Advanced Materials Research Vols. 838-841

Abstract: The building operations of cast-in-place structure mostly need to have a certain shape of cast-in-place soldier piles. The cast-in-site soldier pile model proposed in this study includes a baseboard, stepped holes set in the central part of the baseboard, and a pile body set on the stepped surface of stepped holes. The pile body can be installed at the location of stepped hole on the baseboard during the construction process, and then solidification and compaction operations shall be taken on the cement paste inside the pile body through the pre-set vibrating hole. These results can increase overall support strength of the civil construction, and also facilitate the overall installation and transportation of this device and reduce the production cost by using the split-type baseboard and pile body.

Abstract: It was incomplete and may have missed some dangerous working conditions to select several typical working conditions only in traditional strength analysis of hydraulic excavator. Therefore, the paper proposes a strategy that takes the working conditions when the load at each hinge of working device reaches largest into account. The working device of a 21t hydraulic excavator was analyzed with finite element analysis method when comparing these working conditions with the traditional typical ones. The results come out that the largest stress of boom, arm and bucket under these conditions increased respectively by 4.6%, 5.6% and 19.1% compared with the traditional most dangerous conditions. Consequently, in addition to the traditional typical conditions, it will be more safe and reliable to analyze the strength with the largest hinge loads conditions.

Abstract: Transmission tower collapses in adverse weather conditions now and than,which always accompanied thunderstorm.The simulation of transmission collapse under downburst wind load is studied. The tower is modeled as an assembly of beamcolumn elements,fournode isoparametric curved element,and prestressed pole unit simulation insulator,using bilinear restoring force model to formulate the material nonlinear.Simulated downburst wind load time history samples,apply it as external load to the established transmission tower model.Analysis of transmission tower know that transmission towers destroyed in the lower part of the body of the Tower, compressive failure modes in the beam , causing transmission tower's final collapse.

Abstract: Chinese ancient architectures are valuable culture heritages for human beings, and most of these ancient architectures are timber structures.[ Since most of the survived ancient architectures were built long time ago and suffered all kinds of nature disasters, their structures were damaged severely, and needed to be effectively reinforced and repaired. As the key element of Huizhou culture, Hui-style architecture is the representative of Chinese ancient architectures. Based on Hui-style architectures current damage situations, this paper studies the strengthen methods and current study situations of the timber structure of the ancient architectures from beam, column, mortise and tenon joint, corbel bracket, retaining structure and other aspects. It also studies the shortage of the traditional reinforcement methods, and discusses the usage of the new reinforcement material CFRP in the timber structure of the ancient architecture. In the end, the writer believes that finding sufficient methods to ensure the reinforcement effect, overcoming the shortage of the traditional reinforcement method, as well as ensuring the original appearance of the components when carry out the reinforcement, is the direction of the reinforcement study of Hui-style architecture in the future.

Abstract: To study the ultimate load-carrying capacity of pipe-plate Vierendeel truss joints, the analyses of joint failure modes and parameter effects were undertaken using nonlinear finite element method and uniform design approach. The plate instability was included in the failure modes. Factors such as the pipe diameter, the pipe thickness, the plate width, the plate height, and the plate thickness were considered in the joint models. Three kind of loading conditions on the plate, the axial force, the moment, the composed loading of axial force and moment were analyzed. The relationships between the joint failure modes and the factors are achieved. The joint ultimate load-bearing capacity formulas are proposed by regression analysis. The effects of factors on the joint strength are illustrated.

Abstract: Prestressed concrete-filled square steel tube truss is the kind of truss whose upper chords and lower chords are respectively concrete-filled square steel tube and prestressed square steel tube. Four truss models as square steel tube truss, concrete-filled square steel tube truss, prestressed square steel tube truss and prestressed concrete-filled square steel tube truss were analysed by ANSYS, each of those truss models’ span has three variations. The result shows that the bar sections’ strength of square steel tube truss and concrete-filled square steel tube truss are far from reaching their design strength when the allowable values of deflection has reached l//400. Unlike the cases described above, when the bar sections’ strength of prestressed square steel tube truss and prestressed concrete-filled square steel tube truss has reached their design strength, their load-bearing capacity is 1 or 1.5 times higher than those cases above and their deflection has not reached the allowable values.

Abstract: To overcome the shortcomings of assembly lightweight steel structure residential system in our country. A new type of lightweight energy-saving composite wall is proposed, which is composed by light-gauge shaped steel and thin panel. In order to investigate the load-bearing behaviour and failure mode of the composite wall, 4 wall specimens in full ratio were designed and manufactured. The experiment study is carried out under lateral and vertical loads. The results show that the self-drilling screw integrate the light-gauge shaped steel and thin panel to bear loads. The decrease of self-drilling screw spacing can effectively enhance the load-bearing capacity of the composite wall, and the best choice of the self-drilling screw pitch is 150mm. The composite wall has good bearing and deformation capacity, and it is suitable for applying to light weight steel residential system in our country.

Abstract: Considering the elastic-plastic stage of steel constitutive relationship, the assumption that element is elastic perfectly-plastic is no longer valid. The yield function that considers the effect of trilinear model is derived by using section assemblage concept. Element with two subsprings at each end is presented to consider the effect of section stiffness and yielding. Based on the proposed yield function and element, an efficient nonlinear analysis method for steel frame with trilinear model is proposed. The proposed element has the same nodal degrees of freedom as conventional beam-column element by condensing the non-nodal degrees of freedom. Other factors influence the capacity of steel frames, such as shear deformation, residual stress, geometric and material nonlinearity are explicated. The efficiency and accuracy of the proposed approach are demonstrated through the numerical example.

Abstract: This paper reports on part of an ongoing experimental program at The University of Adelaide on the flexural behavior of FRP-high-strength concrete (HSC)-steel double-skin tubular beams (DSTBs). The results from three circular DSTBs that were tested as simply supported beams in a four-point bending setup under monotonic loading are presented. The experimental study investigated the influences of the inner steel tube diameter and the use of mechanical connectors on the steel tube on the flexural behavior of DSTBs. The results indicate that DSTBs are capable of developing very high inelastic flexural deformations. However, the results also indicate that slip between the concrete and the steel tube of the DSTB can be relatively large, unless the bond between concrete and steel tube is enhanced through the use of mechanical connectors. It was also observed that the flexural behavior of DSTBs is influenced significantly by the diameter and thickness of the inner steel tube.

Abstract: This paper investigates the ductility of SIFCON blocks with various structural measures adopted to further increase their ductility. Ten SIFCON blocks with various designs were tested using a compression machine to investigate their ductility. The variables examined included fiber alignment, confinement, perforation, and longitudinal bars. Results of the tests indicated that SIFCON blocks with confinement in the form of stirrups and additional perforation can produce better ductility than others.