Point out flet mechanism of aggregate and pitch from two respects of physics and chemical performance , probe into internal cause and external cause on road surface further .
从物理性能和化学性能两方面指出集料和沥青的粘结机理，进一步探讨路面产生水损坏的内因和外因。
I flet very sad when they tired .
当他们累的时候我感到很伤心。
flet