摘要
黄韩侯铁路纵目沟特大桥5号主墩高105 m,采用柱板式空心墩,为探索新型高墩最佳受力状态,保证施工和运营安全性,采用Midas/Civil软件对下横梁以下墩身混凝土收缩特性进行计算分析,根据工程设计经验结合现场实际状况对主桥墩高设置、基础设计进行优化,采用缩尺模型试验对高墩破坏形态进行模拟。研究结果表明:高墩墩底实体段和空心段交界处,混凝土收缩引起的局部拉应力最大可达7.3 MPa,通过全截面配置普通钢筋解决;受地形条件控制,适当提高承台、降低墩高在山区铁路设计中效果明显,桩基础采用大直径、不等桩长布置形式更合理;缩尺模型试验构件原型选取连接板纵横向宽度对比明显的墩身较理想,采用半圆形楔形块将地锚螺栓杆与地面连接牢固等措施保证实验数据准确。新型桥墩结构的成功建设,体现出细节设计是保证整体结构安全性、耐久性、可实施性和合理性的关键和基础。
The No.5 main-pier of the Zongmugou grand bridge on the Huangling-Hancheng-Houma railway is a 105 meters high column-slab hollow pier.In order to explore the optimum stress state of the high pier and ensure the safety during construction and operation,the Midas/Civil software is used to compute and analyze the concrete shrinkage characteristics of the pier below the lower transom.The height of the main-pier and foundation design are optimized according to the design experiences and local situations,and the failure mode of high pier is simulated by means of scale model test.The research result shows that in the junction area of solid-hollow part of the high pier bottom,the maximum local tensile stress is 7.3 MPa due to concrete shrinkage,which could be counteracted by total cross-section arrangement of reinforcement.Proper measures are taken such as raising the height of pile cap while reducing the height of pier.Large diameter piles with unequal length are employed.In comparison with the width of the junction plate in the pier scale-model,the adoption of semicircle wedge blocks to tie the anchor bolt firmly to the ground insures correct test data.The successful construction of the new type pier structure indicates that good detail design guarantees safety,durability,implementation and rationalization of the entire structure.
作者
李兆章
LI Zhaozhang(China Railway First Survey and Design Institute Group Co.,Ltd.,Xi'an 710043,China)
出处
《铁道标准设计》
北大核心
2021年第3期106-111,共6页
Railway Standard Design
基金
中国铁建股份有限公司科技研究开发计划课题(2011-55C)。
关键词
铁路桥梁
柱板式空心墩
收缩分析
墩高设计
基础设计
试验模型设计
railway bridge
column-slab hollow pier
shrinkage analysis
pier height design
foundation design
test model design
