TESTING APPARATUS AND TESTING METHOD FOR SIMULATING INFLUENCE OF CAVITY EXISTING ON PILE END ON BEARING PERFORMANCE OF PILE FOUNDATION

摘要

Disclosed in the present invention are a testing apparatus and testing method for simulating an influence of a cavity existing near a pile end on bearing performance of a pile foundation. The testing apparatus comprises a semicircular model box, an organic glass plate, a water injection system, a loading motor, and an industrial camera. According to the present invention, the water injection system is used to inject water into a sandy soil layer in the model box to simulate the case where an underground pipeline is broken and water overflows and the resulting case where a cavity appears in a soil layer; a control point and a mark point are provided in a sandy soil layer area, and the process of cavity formation and the displacement of sandy soil particles in the sandy soil layer during the loading process of a model pile are analyzed by means of the particle image velocimetry method and according to a photo taken by the industrial camera. The present invention has a reasonable structure and a simple operation, can be used for studying the influence of the cavity existing near the pile end on the bearing performance of the pile foundation, and the influence rule of different cavity positions and different cavity sizes on the bearing performance of the pile foundation, and provides an effective means for studying the influence of the cavity existing near the pile end on the bearing performance of the pile foundation.