摘要
目的对某自锚式悬索桥进行对比研究,确定合理的有限元分析模型,为桥梁现场试验提供指导.方法对该自锚式悬索桥的钢箱加劲梁分别采用板单元、既考虑弯曲又考虑剪切变形的梁格单元以及只考虑弯曲变形的梁格单元建立3种有限元模型,在结构自重情况下将有限元模型的计算结果与实测结果进行对比,给出合理的有限元分析模型.结果在自重及静载试验情况下,板单元模型计算给出的顺桥向各吊杆应力值较均匀;两种梁模型给出的顺桥向各吊杆应力值相差较大,尤其是桥梁两端吊杆的应力明显小于其他吊杆的应力.静载试验中,吊杆中的最大应力值是873 MPa,符合规范要求;桥面与各吊杆连接点处的沉降值都是板单元模型最小,两种梁模型的较大,最大沉降量都为2.7～3.0 cm.结论采用板单元模型模拟钢箱加劲梁比采用梁单元模拟更合理.静载试验下,吊杆最大应力满足规范要求,结构安全.静载试验预测给出的桥面与各吊杆连接点处的沉降量可用于自锚式悬索桥的现场试验.
Three finite element（FE） models are compared for a self-anchored suspension bridge in order to obtain the appropriate analysis model.The numerical predictions under the static load test are carried out.The shell element and two types of beam elements based on grillage method are used to simulate the steel box stiffening girder of the bridge.One of the grillage methods considers not only the bending deflection but also the shear deflection.The other one considers the bending deflection,but neglects the shear deflection.Four measurement data of the equivalent stress on the bottom plate of the steel box are used to test the three finite element models under the dead load of the self-anchored suspension bridge itself.The equivalent stresses are obtained by using the shell element model at the four measurement points,which are closed to the actual measurement data.The two beam models are not ideal.It demonstrated that the shell element model was the appropriate finite element model for simulating steel box stiffening girder of the self-anchored suspension bridge.The suspender stresses and the suspender subsidence at the junction with bridge deck were predicted for the cases of static load test.The suspender stresses calculated by the shell element model were even for all the suspenders.The stresses of the longest suspender and the shortest suspender were much less than the other suspender stresses when the two beam models were used.The maximum suspender stress is 873 MPa.The result of test meet the requirement of the standards.The predicted subsidence data of junction of the suspenders and bridge deck for the static load test were between 2.7 cm and 3.0 cm which could be used as the reference data in the practical static load test.
出处
《沈阳建筑大学学报（自然科学版）》
CAS
北大核心
2010年第6期1033-1038,共6页
Journal of Shenyang Jianzhu University：Natural Science
基金
国家自然科学基金项目(10972144)
关键词
自锚式悬索桥
钢箱加劲梁
板单元
梁单元
静载试验
self-anchored suspension bridge
steel box stiffening girder
shell element
beam element
static load test
