Numerical simulation of seismic damage and cracking of concrete slabs of high concrete face rockfill dams

摘要

Based on the damage constitutive model for concrete, the Weibull distribution function was used to characterize the random distribution ofthe mechanical properties of materials by finely subdividing concrete slab elements, and a concrete random mesoscopic damage model wasestablished. The seismic response of a 100-m high concrete face rockfill dam (CFRD), subjected to ground motion with different intensities, wassimulated with the three-dimensional finite element method (FEM), with emphasis on exploration of damage and the cracking process ofconcrete slabs during earthquakes as well as analysis of dynamic damage and cracking characteristics during strong earthquakes. The calculatedresults show that the number of damaged and cracking elements on concrete slabs grows with the duration of earthquakes. With increasingearthquake intensity, the damaged zone and cracking zone on concrete slabs grow wider. During a 7.0-magnitude earthquake, the stress level ofconcrete slabs is low for the CFRD, and there is almost no damage or slight damage to the slabs. While during a 9.0-magnitude strongearthquake, the percentages of damaged elements and macrocracking elements continuously ascend with the duration of the earthquake, peakingat approximately 26% and 5% at the end of the earthquake, respectively. The concrete random mesoscopic damage model can depict the entireprocess of sprouting, growing, connecting, and expanding of cracks on a concrete slab during earthquakes.