Model tests on displacement field of internal soil induced by laterally loading pile

The internal soil deformation induced by a laterally loaded pile was analyzed using the transparent soil. The transparent soil was made of baked quartz and a pore fluid with a matching refractive index. An optical set-up consisted of two lasers, two digital cameras, a lateral load system, a model pile, a strain gauge testing instruments and a computer. A distinctive speckle pattern was generated by the interaction of the laser in transparent soil. Camera 1 was above the model box with its optical axis perpendicular to the ground surface set and Camera 2 was set in front of the model box with its optical axis perpendicular to the vertical profile. Two cameras were used to continuously capture a series of pictures of the transparent soil model induced by a laterally loaded pile. A set of laser speckle images obtained before and after the tests were used to calculate the relative displacement field. Two laser devices were used to illuminate different targeted sections close to the pile. Results illustrated that the soil displacements occurred near the ground surface in front of the pile. The influence zone in front of the pile decreased from 7.5 times pile diameter (D) to 6D and the maximum displacement decreased about 25% when the soil depth increased from 2.4D to 3.8D.