Formulas were put forward for calculating ultimate resisting moment on negative moment region and limit load of beams.

On the basis of numerically simulating the working mechanism of the key grooves,the static and dynamic analyses are made herein on the effect from the arrangement of the key grooves on the ultimate resisting force and dynamic response of both the flat bottom slab and inverted arch bottom slab through changing the connection shape of the structural joints in between the blocks of the bottom slAbs.

By the study on whole strength and parameter optimization for the bearing,the theory analysis and the test show that the ultimate design method can largely increase carrying ability and service life of the bearing without changing bearing material and manufacture technology,and the method can decrease bearing weight and reduce the material consumption.

Dimensional optimization of reinforced circle plates and rings subject to symmetrical loads is presented based on duality between limit analysis and limit design,employing a model combining Morley curvature field in layout optimization and Powell Constrained Variable Metric Algorithms(CVM) in NLP.

Based on the experimental research,the limit design method for the reinforced concrete L-shaped slab under the action of uniform loads is presented, the loading transmission and span of oblique strip are discussed.

According to the limit flexural intensity of beam,and combined shear stress and overall stability computation,the largest coal and gas outburst intensity that anti-outburst grid can afford at the limit state could be conversely calculated,thus formed the limit design method of the an.