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Assessment of seismic resilience of critical infrastructure such as liquefied natural gas (LNG) storage tanks, is essential to ensure availability and security of services during and after occurrence of large earthquakes. In many projects, it is preferred to build energy storage facilities in coastal areas for the ease of sea transportation, where weak soils such as soft clay and loose sand with liquefaction potential may be present. In this study, three-dimensional finite element model is implemented to examine the seismic response of a 160,000 m3 full containment LNG tank supported by 289 reinforced concrete piles constructed on liquefiable soil overlaying the soft clay deposit. The seismic soil-structure interaction analysis was conducted through direct method in the time domain subjected to the 1999 Chi-Chi and the 1968 Hachinohe earthquakes, scaled to Safe Shutdown Earthquake hazard level for design of LNG tanks. The analyses considered different thicknesses of the liquified soil deposit varying from zero (no liquefaction) to 15 m measured from the ground surface. The key design parameters inspected for the LNG tank include the acceleration profile for both inner and outer tanks, the axial, hoop and shear forces as well as the von Mises stresses in the inner tank wall containing the LNG, in addition to the pile response in terms of lateral displacements, shear forces and bending moments. The results show that the seismic forces generated in the superstructure decreased with increasing the liquefied soil depth. In particular, the von Mises stresses in the inner steel tank exceeded the yield stress for non-liquefied soil deposit, and the elastic–plastic buckling was initiated in the upper section of the tank where plastic deformations were detected as a result of excessive von Mises stresses. However, when soil liquefaction occurred, although von Mises stresses in the inner tank shell remained below the yield limit, localised stress concentrations were observed in the lower section of the tank near the base, increasing the risk of the elephant foot buckling. The lateral displacements, shear forces and bending moments in the piles increased with increasing depth of the liquefied soil. Indeed, increasing the pile lateral displacement amplified the bending moment at the pile head, thus resulting in increases in the pile bending moments especially when the liquefied soil depth exceeded one third of the entire soil deposit. In particular, the bending moment at the pile head exceeded the yield moment capacity of the pile and subsequent plastic hinges were formed. Moreover, when the thickness of the liquefied soil was more than half of the entire soil depth, the mobilised bending moments in the piles exceed the ultimate moment capacity of the pile and thus total failure of the piles were observed. In addition, in the absence of liquefied soil layer, the inertial interaction had a dominant impact on the pile response in this study. However, with increasing the thickness of the liquefied layer, further loads were developed in the piles due to amplified kinematic interaction, while the inertial interaction-induced loads decreased. [ABSTRACT FROM AUTHOR]

Simplified procedures, capable of predicting the main effects of soil-structure interaction (SSI), involving minimum computational effort are desired in engineering practice. Besides, user-friendly approaches can be incorporated into guidelines or practical recommended procedures. Nevertheless, approximate solutions need to be carefully validated through rigorous analytical or numerical methods, as well as by the comparison with experimental results or field measurements. In the case of piles, the flexibility of the soil-foundation system plays a fundamental role in structural design and the evaluation of the pile group effects still represents a crucial task in practical problem. In this paper, a Boundary Element approach based on the Stiffness Matrix Method (Kausel in Fundamental solutions in elastodynamics. A compendium, Cambridge University Press, England, 2006) is employed to investigate the key features of SSI, by comparison with the actual field data collected by Stewart et al. (Empirical evaluation of inertial soil-structure interaction effects. Rep. No. PEER-98/07, Pacific Earthquake Engineering Research Center, 1998) from instrumented sites and structures. [ABSTRACT FROM AUTHOR]

This paper presents a three–dimensional linear numerical model for the dynamic and seismic analysis of pile-supported structures that allows to represent simultaneously the structures, pile foundations, soil profile and incident seismic waves and that, therefore, takes directly into account structure–pile–soil interaction. The use of advanced Green's functions to model the dynamic behaviour of layered soils, not only leads to a very compact representation of the problem and a simplification in the preparation of the data files (no meshes are needed for the soil), but also allows to take into account arbitrarily complex soil profiles and problems with large numbers of elements. The seismic excitation is implemented as incident planar body waves (P or S) propagating through the layered soil from an infinitely–distant source and impinging on the site with any generic angle of incidence. The response of the system is evaluated in the frequency domain, and seismic results in time domain are then obtained using the frequency–domain method through the use of the Fast Fourier Transform. An application example using a pile-supported structure is presented in order to illustrate the capabilities of the model. Piles and columns are modelled through Timoshenko beam elements, and slabs, pile caps and shear walls are modelled using shell finite elements, so that the real flexibility of all elements can be rigorously taken into account. This example is also used to explore the influence of soil profile and angle of incidence on different variables of interest in earthquake engineering. [ABSTRACT FROM AUTHOR]

Polymer pile products are currently being used in marine environments in pile-supported fender systems due to their superior resistance to this environment over traditional materials. The piles in fender systems are laterally loaded elements, which dissipate energy through flexure. Due to the anisotropic nature of the polymer materials, shear deformations can become significantly large. The goal of this analytical study was to use material properties found in the literature to determine the significance of flexural shear deformations. It was ultimately found that the shear effects in these materials are significant. The significance varies based on the stiffness of the soil. The greater the stiffness, the more influence the shear has on the total deformation. Due to the interdependent nature of the observed results, it is recommended that the shear effects must always be considered when designing with currently available polymer piles. [ABSTRACT FROM AUTHOR]

Background: Stapled Hemorroidectomy is more popular alternative, has higher safety profile, and quickly established than the open Hemorroidectomy procedure. Objective:The study aimed to compare between the early post-operative outcomes of open haemorrhoidectomy and stapled. Methods:A total of 50 patients between the age group 20 to 70years who were diagnosed with grade 3 and grade 4 hemorrhoids, were divided into two groups equally. Stapled haemorrhoidectomy contains 25 Patients undergoing and Open haemorrhoidectomy contains 25 Patients. Comparative analysis between the two groups were done based on student's T test using SPSS 24 software version. The level of significance was set to 5% (p < 0.05). Results: There were 52% males and 48% females in Stapled haemorrhoidectomy groups and 64% males and 36% females in open haemorrhoidectomy group. 48% patients had grade 3 and 52% had grade 4 haemorrhoids in Stapled haemorrhoidectomy groups, and 44% had grade 3 and 56% had grade 4 haemorrhoids in open haemorrhoidectomy groups. In 16% of patients in stapled haemorrhoidectomy group and 24% of patients in open haemorrhoidectomy group blood loss was seen. In 12% of patients with staple haemorrhoidectomy and in 20% of patients with open haemorrhoidectomy was necessary supportive stitching. 52% of patients in open haemorrhoidectomy was observed residential prolapse but not in stapled haemorrhoidectomy patients. In the stapled group the duration of hospital stay (in days) was 1.96±0.82 days as compared to 3.98±0.78 days in the open group. Comparing to only 4% in the open group, 80% patients were discharged within 2 days in stapled group. In the open group at the end of 4 days 72% were discharged. Conclusions: Open haemorrhoidectomy at Milligan-Morgan is not easy as stapled haemorrhoidectomyinvolves shorter operation, fewer postoperative pain and an analgesic need, shorter hospital stays and a faster rehabilitation, earlier work back, the study confirms. [ABSTRACT FROM AUTHOR]

Numerical investigations on the shielding efficiency of single piles and pile groups in the wave field of a stationary or moving harmonic load This article presents results from finite‐element analyses on the kinematic interaction of single piles and pile groups. The focus lies on the assessment of the resulting transfer functions due to an excitation with a stationary or moving harmonic vertical point load. A moving constant load is also considered. The soil is modelled as a linear viscoelastic continuum, and further distinguished between a half‐space and a stratum on rigid base. The finite‐element model has been optimised with respect to its size and the fineness of the discretization. The achieved accuracy is assessed on the basis of comparisons with exact solutions for the near‐ and the far‐field. A frequency range between 20 and 40 Hz is examined. The results on the vertical response show that the vibrations of the pile head are considerably smaller than those of the free‐field and that this reduction is more pronounced at higher frequencies. The connection of the piles through a rigid massless cap leads to an additional reduction of the vibration level in the pile group. In the case of a moving load, the shielding efficiency, as indicated by the emanating shadow zones, becomes stronger as the load passes by at minimum distance. [ABSTRACT FROM AUTHOR]

The paper presents a method of calculation of rotationally symmetric circular plates, supported on piles and having a stiffness changing in the radial direction. The method is based on the superposition rule, i.e., an initial plate supported on piles is treated as a combination of two plates clamped on a middle post with a small diameter, wherein the first plate is loaded such as the initial one and the second plate is loaded by forces occurring as reactions in the piles of the initial plate. Obtained results are concordant with the engineer's intuition and a comparison of results for various plates shows high similarity between each other. As works dealing with the analogical problems have not been found in the literature, then this concordance and similarity can be acknowledged as a premise showing a correctness of the presented method. The results obtained in the method have been compared to results obtained in a professional FEM-based environment for building construction design. It has been stated that in many cases the results of the presented method are highly concordant to those of the FEM, though in some cases discrepancies exist. However, the FEM is an approximate method, especially if related to plates, thus its results should be taken with a great care. In general, it can be stated that the presented method deserves an attention and further studies. [ABSTRACT FROM AUTHOR]

Aims. The purpose of this work is to justify the reliability of the developed models of pile foundations on the data of field observers and to demonstrate the feasibility of using pile foundations to increase the stability and bearing capacity of the NPP structures foundation using the example of reactor building (RB). Methods. The data of field observers for the settlement of the RB are presented. The expressions for calculation of the static stiffness of the contact surface of the slab bottom and soil medium, as well as for pile foundations taking into account the effects of interaction of grillage and pile field with the soil media with a general character of displacement of a circular cross section pile are submitted. A spatial three-dimensional finite element static model of RB was developed together with the soil base. Isolines of vertical movements of RB fundamental slabs for natural foundations, as well as for pile foundations for normal operation are shown. A comparative analysis of the data of field observers with the calculation results allows us to justify the reliability of the developed model of the pile foundation. Results. The calculations of the foundation yield correspond to all the period of operation including construction, and the results of observations relate only to the period of operation that explain the difference. A comparative analysis of the data of field observers with the calculation results allows us to justify of the strong effectiveness of realization of pile foundation for the massive structures on soft soil bases.

The main objective of this work is to present an innovative method of numerical modeling of anchored piles system acting as a road protection against landslide, called the “2D/3D method”. Firstly, short description of the problem and “state of the art” review are included. An effective methodology of the design supported by the numerical analysis, solving the problem of interaction of a periodic system of piles and the unstable soil mass is presented, for which some detailed information about proposed numerical approach is given. The key idea of 2D/3D method is to join the pile with the 2D plane strain continuum by fictitious connectors of Winkler type with P-Y properties identified during the analysis of a subsidiary 3D problem. Practical example of usage of proposed approach to a real case of a road endangered by a landslide then protected by the piles system is presented. On the base of this example, a discussion about important design issues like internal forces in piles (mainly bending moments) and anchors (tensile forces) or overall stability of the soil-structure system is done.

The roughness elements are efficient tools to control the features of the hydraulic jump in the rectangular stilling basins. The present study suggests the use of modified elements to control the features of the free jump. The proposed tool is an incomplete circular pile. The use of piles in a one row with the different setup has been investigated. The measurements showed that the case of piles with the comparative summation areas A/∆=6.72 and the comparative distances between piles X/H1 =0.0 reduced the comparative height and length of the free jump by 11% and 24.6%, respectively. The paper detected the necessary helpful statistical formulas for the phenomenon.

Vehicular collision is one of the leading causes of structural failure and the large impact loading leads to failure of the bridge structure. Therefore, the structural behavior of bridge substructure including the piles is the chief topic in this paper. Numerical finite element analysis (FEA) software ANSYS was used for simulating the FE model. This paper describes a numerical analysis of the pile structural behavior of a bridge substructure under vehicle collision as a case study. The aim of this case study was to evaluate the response of the bridge substructure and soil to impact loading as well as to discuss the interaction between soil and piles. Validation of the model was conducted by comparing the experimental result from pendulum impact test with the numerical result from FEA software. Detailed 3D FE models of the bridge superstructure, substructure, and soil were developed for this purpose. The bridge model was developed on the basis of the verified model’s material detail and contact types. A half-length bridge deck with two piers was supported at the bottom edge. Pile caps and piles were embedded into rectangular soil. Soil springs were also defined to emulate the behavior of soil. An impact force-time history was subjected to the bridge pier; the response of bridge substructure and soil are also discussed. The numerical FE bridge model is able to provide an explanation of the displacement of bridge substructure and soil. Responses of the bridge substructure and soil were primarily concentrated the lateral displacement, vertical displacement, and equivalent stress. This response was investigated in accordance with the length, height, and depth of the bridge structure component. In addition, the soil–pile interaction under vehicular collision was also inspected. On the basis of the obtained results, it can be deduced that the soil is affected by the movement of piles and the soil itself after being subjected to the impact load.

This paper studies the effect of loading eccentricity and pile spacing on the ultimate lateral soil resistance of twin-piles using finite element limit analysis and analytical upper bound plasticity methods. Two kinematic mechanisms corresponding to the failure modes produced by the advanced finite element simulations are postulated with different eccentricity and pile spacing cases. Comparisons have shown excellent agreements between the two approaches. A series of parametric studies are then subsequently performed. Numerical results have shown that loading eccentricity considerably affects ultimate lateral soil resistance, leading to a maximum reduction of 50%. In addition, the curve of normalised pile resistance versus pile spacing ratio is dissimilar to that without considering the effect of loading eccentricity. The proposed solutions and failure mechanisms in this study will provide a deepened insight on the performance of twin-pile group under eccentric loads.

Analysis of the applicability of wave model solution to evaluate the variation of the dynamic stiffness in the pile foundation versus the distance between piles at the vertical vibrations; both experimental data from references and our own measurements in field are involved. To justify the reliability of the solutions of the wave models used to determine the dynamic stiffness values of the pile foundations at the vertical vibrations, we use the data obtained experimentally for the determination of natural frequencies in the cap-bound groups. The data obtained for the natural frequencies of 3×3 floating piles with different distances between them are considered. In addition, the data found at the forced vertical vibrations of the cap-bound groups of 2×2 piles under different loads and at different distances between the piles are involved. Processing of available amplitude-frequency curves involves the solution of the inverse problem with the theory of nonlinear vibrations to determine the parameters of the “pile group – soil” system, namely the effective mass, stiffness, and damping. The correlation between the measured and predicted data is evaluated by using the data obtained at the description of the pile groups in soil behavior. It has been found that the relations obtained at the solution of wave models and used to calculate the dynamic stiffness at the vertical vibrations of pile foundations consider the mutual effect of the piles in the group and permit satisfactory accuracy of the results. The maximum discrepancy between the results and experimental data is 15 %.

Root piles are injected and installed during mortar shaft construction, using pressures of up to 500 kPa. The executive control is typically done through static load testing, an expensive and time-consuming method. Static load tests on eight controlled piles (diameters between 310 mm and 410 mm) were performed, aiming at evaluating pile ultimate load. This study suggests an innovative, non-destructive approach to validate root pile field performance, using a digital speedometer connected to the drilling rig’s rotating head. The proposed method monitors variables related to bearing capacity during pile installation and proposes an empirical equation to estimate the ultimate bearing capacity of root piles. For the assessed piles, the predictions obtained with the proposed equations agreed fairly well with results from static load tests, proving it as a feasible and helpful option for the executive control of root piles, especially when load tests are not available.

Forced vertical vibration tests were carried out in the field on 5.8 m long driven single steel pipe pile with external and internal diameter of 0.166 m and 0.154 m. Tests were conducted on single on 2 × 2 group piles under a static load (Ws) of 15 kN. The field test results include the determination of frequency-amplitude responses and soil-pile separation length for single pile and group piles, respectively. The frequency-amplitude responses from the experimental results were compared to the theoretical predictions based on the continuum approach analysis utilizing the soil-pile separation depth from the experimental investigation. It was noticed that the theory well anticipates the nonlinear characteristics of the frequency-amplitude responses of the soil-pile system. [ABSTRACT FROM AUTHOR]

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In this paper, two types of bridges were taken to carry out the analysis and design according to the AASHTO Code and the SAP2000 program, in the beginning, work is done using AASHTO Code and both bridges are designed and analyzed, the first one was the suspension bridge and the second was a bridge supported in the pier region only. The two models, 16 piles with a diameter of 3.8 m were carried out on each pier. After that, the two models are analyzed and designed according to the SAP2000 program to calculate moment, shear and deflection for both bridges. So that the two models are compared based on torque, shear, impact loads and deflection to find out which one of the two models is more suitable for use in a long girder span. The comparison between the AASHTO Code and the SAP2000 program is also made based on the loading to show its effect on the stability design. The AASHTO code and the SAP2000 program are the most appropriate when analyzing and designing for two models. There is a slight difference in moment where the proportions were approximately (6-9)%. As for shear for both methods, the values for the suspension bridge were greater than those of the supported bridge. The difference was about (27-26)%. [ABSTRACT FROM AUTHOR]

This paper presents a closed-form solution on the steady dynamic response of circular piles embedded in inhomogeneous soil. The soil is modeled as a viscoelastic continuum, and the pile is modeled as a one-dimensional elastic shaft. Fictitious soil pile model and Hamilton's energy principle are introduced to deduce the equations governing the layered pile–soil system. Impedance transfer method and iterative algorithm are deduced to decouple the pile–soil dynamic interaction. The results show that the modulus and thickness of inhomogeneous soil profile play a more significant role in the dynamic stiffness than the damping effects. The variation pattern of the dynamic impedance against the modulus of layered soil is dominated by the cut-off frequency. Particularly, in Gibson soil, the stiffer surface soil yields the greater pile-head stiffness. The dynamic stiffness of piles in Gibson soil could be approximated by two or more soil layers with equivalent Young's modulus. [ABSTRACT FROM AUTHOR]

The aim of this present paper is to provide lower bound bearing capacity factor Nc for axially loaded circular piles in clays by using two-dimensional finite elements and the three-dimensional non-linear Tresca yield criterion. The clay layer is assumed to be completely saturated and subjected to undrained loading. The edge discontinuities of the Tresca surface was smoothened by providing a C2 rounded surface at the vicinity of the sharp corners of the regular hexagon lying on the octahedral plane. No inherent assumption of hoop stress was considered in the present analysis. The clay has been considered to be heterogeneous where the cohesion increases linearly with depth. The study is useful in providing the methodology for simulating the axisymmetric structures and providing the design chart for the bearing capacity factors for circular piles in clays whose cohesion increases linearly with depth. [ABSTRACT FROM AUTHOR]

• V-H-M failure envelopes and failure mechanisms of tripod pile foundations are identified considering a bunch of practical factors. • The direction of loading plane affects both the size and the location of the failure envelope in loading space for the tripod pile configuration. • An empirical design approach is proposed to predict the failure envelopes of tripod pile foundations in the 3D V-H-M space which will be helpful for engineering practice. The problem considered in this computational study is for the bearing capacity determination of three-dimensional (3D) rigid tripod-pile groups subjected to combined vertical (V), horizontal (H), and bending moment (M) loads. Using the adaptive 3D finite element limit analysis (FELA) coupled with lower bound, upper bound and mixed Gauss element formulations, numerical results are compared with those of the previous study under a single-component loading (V , or H, or M). The failure envelope in the 3D V – H – M loading space is then constructed, and several failure mechanisms presented to complement the discussions on the complex 3D responses. This is followed by a parametric study for the various factors such as the pile length, pile spacing, pile-soil adhesion factors as well as the loading direction angle. Finally, a closed-form design expression of failure envelopes considering the abovementioned influential parameters and the combined load are derived. Noting that the current industry-based design procedures for tripod-pile groups are rarely found, the outcome of the present study can be used with great confidence in design practice. [ABSTRACT FROM AUTHOR]

A new model for laterally loaded piles is proposed, consisting of a linear part and a non-linear iterative part. The linear part is based on the Green's function method, which strictly satisfies the displacement and stress continuity conditions at the pile-soil interface and leads to a rigorous solution. The non-linear iterative part assumes that the shear modulus of the soil around the pile decreases with the average strain of the soil layer. Only two soil parameters need to be calibrated, including the initial shear modulus of the soil and the reference shear strain at half the initial modulus. Compared to the finite element model, the advantage of this model is that it converges quickly while maintaining accuracy, which greatly improves computational efficiency. The advantage of this model over the p-y curve model is that it does not have the difficulty of selecting p-y spring parameters, especially for monopiles. The accuracy of this model is verified by comparison with three-dimensional finite element models and nine existing studies, including numerical models, field tests and centrifuge tests. These cases cover various piles with diameters of D∼0.273–10 m and aspect ratios of L/D∼3–40, installed in sand or clay by driving, jacking or vibration. • A new model for laterally loaded piles is proposed. • Only two soil parameters need to be calibrated in the model. • The model is suitable for piles of any aspect ratio in both clay and sandy soils. • The accuracy of the model is similar to that of the FEM model. • The computation time is comparable to the p-y curve model. [ABSTRACT FROM AUTHOR]

At some coastal areas in Egypt, especially Port Said and Damietta, there are layers of loose to medium silty sand with traces of seashells fragments at the surface, overlying a very deep soft clay layer. The construction of shallow foundations over such soil formation is difficult and in some cases is not possible due to the high soil compressibility, large settlements, low bearing capacity, and near surface groundwater. In such case, small diameter piles could be used especially under low rise structures to transmit the structure loads with much lower settlements. A finite element-based numerical analysis using ADINA software (Version 9.4.2) ‎[4] is used to analyze and study the behavior of piles in such soil formations. Results indicated that both pile diameter and embedded length in loose sand have significant effect on the pile capacity and settlement on the other hand pile embedded length in soft clay layer has no effect on either pile capacity or pile settlement. One of the key findings of this study is that, most of the load carried by the pile transmitted to soil by skin friction so that, the choice of using pile foundation in such soil formations is practical to some extent.

Abstract The steel-concrete composite sections are often used in civil building in Brazil and around the world. The connection of the steel profile and the concrete slab increases the performance of the composite structural element due to the use of the advantages of each material. In this article, a bar element is used with an interface element for nonlinear analysis of steel-concrete composite beams with partial interaction. The objective is to develop an algorithm that uses this analysis tool to design steel-concrete composite beams looking for project optimized in terms of material costs. Defined spans, supports, ultimate and service load, an optimization algorithm is used to define the dimensions of the rectangular cross section of the concrete slab, I-shaped steel profile, and the reinforcement bars of the concrete slab, so that the quantity of these materials are the minimum to ensure structural safety, considering the ultimate and service limit states. The design constraints are obtained from building code requirements for concrete, steel and composite structures. The objective function is defined as the cost per unit length of the composite beam, obtained from the unit cost of each material, steel, concrete and reinforcement. In the optimization process, the iterative method sequential linear programming is used, in which the nonlinear problem is approximated by a sequence of linear problems, which has its optimum point defined step by step by the Simplex method. Examples of composite beams with ultimate loads defined in the literature were used to validate the implementations. Other examples were analyzed, being evaluated at each iteration the restrictions and objective function to verify the efficiency of the algorithm.

Abstract Low strain integrity tests in piles are relatively cheap, of quick execution and nondestructive. Despite all these advantages, several variables are involved and the influence of external factors can complicate the interpretation of the results. Between them, the influence of the pile reinforcement can be high lighted. In piles partially reinforced, the difference in density and elastic modulus of the concrete in different parts of the pile and the influence of the process of introducing the reinforcement bars can induce some reflections in the test that can be confused with damage in the pile and, therefore, should be taken into account to analyze the tests results. In this research, the influence of the reinforcement embedded in the piles is analyzed using numerical (FEM) simulations and comparing them with tests made in the field. A new classification of possible damages is proposed based on the analysis of the reflections observed at the end of the reinforcement cage embedded in a pile partially reinforced.

Tunnel construction below or adjacent to piles will affect the performance and eventually the stability of piles due to ground deformation resulting in the movement of piles and changes in the axial force distribution along the piles. A three dimensional finite element analysis using PLAXIS 3D (2013) was performed to study the behaviour of a single pile and 3 x 3 piles group during the advancement of shield tunnelling in ground. The 10-node tetrahedral elements were used to model both the soil and the tunnel lining. The Hardening Soil (HS) model was used to simulate the soil structure interaction at the tunnel-soil interface. An isotropic elastic model was used for the pile, piles cap, tunnel lining and tunnel boring machine shield (TBM). Several parametric studies were attempted including the longitudinal, lateral, and vertical tunnel location relative to pile embedded in different types of soil (clay or sand). The results showed that the pile head settlement increases during the tunnelling advancement in larger values than that for ground surface settlement. A zone of influence was determined in the range of twice the tunnel diameter in the longitudinal direction (forward and backward of the pile), and transverse direction (left and right of the tunnel centreline). If the tunnel boring is kept off this zone then there is no fear of pile collapse.

ABSTRACT Wind solicitations generate horizontal, tensile, and compressive stresses on building foundations. In empty light structures, such as agricultural greenhouses and, in the specific case of silos and elevated structures such as metal water tanks, the consideration of these loads becomes important because the lack of the weight component due to the storage load significantly influences the balance of forces. This study focused on the behavior of metallic steel profiles, aiming at its application as a foundation element for the pile, considering the soil of Diabasic origin common to the Center-South region of Brazil. Load tests in real scale were carried out on three steel profiles, type I, gauge W 250 mm x 32.7 kg m-1, drilled in the ground up to 12m deep by means of a pile driver. One steel profile was submitted to lateral loading, another to vertical compressive loading, and the other to vertical tensile load. Test results determined the bearing load of the pile for each loading type, calculated the soil reaction coefficient for lateral loading, and verified the applicability of load capacity prediction methods to tensile and compressive strengths of piles, commonly used in foundation projects.

Low strain integrity testing for pile quality control, based on the analysis of elastic waves, is one of the most common methods, due to its high efficiency. However, it also has a number of limitations that should be taken into account during pile testing. For additional study of the method and its effectiveness, an experimental site was constructed, consisting of ten cast-in-place piles with embedded defects. When analyzing field data, pile defects were not identified. For further analysis of the problem, as well as for interpreting the results and identifying pile defects, a cluster analysis method, the so-called ANN-classifier, is proposed. This paper describes the results of creating an algorithm for the recognition of defects and their localization in cast-in-place piles. It is proposed that use of the characteristic points of the spectrum of the signal as the input vector of the ANN classifier, and the type of pile defect as the output vector, is optimal. The results of the study led to the conclusion that the ANN-classifier can be used as the main tool for automatic interpretation of the results obtained by low strain integrity testing.

The difficulties with the application of low strain integrity testing for evaluating the length of driven precast piles of two sections justify the need for new data acquisition and analysis techniques. The standard time domain analysis of the recorded signals may not allow for distinguishing the desired responses from a pile toe and a splice. In this paper, we propose the use of a set of hammers of different weights and tip materials that will provide various sensitivities of the test to a pile splice. To further analyze the collected data, we study the distributions of phase angles obtained using complex continuous wavelet transform. The characteristic phase shifts that distribute from higher to lower frequencies can be interpreted as responses from a pile toe and a splice. To verify the proposed approaches, a series of numerical simulations were performed using the finite element method for the driven pile models with the different properties of a splice zone. Numerical simulation results show that the pile splices are clearly identified when using the shorter input pulses which can be generated by light hammers with a hard head material. The total length of a simulated pile with a 1 mm air gap between sections was undetectable by standard data analysis approaches and was evaluated when analyzing the wavelet phase angle distributions. Numerically validated data acquisition and analysis techniques were applied to field data analysis and allowed us to confidently identify the length of two-section piles grouped with a pile cap.

Firebrands are known to cause ignition of structures far from the primary fire front, resulting in significant damage to structures before firefighting can be attempted. To make structures more resilient to firebrand ignition, a better understanding of the heat transfer from firebrands to surfaces is needed. This paper provides a statistical assessment of different factors expected to have an impact on the heat flux from firebrand piles to a flat surface. The factors included in the study were wood moisture content, wood type (hardwood or softwood), wood density, wood state (live, dead, or artificial), wind speed, pile mass, firebrand diameter, and firebrand length. Using design of experiments, test matrices were developed that permitted a statistical analysis to be performed on the data. This statistical analysis was used to quantify which factors had a statistically significant impact on the heat flux from the pile as well as ranking the importance of the different factors. Artificial firebrands were found to have statistically higher heat fluxes compared with natural firebrands. Other factors that had a statistically significant impact on the heat flux were wind speed, firebrand length, and firebrand length-diameter interaction. Firebrand aspect ratio (related to the firebrand length-diameter interaction) is directly related to the pile porosity, which is a measure of the volume of air in the pile. Increasing the aspect ratio (which increases the pile porosity) results in higher heat fluxes across a larger region of the pile and was found to be an important factor. Firebrand diameter and pile mass were found to affect the burning duration but not as significantly as other parameters. The number of firebrands in the pile was also observed to potentially affect the heat flux, with a critical number required to reach the highest heat flux for a given firebrand geometry.

A probabilistic analysis approach for estimating the durability of piles with microcracks under chloride attack is presented. The chloride ingress model is obtained by considering the time-dependent diffusion process. The equivalent diffusion coefficient is derived to investigate the crack effect by introducing the crack effect factor. The fitting formula between the chloride diffusion coefficients and crack widths is established through experimental results, and the proposed equivalent diffusion coefficient is verified by comparison with the experimental results. The probabilistic evaluation of durability of piles with microcracks is performed, and then the parametric analysis is performed to study the effect of main parameters on the failure probability and durability life. The results indicate that the chloride concentration increases rapidly as the crack width increases at the same number of cracks. The durability life greatly reduces with increasing crack density of pile. The durability life predicted by probabilistic method is always less than those by deterministic method at the same condition. The deterministic approach may underestimate the threat of reinforcement corrosion induced by chloride attack, owing to the omission of probabilistic nature of main influencing parameters. [ABSTRACT FROM AUTHOR]

Herein, an experimental investigation of the plugging impact on the capacity of open-ended piles installed in clayey soil is presented. Model tests involving static axial compression load tests are carried out on four open-ended modeled piles with different diameters (12.5, 19, 25, and 50 mm). In the same manner, four closed-ended modeled piles are tested to make a comparison. A load cell system is used to determine the resistance acting on the piles, with an instrumented transducer on the outside walls of the pile. The eight steel model piles are tested in the circular steel tank with a diameter of 350 mm and 400 mm in length. Three undrained shear strengths of the clay sample, 5 KPa, 10 kPa, and 18 kPa, are used in model tests. The outcomes of the tested models uncover that the pipe pile capacity is mainly mobilized at the low shear strength. In addition, it is realized that the soil plugging in the small diameter has an impact on pipe pile capacity. Based on experimental results, five statistical models are established to achieve relations between the maximum load for the closed-ended pipe. It is realized that the value of Qexp is highly correlated with the diameter and Qcalc.. [ABSTRACT FROM AUTHOR]

Background: As there is controversy and disagreement with respect to treatment of Haemorrhoids adopted by conventional method due to inefficacy, relapse and complications are seen. It is most prevalent ailments and impacts the quality of life significantly. Haemorrhoids are enlarged, swollen veins around the anus externally or in lower rectum1. This study aim to access Role of Sulphur in Cases of Haemorrhoids as a constitutional2,3, medicine follow well2,3, anti miasmatic5,6. The Study showed near about 100% of cases responded to Sulphur4,5, thus proving effective role of Sulphur in Haemorrhoids. The study aim role of Sulphur in Haemorrhoids. A minimum of 1 year and 15 to 70 yrs of age and six matched controls were included in the study. As there is controversy and disagreement with respect to treatment of Hamorrhoids adopted by conventional method due to inefficacy relapse and complications are seen. It is most prevalent ailments and impacts the quality of life significantly. Haemorrhoids are enlarged, swollen veins around the anus externally or in lower rectum1. Material And Methods: Here patients were subjected on clinical presentation and examination using standard scales measuring severity and anoscopy. The entire process was done using standard case research record with a follow up of minimum 3 months period. Result: Out of 30 patients screened, it was observed that 66.6% of affected patient were in age group of 25-40, 16.7% in 41-54. Males prevalency was present and in that 26.6% were service class, driver 13.3% and mechanics 13.3%. Showing occupation played a significant role. The study should 100% of cases responded to sulphur as a constitutional medicine in 23.3% cases, as a follows well cases in 60%. Conclusion: Hence we conclude that along with Homoeopthic medication used as constitutional, follow well, Dietary corrections, correction of sedentary habits by exercise etc. Which are the predisposing factors is also mandatory. [ABSTRACT FROM AUTHOR]

Static and dynamic behavior of above-ground steel storage oil tanks resting on end bearing piles or stone columns are studied and analyzed using ADINA (2019) program. The studied soil profile is an upper soft clay soil layer, followed by an extended dense sand layer. The main purpose of this research is to explore to what extent stone columns can be used as an effective alternative to concrete piles under steel storage tanks. Therefore, many three-dimensional numerical models are conducted to analyze and study the performance of such tanks in both static and dynamic cases. Ten of the studied cases are steel tanks resting over stone columns with different numbers and properties. On other hand, one model studied the behavior of steel tank resting on large diameter concrete piles. Results indicate that stone columns can be used instead of end bearing piles as long as the computed settlements are safe. In addition, stone columns are behaving better than concrete piles in decreasing of hoop stress in tank shell. It is also noticed that stone columns with high elastic modulus are effective in reducing the sloshing height of the oil surface during earthquakes. [ABSTRACT FROM AUTHOR]

Laboratory measurements were done of the end-bearing and side-shear stresses on small piles subjected to “static” and rapid load tests. Interpretation, by the unloading-point method, of the results of rapid tests were done to estimate what the behaviour under a static test would have been if it had been done instead. Comparisons were made of the estimated static test behaviour to the actual static test behaviour to determine empirical values of a factor to adjust estimates closer to actual static test results. The dependence of the empirical factor on soil type, the liquid limit of plastic soils and water content is shown. [ABSTRACT FROM AUTHOR]