輸電塔架的力學(xué)強(qiáng)度分析

機(jī)械設(shè)計(jì)制造及其自動(dòng)化論文，論文編號(hào):JX1318 論文字?jǐn)?shù):16784.頁(yè)數(shù):40 附任務(wù)書(shū)，開(kāi)題報(bào)告，文獻(xiàn)綜述,外文翻譯

 摘  要
 
 輸電塔架結(jié)構(gòu)是送電工程中的重要結(jié)構(gòu)，其結(jié)構(gòu)設(shè)計(jì)安全性意義重大。我國(guó)現(xiàn)行《電力設(shè)施抗震設(shè)計(jì)規(guī)范》GB 50260-96及《架空送電線路桿塔結(jié)構(gòu)設(shè)計(jì)技術(shù)規(guī)定》DL/T 5154-2002僅對(duì)500kV以下桿塔結(jié)構(gòu)做了下述規(guī)定：8度及8度以下時(shí)，自立式鐵塔可不進(jìn)行抗震驗(yàn)算。該規(guī)定尙缺乏充分的研究支持。另外，隨著電壓等級(jí)的提高，輸電塔架結(jié)構(gòu)的高度和重量也隨之增加，地震作用對(duì)結(jié)構(gòu)設(shè)計(jì)的影響加劇，是否需要進(jìn)行抗震驗(yàn)算，要充分考察結(jié)構(gòu)控制內(nèi)力才能確定。目前為止，結(jié)構(gòu)控制內(nèi)力的分析已成為工程設(shè)計(jì)和規(guī)程編制修訂亟待解決的課題之一。本文在總結(jié)已有研究資料和成果的基礎(chǔ)上，對(duì)輸電塔架結(jié)構(gòu)設(shè)計(jì)理論進(jìn)行了分析討論，并以華北電力設(shè)計(jì)院提供的典型塔型――大跨越塔和酒杯塔為工程背景，以空間桁架有限元桿系模型為理論基礎(chǔ)，考慮地震、風(fēng)、不同風(fēng)速和不同高度等工況，運(yùn)用SAP2000有限元軟件，建立了特高壓輸電分析模型，進(jìn)行了各塔架結(jié)構(gòu)的動(dòng)力特性和地震反應(yīng)分析，對(duì)比研究了非抗震和抗震兩種組合情況下，塔體各部分桿件的設(shè)計(jì)控制內(nèi)力，并總結(jié)風(fēng)速和高度影響下，各部分桿件內(nèi)力變化規(guī)律，進(jìn)而確定輸電塔架結(jié)構(gòu)是否需要進(jìn)行抗震驗(yàn)算，通過(guò)以上對(duì)比研究得到以下主要結(jié)論：
1)在進(jìn)行地震響應(yīng)分析的時(shí)候，現(xiàn)行規(guī)范的取前2~3個(gè)振型是不能滿足工程精度要求。本文建議參考建筑結(jié)構(gòu)規(guī)定的，取用質(zhì)量參與系數(shù)達(dá)到90%以上的振型個(gè)
數(shù)。
2)隨風(fēng)速增大，塔身主材考慮地震作用效應(yīng)組合與不考慮地震作用效應(yīng)組合桿件內(nèi)力比值逐漸減小。
3)橫隔面的受力相對(duì)較小，一般情況下無(wú)論是否考慮地震效應(yīng)組合其設(shè)計(jì)內(nèi)力
均不起控制作用，主要根據(jù)長(zhǎng)細(xì)比等條件控制結(jié)構(gòu)選材，但在設(shè)計(jì)過(guò)程中必須考慮到橫隔面對(duì)塔架變形的約束作用，適當(dāng)加強(qiáng)橫隔面部位桿件的構(gòu)造措施。
關(guān)鍵詞：超高壓輸電塔架 風(fēng)荷載 地震作用 控制內(nèi)力
ABSTRACT
 
Tower structure is very important in transmission line.Its security is very importantfor structure design.The current code which guide tower designing in transmission line,‘Code for design of seismic of electrical installations’ and‘TechnicalRegulation of design for tower and pole structures of overhead transmission line’ indicate that:it is not necessary that seismic checking calculation is done forself-supporting transmission tower if the seismic fortification intensity is 8 degree orunder 8 degree.There is not enough scientific basis about this define.Otherwise,alongwith the improvement of voltage grading,the height of transmission tower becomeshigher and higher,and the span of two towers becomes larger and larger.The earthquakefunction's influence to structure design turns worse,Whether carrying on anti-seismicchecking or not,controlling force play an important role.Now,one subject is the study ofcontrolling force in the course of structural design and code amendment.In this dissertation,on the basis of reviewing the study and design data available,thestructural theory of transmission tower is discussed,type tower-large span transmissiontower as engineering background and Space truss finite element method as theoreticalfoundation.Various load cases taken account such as:earthquake effect,wind load,etc,transmission tower model established by SAP2000 software,the dynamic characters andseismic response are analyzed.the controlling force of the elements on tower arecompared whether considering the earthquake effect or not.Then,compare the regularityof the elements’force with the change of wind speed and tower height.So we can getsome conclusion as following:
1)More modes should be considered according to the modal mass participation ratio when the seismic response of the structure was investinated.We suggest that numbers of the modes whether the modal mass participation ratio achieve 90%or not.
2)Force controlled by wind with wind speed variation and height below 185m,and
it don’t need seismic checking if the seismic fortification intensity is 8 degree or under 8degree.Because the span of two towers in tower-large span transmission tower is toolarge,constitution measures should be stiffened on the web materials of the cross arm.
3)Generally,whether considering seismic effect or not,the internal force of the diaphragms is not the main facts for its small value during materials selected,we usually select the materials according to slenderness ratio,but the constitution measures should be stiffened because of its confinement to tower.
Key words:High voltage transmission tower,Wind load,Seismic effect,control force

 目   錄
摘要 I
ABSTRACT II
第一章、緒論 8
1.1研究目的和意義 8
1.2輸電塔架結(jié)構(gòu)體系國(guó)內(nèi)外研究現(xiàn)狀 9
1.3本文主要研究工作 11
1.4技術(shù)路線 11
第二章、輸電塔架結(jié)構(gòu)設(shè)計(jì)基本原理 12
2.1輸電塔架的特點(diǎn)和種類 12
2.2空間桁架有限元法 14
2.2.1計(jì)算簡(jiǎn)圖 15
2.2.2質(zhì)量矩陣 15
2.2.3桿件坐標(biāo)變換與剛度矩陣 16
2.2.4塔架正則方程及其解 18
2.3塔體荷載 19
2.3.1導(dǎo)線及地線風(fēng)荷載標(biāo)準(zhǔn)值 19
2.3.2桿塔風(fēng)荷載標(biāo)準(zhǔn)值 20
2.3.3地震作用 20
2.4荷載效應(yīng)組合 22
2.4.2考慮地震作用效應(yīng)組合 23
2.5本章小結(jié) 23
第三章 輸電塔架不同有限元計(jì)算模型的結(jié)果對(duì)比 24
3.1工程背景 24
3.1.1軟件介紹 24
3.1.2酒杯塔ZB3 24
3.2 SAP2000有限元軟件建模 27
3.2.1基本假定 27
3.2.2有限元模型對(duì)節(jié)點(diǎn)的處理 27
3.2.3荷載處理及動(dòng)力特性分析方法 28
3.3 SAP2000模型與TTAP模型桿件內(nèi)力對(duì)比 28
3.3.1重力作用下桿件內(nèi)力對(duì)比 29
3.3.2風(fēng)作用下桿件內(nèi)力對(duì)比 30
3.5本章小結(jié) 31
第四章 典型塔型的分析結(jié)果 32
4.1本章主要分析內(nèi)容 32
4.2按不同風(fēng)速設(shè)計(jì)模型對(duì)比 32
4.2.1結(jié)構(gòu)動(dòng)力特性對(duì)比 33
4.2.2內(nèi)力對(duì)比分析 34
4.3本章小結(jié) 38
第五章 結(jié)論 40
致  謝 41