一、剪切型辽宁钢纤维的主要性能 The main properties of shear type steel fiber 1、抗拉强度 1. Tensile strength 为使钢纤维混凝土具有良好的力学性能,要求钢纤维具有一定的抗拉强度。钢纤维的抗拉强度,根据钢纤维的材质和生产工艺不同,其抗拉强度也有所区别。剪切型钢纤维的抗拉强度一般为380~800MPa。 In order to make steel fiber reinforced concrete have good mechanical properties, steel fiber must have certain tensile strength. The tensile strength of steel fiber varies according to the material and production technology of steel fiber. The tensile strength of shear steel fiber is generally 380~800MPa. 2、粘结强度 2. Bond strength 钢纤维的粘结强度,可按《钢纤维混凝土试验方法标准》(CECS13:89)用直接拉拔法测定钢纤维与水泥砂浆之间的粘结强度。 The bond strength of steel fiber can be measured by the direct drawing method of steel fiber concrete test method (CECS13:89). 由于钢纤维混凝土的破坏主要是钢纤维的拔出而不是拉断,因此钢纤维的增强主要取决于钢纤维混凝土基体界面的粘结强度。提高粘结强度除与基体的性能有关外,就钢纤维本身来说,应该从钢纤维的表面和形状来改善它与基体的粘结性能。为了提高钢纤维的粘结强度,常采用:使钢纤维表面粗糙化、截面呈不规则形,增加与基体的接触面积和摩擦力;将钢纤维表面压痕,或压成波形,增加机械粘结力;使钢纤维的两端异形化,将两端制成弯钩或大头形等,以提高其锚固力和抗拔力。
试验表明,异形钢纤维比平直形钢纤维的增强效果可提高约一倍。 The experiment shows that the reinforcing effect of profiled steel fiber can be approximately doubled than that of plain steel fiber. 3、硬度 3, hardness 各种钢纤维的表面硬度较高,在与混凝土搅拌时,一般不易发生弯折现象。钢纤维应能经受沿直径为3mm钢棒弯折90度不断。 The surface hardness of all kinds of steel fibers is high, and it is not easy to bend when mixed with concrete. Steel fibers should be able to withstand bending 90 degrees along the diameter of 3mm steel rods. 4、耐腐蚀性 4, corrosion resistance 浇筑在钢纤维混凝土内部的钢纤维,只要捣固密实,与空气隔绝,钢纤维一般不发生锈蚀现象。露于混凝土表面或在裂缝宽度超过0.25mm时,跨接在裂缝处的钢纤维,易发生腐蚀现象。二、钢纤维的几何参数和体积率 Two. The geometric parameters and volume rate of steel fiber 表示钢纤维几何参数的有钢纤维长度、直径(等效直径)及长径比。 The geometric parameters of steel fiber are steel fiber length, diameter (equivalent diameter) and aspect ratio. 钢纤维长度指钢纤维两端点间的直线距离,用Lf 表示,其尺寸可为15~60mm。 The length of steel fiber refers to the straight distance between the ends of the steel fibers. The size of the steel can be 15~60mm by Lf. 钢纤维截面的直径或等效直径(当钢纤维为非圆形截面时,其截面积相当于圆形截面面积时计算所得到的直径),用df 表示通常为0.3~1.2mm。 The diameter of the steel fiber section or the equivalent diameter (when the steel fiber is a non circular section, the diameter of the section is equivalent to the area of the circular section), which is usually expressed as 0.3~1.2mm by DF. 钢纤维的长径比即指钢纤维的长度与直径或等效直径之比,即Lf/ df,通常为30~100。 The ratio of length to diameter of steel fiber refers to the ratio of length to diameter or equivalent diameter of steel fiber, that is, Lf/ DF, usually 30~100. 钢纤维体积率,指钢纤维所占钢纤维混凝土体积的百分数。用pf 表示,它表明钢纤维在拌合料中掺入量的多少。