Applied Mechanics and Materials Vols. 638-640

Abstract: Structure Collapse failure is the main reason leading to casualties and property damage when an earthquake occurs. In this article, the masonry structure with prefabricated slab is as the object of study. The damage reason and shortcoming of masonry structure during earthquake are in deep analysis through the structural defect, design reinforcement, engineering quality and other aspects. A new type anti-seismic prefabricated slab is designed aiming at the defects of traditional one. Prefabricated slab vertical and horizontal connections were set closed. The joint bars in these two directions were respectively used to connect prefabricated slabs. All the floor slabs were joined to form a whole after the concrete pouring around the plates, which enhanced the floor stiffness and integrity. So the purpose for ultimately improving the anti-seismic performance of masonry structure purposes was accomplished. The comparative analysis of numerical simulation for masonry structure also shows that the overall seismic behavior of the structure has been greatly improved due to the increasing in prefabricated vertical and horizontal joint elements.

Abstract: Series isolation system consists of rubber isolation bearings and composite disk springs, determination method of vertical stiffness and vertical damping of isolation layer is given. Entering the near-fault vertical seismic waves, the affect of isolation layer parameters and earthquake intensity on the isolation effect is studied. Studies have shown that the vertical isolation effect increases with the increase of vertical damping ratio. When the damping ratio reaches a certain value, the isolated effect leveles off. When calculating model is adopted as the hierarchical model, vertical isolation effect has nothing to do with the increases of earthquake intensity.

Abstract: A series of light-weight column for receiving the wireless signals to control the stoppage of gas supply are built on the liquefiable ground and their seismic stability should be precisely investigated to prevent the second accident. For the conventional judgment of liquefiable ground, if the soil type of the ground surface is the same, the potential liquefaction of the ground is also the same. In this paper, based on the soil-water coupled finite element method the influence of the depth of the liquefiable layer is taken into consideration and it is found that the seismic stability of the column varies significantly depending on the depth of liquefiable layer even though the embedment depth of the column is the same. Therefore, it is necessary to con-sider the depth of liquefiable layer for the high accuracy analysis.

Abstract: With the rapid development of underground space exploration in Chinese cities, the construction scale of underground subway structures expands continuously. This thesis elaborates the development history of seismic research on underground subway structures, summaries the seismic response characteristics of the structures, and analyzes the seismic research methods of underground subway structures including the prototype observation, theoretical analysis, numerical simulation and experimental research and discusses the characteristics and usages of each research method. At last, several important problems have been proposed for seismic research and seismic design of underground subway structures in China.

Abstract: The uniaxial cyclic fatigue tests on granite coming from the ChangJiang of Hainan nuclear power first-stage construction conventional island were done on the RMT-150B multi-function automatic rigid rock servo material testing machine. Stress amplitude of 10 MPa and sine wave cyclic loads with five different frequencies of 0.01, 0.02, 0.05, 0.1, 0.2, 0.5, and 1 Hz were adopted as dynamic disturbance. The law between cyclic frequency and dynamic stress-dynamic strain hysteretic curve, dynamic elastic modulus and damping ratio are researched. The results showed that the curves of strain and stress for loading and unloading are not superposition under cyclic loading, but hysteretic loops. When cyclic frequency changes between 0.01 and 1.0 Hz, the granite hysteretic loop area, dynamic elastic modulus and damping ratio are increased with frequency increasing. The research result offered great reference value to seismic response analysis and site safety evaluation of the changjiang nuclear power.

Abstract: Ancient architecture in Europe is one of the most historic and characteristic system in the world. It follows the order of combining structure and aesthetics. Researching in the pendentive used in Hagia Sophia, this paper explores that European ancient architecture is harmonious and unified in both structure and aesthetics.

Abstract: The construction of large-span structures has been continuously increasing domestically since 2005, but despite this trend, there are no existing fire prevention regulations and building standards for large-span structures. Accordingly, as a basic research for coming up with evacuation safety techniques for large-span structures, this study sought to derive the evacuation characteristics of building occupants in case of a fire in large-span structures by formulating the definition of large-span structure and analyzing fire cases in spatial buildings at home and abroad. It is expected that the findings of this study will be utilized as basic materials for fire scenarios that consider fire scenario application criteria (human security standards, capacity calculation standards) as well as multiple risk factors such as frequency, probability, and combustion expansion and spread based on the evacuation characteristics derived from this study.

Abstract: Terrorist attack is a great threat to the safety of the city. Due to particularity of the subway tunnel, the concrete lining will produce the strongly nonlinear response and dynamic damage under blast load, even collapse of the concrete lining structure. Protection technology of the concrete lining under blast load has become an urgent problem to be solved. By the means of the finite element software, this essay simulates the highly nonlinear response of concrete lining with aluminum foam. Aluminum foam has been widely used in the field of disaster preventive and mitigation. Application of the aluminum foam under blast load can absorb a large amount of impact energy and reduce the peak value of pressure in the concrete lining.

Abstract: Based on the features of fire and explosion accidents in petrochemical wharf storage tank area, the DOW method and fuzzy comprehensive evaluation method were applied to evaluate risk of fire and explosion. First of all, DOW method was employed to evaluate the hazard of fire and explosion of petrochemical wharf storage tank area preliminarily and risk indexes of various tanks were obtained. Then, 5 first-level and 24 second-level indexes were identified by the fuzzy mathematics, in which the entropy weight method was introduced to determine weight vector of arrangement analysis, and applied to an actual risk evaluation for a petrochemical wharf storage tank area to determine fuzzy sets. On the basis of the weighted average method, the risk level is medium. Arranges the second-level indexes, and the main factors affecting the accident were concluded,including the violation rate of labor discipline, characteristics of hazardous materials, fire facilities, safety checks, operation of the security emergency response system and so on.

Abstract: This article through to in the process of MTBE production major hazards identification, what is the major hazards in the production process are put forward in this paper, determine the theory and method of major hazards, calculate and determine the critical mass of major hazards, identify the risk level.