火灾下预应力波纹腹板组合梁有效宽度研究

Analysis of Influence Parameters of Effective Width of Prestressed Composite Beams with Corrugated Webs Under Fire

采用有限元方法对高温下预应力波纹腹板组合梁有效翼缘宽度进行了分析,以典型跨度组合梁为例重点研究了火灾高温、宽跨比、荷载类型和拉索构形等参数对组合梁有效翼缘宽度的影响。结果表明,均布荷载作用下组合梁跨中截面有效翼缘宽度随温度升高呈现先减小后增大的趋势,随着宽跨比增大而减小;单点加载作用和两点作用下组合梁有效翼缘宽度随温度升高呈现先增大后减小的趋势,集中力作用处有效翼缘宽度较小;折线布索组合梁有效翼缘宽度偏小。最后提出了高温下组合梁有效翼缘宽度简化计算公式,可为工程设计提供参考。

In order to study the change of effective flange width of prestressed composite beams with corrugated webs.FEA was used to analyze effective flange width of prestressed composite beams with corrugated webs,and the influence of the high temperature,wide span ratio,load type and cable configuration on composite beams was studied by taking composite beams with typical span as examples.The results show that the effective flange width of composite beams decreases firstly and then increases with the increase of temperature under uniform load and decreases with the increase of the width span ratio.The effective flange width of composite beams under single-point loading and two-point loading firstly increases and then decreases with the increase of temperature,and the effective flange width of composite beams under concentrated loading is small.The effective flange width of composite beams with broken wires is small.At last,a simplified formula for calculating effective flange width of composite beams at high temperature was proposed,which can provide reference for engineering design.