建筑类英文及翻译.doc

1、外文原文出处:Geotech ni cal. Geological, and Earthquake Engin eeri ng, 1, Volume 10, Seismic RiskAssessme nt and Retrofitti ng, Pages 329-342补充垂直支撑对建筑物抗震加固摘要：大量的钢筋混凝土建筑物在整个世界地震活跃地区有共同的缺陷。弱柱，在一个 或多个事故中，由于横向变形而失去垂直承载力。这篇文章提出一个策略关于补充安装垂直支撑来防止房子的倒塌。这个策略 是使用在一个风险的角度上来研究最近 实际可行的性能。混凝土柱、动力失稳 的影响、多样循环冗余的影响降低了建 筑系

2、统和组件的强度。比如用建筑物来 说明这个策略的可行性。1、背景的介绍：建筑受地震震动，有可能达到一定程度上的动力失稳，因为从理论上说侧面上有无限的位移。许多建筑物，然而，在较低的震动强度下就失去竖向荷载的支撑，这就是横向力不稳定的原因（见图16.1）。提出了 这策略的目的是为了确定建筑物很可能 马上在竖向荷载作用下而倒塌，通过补 充一些垂直支撑来提高建筑物的安全。 维护竖向荷载支撑的能力，来改变水平在过去的经验表明，世界各地的地震最容易受到破坏的是一些无筋的混凝土框架结 构建筑物。这经常是由于一些无关紧要的漏洞，引起的全部或一大块地方发生破坏，比 如整根梁、柱子和板。去填实上表面来抑制框架的内

3、力，易受影响的底层去吸收大部分 的内力和冲力。这有几种过去被用过的方法可供选择来实施：1、加密上层结构，可以拆卸和更换一些硬度不够强的材料。2、加密上层结构，可以隔离一些安装接头上的裂缝，从而阻止对框架结构的影响。3、底楼，或者地板，可以增加结构新墙。这些措施 （项目1、2和3）能有效降低自 重，这韧性能满足于一层或多层。然而，所有这些都有困难和干扰。在美国，这些不寻 常的代价换来的是超过一半更有价值的建筑。4、在一些容易受到破坏的柱子裹上钢铁、混凝土、玻璃纤维、或碳纤维第四个选项可以增加柱子的强度和延性，这足以降低柱子受到破坏的风险在大多数 的建筑物中。这个方案虽然成本比前面低，但是整体性能

4、也会降低，对比较弱的地板破坏会更加集中。加强柱子的强度在美国很流行，但它的成本依旧是很高的。在发展中国 家，这些先进的技术对某些种类的加料或加强，还不能够做到随心所欲这个程序的提出包含了另一个选择， 美国已经运用这个选择用来降低房子倒塌的风险。这个方法是增加垂直支 撑，来防止建筑在瞬间竖向荷 载作用下就倒塌（见图16.3）。 这是为支撑转移做准备的，当 柱子被剪切破坏和剪切衰弱时。这个补充支撑通常是钢结构、管道支撑或木材支撑。他们通常安装在单独的柱子上, 但（图16.3）钢柱也可以被放置在能承担的水平框架上。这种技术能有效的降低自重，从 而降低了建筑在瞬间竖向荷载下就遭到破坏。在水平方向的强烈

5、震动，产生的不稳定大 概很少被想到。补充的安装垂直技撑相对比较便宜。一些有用的空间可能通过安装支撑 被影响，可是这是一些微不足道的比较。在美国为建筑安装一些补充支撑现在非常流行Suppleme ntal Vertical Support as a Means for Seismic Retrofit ofBuildi ngsCraig D. Comarti nGeotech ni cal, Geological, and Earthquake Engin eeri ng, 1, Volume10, Seismic Risk Assessme nt and Retrofitti ng, Page

6、s 329-342Abstract A large nu mber ofcon crete buildi ngs in seismically active areas throughout the world exhibit a com mon deficie ncy. Weak colu mns, in one or more stories, lose vertical load-carry ing capacity as a result of lateral distorti on.This chapter prese nts a con ceptual strategy for r

7、etrofit compris ing the in stallatio n of suppleme ntal vertical supports to preve nt collapse. This procedure utilizes arisk-based perspective based on rece nt research on the realistic capacity of con crete colu mns, dyn amic in stability, and the effects of in-cycle degradati on of stre ngth in b

8、uild ing systems and comp onen ts. An example build ing is used to illustrate the applicati on of the con cept.1 In troducti on and Backgro undBuild ings subject to earthquake shak ing have a pote ntial to reach a point of dyn amic in stability at which they collapse due to theoretically un limited

9、lateral displaceme nt.Many build in gs, however, lose the ability to support vertical loads and collapse at smaller levels of shak ing in ten sity tha n that which would otherwise cause lateral dyn amic in stability (see Fig. 16.1). The procedures proposed here are inten dedto identify buildings pro

10、ne to preemptive vertical load collapse and improve their safety by the installation of supplemental vertical supports. Maintaining the capabilityto support vertical loads cha nges the critical collapse mechanism to lateral dynamic stability which occurs at larger and less probable lateral displacem

11、e nts (see Fig. 16.2). Experie nee in past earthquakes around the world in dicates that con crete frames in filled with unrein forced masonry (URM) have bee nparticularly prone to collapse. This most ofte n is due to a weak first story caused by the omissi on of all or a substa ntial porti on of the

12、 in fill to allow for retail, park ing, or other uses con ducive toope n spaces. The in fill in upper stories restrai ns frame acti on and forces the flexible lower floor to absorb most of the en ergy dema nd and drift.There are several alter natives for retrofit strategy that have bee n impleme nte

13、d in the past:1. The in fill on upper floors could be removed and replaced with less stiff and less stro ng materials.2. The in fill on upper floors could be isolated from the structure by in stalli ng joi nts with gaps to preve nt in teracti on with the frame.3. The lower floor, or floors, could be

14、 stre ngthe ned with new structural walls These Measures (Items 1,2, and 3) are effective in reduc ing the ductility dema nd in the weak story or stories. However, all of them are costly and intrusive. In the US, it is not unu sual for the costs of these types of retrofit to exceed half of the repla

15、ceme nt value of the buildi ng.4. Wrap the colu mns in the weak story with jackets of steel, con crete, fiberglass, or carb on fiber.The fourth opti on can in crease both the stre ngth and ductility of the colu mnseno ugh to reduce the collapse risk for most build in gs. The cost is somewhat less th

16、a n for the first three alter natives; however the overall performa nee would also be less with more damage focused in the weak floor. Column jacketing is popular in the US, but the costs can still be high. In developing countries, the advanced technologies for some types of jackets may not be readi

17、ly available.The procedure proposed here incorporates another alternative that has been used in the US to reduce collapse risk. This strategy is to provide supplemental vertical supports designed to prevent preemptive vertical load collapse (see Fig. 16.3). These are intended to support loads that a

18、re transferred from shear critical columns as they are damaged and begin to fail. The supplemental supports are typically steel shapes, pipe shoring, or timber shores. They are often installed near individual columns, but also can be placed beneath capable horizontal framing. This technique is effective in reducing collapse risk by avoiding the preemptive vertical collapse mode。The inten sity of shak ing required for lateral dyn amic in stability is gen erally higher and less likely to occur. The installation of supplemental vertical support