To analyze mechanics of polyurethane rubber layers in roll bending process,a new concept of converted elastic modulus for polyurethane rubber is put forward to define the elastic modulus of polyurethane rubber changed during forming and the expression of Eeis derived.

The flexural deformation behaviors and the degradation law of the breaking resistant elasticity modulus du.

The bending elastic modulus of different high bending strength pavement concrete are analyzed,and the regression equation between bending elastic modulus and bending strength most in use is presented.

With the finite element method,the bending stiffness of twin-block ballastless track with double combined slabs composed of a track slab and a support layer was investigated through changing the elastic modulus and thickness of the support layer and the interval between cracks,and the reduced elastic modulus of the cracked support layer was obtained.

This paper presented a method that combination modulus of pile and soil complex under effects of pile and soil interaction,that effects of pile nearby and pile groups was considered.

Based on some reasonable hypotheses and the stress-strain relationship of concrete obtained by the “adjusting valid modulus depending on age” method, a compact formula to calculate the conversion elastic modulus of the core concrete is presented, which can consider both the influences of creep and the interaction between steel and concrete.

Applying the conversion elastic modulus and conversion coefficient of load, the computer model for calculation of creep secondary internal force for continuous beam bridges is established.