How Does Steel Fiber Perfectly Combine with Concrete?

1. What is the mechanical principle of steel fiber?

The main properties of steel fibers include tensile strength and bond strength. Tests have shown that ordinary steel fibers are mainly damaged due to pulling out of steel fibers, not due to breaking of steel fibers. Therefore, the tensile strength of steel fiber can generally meet the requirements of use, and the bond strength between it and the concrete matrix interface is the main factor affecting the performance of steel fiber. In addition to being related to the performance of the matrix, the bond strength is also related to the shape and cross-sectional shape of the steel fiber itself. In general, the section of concrete under impact conditions is relatively flat, and the specimen is broken into 2 to 3 pieces, which are independent and not connected to each other, and the pieces are relatively large. In the process of steel fiber failure, the main crack is accompanied by multiple branch cracks, fine crack filling and steady-state micro cracks. At the same time, due to the traction and fiber pulling effect of the mesh structure caused by steel fibers, the true bad section of steel fibers is uneven, so it has a greater ability to absorb energy. There are more and thinner blocks in the seminar, and the edge of the test piece is severely damaged.

The chaotic distribution of short fibers in the steel fibers mainly hinders the expansion of micro-cracks inside the concrete and prevents the occurrence and development of macro-cracks. In the initial stage of loading (tensioning and bending), the cement base material and the fibers bear the external force together. When the concrete cracks, the fibers spanning the crack become the main bearers of the external force. Therefore, steel fiber has a series of superior physical and mechanical properties compared with ordinary concrete.

2. How is steel fiber perfectly combined with concrete?

The biggest difference between steel fiber reinforced concrete and ordinary concrete is that the effect is different. Not only can the surface layer be thinned, the utilization performance of the pavement can be improved, the life of the pavement can be improved, but also the cost can be saved and the construction period can be shortened. The emergence of steel fiber concrete is to solve the increasingly severe road damage situation. People's economic foundation is established, more and more people drive, and the burden on the road surface is increasing. For the damaged cement concrete pavement, the investment in renovating the road surface is huge, and the construction period is long, which affects traffic and pedestrian travel. The emergence of steel fiber reinforced concrete can solve this problem very well. As a new type of composite material, it has been widely used quickly, which can effectively control the concrete gap and improve the crack resistance of the entire composite material.

The shape of the steel fiber can be used to press a groove on the steel wire with a pinch roller when producing the steel fiber, so that the produced steel fiber has a better fitting force and can be better bonded to the concrete. At the same time, it can also be better embedded in the steel fiber group, thus greatly enhancing the strength of concrete.