半预制UHPC外壳叠合盖梁试设计研究

Trial-design of Semi-prefabricated UHPC Shell Composite Cap Beam

以某天桥为工程背景,对提出的半预制UHPC外壳叠合盖梁(简称URC盖梁)进行试设计。应用有限元软件ABAQUS建立有限元模型,进行吊装阶段、施工阶段和运营阶段的受力分析,结果表明:吊装阶段中,UHPC外壳的最大拉应力和挠度较小,满足规范要求;后浇混凝土阶段中,UHPC外壳在承载能力极限状态下的最大拉应力和正常使用极限状态下的挠度在规范限值内;运营阶段中,承载能力极限状态下的UHPC外壳和核心混凝土最大压应变小于混凝土的峰值压应变,箍筋和纵筋的最大应力小于钢筋的屈服强度,URC盖梁和RC盖梁正常使用状态下的挠度较为接近,且满足规范要求。

According to the experimental condition of an overline bridge,a trial design of the prefabricated cap beam,the semi-prefabricated UHPC shell composite cap beam(short for URC cap beam)was produced.Finite element software ABAQUS is adopted to calculate and analyze the stress analysis in the hosting stage,construction stage and operation stage.The results show that the maximum tensile stress and deflection of the UHPC shell are within the limits of the code limit value in the hoisting stage.The maximum tensile stress of the UHPC shell under the ultimate limit state and the deflection under the serviceability limit state are within the limits of the code in the post-cast concrete stage.And in the operation stage,the maximum compressive strain of UHPC shell and core concrete under the ultimate limit state are less than the peak compressive strain of concrete,and the maximum stress of stirrup and longitudinal bar is less than the yield strength of steel reinforcement.The deflection of URC cap beam and RC cap beam under the serviceability limit state are close to each other and both meet the code limit value.