酸沉降环境下混凝土断裂韧度的试验研究

发布时间：2018-05-09 02:24

本文选题：混凝土 + 实验室加速腐蚀　；参考：《工业建筑》2017年07期

【摘要】：通过实验室加速腐蚀方式和三点弯曲试验研究酸雨腐蚀对混凝土断裂韧度的影响,得到在酸雨腐蚀条件下混凝土裂尖的劣化样貌以及断裂韧度的劣化情况。在模拟酸环境下,腐蚀深度随着浸泡时间的延长而增加,混凝土裂尖腐蚀层材料发生物理化学变化,并随着腐蚀时间的延长而变得松弛并产生微裂隙,导致混凝土裂纹尖端抵抗开裂的能力降低。三点弯曲试验结果表明:相比未腐蚀试件,腐蚀试件断裂韧度发生了明显改变,并且随腐蚀时间呈现出先增加后减小的趋势。断裂韧度的劣化过程受p H值的影响,溶液p H值越小,则腐蚀初期的性能强化时间越短,断裂韧度劣化越快。腐蚀层混凝土材料的劣化是导致混凝土力学性能下降的主要因素,通过试验得到了腐蚀混凝土断裂韧度和腐蚀深度间的关系曲线。
[Abstract]:The effect of acid rain corrosion on the fracture toughness of concrete was studied by accelerated corrosion in laboratory and three point bending test. The deterioration of crack tip and fracture toughness of concrete under acid rain corrosion was obtained. In the simulated acid environment, the corrosion depth increases with the prolongation of immersion time, and the corrosion layer material of concrete crack tip changes physicochemical, and becomes relaxed and produces microcracks with the prolongation of corrosion time. The ability to resist cracking at the crack tip of concrete is reduced. The results of three-point bending test show that the fracture toughness of the corroded specimens changes obviously compared with the uncorroded specimens, and increases first and then decreases with the corrosion time. The degradation process of fracture toughness is affected by pH value. The smaller pH value of solution is, the shorter the strengthening time is at the beginning of corrosion and the faster the deterioration of fracture toughness is. The deterioration of corroded concrete material is the main factor leading to the deterioration of mechanical properties of concrete. The relationship between fracture toughness and corrosion depth of corroded concrete is obtained by experiments.
【作者单位】：深地科学与工程教育部重点实验室四川大学建筑与环境学院;
【基金】：国家自然科学基金项目(11672194) 四川省科技计划项目(2014JY0002) 油气藏地质及开发工程国家重点实验室资助项目(PLN1505)
【分类号】：TU528

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