Distributions of detention forces of ideal equal thread pitch casing connections presents parablic shape under axial tention, which kills the load bearing capability of casing connections.

By analyzing influence factor of tripping force, several measures that can steady tripping force of circuit breaker operation mechanism were stipulated in the case of no varying structure of circuit breaker.

Via analysis of factors which influence circuit breaker operating mechanism tripping force, the effective method to control tripping force is given, thus e.

The linkages in low voltage circuit breaker are analyzed based on the tripping force.

Based on the existing algorithm and through ascertaining the influence matrix of the tensile force in the construction of oblique pulling rope,the optimized stayed-buckle cable force is calculated at each stage of archrib hoisting phase of a model bridge during construction and the designed requirement is fulfilled through empty steel tube in falling state.

The decrease of clamping force of fastener, the gauge widening and the rail overturning are discussed.

Non-bracket and Cable erection is the main erecting arch ribs method of a long span concrete-filled steel-tube(CFST) arch bridge recently,but it requires to adjust the cable force over and over again,which increases the degree of construction difficulty and arch axis linear control trouble,delays the project limit time.

Research purposes: By summing up the advantages and disadvantages of using the torque balance method and the finite element "zero displacement method" to determine the cable force,the optimal calculation method is used for the Luobuxi Bridge to guarantee the linear accuracy in arch rib segment of the bridge and construction safety.

Taking Da-ning River Bridge in construction as the engineering background,the optimization analysis of cable forces and segmental cambers has been carried out during the process of arch rib segmental installment.