立式钢制储罐基于地震损伤性能的抗震设计方法

针对立式钢制储罐在强烈地震作用下会产生不同程度的损伤的特点，遵循抗震设计规范的“小震不坏，中震可修，大震不倒”的抗震设计原则，结合三水准烈度，提出了储罐的地震损伤性能目标，并给出了基于地震损伤性能的抗震设计方法。所提出抗震设计方法，更加准确地考虑了储罐的提离问题。     

基于推覆分析的钢框架结构地震倒塌判别准则研究

结构地震倒塌判别准则是工程结构强震分析的关键问题。在层损伤模型的基础上,建立了基于推覆分析的建筑结构整体损伤模型,并以国内某2层2跨平面钢框架结构拟静力试验为背景,应用有限元程序ABAQUS对平面钢框架进行了强震倒塌数值模拟。分析了钢框架结构的倒塌破坏过程,基于建议地震倒塌判别准则研究了钢框架结构的损伤演化规律。结果表明:钢框架结构在强震作用下的损伤发展顺序与塑性发展顺序一致;基于推覆分析的结构整体损伤模型能较好的体现强震作用下钢框架结构的损伤演化规律,且在上下界处收敛;强震作用下,钢框架结构的初始损伤主要由结构的残余侧移引起,而后期损伤主要由结构的承载力和刚度退化引起。     

强震下拱式体系桥梁震害特征及抗震研究

以汶川地震中拱式体系桥梁震害为主线,总结主拱圈、横向连接系和其它附属构件及减隔震设计拱桥的破坏情况,对国内外拱桥的震害特征及原因进行了剖析。以目前应用数量占优的钢管混凝土肋拱桥为具体背景,对拱式体系桥梁的抗震理论、抗震试验和减隔震设计进行了评述。分析认为拱式体系桥梁竖向和纵桥向抗震存在一定的安全储备,但横桥向存在明显的抗震薄弱环节。针对钢管混凝土肋拱桥横桥向振动及倒塌特点,就目前在拱式体系桥梁中引入防屈曲支撑代替横撑以形成耗能减震结构提出了建议及具体可行设计方式。     

Development of fragility functions as a damage classification/prediction method for steel moment‐resisting frames using a wavelet‐based damage sensitive feature

Fragility functions are commonly used in performance‐based earthquake engineering for predicting the damage state of a structure subjected to an earthquake. This process often involves estimating the structural damage as a function of structural response, such as the story drift ratio and the peak floor absolute acceleration. In this paper, a new framework is proposed to develop fragility functions to be used as a damage classification/prediction method for steel structures based on a wavelet‐based damage sensitive feature (DSF). DSFs are often used in structural health monitoring as an indicator of the damage state of the structure, and they are easily estimated from recorded structural responses. The proposed framework for damage classification of steel structures subjected to earthquakes is demonstrated and validated with a set of numerically simulated data for a four‐story steel moment‐resisting frame designed based on current seismic provisions. It is shown that the damage state of the frame is predicted with less variance using the fragility functions derived from the wavelet‐based DSF than it is with fragility functions derived from an alternate acceleration‐based measure, the spectral acceleration at the first mode period of the structure. Therefore, the fragility functions derived from the wavelet‐based DSF can be used as a probabilistic damage classification model in the field of structural health monitoring and an alternative damage prediction model in the field of performance‐based earthquake engineering. Copyright © 2011 John Wiley & Sons, Ltd.     

多龄期钢框架结构地震损伤模型研究

基于ABAQUS非线性有限元分析,通过控制变量法分析得出影响多龄期钢框架地震损伤的主控因素为构件有效截面收缩与钢材极限强度退化。定义广义的锈蚀损伤,并探索锈蚀损伤与未锈蚀原型结构地震损伤的关系,最后建立基于未锈蚀原型结构地震损伤的多龄期结构地震损伤模型。     

考虑锈蚀的钢框架柱地震损伤模型研究

为准确评估锈蚀钢框架在地震作用下的损伤,对已有的地震损伤模型进行改进,并对框架柱的地震损伤特性进行分析。建立基于变形和能量组合的双参数损伤模型,对损伤模型中相应的参数给出具体定义和表达式,定义不同破坏等级的损伤指数范围。对3个具有不同锈蚀率的空间钢框架结构进行弹塑性时程分析,并对损伤模型的准确性进行验证。研究结果表明,该模型能够较好地描述锈蚀钢框架柱的地震损伤程度。研究结果可为该类结构构件的地震损伤评估以及基于损伤的抗震设计方法的建立提供理论依据。     

Preliminary investigation of seismic damage to two steel space structures during the 2013 Lushan earthquake

Severe damage to steel space structures is rarely reported when compared to other structural systems damaged during past major earthquakes around the world.Two gymnasiums of steel space structures in downtown Lushan County that were damaged during the 2013 M7.0 Lushan earthquake in China were investigated and the observations are summarized in this paper.Typical damage to these two steel space structures ranges from moderate to severe.Moderate damage includes global buckling and dislocation of bolted connections of truss members,and inelastic elongation of anchor bolts and sliding of pedestal plates of supports.Severe damage includes member fracture caused by local buckling,and fracture failure of anchor bolts and welds.The distribution of structural damage to these two structures is described in detail and future research opportunities are suggested.     

Tsunami damage to coastal defences and buildings in the March 11th 2011 M w 9.0 Great East Japan earthquake and tsunami

On March 11th 2011 a M _w 9.0 mega-thrust interface subduction earthquake, the Great East Japan Earthquake, occurred 130 km off the northeast coast of Japan in the Pacific Ocean at the Japan Trench, triggering tsunami which caused damage along 600 km of coastline. Observations of damage to buildings (including vertical evacuation facilities) and coastal defences in Tōhoku are presented following investigation by the Earthquake Engineering Field Investigation Team (EEFIT) at 10 locations in Iwate and Miyagi Prefectures. Observations are presented in the context of the coastal setting and tsunami characteristics experienced at each location. Damage surveys were carried out in Kamaishi City and Kesennuma City using a damage scale for reinforced concrete (RC), timber and steel frame buildings adapted from an earlier EEFIT tsunami damage scale. Observations show that many sea walls and breakwaters were overtopped, overturned, or broken up, but provided some degree of protection. We show the extreme variability of damage in a local area due to inundation depth, flow direction, velocity variations and sheltering. Survival of many RC shear wall structures shows their high potential to withstand local earthquake and significant tsunami inundation but further research is required into mitigation of scour, liquefaction, debris impact, and the prevention of overturning failure. Damage to steel and timber buildings are also discussed. These observations are intended to contribute to mitigation of future earthquake and tsunami damage by highlighting the key features which influence damage level and local variability of damage sustained by urban coastal infrastructure when subjected to extreme tsunami inundation depths.     

矩形钢筋混凝土蓄水池震害预测方法及分析程序简介

本给出了一种矩形有疬钢筋混凝土蓄水池的震害预测方法和计算分析程序，并对两蓄水池进行了震害预测分析，得出震害经验相符合的结论－地下式水池比地上水池的抗震能力强，从而证明了本方法的实用性。     

高层钢结构基于均匀损伤设计的整体抗震能力提高方法

本文主要研究如何通过合理设计来提高高层钢结构的整体抗震能力。首先,给出了高层钢结构的非线性计算模型;其次,建立了高层钢结构在强地震动作用下的倒塌失效模式的极限状态判别准则;然后,通过模态pushover分析,研究了高层钢结构在水平地震作用下的损伤规律;最后,重点研究了高层钢结构的整体抗震能力的提高方法,提出了均匀损伤的设计方法,该方法通过消除结构的薄弱层,来达到提高高层钢结构的整体抗震能力的目的。通过对两栋20层的高层钢框架结构进行极限时程分析和极限pushover分析,验证了文中提出的均匀损伤的设计方法的可行性。本文的工作可为高层钢结构的抗地震倒塌设计提供参考依据。     

抚顺钢厂场地震害效应预测

场地震害预测需要考虑区域地震地质背景和具体的场地条件本史分析了抚顺钢厂场地对震害有影响的各个因素,并利用模糊数学的方法划分出强、中、弱三种场地类型.研究结果表明.钢厂的场地大部分是好的和比较好的.     

高层钢框架-混凝土核心筒混合结构振动台试验研究

为了研究高层钢框架-混凝土核心筒混合结构的整体抗震性能,本文设计了一个典型的比例为1/15的20层钢框架-混凝土核心筒混合结构的缩尺模型,在同济大学土木工程防灾国家重点实验室实施了模拟地震振动台试验。本文重点介绍试验中模型结构在各级水准地震作用下的动力特性、加速度和位移反应,描述了模型结构的破坏位置及过程,并根据相似理论得到了原型结构的地震反应。试验研究表明:原型结构基本能够满足我国现行规范"小震不坏、大震不倒"的抗震设防标准;核心筒发挥了主要抗侧力作用;结构在大震作用下有较好的延性;钢框架与核心筒的连接节点在结构设计时应给予重视。     

DAMAGE STATISTICS OF 12 OCTOBER 1992 EARTHQUAKE IN THE GREATER CAIRO AREA

The paper describes the damage statistics of the 12 October 1992 earthquake (Dahshur earthquake) that hit the greater Cairo area in Egypt and measured 5.4 on the Richter scale. Building sample consisted of 2270 buildings distributed in almost every district in the greater Cairo area and their characteristics cover a wide range of date of construction and structural systems. Structural and non-structural damage to buildings are presented as functions of date of construction, height and type of construction. It is believed that the information presented in the paper is of extreme importance to the engineering community as to the structural impact that the 1992 earthquake had on building stocks in the urban area. © 1997 by John Wiley & Sons, Ltd.     

Coseismic surface rupture characteristics and earthquake damage analysis of the eastern end of the 2021 MS 7.4 Madoi (Qinghai) earthquake

At 02:04 on May 22, 2021, an M_S 7.4 earthquake occurred in Madoi County in Qinghai Province, China. This earthquake is the largest seismic event in China since the 2008 M_S 8.0 Wenchuan earthquake. Thus, it is critical to investigate surface deformation and damage in time to accurately understand the seismogenic structure of the Madoi earthquake and the seismogenic capacity of the blocks in this region. This study focuses on the Xuema Village, located at the eastern end of the coseismic surface ruptures produced by the event, and assesses the deformation and seismic damage in this area based on field surveys, UAV photogrammetry, and ground penetrating radar (GPR). The results indicate that the rupture scale is substantially smaller at the eastern end of the rupture zone compared to other segments. En echelon type shear tensile fractures are concentrated in a width range of 50–100 m, and the width of single fractures ranges from 20 to 30 cm. In contrast, the degree of seismic damage significantly increases at this site. All of the brick and timber houses are damaged or collapsed, while the steel frame structures and the color steel houses are slightly damaged. More than 80% of the bridge decks on the Changma River Bridge collapse, similar to the terraces along the Youerqu and Changma Rivers and the cut slopes of Provincial Highway S205. We infer that the seismogenic fault of the Madoi earthquake exerts a tail effect in this segment. The tension zone has led to a reduction at the eastern end of the rupture zone, causing shaking damage. Local topography and buildings without earthquake-resistant construction along the strike of the rupture zone have undergone different levels of seismic damage.     

震后企业停产减产损失估计方法的研究

企业停产减产损失是地震间接损失的重要组成部分，本文根据唐山地震的震害资料，提出了地震破坏后一个地区或城市因停产和减产而造成的经济损失的一个估计方法，为估计地城的时间损失提供了一个可行的途径，此法广泛适用于震后经济损失估计和震害预测工作。     

Observations and implications of damage from the magnitude Mw 6.3 Christchurch, New Zealand earthquake of 22 February 2011

This paper describes the observations made by a reconnaissance team following the 22nd February 2011, M_w 6.3, Christchurch, New Zealand earthquake (GNS Science, 2011). The team comprised of members of the UK based Earthquake Engineering Field Investigation Team who spent 5 days collecting observations on damage resulting from the earthquake. Although the magnitude of this earthquake was not particularly high (M_w 6.3), the shallow focus and close proximity resulted in locally very high ground motions, widespread damage and 182 fatalities. The earthquake is also particularly notable for the widespread liquefaction it caused, landslides and rockfalls in the hills south of Christchurch, and the significant damage suffered by unreinforced masonry and historic structures. Over wide areas of central Christchurch, recorded accelerations were in excess of those required by the current New Zealand seismic loadings standard (NZS1170.5:2004: Standards New Zealand 2004) and therefore the earthquake presented a valuable opportunity to assess performance of modern buildings under code-level ground acceleration.     

Seismic design, modelling and assessment of self-centering steel frames using post-tensioned connections with web hourglass shape pins

A new self-centering steel post-tensioned connection using web hourglass shape pins (WHPs) has been recently developed and experimentally validated. The connection isolates inelastic deformations in WHPs, avoids damage in other connection parts as well as in beams and columns, and eliminates residual drifts. WHPs do not interfere with the composite slab and can be very easily replaced without bolting or welding, and so, the connection enables non-disruptive repair and rapid return to building occupancy in the aftermath of a strong earthquake. This paper presents a simplified nonlinear model for the connection and the associated beams and columns that consists of nonlinear beam-column elements, and hysteretic and contact zero-length spring elements appropriately placed in the beam-column interface. The model was calibrated against experimental results and found to accurately simulate the connection behaviour. A prototype building was selected and designed as a conventional steel moment-resisting frame (MRF) according to Eurocode 8 or as a self-centering steel MRF (SC-MRF) using the connection with WHPs. Seismic analyses results show that the conventional MRF and the SC-MRF have comparable peak storey drifts, and highlight the inherent potential of the SC-MRF to eliminate damage in beams and residual drifts. The paper also shows that repair of damage in the conventional MRF will be costly and disruptive after the design basis earthquake, and, not financially viable after the maximum considered earthquake due to large residual drifts.     

Comparison of horizontal ground displacements in Avonside area,Christchurch from air photo,LiDAR and satellite measurements regarding pipeline damage assessment

Recent earthquakes show that pipeline damage is severe in the areas where permanent ground deformations (e.g., liquefaction zones) occur. Ground movement hazard to pipeline systems can be assessed by using ground displacement measurements around the location of pipelines. There are many different ways of measuring ground displacements after an earthquake occur. This paper compares displacements measured in Avonside area, Christchurch, NZ, by using four different ways with respect to their effects on pipeline damage assessments. They are air photo, satellite, high resolution light detection and ranging (LiDAR) surveys data presented at 4- and 56-m grids acquired before and after the M_w6.2 22 February 2011 earthquake. Avonside area was in the liquefaction zones of the 22 February 2011 earthquake. Where possible, benchmark measurements were also included in the comparisons. In this study, the focus was on asbestos cement and cast iron water pipelines as the length of the pipelines and the number of damages in the study area was much higher compared to other pipe materials, providing sufficient repair rate data passing the screening criteria to develop linear regressions. The correlations between pipeline damage and lateral ground strains were developed by calculating the horizontal strains from these four different type displacements. The comparisons show that satellite imagery is good for estimating total movements but not so good for estimating lateral strains and conversely LiDAR surveys are not so good for estimating total movements, but much better for estimating lateral strains. Hence, pipeline damage correlations with LiDAR calculated strains provide higher determination coefficient (r²) value. The results of comparisons are presented and discussed.