There is an increasing concern on the vulnerability of concrete gravity dams under blast loads. To a better evaluation of the blast-resistance, the effect of the initial stress field is taken into consideration herein. Firstly, a fluid-solid coupling numerical model is established to investigate the blast-resistance of concrete gravity dams. The numerical results indicate that the initial stress field has non-neglectable effect on the shock wave propagation, blast vibration, and failure mode of concrete gravity dams. The damage of dam base may be overestimated without the consideration of initial stress field. Moreover, a parametric study are carried out for further investigations of the dynamic responses and damage properties under various explosion scenarios (explosive charge, detonation depth, and standoff distance). With the consideration of the initial stress field, it can be concluded that the dam head nearest the explosive source is the weakest part, and the safety of the dam base is another important consideration, which may lead to severe dam-break floods. At last, a new method is proposed and recommended to evaluate the blast resistance of the whole concrete gravity dam, where the blast-induced vibration and penetration depth of cracks are suggested for the dam crest and dam base, respectively.

人们越来越担心爆炸荷载下混凝土重力坝的脆弱性。为了更好地评估抗爆炸性，本文考虑了初始应力场的影响。首先，建立了流固耦合数值模型，研究了混凝土重力坝的抗爆性能。数值结果表明，初始应力场对混凝土重力坝的冲击波传播，爆炸振动和破坏模式具有不可忽略的影响。在不考虑初始应力场的情况下，可能会高估坝基的破坏。此外，还进行了参数研究，以进一步研究各种爆炸场景（爆炸装药，爆炸深度和隔离距离）下的动力响应和损伤特性。考虑初始应力场，可以得出结论，离爆炸源最近的坝头是最薄弱的部分，坝基的安全性是另一个重要考虑因素，可能导致严重的溃坝洪水。最后，提出了一种新的方法来评价整个混凝土重力坝的抗爆性能，并分别针对坝顶和坝基提出了爆破引起的振动和裂缝的渗透深度。