分期进行加水冷却混凝土的方法是高拱坝施工中非常重要的温控措施，对小湾拱坝施工中2种二期冷却方案进行了对比分析研究。结果显示：直接进行冷却的二冷方案可能会导致坝体出现较大的温降梯度，使得坝体部分高程出现较大的拉应力；而采用过渡方法的二期冷却方案一定程度上消除了坝体沿高度方向的温度梯度过大现象，并且对减小坝体拉应力有较显著的效果。实践证明，二期冷却过渡方案已取得了较好的效果。

Cooling concrete in different stages in different schemes of water pipe cooling is one of the important temperature control measures in the construction of the high arch dam, and the comparison of two ways of second stage artificial cooling in Xiaowan arch dam is presented. The study result shows that: with the scheme of direct second stage artificial cooling, the temperature gratitude may be so biggish that the tensile stress appears in certain elevation of the dam; with the way of transitional second stage artificial cooling, the temperature gratitude can be decreased effectively and the tensile stress in the dam can be eliminated somewhat. Obviously, through the comparison of two kinds of artificial cooling schemes, the later is better than the fomer. In construction practice, the transitional second stage cooling scheme has received good effect.