桥梁高桩承台基础抗震性能研究  

Study of earthquake-resistant performance of high pile cap foundation of bridge

作　　者：韩振峰[1] 叶爱君[2] 

机构地区：[1]合肥学院建筑工程系,安徽合肥230601 [2]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《合肥工业大学学报（自然科学版）》2016年第2期199-204,216,共7页Journal of Hefei University of Technology：Natural Science

基　　金：国家自然科学基金资助项目(50878147);安徽省高校自然科学研究重点资助项目(KJ2015A249);合肥学院人才科研基金资助项目(15RC01)

摘　　要：文章通过3个钢筋混凝土群桩试件在低周反复荷载作用下的受力性能试验研究,讨论了群桩基础破坏形态及滞回特征,解释了其破坏机理,分析了土体参数、密实度及桩身自由段长度等对其延性的影响。结果表明,极限状态时,群桩结构受力模式会由地基梁模型转变为悬臂柱模型;减小自由长度和提高土体含水率都会增加其抗震性能。在OpenSees有限元框架中建立了群桩基础有限元模型,使用弹塑性纤维梁柱单元模拟桩体,采用非线性p-y单元模拟桩土相互作用;对模型进行了单调Pushover分析,并且对分析结果与试验结果进行了比较,结果表明该模型能很好地模拟试验数据。Firstly, based on an experimental research on three reinforced concrete pile foundation specimens tested under low cyclic loads, the destroy pattern and hysteretic characteristic of pile group foundation were discussed, the destroy mechanism was explained, and the effect of soil parameters, compactness, and free length of the pile on the foundation ductility was analyzed. The results show that the mechanical pattern of the foundation may change from the foundation beam model to the cantilever column model at the ultimate state, and reducing free length of the pile and raising the moisture content of the soil can improve the earth- quake-resistant performance of the foundation. Secondly, a finite element model of this foundation was built in the OpenSees framework. In the model, the fiber element was used to simulate the pile shaft, and the non-linear p-y element was used to simulate the soil-pile interaction. Thirdly, the monotonic Pushover analysis was performed on the model, and the results were compared with the test results. The results show good co- herence with the experimental data.

关 键 词：桥梁工程 高桩承台 群桩基础 抗震性能 拟静力试验 

分 类 号：U442.55[建筑科学—桥梁与隧道工程]