China′s dual economic structure is characterized by its own structural rigidity,which is expressed by the specific feature that the transformation of China′s dual economic structure is ′solidified′,namely,the employment transformation of the rural labor force lags seriously behind the production value transformation,and it is difficult to narrow the gap between urban and rural areas,etc.

The analysis showed that this phenomenon were due to the structure rigidity deficiency of flame tube head shield.

According to the current status and the actual working conditions on the protection device for tram free-sliding in slant well,on the basis of energy absorption principle of materials and structures the working principle based on semi-rigid structure was put forward,and the blocking device with wavy gate structure was designed.