冻融循环下不同纤维掺量混凝土宏细观关系试验研究

Test Study on Macro-meso Relationship of Concrete with Different Fiber Content Under Freeze-thaw Cycle

为探究冻融循环下混杂纤维混凝土宏细观特性的关联性,开展以冻融循环周次及纤维体积掺量为变量的快速冻融循环试验。试验结果表明,不同冻融循环周次下,抗压强度与含气量、气泡间距系数及气泡平均弦长呈正相关关系、与气孔比表面积呈负相关关系,而冻融损伤量与气孔参数则呈相反规律,且均呈近似线性变化;冻融循环周次越大,抗压强度越低、冻融损伤量越大、含气量、气泡间距系数及气泡平均弦长也越大,而气孔比表面积越小;混杂纤维的掺入,优化了气孔结构,提高了抗冻性。

In order to explore the relationship between macro and micro characteristics of hybrid fiber reinforced concrete under freeze-thaw cycles, rapid freeze-thaw cycle tests were carried out with freeze-thaw cycles and fiber volume content as variables. The test results show that under different freeze-thaw cycles, the compressive strength has a positive correlation with air content, bubble spacing coefficient and average chord length of bubbles, and a negative correlation with specific surface area of pores, while the freeze-thaw damage and pore parameters have an opposite law, and they all change approximately linearly;The larger the freeze-thaw cycles, the lower the compressive strength, the greater the freeze-thaw damage, the greater the air content, the bubble spacing coefficient and the average chord length of bubbles, and the smaller the specific surface area of pores;The incorporation of hybrid fibers optimizes the pore structure and improves the frost resistance.