不同龄期混凝土动态力学性能研究

Study on Dynamic Mechanical Properties of Concrete under Different Ages

对不同龄期(28,112,183,345,810,1 248,1 550d)的混凝土进行了不同应变速率(10^(-5),5×10^(-5),10^(-4),5×10^(-4),10^(-3),5×10^(-3),10^(-2)/s)下的单轴压缩试验,试件尺寸为Φ150 mm×300 mm,研究了龄期和加载速率对混凝土的力学性能影响。结果表明:1在同一龄期下,混凝土的峰值应力随着应变速率增长而增大;在同一应变速率下,混凝土的峰值应力随着龄期的增长而增大,800d后峰值应力趋于稳定;2在同一应变速率下,混凝土的吸能能力随着龄期的增长而增加,表现出了峰值应力与龄期之间相似的规律。

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.