International Journal of Civil Engineering
Volume:14 Issue: 7, 2016

Pile penetration and rebound amount measurements during pile driving are important to assess penetration and bearing characteristics and to guarantee assurance of pile installation. Traditional manual measurement method of penetration and rebound of piles exposes engineers under unfavorable environment of injury risk and significant vibration and noise. To improve the accuracy of pile penetration and rebound measurements and to ensure safety of engineers during pile driving, the close-range photogrammetry approach was implemented by taking a series of stereo-pair images on a pile using two charge coupled device cameras. From the field implementation, it was found that the newly developed pile penetration and rebound measurement system is accurate, safe, and convenient.

The main purpose of this study is to investigate the influence of urban solid waste leachate on the mechanical properties of soil. To provide a more accurate identification of the contaminated soils, cylindrical specimens of the soil, according to the density curves with different initial conditions (different initial contamination levels) were prepared, then the soil specimens were loaded at different load levels using a direct shear testing equipment and a universal testing machine to apply axial compression on the specimens. Results for the stress–strain and failure behavior of the soil specimens containing different percentages of the solid waste leachate were evaluated. The most important result was reducing the mechanical properties of the soil contaminated with different percentages of solid waste. The addition of lower quantities of leachate gave far more significant results compared to the addition of higher amounts of leachate.

In the present research, an analytical method is applied to determine the bearing capacity of strip footing on two layers of soil. Bearing capacity is calculated according to soil resistance beneath the foundation and a virtual retaining wall method. To determine the bearing capacity of the footing in the said method, the active and passive forces on the retaining wall are considered equal along the edges. The active and passive forces of each of the two soil layers are found, and the results are applied to calculate the footing bearing capacity. Among the many advantages of this method are the possibility to determine depth of the rupture surface beneath the footing, and the ability to study the effects of the soil’s second layer on the footing bearing capacity. This study also examines the effects of soil improvement beneath the footing, as well as the depth and width of the compacted area on bearing capacity. A thorough analysis is conducted on soil layer thickness, soil cohesion and friction angle, footing depth and width, the width of the compacted soil beneath the footing, and the depth of underground water. A MATLAB program was used for calculation and deduction. In order to study the effects of various parameters on two layers of soil, results were compared with the bearing capacity of the footing on one soil layer in various situations. The bearing capacity of the footing was then compared with previous experimental methods, and the results obtained were reliable.

The main objective of this study is to analyze the use of plastic waste materials for the reinforcement of clayey soils. An experimental study was conducted to investigate the compressibility and undrained shear behavior of clayey soil mixed with plastic waste. Clayey soil was mixed with various amounts of plastic waste (i.e.; 0, 0.5, 1.0, 1.5 and 3.0 % in dry weight) and soil compaction, consolidated undrained triaxial and oedometer consolidation tests were performed on the mixtures to study the effects of plastic waste, plastic flexibility, confining pressure and initial density on clayey soil behavior. According to the results, plastic wastes do not affect the compaction characteristics of clayey soil considerably. The addition of plastic wastes that exceed a specific value (i.e., 1.0 % in this research) changes the undrained behavior of samples from contractive to dilative. The addition of plastic wastes beyond 1.0 % improves shear strength and reduces compressibility of the clay. Increasing rate in shear strength and decreasing rate in compressibility depends on the confining pressure, flexibility of plastic and the initial density of the samples. The rate of increasing or decreasing is more noticeable when plastic rigidity, initial density and confining pressures are relatively high. Moreover, plastic waste has negative effects on the free swelling, swelling pressure and swelling index of samples; such parameters are therefore higher in plastic waste mixed clay than the associated values of plain clay.

The relative performance of two soils as a sustainable material to attenuate the transport of heavy metal ions, cadmium (Cd2) and nickel (Ni2), from aqueous solutions has been evaluated. Red earth soil (RS) and black cotton soil (BCS) originating from India, were selected, and batch equilibrium tests including sorption kinetics and leaching studies were conducted. Langmuir isotherm was found to be more suitable than Freundlich isotherm for both the soils. Kinetic data were fitted on four models namely pseudo first order, pseudo second order, Elovich and intraparticle diffusion. Correlation coefficients obtained by all models fitted well in the following ranking: Elovich > Intraparticle diffusion > pseudo second order > pseudo first order. Based on extensive experimental data, it is concluded that the ranking on sorption was of the order Cd > Ni for both the soils, and BCS exhibited relatively higher retention levels compared to RS. It is further concluded that BCS can be used as a substitute to filter material, RS a substitute to main liner material in attenuating Cd2 and Ni2 from an industrial landfill leachate.