Study On The Effect Of Agent On Mechanical Properties Of Biomass Building Materials

In recent years, the human has been demanded of changing the production mode and lifestyle, and protecting the environment with the global environmental degradation. With this, we need to exploit new resources, energy and establish long-term green development mechanism. Thus, people began to use biomass material, and the technology developed rapidly. The agricultural straws is one of abundance renewable material resources in China, the annual production is more than 6 million tons. The straw, with the shorter regenertion cycle, has the characteristics of storability. Meanwhile, the country’s resources energy policies have been adjusting constantly. The traditional means of straw using have not suited for the new development. Problems of regional, seasonal structural and burned illegal remain existing in straw. Straw resource use rationalization becomes an important problem to be solved.At present, the straw stalk used as building materials are less than 20% in the world. The majority are product plywood with adhesive, waste plastic and so on. The studies of straw composite with Portland cement and other inorganic materials are less. The tissue composition and structure types of straw are particularity. The straw dissloution objects will affect the hydration condensation in hydration reaction. At the same time, the straw surface has bad bond area, which causes composites instability between straw and cementitious materials. Now the studies by domestic and overseas scholars mainly focused on the straw preprocessing, such as physical treatment, graft copolymerization, enzyme ect, to change the organizational structure of straw and improve the appropriate between straw and cementitious material. However, by single modified cannot solve the interfacial compatibility of the straw completely.By mixing differently urface wrap agent and coagulant early-strength agents, the paper analysis on the relationship between agent and biomass materials. At the same time, the paper researches to mixing amount of agent and performance of straw cement-based biomass materials. Through these methods, it provides in-depth study for theoretical basis.This paper studies the effects of agents on hydration characteristics of straw cement-based biomass materials. The results showed that the two agents abate straw to cement hydration inhibition coagulation, and improving the straw cement-based biomass materials strength. The compatibility coefficient CA increase with mixing amount of urface wrap agent adding. The effect of CaCl2 is the best for adding hydration heat. At the point of 8% of CaCl2, the Tmax reached 46℃, the CA resched 86.11%。This paper studies the effects of agents on compressive strength and flexural strength of straw cement-based biomass materials. The results showed that the strength enhance obviously by mixing agents. The early strength of straw cement-based biomass materials mixing water glass is much higher than mixing PVAc, but the later strength of straw cement-based biomass materials mixing PVAc is much higher than mixing water glass, the 28d compressive strength from 5.5MPa to 10.3MPa. The effect of CaCl2 is the best for coagulant and early-strength. The the early-strength growth of straw cement-based biomass materials mixing CaCl2 reached more than 300%. Meawhile the 28d compressive strength of straw cement-based biomass materials increased with coagulant early-strength agents adding, the 28d compressive strength from 5.5MPa to 7.6MPa..This paper studies the effects of agents on water resistant and anti-aging of straw cement-based biomass materials. The results showed that both of the urface wrap agent and coagulant early-strength agents would improve the durability. The water absorption is 0.087, softening coefficient is 0.087, wet-dry strength coefficient is 0.921, when the mixing of PVAc is 50%. Beside the effect of FeCl3 is the best in the early-strength agents, the water absorption reduced from 0.155 to 0.106, the softening coefficient growthed from 0.46 to 0.90, the wet-dry strength coefficient growthed from 0.725 to 0.885.The paper takes orthogonal table for agents orthogonal optimization test. When the CaCl2 is 6%, FeCl3 is 3%, Al2(SO4)3 is 4%, PVAc is 5%, the property is best. This group of specimens of the compressive strength is 14.11MPa, the softening coefficient is 0.955, the wet-dry strength coefficient is 0.928. That achieves the requirement of wall materials, and realizes the purpose of using cement base biomass materials as building materials.