高性能混凝土早龄期抗拉性能试验研究

Experimental Study on Tensile Properties of High Performance Concrete at Early Ages

关键词:  高性能混凝土,早龄期,极限拉应变,抗拉强度,拉伸弹性模量

Key words:  high performance concrete(HPC),early age,tensile strain capacity,tensile strength,tensile elastic modulus

摘要:

采用自行设计的试验装置,对高性能混凝土早龄期抗拉性能进行了试验研究.结果发现:高性能混凝土在硬化过程中的极限拉应变极高,并随龄期的增加迅速递减,大致在12 h达到最小值,然后又缓慢回升并渐趋稳定;1 d后的极限拉应变大体上呈现为水灰比越低,其值越高的趋势;高性能混凝土早期抗拉强度和弹性模量发展迅速,同龄期的轴心抗拉强度约为劈裂抗拉强度的0.96倍.

Abstract:

Tensile properties of high performance concrete(HPC) at early ages were experimentally studied with self-designed testing rig.The conclusions of the present study can be drawn as follows,(a) Testing rig adopted in this paper is able to effectively evaluate tensile properties of hardened HPC,(b) Tensile strain capacity of HPC is very high in the period of hardening,which rapidly decreases with age and minimum value is reached somewhat later(about 12 h) and(c) Tensile strength and tensile elastic modulus of HPC rapidly develops at early ages,uniaxial tensile strength is about 0.96 times splitting tensile strength.