884aa四虎影成人精品,99久久国产综合精品女图图等你,97在线观看永久免费视频,久久精品国产精品亚洲38,ⅵdeodesetv性欧美

（同濟(jì)大學(xué)建筑設(shè)計(jì)研究院（集團(tuán)）有限公司， 上海 200092）

［摘要］受塔筒內(nèi)部操作空間限制，單管通信塔法蘭螺栓預(yù)拉力很難施加到高強(qiáng)螺栓預(yù)拉力設(shè)計(jì)值P。為確定一個(gè)合理的預(yù)拉力，以防止因法蘭螺栓疲勞破壞而引起的結(jié)構(gòu)失效，基于時(shí)域法建立了單管通信塔法蘭螺栓疲勞損傷的分析流程。首先采用諧波疊加法模擬了風(fēng)荷載時(shí)程，然后基于有限元法分析了不同螺栓預(yù)拉力對(duì)法蘭受力性能的影響，并將該影響反映到時(shí)程分析中。最后基于獲得的螺栓應(yīng)力時(shí)程，采用雨流法和損傷累積理論計(jì)算了螺栓的疲勞損傷。典型算例表明，當(dāng)螺栓預(yù)拉力較小時(shí)，螺栓的疲勞損傷對(duì)預(yù)拉力變化極其敏感，而當(dāng)螺栓預(yù)拉力達(dá)到0-2P后，損傷值可降低到0-001量級(jí)且對(duì)預(yù)拉力的敏感性大為降低。考慮到擰緊后的預(yù)拉力損失，可將0-25P作為螺栓的最小安裝預(yù)拉力，該數(shù)值也可為其他類似結(jié)構(gòu)提供參考。

［關(guān)鍵詞］單管通信塔； 法蘭； 螺栓預(yù)拉力； 疲勞損傷

中圖分類號(hào)：TU398+.7文獻(xiàn)標(biāo)識(shí)碼：A文章編號(hào)：1002-848X(2018)13-0026-05

Effect of bolt pretension on fatigue damage for flange connected  communication monopole

Yang Rongchang

(Tongji Architectural Design (Group) Co., Ltd., Shanghai 200092, China)

Abstract:Limited by internal operating space, it is very difficult to apply the designed preload for high strength bolts (P) in flange connected  communication monopole. In order to obtain the reasonable pretension to prevent the structure from failure due to fatigue fracture of flange bolt, a process was established to get the fatigue damage for bolts in flange connected  communication monopole  based on time-domain method. Firstly, the time-history of wind load was simulated by the harmonic superposition method. Then the effect of bolt pretension on the mechanical performance of flange was analyzed by the finite element method, and this effect was considered subsequently in the time-history analysis. Finally, based on the obtained bolt stress time-history, the fatigue damage of the bolts were calculated using the rain flow method and the damage accumulation theory. A typical example shows that when the pretension of the bolt is small, the fatigue damage of the bolt is extremely sensitive to its change; but when the pretension of the bolt reaches 0-2P, the damage value can be reduced to 0-001 magnitudes and its sensitivity to the pretension is greatly reduced as well. Taking into account the pretension loss after tightening, a value of 0-25P can be used as the minimum installation pretension of the bolt, which could also be a reference for similar structures.

Keywords:communication monopole; flange; bolt pretension; fatigue damage

作者簡(jiǎn)介：陽榮昌，博士，工程師，Email:xinglingrongchang@163.com。