Advanced Materials Research Vols. 374-377

Abstract: By the method of the experiment and the finite element, the production, development regulation and location of the plastic hinge of widened beam flange connections were studied. The test results showed good agreement with FEM results and proved the finite analysis reliable. The test specimens were designed as the base samples. By choosing some different main references relating to section shape change of widened beam flange connections, a series of finite element specimens which include eighteen direct arc widened beam flange connection and eighteen welded side-plate widened beam flange connections were derived from the base samples. The influence of widened beam flange depth, length and distance on plastic hinge distribution is discussed respectively, at the same time, the plastic hinge location range was given and practical section design method of widened beam flange connection is provided by revising the parameter of plastic hinge center location ls.

Abstract: In order to implement the bi-level optimization strategy-collaborative optimization (CO) to bridge design, bridge optimization design process is subdivided into three subsystems in terms of component-oriented decomposition: superstructure subsystem, bearing subsystem and substructure subsystem. For system level, target function is formulated with the total direct construction cost, and inequality constraints induced relaxation factors are adopted to relax the intersubsystem consistency constraints. For subsystems, target functions are formulated with discrepancy expressions and constraints are formulated according to corresponding codes demands respectively. The feasibility and validity of the proposed approach are examined with an optimization process of reinforcement concrete box girder bridge. Optimization results from proposed approach are compared with that from mono-discipline optimization. The proposed approach shows high computing efficiency than mono-discipline optimization methods when achieving same optimization results.

Abstract: The reliability evaluation for the bridge in service can provide a scientific basis for decision-making in bridge repair and reinforcement. A comprehensive method for reliability evaluation was introduced in this paper based on a long span continuous bridge with variable section evaluation. Appearance survey of the bridge, concrete strength and carbonization test, static test and dynamic test would be done as well as the finite element simulation model to determine the properties of the bridge for reliability evaluation. The relationship of the natural frequency stiffness evaluation method and the effective coefficient method would be established in this paper based on the test results. Based on the static and dynamic test, we classify the bridge as class 3 while the bending stiffness is good, the dynamic rigidity is a little weak, and the damping coefficient a little larger.

Abstract: With the increasing urbanization and the expansion of the city these years, the urban stormwater flood emerge frequently in all major cities in China and cause a huge casualties and property losses. Discuss the ideas and measures of prevention and control of urban stormwater flood by analysis the reason of the formation. Set up the concepts of stormwater resources not only to give priority to the emissions ideas. Bring the ideas of discussing the problem of stormwater resources from the aspect of innovation of rural and urban planning and design system. According to the comprehensive utilization of urban stormwater and emissions which each link specific characteristics, the author tried to establish an innovative of urban planning and design system to cope with the current situation which urban rainwater flooding frequently.

Abstract: The microwave interferometer used in the present study is capable of multiple-point displacement measurements. In this paper, a general review of the principle and capacity of such an instrument is given. The vertical displacements of the Ai-Lan bridge corresponding to ambient vibration due to traffic loads are remotely monitored . Several modal shapes of the whole bridge are precisely identified by linking the mode shapes of seven sequential measurements.

Abstract: High strength steel sections have been increasingly used in buildings and bridges, and steel angles have also been widely used in many steel structures, especially in transmission towers and long span trusses. However, high strength steel exhibits mechanical properties that are quite different from ordinary strength steel, and hence, the local buckling behavior of steel equal angle members under axial compression varies with the steel strength. However, there is a lack of research on the relationship of the local buckling behavior of steel equal angle members under axial compression with the steel strength. A finite element model is developed in this paper to analyze the local buckling behavior of steel equal angle members under axial compression, and study its relationship with the steel strength and the width-to-thickness ratio of the angle leg. The finite element analysis (FEA) results are compared with the corresponding design method in the American code AISC 360-05, which provides a reference for the related design.

Abstract: Abstract:Along with the fast increasing of maintenance demand, the problems associated with maintenance and reinforcement decision-making for deteriorating bridges such as maintenance strategy optimization have been present research focus. The solutions to these problems have inspired a considerable amount of research, one particular area being the application of evolutionary search algorithms such as the genetic algorithm (GA). This paper begins with a brief overview of bridge maintenance strategy optimization followed by a review of the current state of research in applying evolutionary techniques to solving this problem.

Abstract: The fitting curve given by least square method is applied in numerical analyzing. The results from semi-unrestrained and completely restricted modeling show convex deformation and damage on oblique section clearly. Advanced virtual experiment illustrates the differences between loading with displacement and pressure, due to the phenomenon that pressing by force will cause deformation on top surface but displacing load wouldn’t. The fitting idea by orthogonal base function will provide a widely road for studying the constitute law of concrete material. Otherwise, the progress of solving nonlinear function is discussed for designing new numerical analyzing tool, and the frame of programming based on nonlinear method is obtained

Abstract: Combined with the practical engineering of Changjiling tunnel in Guangdong highway, we analyzed the influence of different dimensions and positions of karst cave on deformation of the double track tunnel surrounding rock by FLAC3D. As the cave located above or below the left tunnel, the simulated result indicated the deformation characteristic of surrounding rock was similar. That was the Z-displacement took great part. And the displacements of the key points at the cross section of left tunnel decreased with increasing karst cave radius. But when the radius reached to a certain scale, the displacement also had enlargement trendy. On the contrary, the displacement of right tunnel′s key point increased with the increase of the cave radius, but the increased portion was minus to that of the left tunnel. When the cave located between left and right tunnel, horizontal displacement of the two tunnels surrounding rock increased and the Z-displacement decreased. And the displacement increased with the enlargement of size of karst cave. Meanwhile, deformation of the tunnel spandrel was asymmetric, that was, the displacement of tunnel closed to the caves was larger than the other.

Abstract: Property tax levying will make a huge impact on residential demand, residential supply, even the whole residential property market. It plays a vital role to the healthy and stable development of the residential property market. Although levying the property tax is very difficulty, it is the inevitable trend of development. In the long run, levying the property tax not only conform to the national interest, but also conducive to development of the real estate and the interests of residence buyer.