Large-scale shaking model tests on anti-seismic and reinforcing measures for slope of Zipingpu earth-rock fill dam after “5.12” Wenchuan Earthquake

The dry masonry facing of the downstream slope of Zipingpu earth-rock fill dam was seriously destroyed during “5.12” Wenchuan Earthquake. Accordingly, the anti-seismic reinforcement for the damaged dam slope is an important task after the earthquake. The mortar masonry facing is regarded as the best choices comprehensively considering the applicability of anti-seismic and reinforcing measures for slopes of high earth-rock fill dams after earthquake proposed by worldwide engineers and its excellent anti-seismic performance in real strong earthquakes. Large-scale shaking table model tests on anti-seismic and reinforcing measures for earth-rock fill dam slope (dry masonry and mortar masonry facings) of Zipingpu earth-rock fill dam after “5.12” Wenchuan Earthquake are performed. The anti-seismic and reinforcing effect of the masonry facings is verified by the shaking model tests, and their anti-seismic and reinforcing mechanism is analyzed. Furthermore, the reinforcement area of the dam slope using the mortar masonry facing is determined based on the test results combining with the calculated results of the dam's earthquake response. The results show that the mortar masonry facing can keep its integrity wonderfully in strong earthquake, but the dry masonry facing may fail gradually because of the loosening and sliding of local stones in strong earthquakes. The protective effects of the mortar masonry facing on the dynamic stability of rock-fill dam slope in earthquake is better than the dry masonry facing obviously. The reinforcement area of the downstream slope of Zipingpu earth-rock fill dam using the mortar masonry facing after “5.12” Wenchuan Earthquake is determined to be in the dam slope area above 3/4 dam height.