本文關(guān)鍵詞： 部分預(yù)應(yīng)力梁 鋼骨 超高強(qiáng)混凝土 抗彎性能 疲勞荷載　出處：《大連理工大學(xué)》2014年博士論文　論文類型：學(xué)位論文

【摘要】：采用超高強(qiáng)混凝土材料,同時應(yīng)用鋼骨混凝土和部分預(yù)應(yīng)力技術(shù)形成了一種新型的組合梁——部分預(yù)應(yīng)力鋼骨超高強(qiáng)混凝土梁。該型式的組合梁利用了超高強(qiáng)混凝土抗壓強(qiáng)度高、耐久性優(yōu)異和可有效控制截面等特點,提高梁的配筋率、承載能力、耐久性和減輕自重；利用部分預(yù)應(yīng)力技術(shù)提高了梁正常使用極限狀態(tài)下的抗裂性能,并且部分預(yù)應(yīng)力技術(shù)相比全預(yù)應(yīng)力技術(shù)更加有利于梁的延性性能；利用內(nèi)置鋼骨改善了超高強(qiáng)脆性破壞導(dǎo)致極限承載力狀態(tài)后承載力驟降的現(xiàn)象,改善梁的延性性能和耗能能力。因此,部分預(yù)應(yīng)力鋼骨超高強(qiáng)混凝土梁非常適用于大跨重載橋梁和超高層建筑結(jié)構(gòu)轉(zhuǎn)換梁。 目前,僅有我國對預(yù)應(yīng)力鋼骨混凝土結(jié)構(gòu)已經(jīng)開展了一定的研究,取得了一些成果。但對于部分預(yù)應(yīng)力鋼骨超高強(qiáng)混凝土結(jié)構(gòu)的研究文獻(xiàn)報道較少。本文采用試驗研究、理論分析與數(shù)值模擬計算相結(jié)合的方法,對部分預(yù)應(yīng)力鋼骨超高強(qiáng)混凝土梁的靜力荷載和疲勞作用下的抗彎性能進(jìn)行了研究。本文所做的主要工作如下： (1)進(jìn)行了4根部分預(yù)應(yīng)力超高強(qiáng)混凝土梁靜力荷載下的抗彎性能試驗。研究了預(yù)應(yīng)力筋高度和預(yù)應(yīng)力筋配筋率對試件受彎性能的影響。試驗結(jié)果驗證了試件平截面假定的成立,依據(jù)現(xiàn)行混凝土結(jié)構(gòu)設(shè)計規(guī)范中的抗彎計算理論,給出了部分預(yù)應(yīng)力超高強(qiáng)混凝土梁的正截面抗彎承載力計算公式。依據(jù)現(xiàn)行規(guī)范中的裂縫寬度計算理論,通過引入預(yù)應(yīng)力筋高度對等效直徑的影響系數(shù)k1和對構(gòu)件特征系數(shù)acr的修正,給出了部分預(yù)應(yīng)力超高強(qiáng)混凝土梁的最大裂縫寬度計算公式。 (2)進(jìn)行了20根部分預(yù)應(yīng)力鋼骨超高強(qiáng)混凝土梁靜力荷載下的抗彎性能試驗。研究了試件的破壞形態(tài)、荷載一撓度曲線、跨中截面應(yīng)變和裂縫開展模式,系統(tǒng)分析了預(yù)應(yīng)力筋張拉控制應(yīng)力、非預(yù)應(yīng)力受拉鋼筋配筋率、鋼骨偏心率、鋼骨含鋼率、預(yù)應(yīng)力筋高度和預(yù)應(yīng)力筋配筋率等試驗因素對試件承載力、抗彎剛度和彎曲延性的影響規(guī)律。依據(jù)現(xiàn)行的兩種鋼骨混凝土結(jié)構(gòu)設(shè)計計算理論,分別給出了基于截面變形協(xié)同分析法和疊加法的部分預(yù)應(yīng)力鋼骨超高強(qiáng)混凝土梁的正截面抗彎承載力計算公式,并對兩種計算方法的適用性進(jìn)行了對比分析。采用分階段剛度疊加法并考慮了核心約束混凝土的剛度貢獻(xiàn),提出了部分預(yù)應(yīng)力鋼骨超高強(qiáng)混凝土梁各階段的截面剛度計算公式,進(jìn)而采用結(jié)構(gòu)力學(xué)計算方法給出了試件的跨中撓度計算公式。引入了預(yù)應(yīng)力筋、鋼骨下翼緣和腹板位置對等效直徑的影響系數(shù)k11、k2和k3,給出了部分預(yù)應(yīng)力鋼骨超高強(qiáng)混凝土梁的最大裂縫寬度計算公式。通過與部分預(yù)應(yīng)力超高強(qiáng)混凝土梁的試驗結(jié)果對比,分析了內(nèi)置鋼骨對試件的承載力、彎曲延性、能量消耗和裂縫開展模式的影響。 (3)提出了綜合配筋指數(shù)的計算公式,采用綜合配筋指數(shù)對18根部分預(yù)應(yīng)力鋼骨超高強(qiáng)混凝土梁和4根部分預(yù)應(yīng)力超高強(qiáng)混凝土梁的抗彎受力性能進(jìn)行分析。采用數(shù)理統(tǒng)計的方法,擬合出了綜合配筋指數(shù)作為單一變量的部分預(yù)應(yīng)力鋼骨超高強(qiáng)混凝土梁的極限承載力、位移延性系數(shù)和正常使用極限狀態(tài)所受彎矩等級的預(yù)測公式。 (4)結(jié)合試驗結(jié)果,采用ANSYS有限元分析軟件對部分預(yù)應(yīng)力鋼骨超高強(qiáng)混凝土梁的抗彎性能進(jìn)行數(shù)值仿真分析。分析階段為從開始加載到試件達(dá)到承載力極限狀態(tài),數(shù)值分析結(jié)果與試驗結(jié)果基本一致,驗證了ANSYS有限元模型的正確性。 (5)進(jìn)行了4根部分預(yù)應(yīng)力鋼骨超高強(qiáng)混凝土梁和1根部分預(yù)應(yīng)力超高強(qiáng)混凝土梁疲勞荷載下的抗彎性能試驗。分析了試驗梁的荷載-撓度曲線變化規(guī)律、抗彎剛度的退化規(guī)律、裂縫寬度擴(kuò)展規(guī)律和非預(yù)應(yīng)力受拉鋼筋的拉應(yīng)變隨疲勞次數(shù)的變化規(guī)律。分別給出了試件剛度降低系數(shù)、最大裂縫寬度變化和非預(yù)應(yīng)力受拉縱筋的應(yīng)力幅值比與疲勞次數(shù)的關(guān)系曲線。上述曲線可用于預(yù)測部分預(yù)應(yīng)力鋼骨超高強(qiáng)混凝土梁的疲勞壽命。
[Abstract]:A new composite beam _ partial prestressed steel - bone ultra - high strength concrete beam is formed by using ultra - high strength concrete . The composite beam of this type has the characteristics of high compressive strength , excellent durability and effective control of cross section . At present , only China has carried out a certain research on prestressed reinforced concrete structure , and some results have been obtained . However , it has been reported less in the research literature of some prestressed reinforced concrete structures . The experimental research , theoretical analysis and numerical simulation are used to study the bending performance of some prestressed reinforced concrete beams under static load and fatigue . The main work is as follows : ( 1 ) The bending performance test under static load of 4 partial prestressed high strength concrete beams is carried out . The influence of the height of the prestressed tendon and the reinforcement ratio of the prestressed rib on the bending performance of the test piece is studied . The calculation formula of the bending bearing capacity of the positive section of the partially prestressed high strength concrete beam is given according to the theory of bending calculation in the current specification of the concrete structure . According to the calculation theory of crack width in the current specification , the calculation formula of the maximum crack width of the partially prestressed ultra - high strength concrete beam is given by introducing the influence coefficient k1 of the height of the prestressed rib on the equivalent diameter and the correction of the characteristic coefficient acr of the component . ( 2 ) The bending performance test under static load of 20 partial prestressed reinforced concrete beams is carried out . The formulas for calculating the flexural rigidity and bending ductility of partial prestressed reinforced concrete beams based on cross section deformation cooperative analysis method and superposition method are analyzed in this paper . ( 3 ) The calculation formula of composite reinforcement index is put forward , and the bending stress properties of 18 partial prestressed reinforced concrete beams and 4 partial prestressed high strength concrete beams are analyzed by using the comprehensive reinforcement index . The ultimate bearing capacity , displacement ductility coefficient and the normal use limit state of the partial prestressed reinforced concrete beams with the combined reinforcement index as a single variable are fitted by mathematical statistics . ( 4 ) Based on the experimental results , the bending performance of some prestressed reinforced concrete beams is analyzed by ANSYS finite element analysis software . The analysis stage is from the beginning to the test piece to reach the ultimate bearing capacity limit state . The numerical analysis results are basically consistent with the experimental results , and the correctness of the ANSYS finite element model is verified . ( 5 ) The bending performance test of four partial prestressed reinforced concrete beams and one partial prestressed high strength concrete beam under fatigue loading is carried out . The variation law of the load - deflection curve of the test beam , the deterioration rule of the flexural rigidity , the crack width expansion law and the tensile strain of the non - prestressed tensile steel bar are analyzed . The relation curves of the stiffness reduction coefficient , the maximum crack width change and the stress amplitude ratio and the fatigue frequency of the non - prestressed tensile steel bar are respectively presented . The curve can be used to predict the fatigue life of the partially prestressed reinforced concrete beam .

【學(xué)位授予單位】：大連理工大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2014
【分類號】：TU398.9

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 支運(yùn)芳,王敢峰,李立仁,陳永慶,甘民;集中荷載作用下超高強(qiáng)混凝土無腹筋梁抗剪強(qiáng)度的試驗研究[J];重慶工學(xué)院學(xué)報;2005年03期

2 姜睿;;Seismic ductility of very-high-strength-concrete short columns subject to combined axial loading and cyclic lateral loading[J];Journal of Chongqing University(English Edition);2007年03期

3 王連廣,劉莉,崔敬奇;預(yù)應(yīng)力鋼與高強(qiáng)混凝土組合梁徐變效應(yīng)分析[J];東北大學(xué)學(xué)報;2005年07期

4 徐世p，

本文編號：1538953