利用?100 mm SHPB分离式霍普金森压杆装置研究不同温度及加载速率下混凝土冲击变形韧性。结果表明，高温后混凝土峰值、流动应及冲击韧性均随加载速率增加而增加，应变率效应显著；试件峰前韧性比不断降低，峰后韧性比及韧性转化比逐渐升高；同一加载速率下温度升高总体上使混凝土峰值应变及流动应变增大、冲击韧性降低，试件峰前韧性比呈上升趋势，峰后韧性比及韧性转化比逐渐下降；200℃时其冲击韧性在低应变率下相对较小，在高应变率下超过常温水平。
Effects of temperature and impact velocity on impact deformation and toughness of concrete
In this paper, the impact deformation and toughness properties of concrete were studied under different temperatures and impact velocities by using a 100mm diameter split Hopkinson pressure bar (SHPB) equipment. The test results indicate that the peak strain, flow strain and impact toughness of concrete increase with strain rate, implying the obvious rate effect. Simultaneously, an increase of loading rate also leads to a decreasing pre-peak toughness ratio and makes the post-peak toughness ratio and toughness conversion ratio increase. For a giving loading rate, the increasing of temperature results in an enhancement of peak strain and flow strain a reduction in impact toughness and an increasing trend of pre-peak toughness ratio. Post-peak toughness ratio and toughness conversion ratio also consistently decrease with temperature. In addition, at 200℃, the impact toughness of concrete firstly decrease, then increase with strain rate as compared with that at room temperature.
1. Department of Airfield and Building Engineering, Air Force Engineering University, Xi’an 710038, China;
2. College of Mechanics and Civil Architecture, Northwest Polytechnic University, Xi’an 710072, China;
3. The Graduate School of Design in Air Force of Shenyang, Shenyang 110000, China
摘要利用100 mm SHPB分离式霍普金森压杆装置研究不同温度及加载速率下混凝土冲击变形韧性。结果表明，高温后混凝土峰值、流动应及冲击韧性均随加载速率增加而增加，应变率效应显著；试件峰前韧性比不断降低，峰后韧性比及韧性转化比逐渐升高；同一加载速率下温度升高总体上使混凝土峰值应变及流动应变增大、冲击韧性降低，试件峰前韧性比呈上升趋势，峰后韧性比及韧性转化比逐渐下降；200℃时其冲击韧性在低应变率下相对较小，在高应变率下超过常温水平。
Abstract：In this paper, the impact deformation and toughness properties of concrete were studied under different temperatures and impact velocities by using a 100mm diameter split Hopkinson pressure bar (SHPB) equipment. The test results indicate that the peak strain, flow strain and impact toughness of concrete increase with strain rate, implying the obvious rate effect. Simultaneously, an increase of loading rate also leads to a decreasing pre-peak toughness ratio and makes the post-peak toughness ratio and toughness conversion ratio increase. For a giving loading rate, the increasing of temperature results in an enhancement of peak strain and flow strain a reduction in impact toughness and an increasing trend of pre-peak toughness ratio. Post-peak toughness ratio and toughness conversion ratio also consistently decrease with temperature. In addition, at 200℃, the impact toughness of concrete firstly decrease, then increase with strain rate as compared with that at room temperature.
聂良学1，许金余1,2，任韦波1，何 强3. 不同温度及加载速率对混凝土冲击变形韧性影响[J]. 振动与冲击, 2015, 34(6): 67-71.
NIE Liang-xue1, XU Jin-yu1, 2, REN Wei-bo1, HE Qiang3. Effects of temperature and impact velocity on impact deformation and toughness of concrete. JOURNAL OF VIBRATION AND SHOCK, 2015, 34(6): 67-71.
[1] 李志武,许金余,白二雷,等.高温后混凝土SHPB试验研究[J].振动与冲击,2012,31(8):143-147.
LI Zhi-wu, XU Jin-yu, BAI Er-lei, et al. SHPB test for post-high-temperature concrete [J]. Journal of Vibration and Shock, 2013, 31(8):143-147.
[2] 王宇涛,刘殿书,李胜林,等.基于Φ75mm SHPB系统的高温混凝土动态力学性能研究[J].振动与冲击,2014,33(17):12-17.
WANG Yu-tao, LIU Dian-shu, LI Sheng-lin, et al. Dynamic performance of concrete based on a Φ75mm SHPB system under high temperature [J]. Journal of Vibration and Shock, 2014,33(17):12-17.
[3] Li Zhi-wu, Xu Jin-yu, Bai Er-lei. Static and dynamic mechanical properties of concrete after high temperature exposure[J]. Materials Science and Engineering: A, 2012,544:27-32.
[4] Ravichandran G, Subhash G. Critical appraisal of limiting strain rates for compression testing ceramics in a split Hopkinson pressure bar[J]. Journal of the American Ceramic Society, 1994,77(1):263-267.
[5] 陶俊林,秦李波,李奎,等.混凝土高温动态压缩力学性能试验[J].爆炸与冲击,2011,31(1):101-106.
TAO Jun-lin, QIN Li-bi, LI Kui, et al. Experiment investigation on dynamic compression mechanical performance of concrete at high temperature [J]. Explosion and Shock Waves, 2011,31(1):101-106.
[6] 贾福萍,王永春,渠艳艳,等.冷却方式和静置时间对高温后混凝土残余强度的影响[J].建筑材料学报,2011,14(3):400-404.
JIA Fu-ping, WANG Yong-chun, QU Yan-yan, et al. Influences of various cooling methods and standing time on residual strength of concrete after elevated temperature exposure[J]. Journal of Building Materials, 2011,14(3):400-404.
[7] 刘利先,吕龙,刘铮,等.高温下及高温后混凝土的力学性能研究[J]. 建筑科学,2005,21(3):16-20.
LIU Li-xian, Lü Long, LIU Zheng, et al. Investigation on the mechanical behavior of concrete at and after elevated temperature [J]. Building Science, 2005,21(3):16-20.
[8] Chang Y F, Chen Y H, She M S, et al. Residual stress-strain relationship for concrete after exposure to high temperatures [J]. Cement and Concrete Research, 2006,36(10):1999-2005.
[9] Tanyildizi H, Coskun A. The effect of high temperature on compressive strength and splitting tensile strength of structural lightweight concrete containing fly ash [J]. Construction and Building Materials, 2008,22(11):2269-2275.
[10] 王礼立.应力波基础[M].北京:国防工业出版社, 2005.
[11] 吕天启,赵国藩,林忠,等.高温后静置混凝土的微观分析[J].建筑材料学报,2003,6(2):135-141.
Lü Tian-qi, ZHAO Guo-fan, LIN Zhong, et al. Microscopic analysis of long standing concrete after high temperature[J]. Journal of Building Materials, 2003,6(2):135-141.
[12] Mehmet B K. Effect of cooling regimes on compressive strength of concrete with lightweight aggregate exposed to high temperature [J]. Construction and Building Materials, 2013,41:21-25.
[13] Labuz J F, Dail S T. Residual strength and fracture energy from plane-strain testing [J]. Journal of Geotechnical and Geoenvironmental Engineering, 2000,126(10):882-889.
[14] 金丰年,蒋美蓉,高小玲.基于能量耗散定义损伤变量的方法[J].岩石力学与工程学报,2004,23(12):1976-1980.
JIN Feng-nian, JIANG Mei-rong, GAO Xiao-ling. Defining damage variable based on energy dissipation [J]. Chinese Journal of Rock Mechanics and Engineering, 2004,23(12):1976-1980.
[15] 赵忠虎,谢和平.岩石变形破坏过程中的能量传递和耗散研究[J].四川大学学报(工程科学版),2008,40(2):26-31.
ZHAO Zhong-hu, XIE He-ping. Energy transfer and energy dissipation in rock deformation and fracture [J]. Journal of Sichuan University (Engineering Science Edition), 2008,40(2):26-31.
