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Stone columns are constructed using stone aggregates of typical size ranging from 15 to 75 mm. Alternatively, building debris and shredded tyre chips can be used to replace the stone aggregates either partially or totally, which can be an environment-friendly solution to the disposal of solid waste materials. This paper presents the results of model tests on ordinary floating stone columns (OSC) and encased floating stone columns (ESC) constructed with a mixture of stone aggregates and shredded tyre chips. Tyre chips of 10 mm size, 2 to 3 mm thick after removing steel wires, were used in this study. Large size direct shear tests were also conducted for different mix proportions of tyre chips and stone aggregates to assess their shear strength properties. Model tests were conducted on ordinary and encased floating stone columns of diameter (d) 100 mm and l/d ratio of 4.5. Loading was applied through hydraulic jack and reaction loading frame. Model test results show that an ordinary stone column made of stone aggregates can be replaced by an encased stone column made of 100% tyre chips. This confirms the possibility of either partial or full replacement of stone aggregates with tyre chips in stone columns.

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Static and dynamic lateral load tests were carried out on model aluminium single piles embedded in soft clay to study its bending behaviour. Model aluminium piles with length to diameter ratios of 10, 20, 30 and 40 were used. Static lateral load tests were conducted on piles by rope and pulley arrangement upto failure and load-deflection curves were obtained. Dynamic lateral load tests were carried out for different magnitudes of load ranging from 7 to 30 N at wide range of frequencies from 2 to 50 Hz. The load transferred to the pile, pile head displacement and the strain variation along the pile length were measured using a Data Acquisition System. Safe static lateral load capacity for all piles is interpreted from load-deflection curves. Dynamic characteristics of the soil-pile system were arrived from the acquired experimental data. The soil-pile system behaves predominantly in nonlinear fashion even at low frequency under dynamic load. The displacement amplitude under dynamic load is magnified by 4.5-6.5 times the static deflection for all piles embedded in soft clay. But, the peak magnification factor reduces with an increase in the magnitude of lateral load mainly because of increase of hysteretic damping at very soft consistency. The maximum BM occurs at the fundamental frequency of the soilpile system. Even the lower part of the pile affects the pile head response to the inertial load applied at the pile head. The maximum dynamic BM is magnified by about 1.5 times the maximum static BM for model piles in tested consistency of clay. The maximum dynamic BM occurs at a depth of about 1.5 times the depth of maximum static BM for model piles, which indicates an increase of active pile length under dynamic load.

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