本文選題：土木建筑工程 + 復(fù)合材料��； 參考：《吉林大學(xué)學(xué)報(bào)(工學(xué)版)》2017年03期

【摘要】：采用真三軸設(shè)備對(duì)100mm×100mm×100mm的立方體混凝土試塊進(jìn)行靜態(tài)加載。首先,保持三個(gè)軸向的應(yīng)力相同,施加應(yīng)力到設(shè)計(jì)值p。然后,在保持最小主應(yīng)力(Z軸)恒定并且X軸應(yīng)變速率與Y軸應(yīng)變速率之比也恒定的條件下,單調(diào)地增加Y軸應(yīng)變。通過(guò)這種復(fù)雜加載試驗(yàn),研究了混凝土的強(qiáng)度和體積特征。結(jié)果表明:在應(yīng)力-應(yīng)變混合路徑加載的真三軸試驗(yàn)下,混凝土的抗壓強(qiáng)度隨著最小主應(yīng)力的增大而增大,隨著加載應(yīng)變速率比的增大而線性遞減,都大于單軸抗壓強(qiáng)度,最高可達(dá)單軸抗壓強(qiáng)度的3.4倍;混凝土試塊在只經(jīng)歷靜水壓的加載歷史時(shí),初始剪切模量不受影響,不同組剪應(yīng)力-剪應(yīng)變關(guān)系曲線初始段都存在重合現(xiàn)象。峰值體積應(yīng)變隨著最小主應(yīng)力和應(yīng)變速率比的增大而增大,體積先減小后增大,出現(xiàn)擴(kuò)容現(xiàn)象;當(dāng)最小主應(yīng)力為10MPa時(shí),混凝土的峰值強(qiáng)度和峰值體積壓應(yīng)變幾乎同時(shí)出現(xiàn),并隨著最小主應(yīng)力的增大,兩者出現(xiàn)的時(shí)間間隔增大,峰值體應(yīng)變滯后。
[Abstract]:The cubic concrete specimen of 100mm 脳 100mm 脳 100mm is loaded statically by true triaxial equipment. First, keep the three axial stresses the same and apply the stress to the design value p. Then, under the condition that the minimum principal stress is kept constant and the ratio of X axis strain rate to Y axis strain rate is also constant, the Y axis strain is monotonously increased. The strength and volume characteristics of concrete are studied through this complex loading test. The results show that the compressive strength of concrete increases with the increase of the minimum principal stress and decreases linearly with the increase of the strain rate ratio, and is higher than that of the uniaxial compressive strength under the true triaxial test under the stress-strain mixed path loading. The maximum uniaxial compressive strength is 3.4 times, and the initial shear modulus is not affected when the concrete specimen only experiences the loading history of hydrostatic pressure, and the initial section of the different groups of shear stress-strain relationship curves is overlapped. The peak volume strain increases with the increase of the minimum principal stress and strain rate ratio, and the volume decreases first and then increases, and then increases, and when the minimum principal stress is 10MPa, the peak strength and the peak volume compressive strain of concrete almost appear at the same time. With the increase of the minimum principal stress, the time interval between the two increases and the peak strain lags behind.
【作者單位】： 北京交通大學(xué)土木建筑工程學(xué)院;
【基金】：國(guó)家自然科學(xué)基金項(xiàng)目(51279003)
【分類號(hào)】：TU528
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本文編號(hào)：1794253