Polypropylene Fiber Concrete Mechanics Performance Test

With coal mining depth gradually deepened, also follow the technical requirements of our increasingly high, but the deformation of rock and earth pressure increases with depth increases, our quality and safety and production efficiency have been severely affected. With the gradual improvement of people to explore the mechanism of shotcrete support, improvement and development of anchor, construction equipment and construction technology, shotcrete support has become a support series, can be divided into bolting, bolt shotcrete, shotcrete, anchor metal mesh shotcrete support. Shotcrete care in the field of coal has played a huge role in it, but it highlights the flaws are slowly, slowly with further research, the ensuing problems, but also have a variety of solutions that have not yet been fully perfect. Research Shotcrete reinforcement mechanism can be found:the ordinary amount of deformation of concrete sprayed layer can not meet the deformation of surrounding rock, though in recent years a variety of extensible bolt after another, but the shotcrete support the research is still no concrete sprayed layer significant breakthrough. In the roadway spray ordinary concrete, shortly after construction prone to cracks, flaking even evolved into a phenomenon, so that the loss of the supporting structure and supporting the role of the closed rock, especially in the number of new stretch After a long bolt have developed, the problem is particularly prominent.This thesis is not increasing the cost of roadway request, on the basis of structural shotcrete support mechanism based on the increase of the mechanical properties of spray-layer structure, while not reducing the safety and reliability of supporting system. The study found the roadway instead of polypropylene fiber concrete sprayed layer can effectively solve the problem of concrete cracking. The principle is:concrete cement the bond as a gelling material fibers, reinforcing the role played fine, so as to control the internal micro-cracks in the cement matrix, improved crack resistance of concrete. On the basis of the fiber reinforcement mechanism elaborated, were concrete strength and impermeability tests under different conditions, fiber content, fiber content summed up the change in performance can suffer to varying degrees, by testing analysis to determine the fiber the best dosage; layer of fiber reinforced concrete and ordinary concrete spraying spray layer numerical simulation and compare the results showed:fiber reinforced concrete with large deformation capacity, is conducive to the release of the rock pressure and allow a slight deformation of the surrounding rock give full play to the mechanical properties of the shotcrete support system This thesis is not increasing the cost of roadway request, on the basis of structural shotcrete support mechanism based on the increase of the mechanical properties of spray-layer structure, while not reducing the safety and reliability of supporting system. The study found the roadway instead of polypropylene fiber concrete sprayed layer can effectively solve the problem of concrete cracking. The principle is:concrete cement the bond as a gelling material fibers, reinforcing the role played fine, so as to control the internal micro-cracks in the cement matrix, improved crack resistance of concrete. On the basis of the fiber reinforcement mechanism elaborated, were concrete strength and impermeability tests under different conditions, fiber content, fiber content summed up the change in performance can suffer to varying degrees, by testing analysis to determine the fiber the best dosage; layer of fiber reinforced concrete and ordinary concrete spraying spray layer numerical simulation and compare the results showed:fiber reinforced concrete with large deformation capacity, is conducive to the release of the rock pressure and allow a slight deformation of the surrounding rock give full play to the mechanical properties of the shotcrete support system.Experimental results:Compared with ordinary concrete fiber concrete sticky, less rebound resilience is low, so that let the pressure effect is obvious, less prone to the phenomenon of stress concentration, so that a uniform distribution of stress again. This study opens up Shotcrete retaining new road, improved support structure, promote the development.