Research purposes:In order to investigate the mechanical performance of UHPC layer in the negative moment zone of small span continuous frame bridges,the crack resistance ability,rotation ability and ultimate bearing capacity of the joint were investigated by using the real bridge scaling model.Based on ABAQUS finite element software,the numerical simulation and parameter analysis of the test model were carried out to explore the effects of key parameters such as UHPC layer length,thickness and reinforcement ratio on mechanical performance of the negative moment joints of the frame bridges.Research conclusions:(1)The UHPC layer of frame bridge joint has a high cracking stress(6.56 MPa).In the normal use stage,the UHPC layer effectively inhibits the formation and development of cracks in the negative bending moment zone,and improves the overall cracking resistance of the structure.(2)Increasing the reinforcement ratio of UHPC layer can effectively improve the flexural bearing capacity of frame bridge joints,but will reduce the cracking resistance of UHPC surface layer.(3)The crack resistance and load bearing capacity of frame bridge joint increases with the increase of UHPC layer thickness.(4)On the premise that both the UHPC layer and the UHPC-NC interface have good crack resistance,it is the most economical to set the UHPC layer between the zero points of the negative bending moment of frame bridge.(5)The research results put forward a high performance joint design method for the negative moment zone of small span continuous frame bridge,which can provide an effective reference for similar bridge design.
关键词
连续框架桥/负弯矩区/超高性能混凝土(UHPC)/试验研究/有限元分析
Key words
continuous frame bridge/negative bending moment/ultra-high performance concrete(UHPC)/experimental study/finite element analysis
维普
万方数据