Study On The Performance Of The Ecological Cementing Material And Concrete

Modern concrete is multicomponent concrete developed on the basis of wide application in the chemical additive technology, there has been a fundamental change compared with traditional concrete. One of the important aspect is the change of the demand for cementing material. At present, the proportion of highly active material is greatly reduced than the past when the active development of cementing material is strongly depended on, and allows a certain percentage of non reactive powder.As cement industry wants to develop in the direction of Portland cement production, there is a need to develop a series of new cementing material which can meet the needs of the concrete engineering, among which the low clinker cement materials is the research object of this project. This paper puts forward the concept of ecological cementing material, namely, the cement clinker and mineral admixture need to be respectively grinded, and adding organic or inorganic performance regulator in the process of grinding, Optimizing the content of gypsum, and then produce the cementing material by the homogenization according to a certain proportion after grinding(mineral admixture is greater than 50%).There is a need to develop different types of ecological cementing materials to match different performance requirements of concrete, and promote concrete technology and industry on a sustainable path.Through the ecological cementing paste and mortar performance test, determine the suitable content of SO3, then compare the workability, mechanical properties and durability of the concrete which made by ecological cementing materials and cement + admixture under the same condition and components, to determine the proportion of each auxiliary cementing materials in the ecological cementing materials, and to analyze the microstructure.Experiment shows that, the water demand behavior of ecological cementing materials is good, initial setting and final setting time are both higher than the ordinary cement, and meet the requirements of the national standard. A moderate amount of mixing with limestone powder can improve the early strength of mortar of ecological cementing material. When the slump of concrete is ranging from 210±10mm, the adding of ecological cementing materials can reduce the water consumption of concrete, the water to binder ratio can be 0.02 smaller than cement concrete control group. In order to improve early strength of concrete made by ecological cementing materials, it is recommended to use Ⅲ performance regulator. The C25, C30 ecological cementing materials appropriately choose Ⅲ performance regulator, C50 ecological cementing materials is not recommended. The concrete made by ecological cementing materials has good strength development rule: early strength is slightly lower, but it can meet the demand of concrete, the late strength continued to grow, 180 d strength has been 5 ~ 10 MPa more than the control group strength. Ecological cementing materials has good crack resistance and shrinkage performance, and it does not affect its resistance to chloride ion penetration and carbonation resistance, the cracking time is late in the ring crack test of ecological cementing materials, and the width of fracture is small. The microscopic study of C30 concrete shows that, type Ⅲ performance regulator can reduce the internal pore of the concrete, ecological cementing materials still have a certain amount of hydration of cement particles and large amount of admixture, which guarantee for the later strength increasing. At the same time, the test shows that the durability of concrete made by ecological cementing materials is trustworthy.