Analysis Of Steel-Rcc Composite Deck Bridge

: In the literature, provisions for analysis and design of steel-RCC composite deck type truss and cable-stayed bridges do not exist. A composite deck type truss bridge model is analyzed using STAAD Pro V8i software and a model with the same dimensions is tested in the laboratory. The experimental test results are used to validate the STAAD analysis results. Bottom chord strain and mid-span deflection of the composite bridge model as found from the STAAD analysis and the laboratory experiment closely tally with each other. This validates the standard STAAD analysis results. However, in the top chord member, due to shrinkage cracks in the deck slab concrete, the experimentally recorded strain is higher by about 100% than the STAAD analysis result. Shear force in studs is considerably large near supports and joints as compared to the midsection. Therefore, the design of shear studs may be carried out based on the shear forces in the studs found from the STAAD analysis. Thus it is recommended that STAAD or any other standard finite element analysis software can be used for analysis and design of the composite bridges.

Behavior of Longitudinal Plate-to-Rectangular Hollow Structural Section K-Connections Subjected to Cyclic Loading

This study investigated the behavior of longitudinal plate-to-rectangular hollow section (RHS) K-connections to which concrete-filled composite branch members were jointed. At the connections, longitudinal plates with or without chord face stiffener were welded to the RHS chord member and the branch members were connected to the longitudinal plates by bolting (slip-critical connection). Cyclic tests were performed for three longitudinal plate-to-RHS K-connection specimens. The tests showed that the connection behavior was dominated by the plastification of the thin chord face and by the slip and hole-bearing resistance of the bolted joint. Chord face plastification was prevented or delayed by using the stiffened longitudinal plate. The strengths of the plate-to-RHS K-connections with or without the chord face stiffener, depending on the governing limit states, were estimated in accordance with current design codes, and the results were compared with the test results.

Experimental Study on the Static Behavior of Reinforced Warren Circular Hollow Section (CHS) Tubular Trusses

For truss structures, the question of whether to weld hidden welds or not has been controversial. In the actual construction process of truss structures, the members are usually spot welded in place on the assembly platform, and then welded as a whole, while the hidden welds of the truss are not welded, especially for small pipe diameter trusses. Furthermore, in this study, under hidden weld unwelded conditions, two kinds of reinforcing method (adding a half outer sleeve on each joint and filling concrete into the chord members) are adopted to achieve the purpose of strengthening the truss. Therefore, this paper presents an experimental study on the static behavior of four types of Warren tubular trusses made of CHS members. These four types are (1) T-HW: The truss with hidden welds welded; (2) T-HN: The truss with hidden welds unwelded; (3) TS-AS: The truss strengthened on the basis of T-HN by adding a half outer sleeve on each joint; (4) TS-FC: The truss strengthened on the basis of T-HN by filling concrete into the top and bottom chord members. The mechanical behavior, failure mode, bearing capacity, and load-displacement of all specimens were investigated. The surface plasticity of the bottom chord member, the weld fracture around tubular joints at the bottom chord member, and the bending deformation of the bottom chord member were observed in the tests. Compared with the T-HW specimen, the load carrying capacity of the T-HN specimen decreased by 18%. On the other hand, the T-HN specimen has better deformability than the T-HW specimen. The reinforcing method of adding a half outer sleeve on each joint and filling concrete into the chord members can effectively improve the load carrying capacity and stiffness of the truss, thus reducing the overall deformation of the truss, but the reinforcing method of filling concrete into the chord members is more efficient.

Study on Seismic Performance of Space KK Type Joint of UHV Transmission Steel Pipe Tower

In order to study on the bearing capacity and energy dissipation capacity of the circular tubular KK-joints under the cyclic loading, the models of space KK tubular joints are established by using ABAQUS finite element software. The influence of outer diameter ratio of branch member to chord member, diameter to thickness ratio of chord member, the axial angle between branch and chord member, horizontal angle between branches and the thickness ratio of stiffeners to chord members are studied. The results show that the joints have the excellent bearing capacity and plastic deformation ability. The smaller the ratio of diameter to thickness and the axial angle of the chord, the better the hysteretic performance of the joints. The larger the ratio of the outer diameter of the chord, the transverse angle between the branches and the thickness ratio of the connecting plate to the chord, the better the hysteretic performance.

Experimental and Numerical Analysis on the K-Joint Laterally Impacted by a Knife Edge Indenter

Experimental and numerical studies are carried out to investigate the performance of K joints of a jack-up structure under lateral impact loading. The dynamic response is studied in a drop weight impact testing machine using three different falling heights and the failure mode and local damages of the specimens were investigated. The experimental results show that the force-time curves corresponding to the three falling heights have similar tendency during the plastic deformation process and three stages are observed in each force-time curve. The failure mode of K joints is commonly concave at the impacted area of the chord member and is buckled at the section near the mid-span of the branch members. When both ends are fixed, the chord member shows the conventional plastic failure mechanism due to bending. Numerical simulations that consider the material nonlinearity are conducted to investigate the performance of K the joints. Coupon tests of the steel are conducted to obtain the mechanical properties under both quasi-static and dynamic conditions; and these test results were then inputted as material properties for the above numerical simulating. Good agreement was achieved between the responses obtained by the FEM and the experimental results.

RHS-to-RHS axially loaded X-connections near an open chord end

In all truss-type welded hollow structural section connection design procedures, the chord member is assumed continuous on both sides of the branch. New limits of applicability have recently been advocated, which specify minimum end distances from an open chord end to achieve the full connection strength. To investigate their suitability for rectangular hollow section (RHS) connections, an experimental program consisting of 12 RHS-to-RHS X-connections subject to branch axial compression was undertaken. For connections near a chord end, a modified yield line mechanism controlled. A proposed analytical model is derived, and by evaluating against the experimental results, is shown to accurately predict the yield loads. An EN 1993-1-8 amendment, transcribed from circular hollow section connections, is deemed excessively conservative, and a closed-form solution for the end distance, presented herein, is recommended for use with RHS connections. Alternatively, providing a cap plate is determined to be an effective stiffening method.

Comparison on Harmonic Response Analysis of Two Kinds of Air Cooling Fan Bridge Model

The fan bridge is the important supporting structure in the air cooling system, is mainly influenced by the fan vibration. By using ANASYS soft ware, analyzing the two different structures of Fan Bridges harmonic response, and comparing them, the conclusion is that the style that Bearing skew support is connected with the upper chord member say truss structure can effectively reduce the adverse effects of equipment vibration on the structure.

Numerical Analysis of Bearing Capacity to Q690 Tubular Joints Enhanced by Inner Sleeve

Simple joint is a common connection in tubular structures, it refers to one or more components soldered directly on the surface of the other member. Local buckling occurs in panel zone when the joint under heavy load, such local buckling will reduce the bearing capacity and stiffness. In order to improve bearing capacity of tubular joints, the joint needs to be strengthened. In this paper, the bending performance of the joint will be enhanced by welding a sleeve inner the surface of panel zone of chord member. By ANSYS finite element program, the bearing capacity of the joint with different parameters of inner sleeve was analyzed. The results showed that compare to sleeve length variation, bearing capacity of the joint experiences obvious change with variation of sleeve thickness.

Numerical Analysis of Bearing Capacity to Q690 Tubular Joints Enhanced by Tile Shaped Plate

Simple joint is a common connection in tubular structures. Local buckling occurs in panel zone when the joints bear heavy loads, and local buckling will reduce the bearing capacity and stiffness. In order to improve the bearing capacity of tubular joints, the joints need to be strengthened. In this paper, the bending performance of the joints will be enhanced by welding a tile shaped plate outside the surface of panel zone of chord member. By ANSYS finite element program, the bearing capacity of the joint with different tile shaped plate was analyzed. The results showed that the bearing capacity of the joints experience obvious change with variation of thickness, whereas the bearing capacity has no change with variation of radian.