Composite unit test device for rigid permeable pile composite foundation

Abstract

The invention relates to a composite unit test device for a rigid permeable pile composite foundation. A reaction frame detachably covers a top opening of a model box and is used for forming a closed space in the model box; a pile body enclosing plate structure is arranged on one side in the closed space, a saturated soft soil layer is arranged on the other side in the closed space, the top surface and the bottom surface of the pile body enclosing plate structure are in transmission connection with driving mechanisms, the two groups of driving mechanisms are used for jointly driving the pile body enclosing plate structure to reciprocate in the vertical direction, and axial force meters are arranged at the joints of the driving mechanisms and the pile body enclosing plate structure; and pressure applying devices are arranged at the top and the bottom of the saturated soft soil layer, after a pile body is arranged in the pile body enclosing plate structure, the side face of the side, close to the saturated soft soil layer, of the pile body makes close contact with the saturated soft soil layer, and the inner space of the pile body enclosing plate structure communicates with a water collector through a guide pipe. The composite unit test device takes the single pile reinforcement range of the rigid drainage pile composite foundation as a research object, and can simulate the stress state, the radial drainage condition and the pile-soil interaction in a composite unit.

Description

technical field [0001] The invention relates to the technical field of geotechnical engineering foundation treatment, in particular to a composite unit test device for a rigid permeable pile composite foundation. Background technique [0002] The research methods of model test in geotechnical engineering mainly include field test, constant gravity field (1g) small-scale indoor model test and centrifugal model test. Field tests provide important data support for theoretical research, but limited by cost and unique working conditions, it is difficult to do control variable research. The self-gravity stress field has a great influence on geotechnical engineering problems. The geotechnical centrifugal model test can use the centrifugal gravity field to construct a stress state equal to the prototype in the scaled-down model, but it has high requirements for equipment platforms, high test costs, and limited resources. The scaled-down 1g model has obvious economic advantages and ...

AI Technical Summary

Problems solved by technology

However, the stress level of the 1g small model is often far lower than the actual working conditions, which cannot reasonably simulate the ground stress, and usually does not satisfy the similarity principle. The qualitative attributes of the test results exceed the quantitative attributes, so they cannot be used to quantitatively evaluate the real situation of the project. and generally cannot be directly used to guide production practice

The boundary conditions of conventional soil mechanics unit tests such as compression consolidation test and triaxial shear test are determined and controllable, and reliable test data can be obtained, but traditional unit tests are only for homogeneous units with determined stress state, stress history and boundary conditions Soil samples, unable to reflect the stress-strain relationship of the pile-soil composite unit in the composite foundation

Images