整体现浇斜板桥的裂缝成因

Cracks in integral skew slab bridge cast-in-site

对于整体现浇斜板桥出现底板裂缝等病害,通过结构内力、应力计算进行了分析。结果表明,对于宽的斜板桥不宜采取整体现浇,而宜于在斜板的纵向增加一、两条铰缝,从而使支承反力分布趋于均匀,横向弯矩减小,主应力值减小;不得已要采用整体现浇,则应注意横向抗弯钢筋和抗扭钢筋的配置,且预应力筋束必须满足顶、底缘应力限值及强度的要求。

In dealing with the crack disease appeared on bottom slab for many integral skew slab bridge castinsite,its structure internal force and stress were calculated.The results show that integral castinsite is not a suitable construction method for wide skew slab bridges, the suitable one is to add one or two warping joints along the longitudinal direction of diagonal slab bridge, so as to distribute the internal force more even. If the integral castinsite method have to be used, attention must be paid to the distribution of antibending and antitwisting steel in cross section, and prestressed steel tendon must meet the needs of strength,the stress on top and bottom edge must reach the limit.