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The first and fully validated smoothed particle hydrodynamics (SPH) model is presented to tackle coupled flow–deformation problems in unsaturated porous media that undergo large deformation and post-failure behaviour. Unlike the commonly adopted double-layer SPH framework for saturated soils, this paper presents a three-phase single-layer SPH model capable of predicting anisotropic seepage flows through porous media and their complete time-dependent transition from unsaturated to saturated states, as well as their influence on the mechanical behaviour of the porous media and vice versa. The mathematical framework is developed based on Biot's mixture theory and discretised using the authors' recently developed novel SPH approximation scheme for the second derivatives of a field quantity. The soil is modelled using a suction-dependent elastoplastic constitutive model, expressed in terms of effective stress and suction. In addition, an adaptive two-timescale scheme is proposed for the first time to address existing challenges in solving coupled-flow large-deformation problems that involve a significant difference in the timescale required for the solid and fluid phases. The capability of the proposed SPH model was demonstrated through fundamental consolidation tests and a large-scale rainfall-induced slope failure experiment. Very good agreements with theoretical solutions and experimental results are achieved, suggesting that the proposed SPH model can be readily extended to solve a wide range of large-scale geotechnical applications involving coupled unsaturated seepage–deformation problems. [ABSTRACT FROM AUTHOR]

The design of rock-socketed pile foundations requires careful consideration of critical construction aspects such as the socket roughness and smear for accurately estimating the shaft load capacity. Despite the effect of smear being investigated extensively over the years, previous studies are limited in accurately characterizing the effect of smear on the shaft response. This paper presents a comprehensive investigation on the load-bearing mechanisms of model smeared rock-socketed piles with different smear fabrics (configurations) at the pile-rock interface. These model piles were loaded into synthetic soft rocks while being intermittently subjected to three-dimensional (3D) X-ray computed tomography (CT) imaging. Interpretations from the X-ray CT images were correlated with the pile-head load-displacement behavior to gain insights into the load transfer attributes between the pile, smear, and rock. The various interactions between these components were deduced by monitoring the micromechanics at the pile-rock interface through shaft energy utilization, interface void volume, smear volume, and sand density mapping. Based on the observations, it was inferred that the load transfer between the smear and the rock is primarily dependent on the percentage and position of smear occupancy at the interface. Results indicated that for the partially smeared interfaces, the interface mechanics are a combination of smeared and clean shafts with the residual resistances dependent upon the combined compression of smear and rock debris at the interface. Moreover, it was observed that the continuous presence of smear for more than half area of the leading faces of the pile asperities results in the smeared regions of the pile taking precedence over the unsmeared regions in governing the load-carrying capacity of the shaft. The discussions presented in this study can provide a strong base to further study the smear effect, subsequently aiding in enhancing the existing design guidelines to economically construct piles in soft rock. [ABSTRACT FROM AUTHOR]

The primary aim of the present study was to propose a scale comprising factors that sensitize voters toward the political system and stimulate them for an active participation in the election process. More specifically, the study aimed to propose a scale for measuring political sensitivity of young Indian voters. For this purpose, the data was generated from the users of internet who fall in the age bracket of 18–29 years. The generated data was analyzed employing the statistical techniques such as exploratory factor analyses (EFA) and confirmatory factor analyses (CFA). Based on the study findings, a 9-item scale comprising three factors economic considerations, social considerations and perceived risk was proposed to capture political sensitivity of young Indian voters. This scale was named as Political Sensitivity Measurement (PSM). One interesting observation of the study was that the religious and caste consideration of young Indian voters was not important for motivating them for an active political participation. The study is pioneering in the sense that it initiates efforts for comprehensive analyses of the factors that inspire young Indian voters to participate in the election process. PSM will greatly help the academicians and researchers for an improved understanding of the Indian voters. The scale would also assist politicians in developing appropriate strategies. [ABSTRACT FROM AUTHOR]

Lime slurry pressure injection (LSPI) is a stabilization operation used in problematic soils by transportation industries with the aim of improving the geotechnical properties and bringing excessive maintenance costs to an acceptable standard. This paper presents detailed field and laboratory studies of a lime/fly ash stabilized site at Breeza, NSW, Australia. The mixing of slurry into the soil with depths was investigated by excavating a trench while the improvement of geotechnical properties was determined in detailed field and laboratory tests. Visual observations of the surfaces of an excavated trench showed slurry to be distributed within the shrinkage cracks in the desiccated upper soil horizon whereas slurry was conveyed through planes of hydraulic fracture in the soils at greater depths. Laboratory swell tests on the stabilized soils demonstrated a statistically significant reduction of the intrinsic swell properties in the upper horizon of highly plastic clayey soils by LSPI. A gain in soil strength was observed in cone penetrometer test soundings conducted in stabilized soils. Scanning electron microscope and x-ray diffraction studies proved the underlying physicochemical and cementitious reaction processes in stabilized soils. Aggregation of the soils was observed with the outward diffusion of calcium cations within proximity of slurry seams and resulted in a subdued shrink/swell propensity. DOI: 10.1061/(ASCE)GT.1943-5606.0000359 CE Database subject headings: Lime; Fly ash; Soil stabilization; Swelling material; Slurries. Author keywords: Lime; Fly ash; Mineralogy; Problematic soils; Soil improvement; Swell behavior.

An alternative method was introduced for predicting the nonlinear p-y curves for monotonic unidirectional laterally loaded single piles in uniform undrained clay. On the basis of numerical studies, closed-form solutions were developed for locating the start of yield ([y.sub.e]); the ultimate yield point ([y.sub.u]); and the initial stiffness, [K.sub.i] of the p-y curve. The nonlinear section of the curve between the start of the yield and the ultimate yield point was represented by Bezier polynomials (also known as de Casteljau's algorithm). Using these relationships, a direct method of constructing the p-y curves was presented considering either tension failure or no tension failure of soils. For a typical pile configuration, the resulting load-deflection response was observed to compare favorably with the predictions from FLAC analysis and Matlock. DOI: 10.1061/(ASCE)1090-0241(2010)136:1(265) CE Database subject headings: Pile foundations; Clays; Lateral loads; Theories.

An apparatus capable of testing subballast-subgrade filtration behavior under cyclic loading is presented. The apparatus can be used to accurately monitor the pressure fluctuations, permeability of the filtration system, and turbidity variations of the effluent with time. The test results show that the frequency of cyclic loading has an influence on the filtration behavior of subballast material used in railway tracks. Further, the effect of cyclic |oad on the design and selection of subballast materials over a wet subgrade must be considered to avoid filter malfunctioning. DOI: 10.1061/(ASCE)1090-0241(2007)133:3(338) CE Database subject headings: Filters; Laboratory equipment; Laboratory tests; Ballast; Railroad tracks.