Research On The Effect Of Polypropylene Fiber On Mechanical Properties Of Solidified Tideland Sludge

The development of tideland sludge is an effective way to solve the contradict-tions of the people and land in coastal areas. Nowadays, the most commonly used sludge stabilization methods cost too much and put tremendous pressure on the environment, so it is becoming more and more important to study the new sludge stabilization methods. The current methods of the sludge stabilization include physical dehydration, heating and chemical stabilization. The previous two methods are used to deal with the small amount of sludge with high degree of treatment. More advanced method is the chemical stabilization way. The stabilization materials are mixed completely to the sludge to get the new kind of geotextile material, which have physical and mechanical properties advanced. This method can also produce the renewable resources, promoting recycling.The effect of the polypropylene fiber in concrete has been well discussed before by researchers, which has a great impact on the physical and mechanical properties of the concrete. However, now in the area of the sludge stabilization, the effect of the polypropylene fiber in curing sludge is still not clear, which will inevitably evolve into a new research topic in the study of the sludge stabilization.In this study, the same amount of cement and different content of polypropylene fiber with the same length or different length of polypropylene fiber with the same content were mixed into the sludge which was collected from the Jiao River tideland areas. Unconfined compressive strength tests, water content tests, shear strength tests, XRD and SEM tests were carried out on specimens with different curing time to explore the effect of the polypropylene fiber in the sludge stabilization. And then, a new idea of the sludge stabilization is proposed. The results show that the sludge curing effect is markedly improved by the addition of the polypropylene fiber. As to the curing sludge with the same curing time, when the content of the polypropylene fiber increases, the unconfined compressive strength and the cohesive strength greatly increase, and the internal frictional angle decreases; when the length of the polypropylene fiber increases, the unconfined compressive strength increases.