绢云母片岩是一种易崩解的片岩填料，在大气的长期干湿循环作用下，性能极易发生衰减、弱化。通过开展干湿循环前后不同初始最大粒径绢云母片岩的加州承载比试验和回弹模量试验，探讨其强度变化规律，并结合颗粒分析试验，从崩解的角度解释上述强度变化原因。结果表明，绢云母片岩在经历10次干湿循环作用后颗粒再无明显崩解，粒径为10 mm的颗粒可作为其崩解强弱的分界点，粒径大于10 mm的颗粒崩解较快，粒径小于10 mm的颗粒崩解较慢。绢云母片岩的回弹模量在初始最大粒径为5～10 mm时较大；而其承载比在初始最大粒径为10～20 mm时较大。结合崩解特性，选取初始最大粒径10 mm作为绢云母片岩路基填筑的控制粒径。

Sericite schist particles are easy to disintegrate. Their performance can decay and weaken easily under long term wet-dry cycle effects. Both California bearing ratio (CBR) test and resilient modulus test (MD) are carried out on sericite schist particles with different initial maximum sizes. The strength variable characteristic is gained. Meanwhile, the paper reveals the interior disintegrated mechanism joined with particle size distribution curves. The results show that sericite schist particles don’t disintegrate obviously any further after they are subjected to more than 10 times wet-dry cycles. Moreover, they disintegrate rapidly if their particle sizes are greater than 10 mm. They disintegrate slowly if their particle sizes are less than 10 mm. The initial maximum particle size ranges corresponding to the strength peak value are 5-10 mm and 10-20 mm for CBR test and MR test, respectively. Hence, the initial maximum particle size of 10 mm could be recommended as controlled size for using sericite schist particles as subgrade fills.