the excavation damage zone, thermal loading and glaciation, which can occur during the lifetime of the geological repository. The fractured rock model with the deposition tunnel is constructed using three-dimensional discrete element methods with seventy-one fractures. The transmissivity changes induced by stress re-distribution after excavation are analyzed using stress-dependent fracture properties and compared to the field observation at the Aspo Hard Rock Laboratory. After the stress re-distribution, the thermal and glacial loadings are applied and an irreversible increase in fracture transmissivity is captured. The transmissivities of the fractures are dominated by both normal deformation and shear dilation induced by the thermal and glacial loads. After each simulation ends, the normal deformations dissipate reversibly, and the effect of the irreversible shear dilation only remains on the fracture transmissivity. The detailed mechanisms of the deformations and shear slip during each simulation are analyzed by tracing the stress path on the fractures. In addition, the fracture behaviors are categorized as reversible or irreversible changes. This paper suggests that the transmissivity should be treated as a dynamic variable that can be disturbed by the excavation damage zone, thermal loading, and glaciation during the lifetime of the geological repository.

Failure of rock mass in deep underground excavations could be attributed to a broad range of performance malfunction, from plastic yielding of rock, generation of macro cracks on the boundary of the excavation, gravity driven rockfalls or even complete stress-induced collapse. The failure criteria determine the stress level (or strain level) at which the rock mass loses its load-carrying (or strain-carrying) capacity. Determination of the state of underground stability can be successfully achieved through implementation of appropriate failure criteria within the numerical analyses’ tools. The choice of failure criteria in numerical stability analysis plays a key role in defining the behaviour of an underground excavation. A failure criterion will be useful only if selected based on the correct mechanism of failure. Plus, a right choice of failure criterion, significantly reduces the errors of quantifying an excavations behaviour. Therefore, this paper offers a critical review of the most common stress-based and strain-based failure criteria used in numerical stability analysis of underground excavations. Particular attention is paid to characterize different mechanisms of underground failure and recommendations are formulated for each failure mode. In addition, this paper addresses the theoretical considerations for the applicability of different failure criteria and highlights the practical limitations for their numerical implementation.

Cave-ins are very frequent in the construction industry and present a very serious risk for workers who operate inside trenches or excavations. Studies show that excavations or trenches in Quebec sensitive clay soils are extremely hazardous due to possible severe and sudden loss of soil shear strength. Many North American and European construction safety authorities have already adopted proper methods and excavation protection practices according to their soil classification. This paper reviews existing construction codes and guidelines, as well as published research studies related to worker safety and protection in excavations and trenches in sensitive clay soil. The paper also discusses the needs for research on prevention strategies to eliminate potential cave-in risk sources from occurring in Quebec sensitive clay soil.

This paper deals with the analysis of overbreak in tunnels excavated with the drill-and-blast method. The overbreak phenomenon has many negative impacts on tunnelling organisation and economy and its precise assessment plays a fundamental role in the process of construction optimisation. The study proposes an operative methodology to estimate overbreak volumes and to distinguish so-called technical overbreak, mainly related to drill-and-blast design and execution, from geological overbreak, typically influenced by rock-mass characteristics. The approach was developed and implemented during the excavation of the Brenner Base Tunnel (BBT) and was based on the interpretation of tunnel laser scanning surveys and high-resolution images of the excavated surfaces. The analysis of more than 1,800 m of excavation from three different tunnels of the BBT system allowed to identify the main factors influencing the technical and the geological overbreak. An empirical model for overbreak prediction, based on the Rock Mass Rating index and the length of blast holes, is subsequently presented and validated in the last part of the paper.

This paper examines the effect of different geological and mining factors on roof stability in underground coal mines by combining field observations, laboratory testing, and numerical modeling. An underground coal mine in western Pennsylvania is selected as a case study mine to investigate the underlying causes of roof falls in this mine. Three-dimensional distinct element analyses were performed to evaluate the effect of different parameters, such as the variation of immediate roof rock mass strength properties, variation of discontinuity mechanical properties, orientations and magnitudes of the horizontal in-situ stresses, and the size of pillars and excavations on stability of the immediate roof. The research conducted in this paper showed that the bedding planes play an important role on the geo-mechanical behavior of roofs in underground excavations. Therefore, an appropriate numerical modeling technique which incorporates the effect of discontinuities should be employed to simulate the realistic behavior of the discontinuous rock masses such as the layered materials in roof strata of the underground coal mines. The three-dimensional distinct element method used in this research showed the capability of this technique in capturing the important geo-mechanical behavior around underground excavations.

With rampant growth and improvements in drilling technology, drilling of blast holes should no longer be viewed as an arduous sub-process in any mining or excavation process. Instead, it must be viewed as an important opportunity to quickly and accurately measure the geo-mechanical features of the rock mass on-site, much in advance of the downstream operations. It is well established that even the slightest variation in lithology, ground conditions, blast designs vis-à-vis geologic features and explosives performance, results in drastic changes in fragmentation results. Keeping in mind the importance of state-of-the-art measurement-while-drilling (MWD) technique, the current paper focuses on integrating this technique with the blasting operation in order to enhance the blasting designs and results. The paper presents a preliminary understanding of various blasting models, blastability and other related concepts, to review the state-of-the-art advancements and researches done in this area. In light of this, the paper highlights the future needs and implications on drill monitoring systems for improved information to enhance the blasting results. Keywords: Rock blasting, Drill monitoring parameters, Rock factor, Drill rod vibrations

This paper presents the results of a large-scale fieldwork project of interdisciplinary studies on the Middle Paleolithic settlement in the western Tian Shan piedmont. A complex of newly discovered “loess Paleolithic” open-air sites near Yangiobod (Uzbekistan), Katta Sai, was excavated. The excavations allowed identification of a new variant of human adaptation in the regional Middle Paleolithic. In the light of the newest anthropological and genetic data, this new archaeological sites fit to the current studies on the relations between different human species during the Middle and Early Upper Paleolithic in Central Asia. Geoarchaeological investigation of the sites has shown that the Paleolithic assemblages of Katta Sai are not preserved in situ. Cultural levels suffered from rill erosion, and most of the artifacts were re-deposited by water flow, and accumulated in secondary positions on the bottom of the branched rill system. This paper aims to reconstruct the subsequent processes of the site formation and to present the complicated geological situation of the studied sites of the Katta Sai complex, with implication for the archaeological interpretation of Paleolithic assemblages of the region.

Prediction of ground condition ahead of tunnel face is the most important practice during the construction of tunnel. Prior to excavation, geological condition are studied in order to avoid any potential excessive water ingress or tunnel collapse that may cause fatality. In addition, the prediction aids to upsurge the production and safety of the construction. Techniques on the prediction of ground condition ahead of tunnel face have significantly advanced over the years, there; Tunnel Seismic Prediction (TSP) and probe drilling method. In this study, probe drilling method data is chosen to study the ground condition and rock strength. This paper aims to predict the strength of rock based on the probe drilling record by using statistical method. Parameter studied taken from this probe drilling data is drilling speed. Based on this parameter, k-means clustering is used to cluster the drilling speeds that are possible to occur in relation to the ground condition. The changes of drilling properties observed during the probe drilling provide some indication on the strength of the ground, the presence large of cavities, type of rock and the presence of groundwater. The information records will be interpreted in order to forecast the anticipated ground condition. This paper provides a brief overview of the rock strength cluster encountered along the NATM-4 tunnel at Hulu Langat, Selangor.

The paper reports some geotechnical aspects of the design and construction of the San Pasquale Station, intermediate along Line 6 and located close to the sea and at the same time within one of the most fascinating district of the city known as Chiaia borough. The station required an excavation deeper than 25 m, almost entirely located in pyroclastic sand below the groundwater table. The main shaft is 85.5 m long and 24.1 m large, containing also the whole length of the pedestrian platform while a single large section tunnel, built before the excavation of the station shaft, accommodates the two operating rail tracks. In the paper monitoring data will be presented and discussed. Settlements and horizontal displacements represent certainly very significant outcomes among the observed data. Their variations along with time and main construction steps are first of all presented in the paper. The monitoring data have also been submitted to a process of careful interpretation based on the use of numerical analyses to better understand the interaction of deep excavation with urban area. The FEM code Plaxis has been adopted for such a purpose adopting advanced constitutive soil models which are available in the code library.

When a large span loess tunnel is excavated, the rock mass is disturbed, and it is difficult to form a load-bearing arch under shallow depth region. As a result, the structural deformation is complicated. This paper analyzed the deformation of 18 sections in Grade V rock mass and the primary support structural force of 2 sections in a case study of a highway loess tunnel in the large span loess highway tunnel group of Huangyan Traffic Capacity Expansion Engineering in Northern Shaanxi Province-Jianzicha No.2 Tunnel. The analyzed results were combined with the FLAC 3D numerical simulation to study the deformation of rock mass in Jianzicha No.2 tunnel and the stress characteristics of primary support. The results showed that: (1) The time-space relationship curve of arch deformation indicated three stages of “rapid deformation stage -continuous deformation stage-slow deformation stage” in the construction by annular excavation with reserved core soil method. (2) The rock mass pressure distribution of tunnel basically presented the bilateral symmetry characteristics. The rock mass pressure distribution of arch was relatively uniform, and the rock mass pressure at the invert was relatively large. (3) The outer and inner sides of primary support arch steel rib was subjected to compression, and the stress distribution was relatively uniform and large. (4) The primary support shotcrete was mainly subjected to compression, and the stress distribution was basically characterized by bilateral symmetry. The stress distribution of shotcrete at the arch was relatively uniform and large, and the stress of shotcrete at the inverted part was relatively small. This paper studied the time-space law of supporting structure deformation in the shallow section of Ⅴ grade surrounding rock, and designs the supporting parameters of Ⅴ grade surrounding rock for large-span loess highway tunnel, which has guiding significance for the construction of similar projects in the future.