振动台试验是高层及复杂结构抗震性能研究的一种重要手段.微粒混凝土是振动台试验模型中用来模拟混凝土的一种基本材料,其性能直接影响振动台试验结果的准确性.本文通过17组不同配比微粒混凝土试块的力学性能试验,研究了水灰比、灰砂比、砂的级配、外加剂等因素对其力学性能关键指标(弹性模量、抗压强度)的影响,并结合试验结果提出了调整配比的方法,研究结果可为振动台试验模型用微粒混凝土的试配提供指导.

叠层橡胶支座是隔震技术关键因素之一,研发了一种串联型变刚度叠层橡胶隔震支座.该串联型变刚度叠层橡胶隔震支座初始阶段提供较小水平刚度(小于串联型变刚度叠层橡胶隔震支座中较小直径支座的刚度).当水平剪切变形达到设计目标时,通过限位装置提供第二刚度,使其出现较大变形时具有较大的大水平刚度.通过足尺支座试验,研究了该串联型变刚度支座的竖向性能、水平性能和滞回性能,并给出了该串联型变刚度支座的计算模型.

《建筑抗震鉴定标准》(GB 50023-2009)提出,A类钢筋混凝土房屋可按楼层综合抗震能力指数法和构件承载力计算法两种方法进行结构抗震鉴定计算.结合工程实例,采取两种方法进行工程抗震鉴定对比计算分析.研究结果表明,构件抗震承载力计算法较楼层综合抗震能力指数法得到的评定结论更为可靠,更能有效保证结构的安全性能,可为该建筑后期加固改造和使用提供更严格的鉴定结论.建议A类既有建筑结构的抗震鉴定计算以构件承载力验算为主,楼层综合能力指数法为辅.

武汉绿地中心副楼裙房4层钢平台位于中庭位置,因部分钢平台构件超重,现有塔式起重机无法吊装就位.经过方案对比分析,选用胎架支撑+汽车式起重机上楼板高空原位拼装施工方法.首先根据钢平台构件分段位置及首层楼板混凝土梁位置,合理布置支撑胎架,然后采用25t汽车式起重机上首层楼板进行高空原位拼装.考虑胎架布置紧凑及受周围土建结构影响中庭位置空间狭窄等因素,将胎架及时卸载周转,为汽车式起重机站位及行走让出道路,同时也减少胎架投入,降低施工成本.通过系列技术措施,有效解决了在结构内部进行超重钢结构施工的技术难题.

Laminated rubber bearing is one of the key factors of seismic isolation technology, the research group developed a parallel-connected laminated rubber bearing which has friction energy dissipation characteristic and can change the stiffness.The parallel-connected seismic isolation was composed of inner isolation, outer ring friction plate and outer ring isolation, when the horizontal displacement of the combined bearing was small, the horizontal stiffness and the horizontal restoring force were provided by the small bearing of the inner ring.The outer ring friction plate provided the friction and the outer ring bearing was free to slide.When the bearing was horizontally deformed to the target, the horizontal stiffness was provided by the inner ring bearing and outer ring bearing, and the horizontal stiffness was significantly improved, the friction plate was in a stationary state.Full-scale tests were conducted to study the vertical properties, horizontal properties and hysteretic behavior of the variable stiffness bearings.The experiment results showed that, during the whole experimental process, the inner ring bearing and outer ring bearing could share the vertical load.

A kind of metal energy dissipation damper applied to frame structure which has large deformation was introduced.The test results showed that the JY-USD damper with deformation of 10,20,40 mm could keep a stable hysteretic behavior when they were repeatedly loaded for 3 times, so did the damper with deformation of 60 mm when it was repeatedly loaded for 30 times, and the dampers were not damaged.This kind of damper was applied in a frame, and it could provid a 1.8% additional damping ratio for the structure under frequent earthquake.The deformation of the structure could meet the requirements of the design code under rare earthquake, and the hysteresis curve of the damper was full.The proposed energy dissipation and shock absorption scheme should be recommended.

Cantilever truss was often adopted for super high-rise structure with the strengthening layer.Because of the stable tension and compression performance,unbonded braces were widely accepted in projects to replace the ordinary steel supports to increase structure seismic performance.Nonlinear time-history analysis method by software ABAQUS was used to analyze the seismic performance of structure with unbonded braces or ordinary steel supports under the rare earthquake,including the deformation,member force and shear wall damage etc.The results show that compared with the ordinary steel supports,the unbonded braces have good seismic performance,and the stiffness and strength can be easily controlled.Hysteretic behaviors are stable under large deformation,and can absorb the seismic energy firstly under the rare earthquake.

According to the situation that Chinese Earthquake Resistant Design Code(GB50011-2010) does not rule the expression of vertical acceleration response spectrum,this paper collected hundreds of strong earthquake records in United States to study the influence of the factors such as seismic environment and structure damping ratio on the spectral ratio(V/H).The authors selects some influencing factors which has a great impact on the spectral ratios and the regularity is good,including site conditions,epicentral distance and structural damping ratio.Based on genetic algorithm(GA) programming,the global optimum fitting results were researched.The fitted spectral ratio with impact of site condition as the datum spectral ratio is taken.Simultaneously,the impact of epicentral distance and damping ratio,was carried on the revision to the datum spectral ratio,thus the suggestion type of the spectral ratio under various earthquakes environment was established.Finally,the horizontal acceleration design response spectra was stipulated by current seismic design code of China and multiplied by the suggestion type of the spectral ratio from corresponding earthquake environment,then the suggestion type of the vertical acceleration design response spectra from this earthquake environment is obtained.

Since the government raised the earthquake seismic f or tification level of schools,most of primary and middle schools in the country n eed seismic strenthening.Buckling restrained braces is a special center support,it's a combination of the central support and the metal yield damper.It can b e used for steel designing,reinforced concrete structural designing,seismic st rengthening of reinforced concrete frame and so on.Buckling restrained braces h ave a more full hysteresis curve compare with ordinary braces and it will be yie ld by compression and tension.At the same time,the technology is simple and fe asible.Using the buckling restrained braces in the field of seismic strenthening can greatly shor ten the construction period,reducing the workload of reinforcement,saving cost s of re-decoration.

Great earthquake happened frequently worldwide in recent years.So Chinese seism ic code was amended,which enhance the performance of the design requirements.T he energy dissipation control theory is one of the core of the problem.Some cou ntries with frequent earthquake occurrence view mild steel damper as the main me ans of energy dissipation because of its superior performance,strong energy dis sipation capacity,easy to use and other advantages.But the domestic engineerin gs can't bear the high price of foreign products.Therefore,Chinese Academy of Building Research has developed a type of JY-SS Metal Shear Damper which accord ing with Chinese conditions basing on the existing experience.JY-SS Metal Shea r Damper was proved to be perform steady through a arge number of experimental r esearch and theoretical analysis,it has been applied in practical projects beca use of it's high performance-price ratio.

Division and multi-step unloading is adopted in large-span steel roof structure in Shenzhen Bay Sports Center.The structure is divided into 34 sections,the safety of unloading,selection of jack type and estimation of unloading displacement need pre-analysis.Because of geometrically nonlinear influence,there are must be the difference between multi-stage forming structure and design shape.Authors suggest that if making the stressing state of unloading structure as initial state in structure design,with secondary checking calculation combined with other conditions,the construction degree of freedom should be improved.

In order to analyze the seismic behavior of exterior beam to column joints of large multi-story precast concrete structures,an experimental study on full-scale beam to column joint models subjected to high axial loading and reversed cyclic loading was conducted.The failure pattern,hysteretic characteristic,skeleton curve,displacement ductility and energy dissipation were analyzed.The numerical joint model taking the rebar slippage into consideration was developed based on the OPENSEES software and validated against the experimental results.Then the parametric analysis was performed.The study results indicate that the overall seismic performance of the precast joint is almost the same as that of a monolithic joint.Column section dimension has a greater impact on the capacity of joint than the loading level of the column,rebar diameter has an impact on the unloading stiffness and pinching behavior,instead of on the capacity of joint.

Chinese standard Earthquake Resistant Design Code(GB50011-2010) stipulates that the vertical earthquake peak effect coefficient is taken as 0.65 times of the corresponding value on the horizontal direction.This article presents three components of strong earthquake data 292 groups,584 items from the Midwest of the USA.The data were used to research the structural damping ratio and influence on the ratios(V/H) of vertical response spectra V to horizontal response spectra H.The change pattern of the curves V/H with impacting of respective factor was analyzed.The magnitude of the epicenter,site,category and the influence of the damping factor on the spectrum V/H were studied.The influence of magnitude,the epicenter,site category and damping factor for the average spectrum ratio curve shape were studied and were then compared to the value 0.65 specified in the standard.It is suggested that various factors influencing the ratio of advice type should be taken account in determining spectrum.The paper demonstrates the usability of the collected strong earthquake data and the credibility of the research results.

The bearing capacity analysis of iced transmission tower structure is important both in theory and engineering practice.This study takes 500 kV cup type beeline tower as an example to establish the spatial finite model of the tower,which is used for structure analysis under the dead load,ice load,wind load and conductor tension.The stress,strain,and displacement are obtained by analyzing the model under combinations of 18 kinds of loads.Finally,the most unfavorable working position of the transmission tower are found out based on the result of calculating.Optimizing design is undertaken by setting up supports at cross-arm and tower body and changing the form of tower neck.The calculation proved that the stiffness and capacity of the transmission tower has improved greatly.

In order to analyze the seismic behavior of multi-story precast concrete structures,experimental study was conducted for some typical joints of an apartment building.With full-scale models,the seismic behavior of precast layered slab and beam to column exterior joints was investigated under high axial loading and low-cycle reversed loading.The failure pattern,hysteretic characteristics,skeleton curve,ductility,energy dissipation and abutted seam,were analyzed.The results indicated that the earthquake resistance performance of this type of connection is almost equal to that of monolithic connections.

Basing on environmental monitoring origin and appraisal development process,this paper mainly introduced the application of 3S technology,biological technology,information technology and the monitoring methods of physical chemistry science in environmental monitoring technology in the view of the scientific nature of monitoring result,the systematic characteristic of monitoring method and the emergency technical usability. Mean times,according to the characteristic of environmental question in China,the development trends of environmental monitoring technology were also discussed.

In this paper,taking the construction of the cantilever scaffold with steel wire rope unloading in Kaiheng Center as example,the ways of constructing scaffold and joint treatments by anchoring with ring and drawing steel wire with I type steel are introduced on emphases according to structural design characteristics.

This article introduces the philosophy for the design, the construction method and the technics in hoisting steel spatial grid roofstructure for China Disabled Physical Training Centre. In this project, the con- struction technic of hoisting whole button pole group is being applied. In other words, this method is firstly assembling the whole structure on the ground, then hoisting with button pole group, finally put the structure into the position with excursion in the air.

Qujiang Commercial Club Building in Xi'an is a multifunctional one that consists of the functions of restaurant, hotel, shopping, bank, recreation site and meeting centre etc. It is unique in shape.It is mainly introduced the selection of structure system, the control of elastic drift between storey, the design gist of column and beam connections, which is analyzed according to construction conditions.

该商务会所集餐饮、宾馆、购物、银行、休闲、会议等功能于一体,建筑造型独特,空间要求较高,主要介绍了结构体系的选择,结构弹性层间位移角的控制、楼盖设计、梁柱连接节点、柱脚等设计要领,并结合施工实际对设计进行了分析和总结,可供设计者参考.