海上旋喷桩施工移动作业平台研究应用

Research and application of mobile working platform for construction of offshore jet grouting piles

为解决浅滩海域、低净空以及既有桥梁结构对旋喷桩施工的影响,结合深中通道东人工岛工程,对海上移动作业平台+接杆旋喷桩施工技术展开研究并投入生产应用。工程实践表明:1)移动作业平台+接杆旋喷桩施工技术有效地解决了海上旋喷桩施工存在的技术难题,作业平台的适用性广泛;2)基于理论计算公式的提速动态调控手段可较好地保证旋喷桩施工质量,水泥用量的偏差率仅为2.4%;3)施工过程对既有桥梁结构的影响主要表现为顺桥向的水平位移,变形值在-1.3~1.7 mm范围波动,满足极敏感建(构)筑物的高控变要求。

In order to overcome the influence of shallow seas,low headroom and existing bridge structure on the construction of jet grouting piles,the construction technology of mobile working platform+jet grouting with connecting rods at sea was studied and put into practical application,based on the contraction practice of the East Artificial Island of Shenzhen-Zhongshan Link.Engineering practice shows that:1)the construction technology of mobile working platform+jet grouting with connecting rods effectively solves the technical problems in jet grouting pile construction at sea and the working platform has a wider applicable range;2)the dynamic speed control system based on theoretical calculation formulae can better ensure the quality of jet grouting pile construction,and the deviation rate of cement dosage is only 2.4%;3)the impact of the construction process on the existing bridge structure is mainly manifested in horizontal displacement in the down-bridge direction and the deformation value fluctuates in the range of-1.3~1.7 mm,which meets the high requirements for deformation control of extremely sensitive buildings(structures).