为研究不同长度玄武岩纤维（BF）喷射混凝土力学性能随龄期发展的规律，设置相同掺量、不同长度纤维工况，比较喷射混凝土不同龄期基础力学性能试验结果，探究玄武岩纤维混凝土强度发展规律。研究结果表明： 1）3种长度（6、16、50 mm）BF掺入对喷射混凝土抗压强度和劈裂抗拉强度均有所提高，前期随龄期增长快，后期增长较慢，长度变化对强度提升效果影响存在差异。2）综合评价，抗压强度排序为BF-16＞BF-50＞BF-6。3）经曲线拟合分析可知，BF混凝土抗压强度和劈裂抗拉强度近似满足公式y=a×xb的关系。4）3种长度（6、16、50 mm）BF掺入后，混凝土抗剪强度随龄期发展存在明显的阶段性特征，BF对喷射混凝土抗剪强度起负作用。5）弯曲韧性试验中，BF喷射混凝土初裂荷载有所提升，但不存在明显裂后韧性。6）BF长度对混凝土初裂荷载发展不存在明显优劣规律，综合考虑BF-16为最优长度。
In order to study the mechanical properties of
shotcrete with different basalt fiber (BF) lengths in different age,
experimental results of different working conditions under same amount of
fibers with different lengths are compared. The basic mechanical properties at
different ages and the development law of basalt fiber concrete are explored.
The results show that: (1) All of the three kinds of BF length (6, 16 and 50
mm) can improve the compressive strength and splitting tensile strength of
shotcrete, and with faster growth in the early stage, and slower growth in the
later stage, strength improving effect varys with lengths. (2) According to
comprehensive evaluation, the order of strength is BF16＞BF50＞BF6. (3)Through curve fitting analysis, the compressive strength and
splitting tensile strength of BF concrete satisfies the relationship of formula y=a×xb. (4) The shear strength of concrete presents obvious stage
characteristics in different age with three different BF lengths, and BF has
negative effect on the shear strength of shotcrete. (5)In bending toughness
test, the initial cracking load of BF shotcrete is improved, but there is no
obvious postcracking toughness. (6) The initial
cracking load of concrete does not change obviously with the length of BF, and
16 mm is the optimal BF length.
