The bendingpoint of steel chains for mining is the center of stress, at which the shoulder fracture always occurs.
矿用圆环链弯曲点是应力集中点，肩部断裂发生于该点附近。
2
The model of switch calculated is built aiming to number 42 double arm elastic bendingpoint rail, system analysis is made for switching force and inadequate displacement.
Takada's simplified formula calculates the length of the start-bendingpoint to the fault according to Kennedy's method and the soil constraint is not considered in his finite element model.