关键词: 装配式, 地下连续墙, 沉桩阻力, 预制桩, 模型试验, 泥浆浮力

Abstract: Prefabricated diaphragm wall is constructed through factory prefabrication and site jacking, which is more civilized and environmentally friendly, and it is an important research direction in rail transit pit support engineering in China. The key for the construction of prefabricated diaphragm wall is the jacking process control of the sheet pile with large section. During the design stage, it is particularly important to consider how to evaluate jacking resistance and perform slurry control. In order to evaluate the jacking resistance of prefabricated diaphragm wall, a series of model pile experiments is conducted. From which, lateral resistance and tip resistance of different preformed slurry situations are studied. With the experimental results, preformed slurry control standard is proposed for prefabricated diaphragm wall deadweight and preloading jacking. According to the final results of the model pile jacking experiments, a jacking resistance evaluation model for prefabricated diaphragm wall is established, the reliable control standard for preformed slurry situation is determined, and the related software is developed. Our results show that for prefabricated diaphragm wall deadweight jacking with 1.2 m width, the slurry density could not exceed 1.15 g/cm3, and for preloading jacking with 30 ton additional pressure, the slurry density could not exceed 1.33 g/cm3.

Key words: fabricated, diaphragm wall, jacking resistance, precast pile, model experiment, slurry buoyancy