预制工形梁变形影响因素分析与控制

Analysis and Control of Deformation Influencing Factors of Precast I-shaped Beam

为了明确施工阶段影响预制工形梁梁体变形的主要因素,针对弹性模量、孔道偏位、日照温度影响因素进行相关理论分析,并结合实际情况,通过Midas/Civil建立39.6 m单梁实体有限元分析模型,进行影响因素作用下梁体侧弯及挠曲变形分析。结果表明:满足规范张拉强度的混凝土其弹性模量指标对梁体侧弯变形影响较小;平弯钢束的张拉是造成梁体侧弯的直接原因,后张拉钢束对梁体侧弯有修正作用;日照温度会增加工况作用下梁体挠曲变形,增幅达26%;结果可为预制梁变形原因分析及过程防控提供参考。

In order to clarify the main factors influencing the deformation of the prefabricated beams during the construction phase,relevant theoretical analysis is conducted on the factors about the elastic modulus,channel deviation,and sunshine temperature.The 39.6m single beam solid finite element analysis model is used to analyze the lateral bending and deflection deformation of the beam body under the influence of the influencing factors.The results show that the elastic modulus index of the concrete that meets the standard tensile strength has little effect on the lateral bending deformation of the beam body.The analysis shows that the tension of the flat-bent steel beam is direct cause of the lateral bending of the beam,and the post-tensioned steel beam has a correction effect on the lateral bending of the beam.The influence of sunshine temperature will increase deflection and deformation of the beam under the working conditions,with an increase of 26%.It can provide reference for analysis of deformation of the precast beam and the process prevention and control.