软土地基堆载对桥梁桩基影响及保护分析  

Analysis of the Impact of Surcharge on the Bridge Pile and the Protection in Soft Soil Area

作　　者：李志伟[1,2] 杨建学[1,2] 俞伟[1,2] 陈致富 

机构地区：[1]福建省建筑科学研究院,福州350025 [2]福建省绿色建筑技术重点实验室,福州350025

出　　处：《工程建设与设计》2016年第7期81-85,共5页Construction & Design for Engineering

基　　金：福建省科技计划项目(2014Y0016);福建省建设科技研究开发项目(2012K15)

摘　　要：在软土地区,桥梁桩基周边的不对称堆载将引发桩基产生偏位,并产生附加弯矩,严重时将影响桥梁的安全使用。结合具体工程实例,分析了不对称堆载及后期行车荷载对桥梁桩基的内力与变形的影响,对桩基竖向承载力、抗弯承载力及裂缝进行验算,并对堆土反压措施的保护效果进行分析。通过分析结果可知,在路堤填土和道路荷载的作用下,位于堆载边缘的墩柱及基桩均将发生一定程度的偏位,并将在桩身产生较大的附加弯矩;而位于堆载中心区域因堆载较为均衡,堆载对墩柱及基桩的偏位、桩身附加弯矩的影响则很小。当桥梁墩柱周边采用堆土反压时,反压土对于控制墩柱及桩基的偏位具有较好的作用,对控制基桩附加弯矩及裂缝宽度均具有明显效果。In soft soil area, the lateral displacement and the additional bending moment of the bridge pile will be caused by the asymmetric load, which will affect the safety of the bridge. Combined with specific engineering, the impact of the asymmetric load and vehicle load on the bridge pile is analyzed. The vertical bearing capacity, bending capacity and maximum crack width of the pile is reviewed, and the protection effect of the earth berm is analyzed. The analysis result shows that, the lateral displacement of the bridge pile will be caused under the action of the asymmetric load and vehicle load, and additional bending moment will be produced at the same time. The lateral displacement and the additional bending moment can be ignored, when the surrounding load is relatively balanced. The earth berm has good effect on controlling the deflection of the bridge pile, which is used to ensure the balance of the pile foundation. In addition, it has obvious effect on the control of additional bending moment and crack width of pile.

关 键 词：不对称堆载 桥梁桩基 保护 软土地基 

分 类 号：U443.15[建筑科学—桥梁与隧道工程]