Study On Properties Of Coir Fiber Toughened Cementitious Materials

In this paper,coir fiber is used in cement-based materials,based on the preparation of uniformly dispersed,suitable strength,and good toughness coir fiber cement-based materials,by exploring the water-binder ratio,coir fiber length,fiber content and different maintenance methods The impact on the toughness of coir fiber cement-based materials to achieve the optimization of the basic mix ratio;subsequently,the surface modification of coir fibers to achieve the optimization of the coir fiber and cement-based interface,combined with fiber cement-based materials related toughness test results,The effects of different interface optimization methods on the mechanical properties of cement-based materials were compared to achieve micro-adjustment of the interface between fibers and cement-based materials.In addition,the energy storage and energy consumption behavior of coir fiber cement-based materials were studied.In order to clarify the dispersion mechanism of coir fibers in cement-based materials,the effects of the feeding sequence of quartz sand,superplasticizer,fly ash and silica fume were studied to further optimize the dispersion state of coir fibers.The results prove that: Orderly adding quartz sand,water reducing agent,fly ash and silica fume can gradually improve the fiber dispersion effect.In the study of the influencing factors of the toughness of cement-based materials,different water-binder ratios,fiber dosages,and fiber lengths were selected for physical and mechanical performance tests.With the toughness as the goal,a reasonable coir fiber material ratio was determined.Among them,when the content of quartz sand is 3.5%,the amount of water reducing agent is 1%,30% fly ash and 10% silica fume are mixed and mixed,the cement-based material has good dispersion(0.857),and the mechanical properties and toughness performance Both are excellent;two curing environments,standard curing and carbon curing,are selected for mechanical and toughness performance testing.According to the experimental results,it is found that standard curing can promote the toughness of coir fibers.Modification of coir fiber to achieve the optimization of the fiber cement-based interface,and then to study its impact on the strength and toughness of cement-based materials,and then to optimize the interface optimization method,coir fiber boiling treatment process research process,using The fiber water absorption rate characterizes the volume stability of the fiber treatment process.On the basis of the boiling treatment,the interface is reconstructed with alkali and silane respectively on the surface roughness and interface compatibility,and is indirectly characterized by the method of pulling out the monofilament The change law of the surface friction force after the interface modification,and based on the mechanical property test experiment,explore the influence of the two modification methods and the synthesis of the two modification methods on the performance of cement-based materials.In order to determine the effect of different modification methods on the toughness of fiber cement-based materials.Combined with the structural characteristics of coir fibers,a model of the coir fiber's own pipe wall structure and a model of the interaction between coir fibers and cement matrix are built;combined with the analysis of the fracture energy of the optimization process,the fiber length,dosage and energy storage of the cement matrix Theoretic analysis of energy dissipation mode;finally,during the modification process,the mechanical model of energy storage and energy dissipation modes that affect the toughness of the cement matrix was analyzed during boiling treatment,alkali treatment on the basis of boiling treatment,silane treatment,and comprehensive treatment.And the theoretical exploration of energy dissipation.