Cause Analysis On High Uplift Pressure And Safety Assessment Of Huaguangtan Arch Dam

As the consequence of the construction of high arch dams in China, it's a significant challenge for designers and engineers to assure the safety of these high dams. Currently there are several arch dams with a relatively high uplift pressure, which still hasn't cause enough attention of engineers so far. A method of high uplift pressure of arch dam is presented for the dam safety assessment and applied to Huaguangtan arch dam. The main contents are summarized as follows:1) The advantage and shortage of the current detection technique both at home and abroad are introduced. Based on the structural feature and working condition of hydraulic structure, detection technique for the inner crack in the basement rock of arch dam is proposed.2) The inner factors of the relatively high uplift pressure are analyzed, namely, the geological conditions, foundation treatment, geometry of the dam, and concrete construction. All the factors are potential physical causes for the leak path of the dam foundation.3) The effects of load parameters variation to dam stress are analyzed. The inverse method of mechanical parameter of dam concrete is improved. Structural analysis method to analyze the structural cause of the crack in shallow bedrock of dam is investigated.4) Taking Huaguangtan arch dam as an example, based on analyses method mentioned above, the cause of relatively high uplift pressure and its effect to dam safety are analyzed. A method of structural safety analysis considering the effect of high uplift pressure in arch dam is proposed, which can be summarized as detection of the leak path, causation analyses of the leak path using construction review and structural calculation, and observed behavior of arch dam.