多层砖混结构住宅顶层旧体易产生温度引起的裂缝，主要是由于屋面受到阳光的辐射与墙体产生的温差较大（约20C左右），在相同的温度变化情况下，钢筋混凝土线膨胀系数比粘土砖的线膨胀系数大一倍，这就使屋盖的温度变形要比粘土砖墙体变形大的多，在墙体与屋盖的接触面上产生了 Multi-layer brick-concrete structure residential old building is easy to produce temperature-induced cracks, mainly due to the large temperature difference (about 20C) between roof radiation and wall radiation. Under the same temperature change, the expansion of reinforced concrete lines The coefficient is twice as large as the coefficient of linear expansion of the clay brick, which causes the temperature deformation of the roof to be much larger than the deformation of the clay brick wall, resulting in the interface between the wall and the roof.