玄武岩纤维对水稳碎石基层强度的影响

Effect of Basalt Fiber on Strength of Cement-Stabilized Macadam Base

为了研究玄武岩纤维改良棱角性不良的破碎鹅卵石基层性能,该文基于正交试验确定了水泥稳定破碎鹅卵石中玄武岩纤维最佳掺量为1 kg/m^(3)(15 mm)+2 kg/m^(3)(25 mm),对水泥稳定破碎鹅卵石、水泥稳定破碎鹅卵石+最佳掺量的玄武岩纤维和水泥稳定碎石(石灰岩机轧碎石)3种工况混合料进行了无侧限抗压强度与劈裂强度试验。研究结果表明:受骨料棱角性的影响,水泥稳定碎石(石灰岩机轧碎石)混合料的强度优于水泥稳定破碎鹅卵石混合料;掺入玄武岩纤维的水泥稳定破碎鹅卵石混合料,随着龄期的增加,其强度增长较快,与未掺入纤维的水泥稳定破碎鹅卵石混合料相比,7 d抗压强度降低了0.08%,而14 d、28 d、60 d抗压强度提高了3.9%、17.1%、28.3%;7 d、14 d、28 d、60 d劈裂强度提高了4.3%、10.2%、19.0%、28.7%;在龄期45 d掺入纤维的水泥稳定破碎鹅卵石的强度达到水泥稳定碎石(石灰岩机轧碎石)的强度。

To study the performance of basalt fiber in improving the poor angularity of the crushed cobble base,based on the orthogonal test,this paper determined that the optimal dosage of basalt fiber in the cementstabilized crushed cobble was 1 kg/m^(3)(15 mm)+2 kg/m^(3)(25 mm).Besides,unconfined compressive strength and splitting strength tests were carried out on mixtures under three working conditions including the cement-stabilized crushed cobble,cement-stabilized crushed cobble with the optimal dosage of basalt fiber,and cement-stabilized macadam(limestone machine-crushed stone).The results show that influenced by the aggregate angularity,the strength of the cement-stabilized macadam(limestone machine-crushed stone)mixture is better than that of the cement-stabilized crushed cobble mixture.For the cement-stabilized crushed cobble with the optimal dosage of basalt fiber,with the increase in curing age,its strength increases rapidly.Compared with the cement-stabilized crushed cobble without a dosage of fiber,its compressive strength is decreased by 0.08%on the seventh day and increased by 3.9%,17.1%,and 28.3%on the fourteenth day,the twenty-eighth day,and the sixtieth day respectively,and its splitting strength is increased by 4.3%,10.2%,19.0%,and 28.7%on the seventh day,the fourteenth day,the twenty-eighth day,and the sixtieth day,respectively.On the forty-fifth day,the strength of the cement-stabilized crushed cobble with a dosage of fiber reaches the strength of the cement-stabilized macadam(limestone machine-crushed stone).