摘要
基于摩擦抗剪的概念,提出一种确定横向预应力张拉设计值的方法.计算表明:在考虑板间铰缝及混凝土桥面板纵向开裂的情形下,装配式板桥的横向联结性能随着横向预应力的增大而增加;但是当横向预应力水平达到一定的程度(如Np0)之后,其横向联结性能基本不变,横向预应力的设计张拉值应大于Np0.通过美国马里兰州的一座装配式实心板桥的车载试验,研究了横向预应力对桥梁横向联结性能的影响.理论及试验表明,当桥面板及铰缝没有纵向开裂时,板间具备了足够的荷载横向传递能力,横向预应力对桥梁的横向联结性能影响不大.但横向预应力的存在,保证了铰缝和铺装层开裂后桥梁具有良好的横向联结性能,可以有效地抑制纵向裂缝病害的发展,确保桥梁的使用性能和安全性.
An approach based on the concept of shear friction,which is used for designing the transverse post-tensioning in the slab bridges,is presented.Calculation shows that the transverse performance of the slab bridge is stronger as the transverse post-tensioning increases,considering the shear keys and overlays crack longitudinally.However,the transverse performance can＇t be improved if the transverse post-tensioning reaches a certain level（like Np0）.Therefore,the required post-tensioning force should be greater than Np0.In addition,a newly rehabilitated bridge in the state of Maryland is load tested for evaluating the effect of transverse post-tensioning under truck load.The results of calculation and experiment indicate that the effect of higher transverse post-tensioning on the structural integrity prior to the cracking of shear key is not obvious due to the enough load transfer capability of uncracked shear keys and overlays.However,once shear keys and overlays crack,the transverse post-tensioning rods are engaged which prevents the structure from experiencing further deterioration,making the structure behave in monolithic manner.
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2010年第6期1264-1270,共7页
Journal of Southeast University：Natural Science Edition
关键词
装配式板桥
横向预应力
铰缝
摩擦抗剪
接触单元
assembly slab bridge
transverse post-tensioning
shear key
shear friction
contact element
