Evaluation of Coefficient of Permeability on Contaminated Granitic Residual Soil

This paper reports laboratory research carried out on natural and contaminated granitic residual soil from Covilha region （Portugal） to evaluate the coefficient of permeability in accordance with Darcy＇s law. The soils are contaminated with hydrocarbon （Benzene Toluene Etilbenzene and Xilenes elements） and leached of urban solid waste. The specimens remained saturated and the consolidation and swelling are substantially completed at different effective confining pressures （25 to 400 kPa） before the measurements are performed at different hydraulic gradient to determine the effect of the void ratio, fabric and contamination of soil.

Seepage-stress coupling constitutive model of anisotropic soft rock

To provide a seepage-stress coupling constitutive model that can directly describe the seepage-stress coupling relationship, a series of one-dimensional seepage-stress coupling tests on two kinds of soft rock (argillaceous siltstone and brown mudstone) were performed by using an MTS-815.02 tri-axial rock mechanics test system, with which the stress-strain curves according to the seepage variation were obtained. Based on the experimental results and by employing Hooke's law, the formulation of the coefficient of strain-dependent permeability was presented and introduced to establish a coupling model. In addition, the mathematical expression and the incremental formulation for coupling model were advanced, in which five parameters that can be respectively determined by using the experimental results were included. The calculated results show that the proposed coupling model is capable of simulating the stress-strain relationship with considering the seepage-stress coupling in the nonlinear elastic stage of two kinds of soft rock.

Geotechnical Perspective of the Causes of Cracks in Building of Univer­sity Campus(Sindh University Jamshoro Sindh Pakistan)

The building construction throughout world faces the defects from normal to heavy and destructive like cracks and fractures which cause damages and eventually collapses to heavy life losses alongside economical and financial.The cracks like structures are found in wall and columns also.For the aim of the study,the international experts have classified the minimum allowable standards of those defects which can not be harmful to buildings and other people living there.This research study has been administered to research the most reasons to research the causes of cracks during a newly completed and used buildings in where some distinct cracks appeared immediately and after some years.Often these cracks seem in almost in walls,columns,beams,and so-like structures having different patterns.the foremost useful and customary methods consisting of reconnaissance survey;building inspection and laboratory testing were wont to investigate the causes of those distinct cracks which will cause the formation of cracks were considered and analyzed by the utilization of reconnaissance survey,factors like width,pattern,and conditions of the cracks were identified during the building inspection stage and therefore the soil properties associated with the creation of cracks were determined during the laboratory test.supported the results of the study;there was no distinct evidence of things like a matured system which will cause the creation of cracks within the building;The pore water pressure during this sort of soil takes longer time to fade,which may be expressed by the very low value of the coefficient of permeability(1.90x 10-7 to 2.15 x 10-7 m/s)acquired from different soil samples collected from the study area.Hence the cracks during this sort of building were found to be caused by the settlement of the building thanks to the character of the predominant soil type that was found within the study area,all the cracks are active cracks with their width increasing with time and therefore the soils within the entire block of the building possessed high percentage of fine materials with high moisture content and plasticity indices.