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施工温降是引起碾压混凝土拱坝裂缝的主要荷载。均匀温降作用下拱坝在裂缝前整个断面处于受拉状态，最大拉应力出现在拱端上游面和拱冠下游面。均匀温降使碾压混凝土拱坝全断面受拉，坝体形成深层的或贯穿性的裂缝对拱坝的危害较大。施工温降在水库放空时所产生的裂缝深度一般比水库蓄满时大。水荷载所产生的压应力可以部分或全部抵销温降所产生的拉应力。一般来说，上游水荷载对拱坝的作用更大，它在拱圈大部分区域产生很大的压力，因而使裂缝的扩展受到抑制。用水平拱作为计算图形进行结构分析，能较好地反映出碾压混凝土拱坝的应力和裂缝状况；混凝土的钝裂缝带模型用于有限元断裂分析和确定裂缝扩展深度比较方便。
Construction temperature drop is the main load that causes cracks in RCC arch dam. Under the uniform temperature drop, the entire section of the arch dam is under tension before the fracture, and the maximum tensile stress appears on the upstream face of the arch and the downstream face of the arch crown. The uniform temperature drop makes the whole section of RCC arch dam under tension, and the deep or penetrating cracks formed on the dam body are more harmful to the arch dam. Construction temperature drop when the reservoir venting cracks generated when the reservoir is generally larger than the reservoir. The compressive stress generated by water load can partly or totally offset the tensile stress caused by temperature drop. In general, the upstream water load has a greater effect on the arch dam, and it generates a lot of pressure in most of the arch ring, thereby suppressing the expansion of the crack. The structural analysis of the horizontal arch as the calculation graph can well reflect the stress and crack status of the RCC arch dam. The blunt cracked belt model of concrete is more convenient for the finite element analysis and determination of the crack propagation depth.