Filter criteria for gravelly clayey soils with cracks

The gravelly clayey soils are commonly used as seepage resistant materials in high embankment dams. The core of the high embankment dam may crack owing to the layered construction placement or arch effect of the core. However, the filter design criteria for cracked gravelly clayey soils are not found. The filter tests are conducted using cracked gravelly clayey soils with different gravel contents and filters with different gradations and dry densities. The existing filter criteria for gravelly clayey soils are summarized and compared with the test results. The results show that the existing filter criteria cannot fully satisfy the need of filter design for cracked gravelly clayey soils. Based on the results of the tests and comparative analyses, the filter criteria for cracked gravelly clayey soils are proposed considering the combination seepage resistant mechanism of cracked gravelly clayey soils and the filters. The verification using the filter test results shows that the proposed filter criteria can be used for the filter design of cracked gravelly clayey soils with different gravel contents.