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Due to urbanization, there is a large increase in industries; these industries produce effluent. This effluent will alter the physical and chemical characteristics of the soil and water. A laboratory study was attempted to understand its physiochemical change in soil and water through a column study: it was conducted under the variable head condition for two different soils (in situ and sandy soil) and four different wastewater samples (RO water, treated and untreated municipal water, untreated industrial wastewater) for one cycle. The time taken for sandy soil is 3 h, and for in situ soil, it is around 6 days. The pH, specific gravity, conductivity, permeability and shear strength properties were all studied. There was not much change in the chemical properties of the water upon passing it through the column medium. But the soil contaminated with untreated wastewater shows a reduction in bearing capacity by almost 50%, making it unfit for construction.

Pile, deep foundation undergo large vertical, lateral and compression load. The behaviour of the pile in the levelled terrain for all possible conditions is well studied. The pile can be placed in man-made or natural slope, where there is a lateral- capacity reduces. This condition is predominately seen in off-shore and embankment areas. The study gives a detailed view in understanding the influence of geometry of slope in lateral capacity of pile done by various researchers.

The purpose of dam is to store water and supply to nearby required area. The underestimated capacity, overtopping, erosion in the downstream side, geometry of the slope, sliding, high settlement, etc., are the causes of dam failure. The dam failure occurs both nationally and internationally leading to a pressing need to fathom the underlying causes for the failure and to minimize such occurrences. To understand the causes of failure, it is important to investigate the dam profile and properties. This paper primarily focuses on the major reasons for the dam failures such as overtopping, erosions, seepage, and seismic factors which also includes the details of dam and reservoirs. Thus, the paper is concluded with the lessons and practices understood from the various cases to avoid the failures in the near future.

The shallow foundation has opted when the required bearing capacity is at shallow depth. In case if the location of the structure is susceptible to an earthquake, hypar shell foundation can be used instead of going for a special type of foundation. In this paper, a 2D FEM analysis is done to understand the settlement behaviour of the hypar foundation in sandy soil and it is compared with flat slab behaviour. From the analysis, it is believed that hypar foundation can withstand static load. Simulating the earthquake to the hypar foundation reduces the settlement compared to the flat slab by 23.63%.

The presence of pile in natural or man-made slope is a common scenario. The effect of the active pile in a stable slope becomes void when it is moved away to a maximum distance of 5R (R-relative stiffness factor) from the crest of the slope towards the embankment under lateral load. In this paper, a numerical study is made to understand the development of stress zones around the pile when it is kept in a soil slope of 1 V:3H; the shear strength is maintained as 30 kPa. A prescribed displacement (5 mm) is applied at the pile head and the lateral load corresponding to it at varied position from the slope crest towards the embankment is studied. The slope effect becomes zero when the lateral load capacity of a single pile at a varied position from the slope crest is equal to the lateral load at horizontal ground. Until zero slope effect, the pile is moved, and the stress zone formed around the pile is studied.

Pipe bridges are structures that play an indispensable role in chemical and oil plants. They support cable trays or pipe-carrying material. This study aims to identify the ideal configuration of a pipe bridge through the comparative study of girders with drop hanger and truss arrangements for three different spans. The most efficient arrangement for each span was suitably identified. Through the analysis carried out, it was then identified that the Girder arrangement is suitable for smaller spans such as 15 meters; while the truss arrangement was preferable for longer spans.

An experimental study was proposed to understand the behaviour of single pile in sloping ground with various eccentricity. Cohesionless soil was used for conducting experiments with a horizontal ground and with a slope of 1V:2H. With calculated stiffness factor (T) as 92 mm, the eccentricity was varied as 0T, 0.5T and 1T. The lateral capacity of the pile in horizontal and sloping ground condition decreases with increase in eccentricity; the increase in lateral capacity was linear too. The bending moment increases with increase in load; but the depth of maximum bending moment was 0.15 m for 0T and 0.5T of eccentricity. For 1T of eccentricity, the depth of maximum bending moment varied to 0.07 m from the point of load. An equation was proposed to calculate the maximum bending moment of the pile for any eccentricity for a slope of 1V:2H, which is the governing factor for pile designing.

This paper presents the study of single pile in the sloping ground under different static lateral loading conditions in which the pile is subjected to forward and reverse loading at ground level and slope level. Laboratory experiments are conducted in a test tank with cohesive soil by embedding a semi-infinite pile. The behaviour of the pile is studied by considering three different slopes (1V:3H, 1V:2.5H and 1V:2H) with varying positioning of pile in-terms of relative stiffness factor (R). Relative stiffness is found by conducting lateral load test in horizontal ground condition for the same soil properties. Lateral load corresponding to 5 mm displacement is taken as the ultimate lateral load. The deformation and bending characteristics of the pile are observed for different conditions and compared with pile loaded at the levelled ground. Numerical studies are performed to validate the test results and to assess the effect of water table on pile-slope behaviour. Parameters such as optimum distance from slope crest towards the embankment where the effect of slope becomes void are also studied.

Purpose This paper aims to understand the incorporation of sustainability methods of construction through the study of a low-cost housing Tamil Nadu Housing Board settlement in a locality in Chennai, India. Such a study helps to arrive at proper design decisions and incorporate a participatory approach involving the residents to enable the developers, here the decision-makers of the government, cater to the local interests. Design/methodology/approach First, a survey was conducted to understand the local conditions and people’s aspirations. Along with this, the parameters pertaining to a green housing were derived and compared with the needs of the locals, to arrive at the most influencing parameters by decision-making trial and evaluation laboratory model (DEMATEL) analysis. Findings The study finds that parameters viz. “ensuring basic services” and “social inclusivity” happen to be the causal factors that seem to influence the needs of the locals. These factors therefore can guide the future plans to redevelop the settlement or construct similar settlements in a more sustainable way. Originality/value This paper is a unique study to combine the twin pillars of low-cost housing and sustainability, which helps in developing settlements that are conducive to the city’s socio-developmental requirements as well as respectful of the natural environment. Further, the analysis conducted through DEMATEL method could essentially guide the decision-maker to tackle urban challenges in the most locally suitable and sustainable approach.

An experimental study was carried out to understand the behaviour of a laterally loaded single pile on a slope with different length/diameter (L/D) ratios driven into cohesionless soil for a relative density of 70%. Static loading was applied in both forward and reverse directions for slopes of 1V:1.5H, 1V:2H, and 1V:2.5H for a constant L/D ratio representing flexible pile behaviour. It was observed that the load ratio (load on a sandy slope to the horizontal ground) decreased with an increase in the slope’s angle. The post-static behaviour of the pile under the same conditions was also studied to evaluate the elastic displacement, which increased with an increase in the slope’s angle. Due to the constant passive resistance under the reverse loading, the lateral load on the slope’s crest was almost equal to the horizontal ground’s condition. The effect of the L/D ratio was studied by varying the length and diameter and by maintaining the other parameter as a constant. The lateral load of a pile increased with an increase in its length and diameter.

Retaining wall is built to withstand the lateral pressure exerted by the soil from the slope and pave way for other construction in the rear side. The ideal backfill material are granular graded stone, gravel, clean sand with a small percentage of fines; such material is durable, strong and free draining. Due to the depletion of the natural available material, sustainable material are considered ad alternative material for the backfill. In order to understand the influence of a sustainable material as backfill a finite element analysis was carried. The chosen materials are copper slag and crumb rubber with soil in their optimum percentage. The soil mixed with copper slag was able to take make load with minimum displacement compared to soil and soil + crumb rubber. Soil + crumb rubber gives more displacement than that of virgin soil because of its cushion effect compared to soil+ copper slag.

Sand compaction pile (SCP) is a method to strengthen the soil to obtain more bearing strength. Upon stabilizing the soil using SCP, the foundation was constructed. SCP offers more resistance in the case of soils suspectable to seismic and liquefaction actions. SCP is a 50-year-old technique that can be used in all soil types. The study presents classification on compaction or strengthening methods and recommendations obtained from the referenced papers. This paper also provides different types and methodologies adopted for the installation of the SCP, and various applications of SCP.

In the current scenario, there is an increase in demand for construction land. To overcome the need of land for construction, feeble soil should be stabilised. The soil strength can be increased by means of altering the strength of the soil through physical or chemical stabilisation. One such physical stabilisation technique is making the ground composite with sand compaction piles. To minimise the utilisation of sand in the compaction pile, copper slag, recycled material is used as a partial replacement material. The load-penetration behaviour of soil without and with compaction pile was studied in the laboratory by conducting tests in CBR mould. Fifty percent of sand was replaced by copper slag and a compaction pile was installed, and its corresponding behaviour was studied.

A well-planned and socially inclusive city provides an unprecedented opportunity to transform its challenges like urbanization, management of infrastructure, etc. to a smooth sustainable transformation. The implementation a material technology like Glass Fibre Reinforced Gypsum (GFRG) in construction also links itself to the important Sustainable Development of providing affordable housing for all (besides its other possible applications). This technology involve greater thought in planning and rapid construction of quality eco-friendly homes. Thus, weighing the advantages, uses, and shortcomings of this gypsum composite material through key governing attributes, the technical, economic, and social implications of this perspective solution for mainstream construction challenges were theoretically discussed. Further, the reasons for its limited practice in the Indian industry, user satisfaction, and challenges in the incorporation of this technology were also studied and compared with the conventional methods of construction in our point of view.

The reuse of waste material is becoming an emerging thrust area in Civil Engineering. Crumb rubber produced in abundant worldwide is reused in concrete, pavements, sports field, etc. The influence of crumb rubber, when mixed with highly compressible and inorganic clay, shows significant influence in its compaction characteristics under light compaction. Various proportions of crumb rubber were added namely 10,15,20,30,40 and 50% by weight and tested to understand its compaction characteristics. The behaviour of wet and dry of optimum side of modified soil with various percentages of crumb rubber was discussed. A model is generated to calculate the maximum dry density of the modified clay.

The capacity of laterally loaded piles is mainly governed by the strength of soil at the proximity of top level of the piles. In coastal areas, the topsoil mostly comprises of soft clay and they extend for a considerable depth, offering low resistance against lateral loads. In addition to static loads, the piles are subjected to cyclic loads. Experimental study of single pile and pile group for varying L/D ratios, number of piles in a group and spacing between the piles under static and cyclic lateral load is studied. Cyclic lateral load tests were conducted for L/D ratios of 12, 18 and 24 under cyclic load ratio of 0.6. Cyclic load tests were performed by embedding the piles in a clay bed of consistency 0.2. The experimental results showed that for pile of L/D ratios the 12, 18 and 24 displacement at pile head becomes nearly constant after 300 hundred cycles. From the pattern of displacement versus number of cycles, it is observed that shorter piles exhibit higher magnitudes of displacement compared to longer piles upon cyclic loading. However, longer piles show higher rate of increase in displacement with number of cycles compared to shorter piles.

This investigational study involves analysis of settlement characteristics of HYPAR shell footings with variation in the edge beam sizes using a finite element code-PLAXIS. HYPAR shell footings have been known to bring about economy in regions with high material to cost ratio when compared to flat slab footings. This study strengthens the case of HYPAR footings by confirming its superiority in the aspect of lower settlement characteristics. The effects of changing the embedment ratio on the aspect of settlement, load bearing and soil-shell interphase stresses have also been studied.

In present study, a new berthing structure is proposed for slope stable dredging activity. A slope with a weak soil structure comprising gravel, sand–silt clay, stiff silty clay, and terra firma at various depths is stabilized with ground improvement techniques. The pile makes dredging difficult for a single-slope angle. To overcome this difficulty, different slopes are recommended for different depths. This study analyses the slope stability for such a design by finite element modeling. Modeling shows that the factor of safety is > 1.5 for the varied slope structure, thus proving that the design is effective in preserving the slope stable.

Stone column is a ground improvement technique used to improve the bearing capacity and reduce the settlement of soft soils. It also serves as a vertical drain for accelerating the consolidation of clayey soil. The structure can be built over the column after stipulated period after levelling the soil with stone column with gravel. Laboratory tests were conducted on a clayey soil loaded uniformly in the CBR mould and the load-penetration behaviour was inferred. An initial numerical model was developed and the load penetration - curve was generated. Following this, the penetrations corresponding to 2.5 mm and 5 mm were studied. Finite element analysis was further carried out in order to understand the influence of diameter and friction angle of stone column on the bearing capacity using PLAXIS 2D analysis for a soil model.

The generation of crumb rubber is abundant in our country and safer disposal has become a challenging job. Hence, a study has been attempted by mixing the crumb rubber in two different types of soil (CI and CH) in different percentages and their properties were studied. They were mixed with the soil sample in 10, 15, 20, 30, 40 and 50%. The standard Proctor compaction, CBR, UCC and permeability tests were conducted. From the experiments conducted, it is observed that maximum dry density decreases with increase in optimum moisture content. The CBR and UCC value increases with increase in percentage of crumb rubber till 15% for both the type of soils and the coefficient of permeability increases with increase in percentage of crumb rubber.

Offshore mooring requires temporary foundations/anchors in water depths exceeding 1000 m. Suction anchors / piles are feasible and preferred solution in such large water depths and find widespread applications in the offshore oil industry. Suction anchors are large cylindrical (inverted bucket type) structure open at the bottom with a sharp cutting edge and closed at the top. Such foundations are placed on the seabed and allowed to penetrate under self-weight; the rest of the suction anchor is sunk into the seabed by pumping water from inside thereby creating a differential pressure on the inner side. National Institute of Ocean Technology (NIOT), Chennai, India proposes to install an offshore desalination plant at approximately 1000 m water depths. Also, mining of gas hydrates from greater water depths require mooring points. Suction anchors are considered as a suitable option for such mooring. Numerical modelling has been carried out using PLAXIS-3D for simulating the suction anchor behavior and estimating ultimate pull out capacity under various loading conditions and soil type. The validation of the model is done by comparing the results with field tests carried out at Royapuram fishing harbor. It is observed that the model conforms to the ultimate pullout load obtained from the field tests and hence can be used for estimation of pull out capacity of suction anchors at other location having different soil conditions.

Structures such as jetties, transmission towers, elevated highways and various industrial units are often supported by pile foundation on natural or man-made soil slope. The piles on slopes are subjected to lateral load from the super structure, earth pressure from the unstable soil, wave and current actions in case of marine structures, etc. The behaviour of a pile on sloping ground under lateral load is different from that on a horizontal ground. The aim of this paper is to experimentally and numerically evaluate the behaviour of a single pile in sloping clay layer subjected to lateral load. 1 g model tests are performed in laboratory test tank on instrumented pile embedded in clayey bed with varying slopes and shear strength. The behaviour of a single pile placed either at crest or at different distances from crest on slope is evaluated. Static lateral load was applied in a direction towards the downward slope. Numerical study comprise of 3-D finite element analysis using PLAXIS code. The input parameters used for the analysis were validated by comparing the PLAXIS results with the experimental result. A detailed parametric study was then carried out by varying the clay shear strength and the slope angle. Based on the analysis, non-dimensional design charts are prepared for lateral capacity in piles on sloping ground. A worked example is included demonstrating the use of the design charts for pile on clay slope subjected to lateral loading. � 2012 Indian Geotechnical Society.