Advanced Materials Research Vols. 368-373

Abstract: It is difficult to apply the common nondestructive method to the pile with an inaccessible head condition. The Parallel Seismic test, however, is a promising method that can be used to deal with such difficulties. On the basis of the physical mechanism of P-wave and S-wave, comparisons of the characteristics of the volumetric and shear strain signals, as well as vertical and horizontal vibration signals have been made, providing the theoretical basis for adoption of P-wave and PS-wave as a combination.

Abstract: Some key technologies of neural network for structural damage identification, such as structural design of BP network, input parameter forms, training methods, learning rules and so on, are discussed. Modal parameters of a cylindrical shell structure under different support conditions are tested. Then these data are used as training samples for BP network, and depending on whether using random error, two different BP network is trained. Performance of these trained BP network in different case of test error is studied. The results show that adding a random error to the training samples can effectively improve the recognition ability of a BP network.

Abstract: In this paper we introduce sandbag cofferdam combined with sand-filling core of embankment ,integrate stability’s checking calculation using method of limit equilibrium, analysis and adjustment of parameters, comparing with finite element numerical simulation and other means, in order to analyze nearly horizontal plane landslide, summarize its genesis, deformation mechanism, and provide prevention basis for this kind of landslide.

Abstract: Based on seismic analysis of concrete-masonry mixed structure, a new strengthening method will be introduced. In order to find the effective and reasonable reinforcement measures to adjust to the characteristics of the mixed structure, the method of equivalent stiffness should apply to the structure, it can change the original unreasonable force transmission route, and then transform and reinforce the original structure into a quasi-frame-shear wall structure whose force transmission route is similar to frame-shear wall structure. This could be a reference to similar projects.

Abstract: Based on BOTDR distributed optical fiber sensing technology, this paper studies the variation law of branch pile axial force under the action of pile head loads and the action characteristic of pile side resistance during static load test. The result shows that: the branch of squeezed branch pile, as the major load-carrying object, bears most of the pile head loads and its function gradually emerges with increasing pile head loads. Under the action of pile head loads, the settlement and compression value of branch pile is elevated, which gradually brings about free face between branch and its overlaying soil layer. When the load exceed certain amount, the overlaying soil body of branch cracks under pile-soil interaction, and gradually loses its structural properties, because of which its settlement emerges and negative friction subsequently generated. Thus, during the design of branch pile, one should improve the properties of the soil layer around branch pile, enhance the strength of pile shaft, and lessen pile compressing deformation and settlement, so as to elevate the bearing capacity of branch pile.

Abstract: A new expert system was built for safety assessment of soft soil roadbed, in which the characteristics was taken into account by using Analytic Hierarchy Process (AHP) for identifying weight matrix of evaluating index, Fuzzy Synthetically Judgment for modeling safety evaluation of soft soil roadbed. The authors had attempted to develop the expert system to be comprehensive, concise, scientific, independent and flexible. Also, the system had been used to assess the safety of the Binhai highway of Tangshan, China. The results showed that the system is objective, feasible and practical, and can be used to assess the safety of soft soil roadbed.

Abstract: Due to the diversification of soft soil’s treatment methods in coastal region, the evaluation of the treatment‘s effect on freeway is the main basis of the acceptance check. According to some highway’s soft soil foundation’s treatment combined with data of ground settlement during construction, make science evaluation of the treatment effect on soft soil foundation.

Abstract: This paper is to study the seismic response of spatial structure incorporating the soil structure interaction (SSI). The SSI model for the long-span spatial structure with supporting substructure is proposed and the relevant soil parameters according to the IBC code are presented. A procedure for calculating the total damping ratios for one DOF system is used in the seismic analysis of spatial structure including SSI. The displacement and the axial force in the member under different soil conditions are compared and some important conclusions are drawn.

Abstract: Through the ABAQUS three dimensional modeling, established the dog-bone connection and traditional connection’s 3D finite element model, obtained the beam to column’s hysteretic curve, crack tip’s stress intensity factor as well as energy release rate at the weld of beam-column connection, the middle of reduced beam section and the same place in traditional connection. The theoretical analysis indicated, reduced beam connection’s hysteretic curve is more plumpness in shapes, have no significant pinch phenomenon, spindle shape, so the energy dissipation is better. From the view of fracture toughness, the weld joint’s fracture toughness is basically the same between dog-bone connection and traditional connection, the curves of weld crack tip’s biggest stress intensity factor as well as energy release rate about the two types connection are separately overlap, but at the middle of reduced beam section compared with the same place at the traditional connection, crack tip’s biggest stress intensity factor as well as energy release rate are significantly increased, when the initial crack length 3mm is assumed at the middle reduced beam section and the same place at the traditional connection, the reduced beam section connection’s nominal stress when reaching the material toughness KIC, it is 17% lower than traditional connection, in stress developing process, the middle of reduced beam section’s stress is biggest and it can reach material toughness. So the reduced beam connection can play a role as fuse, realize strong joints weak pole design concept.

Abstract: A brief introduction of Nanchang International Financial mansion manometry test model was stated first, And based on the Fluent software platforms, Wind pressure on the surface of high-rise building with the influence of adjacent buildings is simulated by computation fluid dynamics (CFD) methods. The results show that the numerical wind tunnel to some extent, more in line with the measurement results, but the errors in some parts are still large, relevant results will provide references for the research and the engineering practice.