發(fā)布時間：2018-03-31 05:04

  本文選題：混凝土硬化變形　切入點：數(shù)字散斑相關(guān)方法　出處：《混凝土》2017年08期

【摘要】：通過CCD相機(jī)搭建試驗的數(shù)據(jù)采集系統(tǒng),以數(shù)字散斑相關(guān)方法對試驗中采集的散斑圖像數(shù)據(jù)進(jìn)行分析,研究混凝土試件硬化過程中試件表面變形場演化特征及其對后期受載破壞規(guī)律的影響。試驗結(jié)果表明:(1)混凝土硬化變形時空演化表現(xiàn)為變形緩慢增加、變形快速增加、變形穩(wěn)定3個階段特征;混凝土硬化變形時空演化過程是一個從拉、壓區(qū)域不斷調(diào)整到最終穩(wěn)定的動態(tài)過程,調(diào)整過程中在受拉區(qū)形成損傷集中區(qū);混凝土硬化變形場空間演化特征表現(xiàn)為由不均勻分布演化為拉、壓應(yīng)變區(qū)域呈條狀相間的分布狀態(tài)。(2)受載過程中裂紋在硬化變形受拉較大的區(qū)域開始發(fā)育,隨著荷載的增加裂紋沿著硬化過程中形成的條狀受拉區(qū)域擴(kuò)展成宏觀裂紋且試件表面裂紋具有等距分布特征。
[Abstract]:The experimental data acquisition system is built by CCD camera, and the speckle image data collected in the experiment are analyzed by digital speckle correlation method. The evolution characteristics of the surface deformation field of concrete specimens during the hardening process and its influence on the law of post-loading failure are studied. The experimental results show that the space-time evolution of concrete hardening deformation shows a slow increase in deformation and a rapid increase in deformation. The space-time evolution process of concrete hardening deformation is a dynamic process from tension and compression region to final stability, and the damage concentration zone is formed in the tensile zone during the adjustment process. The spatial evolution of the hardening deformation field of concrete is characterized by the evolution from uneven distribution to tension, and the crack begins to develop in the area where the hardening deformation is larger during the loading process, and the compressive strain region is in the form of a strip-like distribution state. With the increase of load, the crack propagates into macroscopic crack along the strip tensile region formed during the hardening process, and the crack on the surface of the specimen has the isometric distribution characteristic.
【作者單位】： 北方工業(yè)大學(xué)土木工程學(xué)院;
【基金】：國家自然科學(xué)基金(51474013)
【分類號】：TU528
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本文編號：1689249