Applied Mechanics and Materials Vols. 477-478

Abstract: In lattice angle steel transmission tower, as the bolt diameter is small and member connection is relatively thin, lower clamping force is commonly used in bolted joint. It is common in lattice tower during full tower tests, joint slippage occur even under design load. However, traditionally trussed beam hybrid finite element model without explicitly considering slippage effects has been widely used in the analysis of the tower. In this paper, the HD-1 tower was experimentally studied under various static load cases, and several numerical models with including joint eccentricity and slippage are established. After comparing the theoretical analysis results and the experimental results, the following conclusions are presented: joint eccentricity almost has not effects on leg member axial force; Among all the studied load cases, joint slippage effects the leg member force most under torsional condition than the other load conditions; Numerical model with including joint slippage effects yield much better axial force results in leg member compared with experimental test results.

Abstract: Both finite element method and cable numerical calculation have their limitations in calculation of main cable shape for self-anchored suspension bridge. This paper combined the characteristics of the two methods, and worked out the cable shape and internal force of self-anchored suspension bridge though iterative computation. Sanchaji Bridge, a self-anchored suspension bridge in Changsha city, its main cable shape was calculated by this method. Calculating results show that the real shape of main cable fit the results well and we should carefully calculate the length of girder compression which influences the unstressed length of main cable and the position of hangers. The calculating method adopted in Sanchaji Bridge offered a reference for design and construction for similar bridges.

Abstract: This paper take a reinforced concrete frame structures storey-adding transformation as an example, analysising and calculating the whole structure adding layer before and after, then discussing the reinforcing measures of the column during the design of this processing. The using condition shows that reinforcing measures is very safe and effective that the project has adopted, and it can serve as a reference for the design of similar projects.

Abstract: Numerous bridges have to be lifted to meet increased navigation capacity. However, no relevant technical standard for the jack-up technique is yet available. This paper presents a study on the integral lifting of simply supported girder bridge which implements the finite element method. Finite element analysis provides a reliable basis in controlling construction. Research shows that stress concentration is evident near support points in the lifting process. Thus, stress monitoring is necessary. These points should be near to the bridge web. Moreover, beam span and section rigidity should also be considered when jacking up a bridge. The value of allowable error in the jacking-up process decreases with increasing beam span or decreasing section stiffness. Therefore, jacking up a bridge will be safer when section rigidity is large enough and beam span is not extremely long. This paper offers tremendous reference value with regard to engineering projects.

Abstract: In recent years, CFRP is widely used both at home and abroad. The numbers of tests about the research on CFRP reinforcing corrosion concrete are more than numerical simulation. In this paper, OpenSees has been used to do the numerical simulation on nonlinear analysis of the CFRP reinforcement corrosion concrete column aseismic behavior. And the results were compared with the tests. The results show that it can well predict seismic performance of CFRP strengthening corrosion concrete by choosing reasonable material bond-slip constitutive.

Abstract: In order to study the shear resistance and design method of hybrid fiber (steel fiber and polypropylene fiber) reinforced high performance concrete deep beams, the shear tests were conducted according to the orthogonal experimental design. The contributory factors such as the characteristic parameters of steel fiber (types, volume fraction, aspect ratio), the volume fraction of polypropylene fiber, the ratio of web horizontal reinforcement and the ratio of web vertical reinforcement were analyzed. Results illuminate that shear failure mode of hybrid fiber reinforced HPC deep beams are splitting failure and diagonal compression failure. Hybrid fiber can notably increase the diagonal cracking strength and shear strength of HPC deep beams. The diagonal cracking strength is increased by 5.6%~83.8% while the shear strength is increased by15.6%~35.2%. A formula to calculate the shear resistance of hybrid fiber reinforced HPC deep beams is put forward based on spatial strut-and-tie mode and splitting failure. Meantime test verification is carried out and the calculated results are satisfied.

Abstract: To ensure that the cable force tuning of Banfu No.2 bridge was carried out successfully, an incremental method for cable force tuning was presented, which took into account the cable-girder temperature difference. The cable forces were measured through frequency method. Before cable force tuning, all cable forces and temperatures of cables and girders were measured when the ambient temperature was stable, and these cable forces were taken as reference cable forces. During cable force tuning, the increment of cable force was regarded as the control quantity, while the displacement in the middle of main span was regarded as the verification quantity. After each stage, it was necessary to measure the temperatures of cables and girders and the displacement variation in the middle of the main span. To ensure the mechanical state of bridge was in control, all cable forces were measured after the 5^th, 10^th pairs of cables and all cables were tuned. In addition, the temperature-corrected cable forces were compared with the calculated ones, which showed the incremental method was not only accurate but also efficient.

Abstract: For application of FMT (ferrous mill tailing) to structural concrete, it is urgent need to study the bond behavior of reinforced bars with FMT concrete. In this paper, 72 pull-out tests of HRB335 steel bars from FMT concrete were carried out. The test phenomena and various factors influence on bond behavior were obtained. The results show that the bonding performance between deformed bars and FMT concrete is approximate to that of deformed bars and ordinary concrete. The results should provide technical support for application of FMT concrete in building structures.

Abstract: According to the actual structure of grouting sleeve, the ABAQUS finite element model of grouting-sleeve reinforcement-connection component was established. By changing sleeve-rib space, the influence of sleeve-rib space on the stress and the displacement distribution at grouting material were gotten. Numerical simulation shows that with the decrease of sleeve-rib space, the internal force distribution of grouting material tends to be uniform. Under axial tension load, with the sleeve-rib space of 14mm, the maximum stress of grouting material is lower than its strength, which makes grouting-sleeve reinforcement-connection component to be in a stable work condition.

Abstract: The simulation models concrete filled steel tubular arch was constructed by using a finite element software, the 1/4 vehicle model and vehicle vibration equilibrium equation were derived by D Alemberts principle, samples of each bridge roughness were created by using the discrete Fourier transform method, the effect of bridge roughness and vehicles speed on the impact coefficient of the suspenders. The results showed that the bridge roughness had a strong influence on the impact coefficient of the suspenders; the impact coefficient fluctuated with a raise of vehicles speed; the dynamic internal force of the suspenders obviously increased with the shortening length under the vehicle load. Theory basis can be provided for the fatigue fracture inclination of the middle and short suspender in the half-through and through bridge, and a reference can be provide for the bridge design, maintenance, management, survey and evaluation.