發(fā)布時(shí)間：2018-05-05 07:14

  本文選題：局部減薄 + 壓力管道��； 參考：《廣西大學(xué)學(xué)報(bào)(自然科學(xué)版)》2017年01期

【摘要】：為求解含局部減薄缺陷水電站壓力管道的極限承載力,提出了該類管道極限分析的彈性模量縮減法。該方法定義了表征單元接近塑性屈服程度的無量綱參數(shù)—單元承載比,提出了動(dòng)態(tài)識(shí)別局部減薄管道高承載區(qū)域閾值基準(zhǔn)承載比的計(jì)算方法,建立了相應(yīng)的彈性模量調(diào)整策略,可通過基于塑性極限分析原理的線彈性迭代求解含局部減薄壓力管道的極限荷載。算例分析表明:本文方法具有良好的計(jì)算精度和適用性;21組缺陷結(jié)構(gòu)的計(jì)算結(jié)果與彈塑性增量法(EPIA)誤差均在8%以內(nèi);局部減薄軸向長(zhǎng)度、深度和周向長(zhǎng)度對(duì)極限荷載影響依次降低,減薄軸向長(zhǎng)度無量綱參數(shù)A/R0t超過2.4將可能使極限內(nèi)壓降低45%以上。本文方法可為含缺陷管道結(jié)構(gòu)極限分析和安全評(píng)估提供參考。
[Abstract]:In order to solve the ultimate bearing capacity of pressure pipes of hydropower stations with local thinning defects, a reduction method of elastic modulus is proposed for the ultimate analysis of this kind of pipelines. In this method, the dimensionless parameter-element bearing ratio, which characterizes the element near the plastic yield degree, is defined, and the calculation method for dynamically identifying the threshold reference load ratio of the high bearing region of the local thinning pipeline is proposed, and the corresponding adjustment strategy of the elastic modulus is established. The linear elastic iteration based on the plastic limit analysis principle can be used to solve the limit load of the pipeline with local thinning pressure. Numerical examples show that the calculation results of 21 groups of defective structures with good calculation accuracy and applicability are within 8% of the error of Elastoplastic incremental method (EPI), and the axial length of local thinning is reduced. The influence of depth and circumferential length on the ultimate load decreases in turn, and the thinning of the axial length with dimensionless parameter A/R0t above 2. 4 may reduce the limit internal pressure by more than 45%. This method can be used as a reference for limit analysis and safety assessment of pipeline structures with defects.
【作者單位】： 廣西大學(xué)土木建筑工程學(xué)院;廣西大學(xué)工程防災(zāi)與結(jié)構(gòu)安全教育部重點(diǎn)實(shí)驗(yàn)室;中國(guó)長(zhǎng)江三峽集團(tuán)公司烏東德工程建設(shè)部;
【基金】：國(guó)家自然科學(xué)基金資助項(xiàng)目(51469004) 廣西高等學(xué)校高水平創(chuàng)新團(tuán)隊(duì)及卓越學(xué)者計(jì)劃(桂教人[2013]38號(hào))
【分類號(hào)】：TV732.4

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本文編號(hào)：1846750