爆破振动对新浇混凝土影响的试验研究

发布时间：2018-01-03 19:24

本文关键词：爆破振动对新浇混凝土影响的试验研究　出处：《振动与冲击》2017年02期 　论文类型：期刊论文

【摘要】：为探究新浇混凝土受爆破振动作用下的安全振速,以保证混凝土结构的可靠性,采用露天深孔爆破作为振源,对龄期为6 h、12 h、36 h、48 h和72 h的C40混凝土分别在2~10 cm/s的爆破振速下进行试验。通过测试各龄期试件在受振动扰动后的纵波波速及抗压强度,分析得出:龄期为6 h和12 h时,2.3 cm/s的爆破振速能够使混凝土产生大于0.05的损伤以及5%以上的强度折减;龄期为36 h和48 h时,能够对混凝土造成损伤和强度折减的振速为4 cm/s,36 h龄期为混凝土抗振能力提升的拐点;龄期为72 h时,混凝土表现出明显的抗振性能。最后,以损伤不大于0.05和强度折减不大于5%双重指标,给出龄期为6 h、12 h、36 h、48 h和72 h的混凝土安全振速分别为2 cm/s、2 cm/s、4 cm/s、5 cm/s、7cm/s。为完善新浇混凝土在爆破振动下的安全标准提供参考。
[Abstract]:In order to investigate the safe vibration velocity of newly poured concrete under blasting vibration and to ensure the reliability of concrete structure, the open-pit deep-hole blasting is used as the vibration source, and the age of the new pouring concrete is 6 h ~ 12 h ~ (36 h). 48 h and 72 h C40 concrete were tested under blasting vibration velocity of 2 ~ 10 cm/s respectively. The longitudinal wave velocity and compressive strength of specimens at different ages were measured after vibration disturbance. The results show that the blasting vibration velocity of 2. 3 cm/s at the age of 6 h and 12 h can make the concrete damage more than 0. 05 and reduce the strength of concrete by more than 5%. When the age is 36 h and 48 h, the vibration velocity which can cause damage and strength reduction to concrete is 4 cm / s ~ (36) h age, which is the inflection point of improving the anti-vibration ability of concrete. When the age is 72 h, the concrete exhibits obvious anti-vibration performance. Finally, according to the double indexes of damage less than 0. 05 and strength reduction less than 5%, the age of concrete is 6 h / 12 h / h ~ 36 h. The safe vibration velocities of concrete at 48 h and 72 h are 2 cm / s ~ 2 cm / s ~ 2 cm / s ~ 2 cm / s ~ 4 cm / s ~ (-1) 5 cm/s, respectively. 7 cm / s. Provides a reference for improving the safety standard of new cast-in-place concrete under blasting vibration.
【作者单位】：中国矿业大学(北京)力学与建筑工程学院;开封市质量技术监督检验测试中心;
【基金】：国家自然科学基金资助项目(51574247;10272109) 高等学校博士学科点专项科研基金(20100023110001) 中央高校基本科研业务费专项资金资助项目(2010QL05)
【分类号】：TU755
【正文快照】： 在爆破施工与浇注混凝土交叉并行施工的情况下,会引起爆破振动对临近新浇混凝土的扰动问题,如地下工程爆破开挖与浇筑混凝土支护围岩,水电工程中爆破开挖与大坝混凝土浇筑。工程资料与试验数据均表明,爆破振动对新浇混凝土产生不利影响,我国相关的规程和标准[1-2]均将3天内的

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