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为了研究混凝土浇筑早期水化反应引起的温度变化对钢混组合梁桥变形和应力的影响,以一简支梁桥为试验对象,测试了混凝土桥面板和钢梁在混凝土浇筑前后温度和应变变化数据,并对钢梁由于温度变化引起的应力进行了解析。分析结果表明:混凝土在凝结硬化过程中温度先升后降,在升温阶段结束后,混凝土板获得足够的刚度来约束钢梁的变形,在降温阶段结束后混凝土桥面板与钢梁变形协调。混凝土板在降温阶段的收缩受到了钢梁顶板的约束,拉应力开始产生。降温阶段结束后混凝土板中拉应力的大小与升温阶段结束后钢梁横截面上的温度梯度以及混凝土板与钢梁顶板的温差有关。
In order to study the influence of temperature change caused by early hydration reaction on the deformation and stress of concrete composite beam bridge, a simply supported beam bridge was used as test object to test the changes of temperature and strain before and after pouring of concrete bridge deck and steel beam Data, and analyze the stress caused by the temperature change of the steel beam. The results show that the temperature of concrete increases first and then decreases during the setting and hardening process. After the temperature rising stage, the concrete slab obtains sufficient rigidity to restrain the deformation of the steel beam. After the cooling stage, the deformation of the concrete bridge deck and the steel beam is coordinated. The shrinkage of concrete slab during the cooling phase is restrained by the steel beam roof and tensile stress begins to develop. The magnitude of tensile stress in the concrete slab at the end of the cooling phase is related to the temperature gradient in the cross-section of the steel girder at the end of the heating phase and the temperature difference between the concrete slab and the steel roof.