摘要
为研究波纹钢腹板体外预应力混凝土箱梁的塑性铰长度问题,采用有限元数值计算与既有试验数据相结合的方法,确定这类箱梁在地震等破坏荷载下的内力重分布及塑性变形能力。基于OpenSees平台建立了波纹钢腹板体外预应力混凝土箱梁的非线性有限元数值计算模型,利用2个不同学者的试验数据,从破坏荷载、跨中挠度、体外预应力筋应力增量、混凝土压应变等方面验证了数值计算模型,并对比分析了计入剪切变形和不计入剪切变形对箱梁挠度的影响;在此基础上,对影响波纹钢腹板体外预应力混凝土箱梁塑性铰长度的参数进行了研究。最后,通过比较已有公式的塑性铰长度计算值与数值模拟值,提出了适合波纹钢腹板体外预应力混凝土箱梁的塑性铰长度计算式。结果表明:实际计算中可以不计入剪切变形对波纹钢腹板体外预应力混凝土箱梁挠度的影响;剪跨比和有效预应力对波纹钢腹板体外预应力混凝土箱梁的塑性铰长度有显著影响,而受拉钢筋面积和混凝土强度对该类箱梁塑性铰长度的影响相对较小。
In order to investigate the plastic hinge length of externally prestressed concrete box girders with corrugated steel webs, the finite element numerical calculation combined with the existing test data was adopted to determine the internal force redistribution and plastic deformation ability of the girders under failure load such as earthquake. The nonlinear finite element numerical model of externally prestressed concrete box girders with corrugated steel webs was established based on OpenSees platform and verified from the aspects of failure loads, mid- span deflections, stress increments in external tendons and concrete compressive strains by experimental data from two researchers. In addition, the effects of numerical models with or without considering shear deformation on the box girder deflection were comparatively analyzed.Parametric analysis was carried out to investigate factors that may affect the plastic hinge length of externally prestressed concrete box girders with corrugated steel webs. Finally, through comparing the calculation results of existing equations and simulated results, an equation for estimating the plastic hinge length was recommended for externally prestressed concrete box girders with corrugated steel webs. The results show that the effect of shear deformation on deflection of externally prestressed concrete box girders with corrugated steel webs can be neglected in practical computation. The shear span ratio and the effective prestress have significant impact on the plastic hinge length of externally prestressed concrete box girders with corrugated steel webs, while the reinforcement steel area of tensile zone and the concrete compressive strength have relatively limited effect on the plastic hinge length.
出处
《中国公路学报》
EI
CAS
CSCD
北大核心
2017年第5期67-73,共7页
China Journal of Highway and Transport
基金
国家自然科学基金项目(51278521)
陕西省交通运输厅科技项目(14-16K)
关键词
桥梁工程
塑性铰长度
有限元法
混凝土箱梁
波纹钢腹板
体外预应力
bridge engineering
plastic hinge length
finite element method
concrete box girder
corrugated steel web
external prestress
