1引言砾质土是一种以粘性土和大于5mm的砾石组成的混合料，当砾石含量在一定范围内，且压实到最大干容重时，具有渗透性小，压缩性低，抗剪强度高等特点，是一种良好的筑坝材料，既能作为防渗材料，又能填筑坝壳，而且还便于施工，尤其对于雨季施工，比粘性土方便得多。此外， 1 Introduction Gravel soil is a mixture of cohesive soil and gravels larger than 5 mm. When the gravel content is within a certain range and compacted to the maximum dry bulk density, it has the advantages of low permeability, low compressibility and shear strength Higher characteristics, is a good dam material, both as impermeable material, but also fill the dam shell, but also easy to construct, especially for the rainy season construction, much more convenient than the clay. In addition,