Abstract:Tianjin Haihe Jizhao Bridge is a three-span continuous steel-concrete composite truss bridge with variable section. It is located in a high-intensity earthquake area with a peak acceleration of 0.15g. According to the structural characteristics of Jizhao Bridge, a new idea is put forward to design the mixed energy dissipation isolation system, which is composed of lead core isolation rubber bearing and mild steel energy dissipation barrier, which can improve the seismic performance of the structure and reduce the engineering cost. This paper mainly introduces the seismic design idea, seismic isolation design method and main technical content of Jizhao bridge.

Abstract:Taking the seismic design method of small and medium span beam Bridges as the research object, a systematic and comprehensive earthquake damage survey of small and medium span beam Bridges in Wenchuan area is carried out, the earthquake damage forms of beam Bridges are summarized, and the damage conditions of various components are analyzed by statistical analysis. It is proved that the beam Bridges in Wenchuan earthquake have more main beam displacement, more earthquake damage of supports and stoppers, less earthquake damage of piers, and main beam fall Less prominent features; By means of shaking table test and numerical simulation, the mechanism of earthquake damage of beam bridge is studied. The results show that the relative sliding between the main beam and the plate rubber bearing plays a seismic isolating role, reduces the seismic internal force response of the pier, and significantly reduces the earthquake damage of the pier. The bridge floor continuously coordinates the displacement of the main beam, and the abutment constrains the longitudinal displacement of the main beam, which is the main reason for the few falling beams in the Wenchuan earthquake. Based on the seismic damage analysis and mechanism research of small and medium span beam bridge, the seismic design concept of using the limited relative sliding between the main beam and the support to reduce the acceleration response of the superstructure and reduce the pier damage is proposed.

Abstract:Fully prefabricated bridge is a set of high efficiency, low carbon, environmental protection bridge construction technology, this paper will focus on the practice of this technology. Based on the development situation at home and abroad, the prefabrication and assembly technology of superstructure is briefly introduced. Then, the prefabrication technology of substructure is introduced, including the common joint method of prefabrication columns at home and abroad and the seismic performance of prefabrication columns. Finally, the full prefabrication technology is summarized.

Abstract:The 2008 Wenchuan earthquake in Sichuan Province greatly promoted the development of earthquake reduction and isolation technology in China. In China, various kinds of vibration isolation devices used in bridge vibration isolation design technology have also been introduced. Among them, the lead core isolation rubber bearing is one of the most widely used isolation devices. Due to the vast area of China, the local environment and climate are very different, its minimum temperature from 0 ° C to -40 ° C are not the same, how is the low temperature performance of lead rubber bearing, whether it is suitable for use in various regions of China, is the content of this paper to discuss.

Abstract:On the basis of summarizing the experience of bridge expansion devices at home and abroad, this paper discusses the basic performance requirements, main types, running performance requirements, design calculation rules, seismic design and performance detection of highway bridge expansion devices, which can be used as reference for engineering and technical personnel.

Abstract:Taking the Luding Dadu River Bridge of Yakang Expressway as the research background, the spatial dynamic calculation model of the bridge is established, and the influence of rigid central buckle, flexible central buckle and energy-consuming central buckle on the seismic performance of the structure is studied by using nonlinear time-history analysis method. The energy dissipation central buckle is the first time to apply the anti-buckling energy dissipation steel supporting member to the suspension bridge, using the good hysteretic energy dissipation performance of steel to consume the seismic input energy and protect the main structure of the bridge from damage. The results show that the comprehensive performance of energy-dissipating central buckle is much better than that of traditional rigid central buckle and flexible central buckle, and it is an ideal central buckle suitable for large-span suspension Bridges in high-intensity earthquake area.

Abstract:In recent years, with the increasing application of vibration reduction and isolation technology in Bridges, liquid viscous dampers, as an important device of vibration reduction and isolation measures, have been applied more and more in bridge engineering, especially in special long-span Bridges. There are a large number of domestic and foreign manufacturers of dampers, and the levels are not uniform. There is no mature system to follow for the quality detection of dampers in our country. Based on the advanced American AASHTO for locking devices and the European code EN15129 for velocity dampers, this paper discusses the relevant regulations and testing methods of liquid viscous dampers used in Bridges, which can provide reference for the quality control of dampers used in bridge design.