摘要
混凝土桥梁在自然环境中受温度荷载作用。我国、德国及国际铁路联盟无缝线路相关规范中均规定梁体温度荷载采用均匀温度荷载,但我国铁路桥涵及国内外公路桥涵规范中,对于混凝土梁体温度荷载的取值,均采用不均衡温度荷载(即温度梯度荷载),与均匀温度荷载存在差异。计算分析桥梁不同均匀温度荷载及温度梯度荷载对桥上无缝线路伸缩附加力的影响,有益于进一步深入研究桥上无缝线路受力机理。同施加均匀温度荷载相比,施加温度梯度荷载时,桥上无缝线路伸缩附加力较小。温度梯度荷载较为符合桥梁实际温度荷载条件,《暂规》中梁体温度荷载取值相对保守。鉴于伸缩附加力在桥上无缝线路检算中的重要作用,建议进一步深入研究,对梁体温度荷载的取值进行大量的试验研究。
Concrete bridges in the natural environment are affected by temperature loads. Temperature load on bridge in codes about CWR of China, Germany and UIC is uniform temperature load. But in the code of China Concrete Structure of Railway Bridge and Culvert code and highway bridges and culverts codes at home and abroad, the temperature load of concrete bridges is imbalanced （temperature gradient load） and is more tallied with the actual situation. It is different with the former. Based on the finite element theory, build the model of box girder with double-block bitllastless track. Calculate the influences of different temperature loads and temperature gradient loads on bridge on the additional expansion and contraction forces of CWR on bridge. The results show that with the increase of the temperature load, the additional expansion and contraction forces increase continuously. When apply temperature gradient load, the additional expansion and contraction forces of CWR on bridge is smaller than that when applying uniform temperature load. The temperature load on bridge in temporary provisions is relatively conservative. Propose a further study on the temperature load on bridge and carry out massive experimental researches on the value of temperature load on bridge.
出处
《铁道标准设计》
北大核心
2011年第10期1-3,7,共4页
Railway Standard Design
基金
铁道部科技研究开发计划项目(2010G001-D)
中央高校基本科研业务费专项资金资助课题(2009JBZ014)
关键词
均匀温度荷载
温度梯度
无缝线路
伸缩附加力
uniform temperature load
temperature gradient load
CWR
the additional expansion and contraction forces
