为解决大体积混凝土坝温控防裂研究脱离实际施工信息的问题,以某中型混凝土重力坝泄洪排沙底孔坝段为对象,建立三维热力耦合有限元模型,纳入廊道封堵、越冬保温、表面保温、水管冷却四种施工信息,精准模拟浇筑全过程.通过分析施工信息对坝体温度场、应力场的影响,识别高开裂风险部位,基于拉应力平衡法提出量化配筋方案.结果表明:“内降外保”温控措施协同作用可使坝体平均最高温度降低16.1 ℃、平均最大拉应力降低33.6%;齿墙、廊道附近及坝体无水管冷却内部为高风险区,廊道附近应力集中系数达1.5,天然条件下拉应力超3.5 MPa.

To address the problem that research on temperature control and crack prevention of mass concrete dams is divorced from actual construction information, this study takes the flood discharge and sediment flushing bottom outlet dam section of a medium-sized concrete gravity dam as the research object. A three-dimensional thermo-mechanical coupling finite element model is established, incorporating four types of construction information (corridor plugging, overwintering insulation, surface insulation, and water pipe cooling) to accurately simulate the entire pouring process. By analyzing the influence of construction information on the temperature and stress fields of the dam, high crack risk areas are identified, and a quantitative reinforcement scheme is proposed based on the tensile stress balance method. The results show that the synergistic effect of the “internal cooling + external insulation” temperature control measures can reduce the average maximum temperature of the dam by 16.1 ℃ and the average maximum tensile stress by 33.6%. High crack risk areas are concentrated in the keyway, near the corridor, and the internal area of the dam without water pipe cooling; the stress concentration factor near the corridor reaches 1.5, and the tensile stress exceeds 3.5 MPa under natural conditions.