【作者】 张亮泉；

【导师】 李惠；

【作者基本信息】 哈尔滨工业大学 ， 防灾减灾工程与防护工程， 2009， 博士

【摘要】 随着我国社会的发展,经济实力的增强以及人口的城市化,对大跨度空间结构的需求越来越多,要求也在不断提高。众所周知,特定建筑材料建造一定结构形式的建筑物,其跨度存在着一个极限。目前的大跨度建筑多采用钢材,在已建成的建筑中最大跨度可达到200多米,要突破这一跨度极限,使用高强、轻质的新型材料,并合理选择结构形式是一种可行的途径。纤维增强复合材料(Fiber Reinforced Plastic,简称FRP)具有比强度高、比模量大、性能易于设计、易加工成型、抗腐蚀、耐疲劳等多种优越性能。这种材料既是一种材料又是一种结构。FRP作为结构材料比传统材料自重轻20%~50%,并且除可以作为承力构件,还具有自感知等功能。因此,FRP的应用日益广泛,从航空航天、国防到民用经济的各个领域,并已经进入土木建筑领域。本文以空间结构中最常用的网架结构为研究对象,以碳纤维复合材料(Carbon Fiber Reinforced Plastic,简称CFRP)为构建网架的基本材料,以圆管为构建网架的基本单元,深入系统地研究CFRP网架的静动力特性、动力特性与抗震能力,并与相同跨度、相同网格布置方式和相同构件截面尺寸的钢网架进行对比。本文主要研究内容如下:首先,设计并制造两组共6个CFRP圆管,进行单向拉压性能试验。研究其抗拉强度和直至破坏的拉伸应力-应变曲线,分析其破坏特征;研究其抗压强度和直至破坏的受压应力-应变曲线,分析试件受压破坏特征。利用CFRP圆管单向拉压本构模型数值计算上述试验试件的拉伸和受压应力-应变曲线,并与试验结果进行比较。第二,提出CFRP网架结构的设计方法,包括杆件强度设计原则、杆件的屈曲分析和CFRP网架结构的设计总原则。根据上述设计方法分别设计3种形式的平板网架,并采用通用有限元分析软件ABAQUS分析3种网架在自重和屋面荷载共同作用下的内力分布规律,及网架支撑数量发生变化时其内力分布的变化规律。第三,采用ABAQUS计算分析跨度、网格布置方式及杆件截面尺寸均相同的CFRP网架和钢网架分别在常遇和罕遇地震作用下的动力响应,比较二者内力分布规律和频率特性,进而比较分析二者的跨越能力,验证CFRP网架可以实现更大跨度的跨越。第四,基于静力弹塑性分析方法,分析CFRP网架在水平、竖向及三向荷载作用下的失效模式,建立基于位移的CFRP网架失效判断准则,给出CFRP网架失效模式控制设计建议。更多还原

【Abstract】 With the development of society and economy in our country, more and more people migrate to cities. The requirement of long span space structure increased and the request of people for these structures also increased. Structures with longer span are required. However, the span of structures with certain structural form and constructed with certain material has insurmountable limit. The long-span space structures are constructed mainly by steel at the present time, and the largest span of these structures can reach to 200m. To exceed this span limit, a feasible way is choosing reasonable structural form and using new materials, lighter but with higher strength.The fiber reinforced plastic (FRP) is just a lightweight and high strength material with many excellent properties, like high specific strength, high specific modulus, easy to be designed and constructed, and good corrosion and fatigue resistance. A structure made by FRP is about 20%-50% lighter than that made by steel. Furthermore, FRP can be used not only to support structural weight, but also as smart sensing material. Until now, FRP has been widely applied in various fields, such as aerospace, defense and civil engineering.One type of FRP material, the carbon fiber reinforced plastic (CFRP), is utilized in this dissertation as the basic material to construct the double-layer grids. Each bar element in the double-layer grids is tube element that is wholly constructed by CFRP material. The property of the CFRP double-layer grids under static and dynamic loads are investigated in this dissertation. Also, the earthquake resistance ability of the CFRP grids is investigated. Then the CFRP double-layer grids are compared with traditional steel grids which has the same span, grid and element section.The main contents are included as follows.First, six CFRP tubes that is divide into two groups are constructed. Performance tests for these CFRP tubes under uniaxial tension and compression load are carried out. The tension strength, together with the stress-strain curves of the specimens up to failure are measured. The failure characteristics of the tubes are observed and analyzed. Also, the compression strength, as well as the stress-strain curves under compression up to the failure of specimen are measured. The failure characteristics of the tubes under compression are analyzed. After that, the stress-strain curves of the specimens under tension and compression load are simulated by utilizing the constitutive model of CFRP tubes. The simulation results and compared with the experimental results.Second, the design method for CFRP double-layer grids is proposed, including the design principle of tube strength, the element buckling analysis method and the general design principle of CFRP double-layer grids. Three typical double-layer grids are designed according to the said design method. Then the finite element software, ABAQUS, is utilized to analyze the inner force distribution of these CFRP double-layer grids under the static load that including the deadweight of the grids and the roof board. The variation of inner force distribution with the arrangement pattern of bearings is also discussed.Third, the seismic responses of a CFRP double-layer grid and a steel double-layer grid under common earthquake and rare earthquake are calculated by ABAQUS. The two grids have the same span, grid arrangement and element section. The inner force distribution and frequencies are compared for these two double-layer grids. Also, the span ability of these two grids are analyzed and compared. The results indicate that the CFRP double-layer grid has better span ability.Finally, the failure mode of CFRP grids under horizontal load, vertical load and three-directional load respectively are analyzed based on the pushover analysis method. The judgement criterion for the failure of CFRP grid is proposed. Also, the design advices controlling the failure mode of the CFRP grid is proposed.更多还原