预应力混凝土Ⅰ型梁温度梯度分布规律

The distribution law of temperature gradient of prestressed concrete type Ⅰ beams

为解决现有公路桥梁设计规范中缺少的横向温度梯度效应的相关问题,本文对自然条件下3种不同结构尺寸的Ⅰ型梁截面实测与预测温度梯度进行了比较,通过分析得出Ⅰ型梁体截面底部Ⅴ型区段凸缘部位为最大横向温度梯度的发生位置。研究表明,梁体横向不同区段部位混凝土受太阳辐射的不均匀加热会导致显著的非线性温度梯度,进而修正设计规范中主梁的垂直温度梯度,对设计规范中横截面温度梯度效应的相关内容做了有益补充,为今后混凝土桥梁温度梯度荷载的研究提供了可靠性依据。

In order to solve the problem of transverse temperature gradient effect lacking in the existing specifications, a comparative analysis of the measured and predicted temperature gradient in the section of type Ⅰ-beam with three different structures under natural conditions was carried out, and it was concluded that the flange of the Ⅴ-section at the bottom of the section of type Ⅰ-beam was the location where the maximum transverse temperature gradient occurred.Research shows that the beam body transverse section different place concrete uneven heating by solar radiation can lead to significant nonlinear temperature gradient, the vertical temperature gradient and design code of fixed girder, the design of the cross section temperature gradient effect in the specification and the related content made a beneficial supplement for the concrete bridge temperature gradient load research provides a reliable basis. In order to solve the problem of transverse temperature gradient effect lacking in the existing specifications, a comparative analysis of the measured and predicted temperature gradient in the section of type Ⅰ-beam with three different structures under natural conditions was carried out, and it was concluded that the flange of the Ⅴ-section at the bottom of the section of type Ⅰ-beam was the location where the maximum transverse temperature gradient occurred.