Applied Mechanics and Materials Vols. 405-408

Abstract: In order to investigate the simple calculative method of channels with complex edge stiffeners for the elastic distortional buckling stress under axial compressive load, a total of 90 cold-formed thin-walled steel channels with Σstyle web stiffeners and complex edge stiffeners , channels with complex edge stiffeners and intermediate V type stiffeners in the web were analyzed by finite strip software CUFSM. The influence of the parameters for the elastic distortional buckling stress was analyzed. Simplified formulas for calculating the elastic distortional buckling stress of Σstyle channels with complex edge stiffeners, channels with complex edge stiffeners and intermediate V type stiffeners in the web under axial compressive load were provided. The availability of the formulas was verified.

Abstract: In order to research the simplified formulas of bending steel channels with complex edge stiffeners for their elastic distortional buckling stress, each 70 members for lipped channels with complex edge stiffeners, Σ style channels with complex edge stiffeners and channels with complex edge stiffeners and intermediate V type stiffeners in the web were numerical analyzed by the finite strip software CUFSM. Based on the existed expression for local bucking and introducing distortional buckling coefficient, each of the suggested simplified formulas for distortional buckling stress of the above members were summarized. Besides, formulas for lipped channels with complex edge stiffeners and channels with complex edge stiffeners and intermediate V type stiffeners in the web were united as one. All the formulas were confirmed for their availability.

Abstract: Vibration is a priority in the field of construction machinery in the process group dynamic load processing of different materials. Presented here are models with basic mathematical relationships that we utilize to describe phenomena in the task of modeling any process of dynamic loads acting on the treated medium. In the presented material, diagrams are considered necessary when dealing with specific parameters modeling of real processes of rheological effects on the body: elastic-inertial, viscous-inertial and yielding-inertial on, for example, treatments of concrete mixes.

Abstract: This paper presents experimental results of a series of large-scale reinforced concrete circular and square columns tested under lateral cyclic displacement excursions while simultaneously subjected to constant axial load. All the specimens contained only minimal transverse steel and were then retrofitted with CFRP or GFRP jackets except control specimens. The measured hysteretic loops of the moment vs. curvature and shear vs. deflection relationships are reported for each specimen. It was observed that both CFRP and GFRP wrapping could provide effective confinement and significantly improve the seismic performance of columns. The effectiveness of FRP in enhancing column ductility relates more closely to its tensile strength than stiffness, thus the application of GFRP confinement to concrete columns is promoted due to obtainability and economical concern.

Abstract: This paper presents finite element analysis on cold-formed steel-section columns with complex edge stiffeners and web holes under axial compression. A total of 18 channel models with different parameters such as length, thickness and flange width are simulated. Failure modes, the ultimate load and the stress distribution around web holes are researched. The analysis results show that, the main failure mode of-section columns with complex edge stiffeners and web holes is distortional buckling. The carrying efficiency is higher as the thickness-width ratio increasing. Because of perforations on the web, the position of the max stress changes from the web near the mid-height of the specimens to the location adjacent to holes.

Abstract: Based on the experiment research of three concrete beam-column joints strengthened with anchored Carbon Fiber Reinforced Polymer (CFRP) under low reversed cyclic loading , this paper studys on the mechanical properties and deformation characteristics of reinforced nodes, and also makes the anylasis of the influence mechanism of shear bearing capacity of beam-column joints with longitudinal land transverse carbon fiber reinforcement amount in the beam-colunm ends. The results show that: the bolt-plate lock-anchored CFRP hoops can effectively delay the debonding of the longitudinal CFRP at the end of beam, significantly increase the energy dissipation capacity of the joint.

Abstract: The shear behavior of 18 different groups of hybrid fiber (steel fiber and polypropylene fiber) reinforced HPC deep beams and 2 groups of HPC deep beams without fiber were discussed through experimental study and nonlinear finite element analysis. The shear tests were made under the static load and the finite element analysis software ABAQUS was used in numerical simulation. Results illuminate that hybrid fiber can significantly increase the diagonal cracking load and the ultimate shear load of deep beams although it can not change the brittleness of shear damage. Good agreement are found between test results and simulative results, including failure mode of hybrid fiber reinforced HPC deep beams, load-displacement curves, stress distribution of steel bars and concrete, etc.

Abstract: This paper examines the effect of pitting corrosion of prestressing steel strands on flexural strength of prestressed concrete (PC) beams in marine environment. A reliability-based methodology for the prediction of time to structural failure after corrosion initiation was proposed and probabilities of failure are evaluated using FORM as exampled by a high-speed rail PC box beam. The methodology presented in this paper can be used as a tool for structural engineers and asset managers to assess a corrosion-affected concrete infrastructure and make decisions with regard to its maintenance and rehabilitation.

Abstract: With the development of science and technology and the improvement of people's living standard, Natural gas has been widely applied to daily life. But the sharp increase in natural gas explosion accident. In this paper, Analysis of the effects of gas explosion on the structure, and the safety of the structure was evaluated. By detecting the damage phenomena of gas explosion in a civil building, use the characteristics and law of the gas explosion and finite element simulation analysis method.

Abstract: According to the fact that the research about temperature stress of steel structure is few. In this paper, a factory steel truss which support raw material pipeline as an example, taking the 34-hour on-site continuous strain test on the steel truss caused by sunshine temperature. The experimental results show that the temperature stress has a great influence on the internal force of steel truss. And the results can provide a basis for engineering design.