【摘要】：鋼筋混凝土結(jié)構(gòu)件長(zhǎng)期在疲勞荷載作用下會(huì)影響其正常使用,甚至危及人們生命財(cái)產(chǎn)安全。疲勞荷載作用下鋼筋混凝土結(jié)構(gòu)件的破壞是一個(gè)極其復(fù)雜的損傷累積過(guò)程。梁板式高樁碼頭在港口工程中應(yīng)用有很久的歷史,也是最主要的碼頭結(jié)構(gòu)形式之一。暴露在自然環(huán)境中的門(mén)機(jī)軌道梁受到的疲勞荷載不僅有門(mén)機(jī)荷載,同時(shí)還有溫度荷載等。門(mén)機(jī)軌道梁在這兩種疲勞荷載共同作用下,疲勞損傷逐漸累積直至發(fā)生破壞。因而對(duì)門(mén)機(jī)軌道梁在門(mén)機(jī)及溫度荷載共同作用下進(jìn)行疲勞性能研究,準(zhǔn)確識(shí)別出其危險(xiǎn)部位、損傷程度,預(yù)測(cè)其疲勞壽命是很有必要。本文以黃岡某在建梁板式高樁碼頭為依托,研究該高樁碼頭的門(mén)機(jī)軌道梁在門(mén)機(jī)及溫度荷載耦合作用下的動(dòng)力響應(yīng),并結(jié)合已有鋼筋、混凝土應(yīng)力壽命函數(shù)對(duì)門(mén)機(jī)軌道梁疲勞壽命進(jìn)行預(yù)測(cè)。本文的主要研究?jī)?nèi)容及結(jié)論如下:(1)通過(guò)對(duì)多種已有鋼筋及混凝土疲勞壽命預(yù)測(cè)模型進(jìn)行比較分析,然后從這些模型中選擇出適合門(mén)機(jī)軌道梁疲勞壽命預(yù)測(cè)的模型。最后分別對(duì)受壓區(qū)的混凝土和受拉區(qū)的鋼筋進(jìn)行疲勞壽命預(yù)測(cè)。本文還探討溫度、門(mén)機(jī)荷載等因素對(duì)門(mén)機(jī)軌道梁疲勞壽命的影響規(guī)律。(2)本文通過(guò)數(shù)值模擬探究門(mén)機(jī)軌道梁在門(mén)機(jī)及溫度荷載共同作用下的疲勞性能,分析發(fā)現(xiàn)門(mén)機(jī)及溫度荷載耦合作用下的耦合應(yīng)力并不是二者簡(jiǎn)單線(xiàn)性疊加。具體表現(xiàn)為:在門(mén)機(jī)荷載為350KN/輪不變的情況下,當(dāng)梁上下表面溫度差小于10℃時(shí),耦合應(yīng)力小于門(mén)機(jī)單獨(dú)作用下產(chǎn)生的應(yīng)力,此時(shí)溫度荷載所產(chǎn)生的應(yīng)力對(duì)門(mén)機(jī)軌道梁延長(zhǎng)疲勞壽命是有利的。當(dāng)溫度差大于10℃后,耦合應(yīng)力逐漸大于門(mén)機(jī)單獨(dú)作用下產(chǎn)生的應(yīng)力,但小于門(mén)機(jī)及溫度荷載單獨(dú)作用下產(chǎn)生應(yīng)力按線(xiàn)性疊加的應(yīng)力,此時(shí)溫度荷載所產(chǎn)生的應(yīng)力會(huì)降低門(mén)機(jī)軌道梁的疲勞壽命。(3)針對(duì)門(mén)機(jī)軌道梁在施工、運(yùn)營(yíng)可能出現(xiàn)的疲勞損傷,文中提出在鋼筋混凝土結(jié)構(gòu)件中摻入鋼纖維以延長(zhǎng)門(mén)機(jī)軌道梁疲勞壽命的措施。這對(duì)確保高樁碼頭結(jié)構(gòu)整體安全性能,提高經(jīng)濟(jì)效益意義重大。
[Abstract]:Reinforced concrete structure can affect its normal use and even endanger the safety of people's life and property under fatigue load for a long time. The failure of reinforced concrete structures under fatigue load is an extremely complicated damage accumulation process. Beam-plate high-pile wharf has a long history of application in port engineering and is one of the most important wharf structures. The fatigue load of portal crane track beam exposed to natural environment is not only door crane load, but also temperature load. Under the combined action of these two kinds of fatigue load, the fatigue damage of portal crane track beam accumulates gradually until failure occurs. Therefore, it is necessary to study the fatigue performance of portal crane track beam under the combined action of door crane and temperature load, identify its dangerous position, damage degree and predict its fatigue life accurately. In this paper, the dynamic response of the portal crane track beam of the high pile wharf under the coupling of the door crane and the temperature load is studied based on a beam-slab high pile wharf under construction in Huanggang, and combined with the existing steel bar. The concrete stress life function is used to predict the fatigue life of portal crane track beam. The main contents and conclusions of this paper are as follows: (1) through the comparison and analysis of various existing fatigue life prediction models of reinforced and concrete beams, the models suitable for predicting fatigue life of portal crane track beams are selected from these models. Finally, the fatigue life of concrete in compression zone and steel bar in tension zone are predicted. This paper also discusses the influence of temperature, portal crane load and other factors on the fatigue life of portal crane track beam. (2) the fatigue performance of portal crane track beam under the combined action of door crane and temperature load is studied by numerical simulation. It is found that the coupling stress under the coupling of the door crane and the temperature load is not a simple linear superposition of the two. The concrete performance is as follows: when the load of the portal crane is 350KN/ wheel invariant, when the temperature difference between the upper and lower surface of the beam is less than 10 鈩，

本文編號(hào)：2226974