不同钢纤维对粘结性能的影响 Influence of different steel fibers on bond properties 混凝土中水泥基体与骨料的界面是混凝土的薄弱环节, 对于钢纤维混凝土而言, 水泥基体和钢纤维的界面, 亦往往是钢纤维混凝土中最薄弱的环节, 水泥石和钢纤维的界面粘结主要是物理结合.所谓物理结合是由于水泥水化物与钢纤维界面间的粘着和机械啮合作用而引起的, 因此, 钢纤维的形状、表面状况、断面形状和钢纤维的材质对此类物理结合有很大的影响. The interface between the cement matrix and the aggregate is the weak link of concrete. For the steel fiber concrete, the interface between the cement matrix and the steel fiber is often the weakest link in the steel fiber concrete. The interface bonding of the cement and steel fiber is mainly the physical combination. The so-called physical combination is due to the cement hydrate and steel. The shape of the fiber, the surface condition, the shape of the section and the material of the steel fiber have a great influence on the combination of the fiber interface. 目前应用较多的钢纤维主要有以下几种: At present, more and more steel fibers are applied. (1) 钢丝切断制成的短纤维:该种纤维的制作工艺比较简单, 所得的钢纤维抗拉强度较高, 不足之处是其表面光滑, 因此与混凝土基体之间的粘结强度较低. (1) short fiber made of steel wire: the production process of this kind of fiber is relatively simple, the tensile strength of the steel fiber is high, the defect is its smooth surface, so the bond strength between the concrete and the concrete is low. (2) 薄板剪切钢纤维:该种纤维的制作工艺与第一种相似, 原料是同所需纤维长度一样宽的薄钢板, 再经剪切制成, 在剪切中钢纤维稍带弯曲和扭曲, 这样能增加粘结强度. (2) thin sheet shear steel fiber: the production process of this kind of fiber is similar to the first kind, the raw material is the thin steel plate with the same length as the required length, and then made by shear. In the shear, the steel fiber is slightly bent and twisted, which can increase the bond strength. (3)钢锭铣削钢纤维:采用钢锭为原料, 用铣刀进行切削制成的纤维, 这种纤维的特点是轴向发生扭曲, 并用通过改进刀具可以使纤维表面产生粗糙面, 此外, 前两种纤维在生产过程中表面或多或少会粘有油污等杂质, 而该纤维的生产方法可确保其表面的洁净.因此用该方法制得的钢纤维与混凝土基体的粘结强度要高于前两种钢纤维. (3) Steel Ingot Milling: fiber made of ingot as raw material and cutting with a milling cutter. The characteristics of this fiber are axial distortion, and the surface of the fiber can be produced by improving the cutting tool. In addition, the first two kinds of fiber can be produced in the process of production or more or less with oil pollution and other impurities, and the production of the fiber. The method ensures the cleanliness of the surface. Therefore, the bond strength between the steel fiber and concrete matrix produced by this method is higher than that of the first two kinds of steel fibers.