Abstract: In order to improve the effect of isolation structure, the principles and behaviours of the base-isolation system are studied, and the types and characteristics of the base-isolation are also discussed. Compared to the traditional aseismatic structures, the base isolation structures decrease the seismic response obviously: the total structural aseismatic value decrease 1/4-1/32, the seismic shear stress in the upper structure decrease 1/14-1/23. In the huge seism, the structure can have the obvious aseismatic effect.
Abstract: Based on the methods of qualitative and quantitative, the engineering geological characteristics of one high cut slope in Wanzhou region of Chongqing is evaluated. The results are obtained: (1) the stratum composed of the high cut slope from top to bottom are artificial accumulation including gravel soils, residual silty clay, silty mudstone; (2) the main weak planes include the interface between soil and rock, two group joints and fissures in the bedrock and bedding plane in the high cut slope; (3) based on the results of stability evaluation, it’s in stable condition at present, but has dropped stone and collapse phenomenon. In the long term effect of weathering and groundwater, the overlying soil creeping deformation along the flare mudstone level would occur.
Abstract: As an important structural member in Chinese timber structure system, Dougong has an excellent capability in earthquake resistance. Through low cyclic loading experiment of single Dougong, two Dougongs and four Dougongs, the degrading rule of lateral stiffness of Dougong was studied. According to that, the hysteresis curve and skeleton curve of force –displacement were researched and the formula of resilience model and mechanical model were established. The experiment data show that slippage is the main deformation of Dougong. Energy dissipation due to frictional slippage is an important reason for the excellent seismic behavior of ancient wooden structure. The shape of hysteretic loops of Dougong assumes to be parallelogram. Plump area of hysteretic loop accounts for its excellent energy dissipation performance. The mechanic model of Dougong belongs to linear strengthen elastic-plastic model. Both the fitting equation of force-displacement and resilience model reflect stiffness changes of Dougong. These basic theories provide a theoretical basis for the study on the seismic performance, repair and strengthening of ancient wooden structures.
Abstract: The effect of moisture content on the density and the strength of cement-solidified sea silt road embankment adding phosphate tailing was investigated. The optimum solidifying time was determined based on uniform experimental design method considering the factors of cement content and phosphate tailing content at 5 design levels. The different mix proportions were defined. Utilizing compaction test and unconfined compression strength test, referencing to the fluidity experiment of cement concrete, the optimum moisture content is studied on the basis of theories and tests. The influence factors about the optimum moisture content are discussed.
Abstract: Debris flow is one of the usual mountain geological disasters, and it is significant to assess and forecast its risk degree. The paper bases on statistical analysis of influence factors of debris flow risk degree, establishing 15 indexes to accurately assess debris flow risk degree. Furthermore, the evaluation index system is constructed by using analytic hierarchy process. And after combining the linkages between indexes, calculating each weight, and amending repeatedly with examples, finally the comprehensive mathematical evaluation on risk of debris flow is set up.
Abstract: In order to study the causes of freezing injury of railway subgrade and find out the effective method to solve this problem, so that the safety and comfort can be guaranteed through traveling. The author analyzes the reasons that cause the freezing injury of railway subgrade and propose injecting salt method to solve this problem through the experiments study on the frozen soil of railway subgrade at Jilin section of Beijing-Harbin line.
Abstract: In order to analyze load bearing capacity of column with different steel tube diameters under horizontal displacement, and provide reference for further study about seismic performance of column which is called CFRP steel reinforced concrete filled with steel tube concrete column, this paper makes the nonlinear finite element analysis on this column by using ABAQUS. The load–displacement curves of the specimens with different steel tube diameters are acquired by establishing model, choosing constitutive relationship, making unit types and mesh settings, and then analyze the influence of different steel tube diameters on load bearing capacity of specimens. The curves show that with the increasing of steel tube diameters, the slope of curves in the elastic stage increases, besides, maximum point of load–displacement curves in the elastic stage is increasing. The results show that only with horizontal displacement, the slope of curves and the bearing capacity in the elastic stage is increasing with the increasing of diameters, it is clearer when the horizontal displacement is small.
Abstract: Based on the damage field survey of the industrial building in Wenchuan earthquake, the typical building seismic damage characteristics of industrial structures were summarized and analyzed. According to the damage phenomenon, the following conclusions are derived: usually, the main structures of industrial buildings received serious damage, which roof system were distorted and collapse, bent-frame column were pressed and yielded, bracing system were tension broken or pressed and yielded; when the main structures of industrial building received minor damage, the non-structural member regular suffered relatively damage, include the end bays in the longitudinal direction, high gables, the cantilevered walls between two span with different height and the foundation. Then damage rules and reasons are summed up and damage characteristics and the corresponding design and retrofitting suggestion are proposed. At the end of the paper, it was indicated that seismic design of major structure and non-structural members of factory building must be fully complied with the Seismic Design Code, seismic assessment and seismic strengthening should be carried out at regular intervals for the existed industrial building, which served a long time and whose fortification level is unsatisfied with requirement.
Abstract: In this paper, the elasto-plastic dynamic analysis on the steel spatial arch truss with 60 m span and 0.4 rise-span ratio is carried out under earthquake wave with SAP2000. In the analyses, the geometric and material nonlinear effects are considered at the same time based on the plastic-hinge theory. Under the action of EL wave with the peak increasing gradually, its elasto-plastic dynamic responses have been obtained. The results show that its failure mode under the earthquake action is elasto-plastic dynamic buckling; that its critical peak acceleration of EL earthquake wave when applied in horizontal direction is 808.5 gal, and is 789.0 gal when applied in vertical direction; The ratio of its maximal node horizontal displacement and its structural height is 1/259, and its displacement ductility coefficient is 1.071; The ratio of its maximal node vertical displacement and its structural span is 1/736, and its displacement ductility coefficient is 1.105.
Abstract: Based on the analysis of the economic evaluation of green building, taking references of 《Evaluation standards of green building》 (GB / T 50378-2006), indicators reflecting the economy of green building are selected through expert scoring method and fuzzy statistics method .Furthermore, a comprehensive evaluation model is established based on principle of fuzzy mathematics through the application of AHP aiming at determining the index weight. All above is to provide a wider perspective for the economic evaluation of green building.