【正文】
,梁中縱向受力鋼筋采用HRB400級鋼筋,其余鋼筋采用HPB235級鋼筋,試計(jì)算踏步板TB 1梯段斜梁TL 1平臺(tái)板TB 2平臺(tái)梁TL 2,踏步尺寸為。: 荷載計(jì)算:踏步板傳來的荷載 斜梁自重 斜梁抹灰 總計(jì) 內(nèi)力計(jì)算:取平臺(tái)梁截面尺寸為,斜梁水平方向上的計(jì)算跨度為: 斜梁跨中截面彎矩及支座截面簡力分別為: :斜梁按T形截面進(jìn)行配筋計(jì)算,取,翼緣有效寬度按倒L形截面計(jì)算:按梁的跨度考慮: 按翼緣寬度考慮: 按翼緣高度考慮: 取首先按第一類T形截面進(jìn)行試算,計(jì)算簡圖見圖102: 結(jié)構(gòu)確定為第一類T形截面,故 圖102 斜梁的計(jì)算簡圖 選用2C12(故可按構(gòu)造配置箍筋,選用雙肢箍。取跨內(nèi)和支座截面處。:選用。 由于采用柱下獨(dú)立基礎(chǔ)時(shí),計(jì)算出基礎(chǔ)面積過大,故采用條形基礎(chǔ)。2) 翼板配筋計(jì)算;選用HPB235級鋼筋,翼板配筋截面有效高度查表得 選12鋼筋,間距130;實(shí)際配筋面積參考文獻(xiàn):[1] (GB/T501042001).[2] (GB500092001).[3] (GBJ1687).[4] (GB500072002). [5] 《建筑抗震設(shè)計(jì)規(guī)范》 (GB500112001)[6] (GB500102002).[7] (GB500682001).[8] 鄭照北,呂恒林,(上冊).徐州:中國礦業(yè)大學(xué)出版社,2000.[9] 王作興,[10] 工業(yè)與民用建筑畢業(yè)設(shè)計(jì)指導(dǎo),武漢工業(yè)大學(xué)出版社,1997[11] [12] 房屋建筑學(xué),中國建筑工業(yè)出版社,1995[13] 鋼筋混凝土房屋結(jié)構(gòu)設(shè)計(jì)與實(shí)例,上??萍汲霭嫔?,1992[14] 李廉錕,結(jié)構(gòu)力學(xué)。 and Xiaofeng Hu2Abstract: A new method for damage identification in large, massive civil structures is presented, which is based on the idea that dead load is redistributed when damage occurs in the structure. The method uses static strain measurements due to dead load only as input to the identification procedure. An analytical model of a fixedfixed beam is developed in which the damage is represented by a section of reduced flexural rigidity. The damage state is determined by the location, length, and severity of the stiffness reduction. A forward analysis of the beam response is first presented to illustrate how the dead load is redistributed for different damage scenarios. The inverse problem is defined by a constrained optimization problem and is solved using a genetic algorithm. The proposed method correctly identified damage in the beam for a wide range of locations and damage severities. The identification procedure, in general, has a greater degree of success with increasing damage severity. Results show that damage is difficult to identify when it is close to the inflection point of theundamaged beam, where the dead load strain is zero. The effect of measurement noise on the ability to identify damage is investigated in the panion paper.DOl: (ASCE)07339445(2006) 132:8(1254)CE Database subject headings: Dead loads。 Optimization。 thus the damage could not be successfully identified (FmTar and Doebling 1997). Staticbased techniques work under a similar premise as the dynamicbased techniques, onl5 using static excitations and measured responses. In this case a static load is applied to the structure and the response, typically displacement or strain, is measured at one or more locations. Sanayei and Onipede (1991) used a finite element model and measured deflections to determine the stiffness properties of the structure. Banan et al. (1994a,b) developed a framework for identifying parameters in a structure based on static response quantities. The problem was cast as a constrained, nonlinear minimization problem, using either a forceerror estimator or a displacementerror estimator. The problem was solved by recursive quadratic programming. The procedure was tested on a 25 member Bowstring truss. Hjelmstad and Shin (1997) used a similar approach along with an adaptive parameter grouping scheme and a data perturbation scheme to address the problems of sparce and noisy data. Sanayei and Saletnik (1996a,b) modified the procedure developed earlier by Sanayei and Onipede (1991) to use static strain measurements instead of displacements. Parameters were estimated by minimizing the error between the theoretical and。 Damage.Introduction:Structural health monitoring may be defined as the application of advanced technologies to the automated detection and assessment of deterioration or damage in a structural system. The concept,which has received considerable attention in recent years, involves the use of advanced sensors, microprocessors, munication systems, and algorithms to automatically sense, locate,assess, diagnose, and report on the condition of a structural system. Applied to a civil structure, health monitoring may be used to detect slow gradual changes in a structure due to sustained load or environmental factors, and/or to detect rapid changes due to rare, high intensity events, such as an earthquake, hurricane, or blast. Health monitoring can be utilized on an asneeded basis, or as part of a permanent, longterm health monitoring program. Methods for damage detection can generally be classified as either dynamic or staticbased techniques. The more popular dynamic techniques are based on the premise that when a structure is damaged, the associated change in the structure will result in a change in the natural frequencies, mode shapes, damping ratios, modal strain energies, or other dynamic characteristics of the system. By measuring one or more of these properties of the damaged structure (and in some cases the undamaged structure) the location and extent of damage could be identified. The dynamic procedures require some type of dynamic excitation。 Algorithms。中國建筑工業(yè)出版社,1997[16] [17] 陳希哲,土力學(xué)地基基礎(chǔ),清華大學(xué),1996[18] 郭繼武,建筑抗震設(shè)計(jì),高等教育出版社,1995[19] 梁興文,:科學(xué)出版社,2002.[20] 包世華,高層建筑結(jié)構(gòu)設(shè)計(jì)。基礎(chǔ)兩端挑出: 則基礎(chǔ)梁總長:取基礎(chǔ)及其以上填土重度,則基礎(chǔ)底面寬度b為 取b= m 按反梁法計(jì)算地基凈反力和基礎(chǔ)截面彎矩基底凈反力標(biāo)準(zhǔn)值:基礎(chǔ)可以看成在均布荷載作用下的三跨連續(xù)梁基礎(chǔ)的尺寸見圖111 圖111基礎(chǔ)尺寸圖 基礎(chǔ)計(jì)算簡圖見圖112 圖112基礎(chǔ)計(jì)算簡圖內(nèi)力圖見圖113,圖114 圖113基礎(chǔ)的M圖() 圖114 基礎(chǔ)的V圖(KN)::有效高度當(dāng)支座按第一類T行截面計(jì)算,跨內(nèi)按矩形計(jì)算計(jì)算過程見表111,表112 表111正截面強(qiáng)度計(jì)算截面端支座邊跨跨內(nèi)離端第二支座離端第二跨跨內(nèi) 1104276027231840選配鋼筋420920920620實(shí)配鋼筋面積 1257282728271885