钢-薄层UHPC轻型组合桥面结构抗弯疲劳及剩余承载力试验研究  

Experimental Study on Fatigue and Residual Capacity of Steel-thin UHPC Lightweight Composite Deck Structure under Flexural Loads

作　　者：曹君辉[1,2] 赵宇航 邵旭东[1,2] 沈秀将[1,2] CAO Junhui;ZHAO Yuhang;SHAO Xudong;SHEN Xiujiang(College of Civil Engineering,Hunan University,Changsha 410082,China;Key Laboratory for Wind and Bridge Engineering of Hunan Province(Hunan University),Changsha 410082,China)

机构地区：[1]湖南大学土木工程学院,湖南长沙410082 [2]风工程与桥梁工程湖南省重点实验室(湖南大学),湖南长沙410082

出　　处：《湖南大学学报（自然科学版）》2022年第11期89-104,共16页Journal of Hunan University:Natural Sciences

基　　金：国家自然科学基金资助项目(51978259,51708200);湖南省科技创新计划资助项目(2021RC3068)。

摘　　要：为探明栓钉间距对钢-UHPC轻型组合桥面结构受力性能的影响规律,完成了3个钢-UHPC组合梁试件变幅疲劳试验,主要试验变量为栓钉间距(100 mm、150 mm、300 mm).在疲劳试验中,重点考察了栓钉间距对轻型组合桥面结构疲劳性能的影响,并关注了栓钉焊趾处钢面板受拉-短栓钉受剪耦合作用下的疲劳性能;而在疲劳后的剩余承载力试验中,探明了栓钉间距对疲劳后UHPC裂缝发展规律及抗弯承载力的影响.疲劳试验结果表明,当栓钉间距为300 mm时,单位荷载下的钢-UHPC界面滑移明显高于其他两个试件,但在疲劳加载过程中,界面滑移增长并不明显;对于U肋受压区底板应变,当栓钉间距为100 mm和150 mm时,整个疲劳试验过程无明显变化,而当栓钉间距为300 mm时,应变呈现微小的增大趋势;为分析试件中栓钉根部的钢面板拉-剪耦合疲劳受力状态,基于《公路钢混组合桥梁设计与施工规范》(JTG/T D64-01—2015)中的计算方法进行了分析,结果表明,该方法能够获得偏保守的计算结果.此外,疲劳后的剩余承载力试验表明,栓钉间距越小,试件的塑性变形能力越强,截面的抗弯承载力相应提高.分别按弹塑性理论和塑性理论计算了试件的剩余承载力,发现试件虽然经历了疲劳加载,但测承载力仍大于计算承载力,且基于塑性理论的计算结果更接近实测结果.In order to reveal the influence law of the stud spacing on the behavior of steel-UHPC lightweight composite deck structures,variable amplitude fatigue tests were accomplished for three LWCD beam specimens and the stud spacing was chosen as the core parameter in the tests(i.e.,100 mm,150 mm,300 mm).In the fatigue tests,the influence of the stud spacing on the fatigue performance of the LWCD was revealed and the combined tensionshear fatigue properties of the steel deck plate at stud root positions were obtained.In the residual capacity test after the fatigue tests,the influence of stud spacing on the cracking evolution mechanism in UHPC and on the residual ca⁃pacity of the specimens was captured.The fatigue tests indicated that when the stud spacing was 300 mm,the unitload induced slips at the steel-UHPC interface were much higher than those in the other two specimens,but the slips did not increase significantly during the fatigue testing process.When the stud spacing was 100 mm or 150 mm,the strain at the bottom flange of the U rib did not exhibit significant change,and the strains increased slightly when the stud spacing was 300 mm.On the basis of the calculation method prescribed in the code of“Specifications for Design and Construction of Highway Steel-concrete Composite Bridge”in China,the combined tension-shear fatigue state of the steel deck plate at stud root positions was analyzed,and the results implied that this method could provide conservative results.In addition,the residual capacity test after the fatigue testing showed that the smaller the stud spacing,the smaller the interfacial slip and the higher the residual flexural capacity.On the basis of the elastic-to-plastic theory and plastic theory,the residual capacities of the specimens were predicted.It was revealed that although the specimens experienced a series of fatigue loading,the actual residual capacities obtained in the tests were still higher than the predicted values,and the plastic theory exhibits a better agreement relative to the

关 键 词：正交异性钢桥面板 超高性能混凝土 轻型组合桥面 栓钉间距 疲劳试验 剩余承载力 

分 类 号：U443.33[建筑科学—桥梁与隧道工程]