刚果共和国布拉柴维尔商务中心桩基设计

摘要

刚果共和国布拉柴维尔商务中心基础处于平面上软土与硬岩交叉分布、竖向胶结岩体与碎散细粒土交替互层的复杂地基上,其荷载集度高且离散性较大.依据承载力等效原则,采用灌注桩后注浆工艺提高基桩承载力并依土层分布调整注浆参数均匀化地基;依据变刚度调平原理,通过核心筒与边柱基础分区荷载平衡减少基础弯矩和非均匀沉降.现场试验表明,基桩承载力及沉降均满足规范要求.该项目桩基优化设计减少了复杂地层的成桩长度而降低了施工难度,节省了工程量,改善了基础受力条件,获得了良好的技术经济效益.%The Republic of the Congo Brazzaville Commercial Center is located on the non-uniform sub ground,in which soft soil and hard rock are crossing distribution in the flat surface and cement rock mass and fine grained soil are alternating layers in the vertical division,and the structural pressure is high degrees and discreteness.According to the equivalent rule,the post grouting technique is used to improve the bearing capacity of the pile,and the grouting parameters are adjusted to homogenize in the various stratum of the sub ground.According to the balanced method,the load acted on core tube area and the side column are balanced separately to reduce the bending moment and differential settlement.The site tests show that the settlement and bearing capacity of pile can satisfy the requirements of specification.A series of technical and economic benefits are obtained by the pile foundation optimization design such as the pile-forming length in complex stratum shorten,so the construction difficulties reduce,and the bearing capacity of foundation improves.