Applied Mechanics and Materials Vols. 488-489

Abstract: Using the phase shift of reflection coefficient of SV seismic wave at the free surface of stratum, we derived the the shift time of total reflected SV seismic wave, given formulae of shift timeand drawn the curves of shift time. The results show that reflected wave of VS-wave exists negative shift;for glancing wave or angle of incidence being near the critical angle, a large shift can be caused , In other angle of incidence the shift is the same order of magnitude as the wavelength.

Abstract: Based on the natural environment of Gansu YuMen oilfield in china, aiming at the winter heating requirements for oil field duty room, using the solar heating system that make solar energy storage and auxiliary electric heating, selection of flat plate collector, tacking double working medium for heat exchange indirectly, use the antifreeze liquid as the hot working medium, use the water as the energy storage and heating medium. According to the room temperature and medium temperature, intelligent control system adjust and control the double medium circulation loop, automatic regulating the intermittent work time for auxiliary electric heating system, the problem of antifreeze and sand prevention be solved effectively in the extreme temperatures. Compared to the electric heater heating, it can realize energy saving and environmental protection, the energy saving effect more than 46%, having remarkable economic and social benefits.

Abstract: The effect of the notch depth on the impact properties of the adhesively bonded steel butt joint under the Charpy impact test is studied using both the finite element method (FEM) and experimental method. The results obtained from numerical simulation showed that the value of the peak stress Seqv increased first and then decreased evidently when the notch depth increased from 2 mm to 8 mm. Comparing the results with that from Izod impact test, it is found that the response time retarded about 0.02 ms and the peak value of the stress Seqv decreased evidently under the Charpy impact test. The results from the experiments showed that the effect of notch depth on the impact energy absorbed by unit area of joint is as same as that from the Izod impact test.

Abstract: The response of the equivalent stress (Seqv) in adhesively bonded steel butt joint and the adhesive bondline during Izod impact test is studied using the finite element method (FEM) software ANSYS. The results obtained show that the highest value of the stress Seqv almost higher than the yield strength of the adherend reached within about 0.1 ms. The contour diagram of the stress Seqv is symmetrical to the axis along the half height of the specimen both in whole adhesively bonded steel butt joint and the adhesive layer. The peak value of the Seqv in adhesive increases first and then decreased when the action of the impact was over. The stress Seqv in both ends of the specimen kept to a relative lower value during impact procedure.

Abstract: The paper has a discussion of forward problem and inverse problem for beams in strength of materials. Known load case of a beam can certainly determine its shearing force diagram and bending moment diagram, but conversely, there may be a variety of statically determinate or statically indeterminate constraint conditions. Furthermore, the solution from statically indeterminate constraint conditions doesnt agree with the given shearing force diagram and bending moment diagram in a general way.

Abstract: A novel high durability epoxy asphalt concrete for bridge deck pavements is introduced in this paper, including the manufacturing process of epoxy asphalt binder and laboratory evaluation for this material. Various laboratory tests were conducted to evaluate the pavement performance of the materials, such as fatigue test, wheel tracking test, moisture susceptibility test and thermal stress restrained specimen test. Test results show that epoxy asphalt concrete has 20137 cycles/mm dynamic stability at 70°C, and-28.4 °C fracture temperature. The fatigue equations of epoxy asphalt concrete at different temperatures were obtained. Findings from the research indicate that the epoxy asphalt concrete is a suitable material for the pavement of long-span steel bridges in China due to its profound performance.

Abstract: In order to comparatively study the effect of warm mix modifiers on the road performance of guss asphalt, the guss asphalt mixtures, whose asphalt aggregate ratio were 8.5%,9.0%,9.5% respectively, were mixed with 0%,1%,2%,3% of the RH and Sasobit warm mix modifiers. Then by means of Lueer test, penetration test, wheel track test and low-temperature bending test, the performance of guss asphalt were evaluated. The test results show that: RH and Sasobit can effectively improve the workability of guss asphalt; RH is better than Sasobit in reducing viscosity of guss asphalt; RH reduces the high-temperature properties of guss asphalt; On the contrary, Sasobit can improve the hightemperature performance of guss asphalt; RH and Sasobit have an adverse impact on the crack resistance of guss asphalt in low temperature, so their content should not too high. Guss asphalt has characteristics of high construction temperature and energy consumption. In order to reduce construction temperature, based on energy conservation, low-carbon emission environment, reduce the aging of asphalt principle, warm modifiers could be used to reduce the viscosity of guss asphalt at high temperatures^[1-5]. Sasobit modifiers imported from Germany are used much more to improve the workability of guss asphalt. In this paper, 0%, 1%, 2%, 3% RH and Sasobit warm mix modifier were mixed with the aggregate ratio of 8.5%, 9.0%, and 9.5% of the Guss asphalt to compare and analyzed the performance of those two warm modifiers on Guss asphalt.

Abstract: The compatibility of rock asphalt modification agent and matrix asphalt was excellent, while different contents of the rock asphalt had great influence on the mechanics properties of mixture. Based on the aggregate grade of the AC-20 mixture, the mechanical properties of the matrix asphalt mixtures and the rock asphalt mixtures with different quantities of rock asphalt were studied by laboratory tests, including the high-temperature stability, low-temperature anti-cracking performance and water stability. This research is to give reference for the proper rock asphalt quantity of the mixture.

Abstract: Using finite element method and D-value method, this paper analyzes on force calculation of the special-shaped column frame structure,and obtains shear force and displacement value of the special-shaped column frame structure under the lateral earthquake action. The two methods of calculation results are compared and analyzed, and the results showed that finite element method is an effective method of calculating special-shaped column frame structure.

Abstract: Through analyzing concrete gravity dam structures mechanical characteristics in construction process and operating process, this paper adopts finite element method to carry out structural analysis for concrete gravity dam of Shachang reservoir. Deducing distribution law of the dams stress and displacement in construction process and operating process. Analysis results show that, concrete gravity dam of Shachang reservoir is reasonable, it meets the requirements for design. The analysis results provide a certain reference for design and construction of concrete gravity dam structure.