| 摘要: |
| 采用振动台提供扰动，以抗压强度、抗折强度和损伤度作为评价指标，研究了受扰龄期和扰动时间对混凝土力学性能的影响.结果表明：在贯入阻力值为107～148MPa时的扰动对混凝土强度影响最为显著，其最大抗压强度损失率达到25%以上，最大抗折强度损失率则超过30%.临近初凝和终凝时的扰动对混凝土影响较小，平均强度损失率在10%左右.扰动时间的延长对抗压强度影响不大，对抗折强度影响比较显著.扰动时间小于30min时，抗折强度降低较为平缓，平均强度损失率在10%左右；扰动时间为40min时，平均抗折强度损失率超过30%.贯入阻力值为107～148MPa，扰动时间为30min时，受扰混凝土损伤随龄期加剧，损伤演化值超过5%；扰动时间为40min时，由于初始损伤较大，未出现损伤随龄期加剧的现象. |
| 关键词: 混凝土 扰动 强度 损伤度 |
| DOI：103969/j.issn1007 9629201604004 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目（51578477）；河北省高等学校科学技术研究项目（QN2015250） |
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| Influence of Disturbance in Hardening Stage on Mechanical Properties of Concrete |
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PAN Huimin1, WANG Fengxian2, ZHAO Qingxin1
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1.Key Laboratory of Mechanical Reliability for Heavy Equipments and Large Structures of Hebei Province,Yanshan University, Qinhuangdao 066004, China;2.SPIC Ningjin Thermoelectricity Co., Ltd., Xingtai 055550, China
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| Abstract: |
| Influence of disturbance period and vibration time on the mechanical properties of concrete was investigated by analyzing the compressive strength, flexural strength and damage degree. Results show that disturbance has the biggest influence on concrete strength when the penetration resistance is 107 to 148MPa. The maximum compressive strength loss reaches above 25% and the maximum flexural strength loss is more than 30%. The disturbance closer to initial setting and final setting has smaller effect on concrete and the average strength loss is about 10%. The extension of vibration time has little effect on the compressive strength of concrete. Nevertheless, its influence on the flexural strength is more significant. Flexural strength of concrete reduces more gently and the average flexural strength loss is about 10% when the vibration time is less than 30min. And when the vibration time is 40min, the average flexural strength loss is more than 30%. The damage of concrete increases with age significantly and the damage evolution value exceeds 5% when the penetration resistance is 107 to 148MPa and the vibration time is 30min. The damage of concrete shows no growth with age when the vibration time is 40min due to the large initial damage. |
| Key words: concrete disturbance strength damage degree |
