The pile raft structure of prestressed pipe-pile and reinforced concrete slab was applied in reinforcing the deep silt foundation of the high-speed railway transition section between bridge abutment and embankment. The field tests were performed, including lateral displacement and pore water pressure of the abutment foundation, settlement of the pile-raft structure and bending moment and lateral displacement of the abutment pile. Based on the measured data, the effects of driving pipe-piles on the abutment foundation, constructing embankment near the transition section on the pile-raft structure stability and subgrade fill on the abutment pile were studied. The results show that: driving pipe-piles squeezes the adjacent abutment foundation, and the abutment impact-cone concrete piles should be constructed after 5 months following finishing the pipe-piles; constructing embankment near the transition section causes the pile-raft structure to float or uneven subside; the subgrade fill compresses the silt, which makes the abutment pile deviate.%针对采用"预应力管桩+钢筋混凝土板"的桩筏结构加固处理高速铁路路桥过渡段的深厚淤泥地基,选择两处过渡段开展现场试验,基于实测结果分析桥台地基土的侧向位移和孔隙水压力、桩筏结构的沉降、桥台基桩的弯矩和侧向位移的变化特点及其产生原因,研究过渡段打入管桩对邻近桥台地基的影响、靠近过渡段的路基填土对桩筏结构稳定性的影响、台后路基填土对桥台基桩的侧向影响.结果表明:过渡段打入管桩会挤压邻近的桥台地基,若不采取其他措施,宜等管桩全部打完5个月后再开始钻进靠近管桩的桥台冲孔灌注桩孔;靠近过渡段的路基填土使桩筏结构先上浮然后不均匀下沉;采用桩筏结构对过渡段的淤泥地基进行加固处理后,台后路基填土仍会使下卧淤泥侧向移动而挤压桥台基桩,使桥台基桩偏移.
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