Study On Mechanics And Durability Of Modified Bamboo Concrete

With the advancement of building energy conservation and the introduction of green building materials,bamboo as an environmentally friendly material has once again entered the field of vision of domestic and foreign scholars.However,natural bamboo has the shortcomings of being easy to absorb water,easy to decay,and poor adhesion to concrete.These shortcomings limit the development of bamboo concrete.Based on the existing research results,this paper proposes a new method of bamboo modification to overcome its own shortcomings and apply the modified bamboo to concrete for mechanics and durability research.The main work content is as follows:(1)Aiming at the problem that natural bamboo is easy to absorb water,decay,and has poor adhesion to concrete,a modified treatment method of coating the surface of natural bamboo with epoxy resin and spreading 16 mesh emery is proposed.Through compressive test,tensile test,pull-out test,swelling test and density test,the mechanical properties of bamboo before and after modification were studied.Research shows that compared with natural bamboo,the compressive strength of modified bamboo is increased by 17%,the tensile strength is increased by 39%,and the bonding strength with concrete is increased by 109%.The waterproof and anti-corrosion ability is also significantly improved.Good application in concrete.(2)Aiming at the shortcomings of poor concrete tensile properties,the modified bamboo materials are applied to concrete to improve the tensile properties of concrete.Taking concrete strength,protective layer thickness,modified bamboo spacing and modified bamboo quantity as variables,the influence of four variables on the flexural performance and splitting tensile performance of modified bamboo concrete was studied.And get the best combination of modified bamboo and concrete.Studies have shown that the increase in concrete strength and the increase in the number of modified bamboo materials can greatly increase the bending and splitting tensile strength of the modified bamboo concrete.The increase in the thickness of the protective layer and the increase in the distance between the modified bamboo materials have an effect on the modified bamboo concrete.The improvement of flexural and splitting tensile properties is not obvious,but the damage degree of modified bamboo concrete can be improved.The optimal combination of modified bamboo and concrete is: concrete strength is 42 Mpa,protective layer thickness is 20 mm,modified bamboo spacing is15 mm,and the number of modified bamboos is 4.(3)Based on the freeze-thaw failure mechanism,analyze the influence of different concentrations of Na Cl solution(3% Na Cl,5% Na Cl and 10% Na Cl solution)on the degradation law of modified bamboo concrete under the effect of freeze-thaw.Research shows that after 300 freezing cycles of salt,the modified bamboo concrete eroded the most in 5% Na Cl solution,with a mass loss rate of 3.62% and a relative dynamic elastic modulus of 33.8%.Continue to increase the concentration of the Na Cl solution,and the degree of erosion of the modified bamboo concrete will decrease.(4)Based on the sulfate corrosion resistance mechanism of concrete,the durability of modified bamboo concrete was studied.Research shows that: in 10% sodium sulfate solution,after 80 dry and wet cycles,compared with plain concrete,the mass loss and compressive strength loss of modified bamboo concrete are reduced by 50%.The addition of modified bamboo can improve the sulfate resistance of concrete.Through the research of this article,we can overcome the shortcomings of natural bamboo and improve the mechanical properties of natural bamboo.The modified bamboo material is applied to concrete,and the durability test proves that the modified bamboo material concrete has good durability.Modified bamboo concrete is a kind of green environmental protection material,which can be well applied in the construction of low-rise houses and rural houses in our country,and can also be used as a high-quality pavement material.Modified bamboo concrete is of great significance to promote the development of green concrete.