公路预制箱梁混凝土材料掺钢纤维下的力学特征研究

Research on Mechanical Characteristics of Highway Prefabricated Box Beam Concrete Materials with Steel Fibers

为研究高速公路预制箱梁混凝土材料的宏、细观力学特征,文章采用AC-1000力学试验设备与SEM细观扫描方法,开展了掺钢纤维混凝土的力学特征机制研究。研究表明,钢纤维含量不会影响混凝土试样应变特征,围压作用会改变混凝土应变发展特点,也会提高混凝土承载应力水平。随钢纤维含量的递增,混凝土承载应力提高,但在含量6%后增幅减小。钢纤维含量越多,细小裂隙数量越少,同时围压越大,混凝土裂隙数量越少,钢纤维成分对抑制细小裂隙的产生有促进作用。该研究成果对公路工程中混凝土材料的应用设计具有一定的参考价值。

In order to study the macroscopic and microscopic mechanical characteristics of precast box girder concrete materials for highways,this article uses AC-1000 mechanical testing equipment and SEM microscopic scanning method to conduct a study on the mechanical characteristics and mechanisms of steel fiber reinforced concrete.Research has shown that the steel fiber content does not affect the strain characteristics of concrete specimens,and the confining pressure effect can change the development characteristics of concrete strain and also improve the bearing stress level of concrete.With the increase of steel fiber content,the bearing stress of concrete increases,but the increase decreases after the content reaches 6%.The more steel fiber content there is,the fewer small cracks there are.At the same time,the larger the confining pressure,the fewer cracks there are in concrete.The composition of steel fiber has a promoting effect on inhibiting the formation of small cracks.This research result has certain reference value for the application design of concrete materials in highway engineering.