摘要
为研究不同高温状态下加载速率对砂岩动态力学特性的影响,采用自行组装50 mm分离式Hopkinson压杆(split hopkinson pressure bar,SHPB)高温试验装置,对25~1 000℃高温状态下的砂岩试件进行了6级加载速率的动态单轴压缩试验。结果表明:高温下砂岩的峰值强度与加载速率之间呈二次多项式增长;砂岩的峰值强度在200℃时,加载速率效应最明显,在1 000℃时,加载速率效应最弱。砂岩的峰值应变与加载速率之间呈线性增加。总体表现出一定的加载速率强化效应。不同温度下动态弹性模量的变化规律差别很大。从砂岩的破坏形态可知,加载速率对砂岩的影响不仅与温度有关还与其本身的性质有关。可见,加载速率对峰值强度、峰值应变及动态弹性模量的影响与温度密切相关。分析结果对高温环境下岩石工程稳定性、安全性以及相关岩体的爆破效应具有重要参考依据。
In order to study the effect of loading rate on dynamic mechanical properties of sandstone at different high-temperature,Dynamic uniaxial compression tests on sandstone at high temperature form 25℃to 1 000℃under six different loading rates was conducted by using the self assembled?50 mm SHPB(split hopkinson pressure bar)testing device.The result shows that the peak strength show a quadratic polynomial increased relationship with the loading rates at high temperature;the effect of loading rate of the peak strength of sandstone is the most obvious at 200℃,while is the weakest at 1 000℃.The peak strain of sandstone increases linearly.Showing an obvious loading rate strengthening effect.The variation of dynamic modulus of elasticity is different at different temperatures.From the failures form of sandstone,it can be seen that the effect of loading rate on sandstone is not only related to temperature but also its properties.It is concluded that the effect of loading rate on peak strength,peak strain and dynamic modulus of elasticity is closely related to temperature.The results of the study have important reference for the stability and safety of rock engineering in high temperature environment and the blasting effect of related rocks.
作者
吴明静
平琦
张号
WU Ming-jing;PING Qi;ZHANG Hao(Engineering Research Center of Mine Underground Projects,Ministry of Education,Anhui University of Science and Technology,Huainan 232001,China;Key Laboratory for Coal Mine Safety and Efficient Exploitation Jointly Built by Anhui Province and Ministry of Education,Anhui University of Science and Technology,Huainan 232001,China)
出处
《科学技术与工程》
北大核心
2018年第24期281-287,共7页
Science Technology and Engineering
基金
国家自然科学基金(51674008)
安徽省自然科学基金(1808085ME134)
安徽省博士后基金(2015B058)
安徽省质量工程项目(2016jyxm0283)资助
关键词
岩石力学
高温
加载速率
力学性能
rock mechanics
high temperature
loading rate
mechanical properties
