不同强度混凝土静态破碎试验研究

Test Research on Static Cracking of Different Strength Concrete

将静态破碎剂在相同用量及相同拌合水温条件下,倒入强度等级分别为C20、C30、C40的混凝土预留孔中进行静态破碎试验,观察混凝土表面裂缝的扩展情况并记录反应过程中混凝土外表面应变变化规律。结果表明:随着混凝土强度等级的提高,混凝土外表面开始出现裂缝的时间逐渐推迟,裂缝扩展的宽度以及混凝土外表面出现裂缝的条数都随着混凝土强度等级的提高而逐渐缩小和减少。在反应过程中,随着混凝土强度等级的提高,混凝土外表面的应变出现明显波动的时间逐渐滞后,不同强度等级的混凝土的四个侧面中,始终有一个侧面产生拉应变,其余三个侧面产生压应变。

The same dosage of static cracking agent at the same temperature of water was poured into the reserved holes in concrete of different strength grade of C20, C30 and. C40 to do static cracking test. During the reaction, the surface cracks of concrete were observed and the regulation of strain changes was documented. The results showed that ： as the rise of concrete strength grade, time of cracking occurrence starting on the surface of the con- crete gradually postpones and the crack＇ s width and number on the surface of the concrete gradually decrease. During the reaction, as the rise of concret strength grade, the time at which significant fluctuation occurrence of strain on the surface of the concrete gradually postpones. In the four sides of different strength grade concrete, in one side tensile strain always appears, and in the remaining three lateral sides compressive strain.