本文選題：預(yù)應(yīng)力連續(xù)梁 + 無黏結(jié)筋��； 參考：《同濟(jì)大學(xué)學(xué)報(bào)(自然科學(xué)版)》2014年12期

【摘要】：完成4根無黏結(jié)預(yù)應(yīng)力混凝土兩跨連續(xù)梁受力全過程試驗(yàn),對(duì)支座反力及控制截面彎矩重分布程度進(jìn)行分析.運(yùn)用非線性階段的預(yù)應(yīng)力次彎矩定義,將非線性階段連續(xù)梁總彎矩分解成次彎矩和荷載彎矩.研究加載全過程次彎矩和荷載彎矩的演化規(guī)律,提出了對(duì)初始次彎矩和彈性荷載彎矩分別調(diào)幅的無黏結(jié)預(yù)應(yīng)力混凝土連續(xù)梁彎矩調(diào)幅公式.采用已有文獻(xiàn)中一組試驗(yàn)梁對(duì)所提公式的計(jì)算精度進(jìn)行驗(yàn)證.研究結(jié)果表明,無黏結(jié)預(yù)應(yīng)力連續(xù)梁彎矩重分布的原因可以歸結(jié)為無黏結(jié)筋應(yīng)力的增長(zhǎng)以及連續(xù)梁各部分割線剛度比值的改變.承載力極限狀態(tài)下,次彎矩折減系數(shù)隨中支座綜合配筋指數(shù)的增大而增大,荷載彎矩調(diào)幅系數(shù)隨其增大而降低.文中彎矩調(diào)幅建議公式較已有公式更接近試驗(yàn)結(jié)果,可為設(shè)計(jì)規(guī)范中相關(guān)條款的制訂提供參考.
[Abstract]:Four unbonded prestressed concrete two-span continuous beams were tested during the whole process of loading, and the reaction force of the bearing and the distribution degree of the controlled cross-section moment were analyzed. By using the definition of pre-stress secondary moment in nonlinear stage, the total moment of nonlinear continuous beam is decomposed into secondary moment and load moment. The evolution law of secondary moment and load moment in the whole process of loading is studied. The formula of moment modulation of unbonded prestressed concrete continuous beam is presented, which is used to adjust the amplitude of initial secondary moment and elastic load moment respectively. The calculation accuracy of the proposed formula is verified by a group of experimental beams in the literature. The results show that the redistribution of bending moment of unbonded prestressed continuous beams can be attributed to the increase of the stress of unbonded tendons and the change of the ratio of Secant stiffness of each part of continuous beams. In the ultimate state of bearing capacity, the secondary moment reduction coefficient increases with the increase of the composite reinforcement index of the middle support, and the amplitude modulation coefficient of the load moment decreases with the increase of the composite reinforcement index of the middle support. The suggested formula of bending moment amplitude modulation is closer to the test result than the existing formula, which can be used as a reference for the formulation of relevant clauses in the design code.
【作者單位】： 同濟(jì)大學(xué)土木工程學(xué)院;
【分類號(hào)】：TU378.2
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本文編號(hào)：1831464