The Influence of Slab on Yield Mechanism of RC Frame Structure

"Strong column weak beam" form of frame structure is widely considered to be a reasonable framework structure yield mechanism in the seismic damage. The current structure design is mostly on the basis of that yield mechanism for structural seismic design. Generally the structural engineers ignore the bearing capacity contribution of frame beams that comes from the slab in the seismic design. The structure engineers considered the slab as a rigid component and simply calculate the slab stiffness by magnification factor method, which ignores the core of the problem. This paper analyzes mainly the influence of the destruction of slab form frame structure , studying further how slab affect the yield mechanism of frame structure, and explores the destruction form of difference between two models after analyzing two structure models by the method of Push – over. It shows that the existence of slab make the yield mechanism of RC frame structures different from the design.

The Study on Mechanical Property for Welded Haunch-Reinforced Seismic Connections of Steel Frame

To study on the mechanical property for haunch-reinforced seismic connection, the simplified calculation model of haunch connection is introduced. The force analysis of beam with haunch connection is carried through to research value influence on mechanical property of haunch connection; Combining American design specification with Chinese design specification, the design procedure for welded haunch connection is shown, and the differences in design between two countries are summarized. At last, it is studied through beam-column joints case analysis that the influence of the different node parameter on the mechanical property of haunch connection. The results can be got that with the increase of thevalue, the beam moment at column face becomes smaller, which will be better to protect the beam form brittle fracture. But if is larger than one,beam web shear in the haunch region will increase. In the design the reasonable value should be close to one but less than two. When haunch height is invariant, with the increase of haunch length,became smaller; the value and the top and bottom beam flange groove weld stress reduce gradually; The required minimum section area of haunch flange became larger; The axial force of haunch flange and haunch web shear increase gradually. The reasonable haunch length should be as close to the middle of the (0.5 to0.6) times of height beam as possible. The reasonable haunch flange section area should make close to, such materials are made full use. Key words: haunch connection; force analysis; parameter of reinforced-plate; mechanical property

Development and Evaluation for Improvement of a Beam-Form Support in Korean Building Constructions

This study developed the improvements to supplement problems of the existing beam-form support, which was evaluated by experts. By evaluating Improvement 3 and the existing support in the aspect of performance and construction cost, its applicability was reviewed in the field of construction work. Comparing the developed beam-form support with the existing support, thus, its constructability, safety and durability were more excellent while the construction cost was similar to each other, which means that it is possible to be applied to the field. However, it is considered that we need to have more additional researches on construction procedures that can be applied to building beam-form and development of members with economic feasibility.

Dynamic Characteristics Study of U-Beam Applied in Rail Transit

The Train-Track-Bridge coupling vibration theory was applied to analyze the dynamic characteristics of a U-beam serviced in Chongqing Rail Transit Line 1 in China. According to the analysis, for the U-beam form of this opening cross-section, the traditional 3D beam element model can only reflect the first-order vibration mode, but neglect the coupled local flexure and torsion vibration characteristics; the 3D beam element model overestimates the lateral stiffness of the bridge, and underestimates it’s lateral vibration; the 3D plate element model is reasonable in dynamic analysis of opening cross-section structure; the vibration of U-beam dominates in the frequency range of f < 250, which is accurate and efficient to take into account this frequency range in the analysis of noise radiated by bridge structure.

Strain field measurement of plate-like defect in silicon

Strain contrast around the precipitate in crystalline solid has been interpreted as due to the elastic distortion of the matrix around the precipitate. Adding the displacements into the dynamical equations of diffraction contrast in the 2-beam form developed by Howie and Whelan, and using the column approximation to calculate the intensities point by point, it is possible to obtain the intensity map of the strain contrast for a particular strain parameter ε. Ashby and Brown showed that the strain-measuring methods for the simplest case of spherical precipitate can be extended to determine the strain of the plate-like defect (PLD) normal to the plane of the plate. Most of the precipitates in silicon induce strain fields in the surrounding matrix with PLD the largest. In this abstract, we are trying to measure the strain field ε of PLD in silicon by matching the experimental and simulated images.