The weathering of soft rock was systimatically analyzed through measuring its microsturcture, microporosity, macrofissure, and the physico chemical properties.

The macroscopic subdivision of grains with different orientations was characterized in detail by using EBSP technique.

In this paper, cracks in concrete are divided into micro-cracks and macro-cracks.

First,the crack initiation and expansion processes were divided into three phases: micro-scale thinness sight crack,CT scale crack,and macroscopic crack.

Here so-called repair is that joining specific ceramic raw materials among the macroscopic crack, which were produced after sintering in ceramic products, then re-sintering in less than matrix sintering temperature, thus macroscopic crack is closed, and does not influence the basic function of use of the original ceramic products.

The results show that the microscopic crack is caused by the relatively big stress when cutting the forge piece,whereas,the interactions berween thermal stress and structural stress in heat treatment promote the expansion of these microscopic crack into macroscopic crack.