Experimental Study On The Mechanical Property Of High Ductility Cementitious Composites

Concrete material is currently the most widely applied to engineering, directimpact on project safety, economy and durability. Concrete is a kind of mixture ofcement, sand, stone and other basic raw materials.The materials are non-renewableresources, which are having a profound impact on the environment and ecology.Concrete itself is deficient, low tensile strength, brittleness, ultimate elongation, andimpact resistance is poor. In order to improve these defects in the concrete, fiberreinforced concrete emerged. PVA-Engineered Cementitious Composite is a hightensile strain, and has a significant strain hardening performance and multiple cracking.PVA-ECC materials used in engineering structures can obviously improve the seismicperformance and durability of the structure. PVA-ECC make full use of industrialwaste, such as fly ash, slag, which is important for the conservation of resources,energy, and the ecological environment. PVA-ECC can be called “new greenengineering materials”. This article is mainly from the following aspects of thematerial’s basic properties to start the study:（1）Research on ECC uniaxial tensile test. A uniaxial tensile test is carried outusing the improved tensile test apparatus PVA-ECC specimen，obtaining tensilestress-strain curve. The ultimate tensile strain is about1.19%. Tests of uniaxial tensileproperties show the partial PVA-ECC possess multiple cracking characteristics andstrain-hardening properties. Analysis of the water-cement ratio, fiber content, fly ashcontent and sand binder ratio effect on the ECC tensile strength, ultimate strength andultimate tensile strain.（2）Research on water binder ratio, fiber content by volume, fly ash content andsand binder ratio4kinds of factors effect on the ECC materials compressive and flexural strength. The results showed that: the content of fly ash and water-cementratio is the main factor affecting the PVA-ECC compressive strength; fiber content byvolume is a main factor affecting the PVA-ECC flexural strength.（3）Through the different mixture ratio, the test block of the different sizes tostudy PVA-ECC cube compressive strength. Test results show that: The smaller thesize of the specimen, the higher the compressive strength.Compression test carried outby the different size cube prism, contrast cube the prism specimens compressiontesting results, analyzes the relationship of the strength of the specimen, and thecorresponding relationship formula is obtained by linear fitting.