关键词: 混凝土, 峰值应力, 应变速率, 龄期, 吸能能力

Abstract:

Uniaxial compression tests of cylinder specimens (diameter of 150 mm,and length of 300 mm) for concrete were carried out under different ages (28 d,112 d,183 d,345 d,810 d,1248 d,1550 d) and different strain rates (10^-5,5×10^-5,1×10^-4,5×10^-4,1×10^-3,5×10^-3,10^-2/s),and impacts of strain rate and age on mechanical properties of concrete were explored.The results show that:1)at the same age,peak stress of concrete increases with strain rate,and at the same strain rate, peak stress of concrete increases with age,but peak stress tends to be stable after the age of concrete is up to 800 d;2) when strain rate is given,capability of energy absorption of concrete increases with age,and the relationship between capability of energy absorption and age of concrete is similar with that of peak stress and age of concrete.

Key words: concrete, peak stress, strain rate, age, capability of energy absorption