The Study Of Graphite Conductive Aggregate Preparation And Its Cement-based Composites Preparation

Conductive concrete is an important direction of concrete functionalize, and it plays an important role and has a broad application in engineering structures intellectualization, road ice melting and electromagnetic shielding of buildings, etc. Material types of conducting phase and its distribution affect electrical conductivity and mechanics properties of conductive concrete greatly. Aiming at the solving the problem of obstruct of the existing concrete aggregate on conduction network integrity and continuity, this paper depends on the national natural science funds, conducts the preparation of graphite conductive function aggregates, cement-based conductive function material and their performance research, and the main research work and achievements are as follows:The preparation method of graphite conductive function aggregates is proposed. Orthogonal experimental method is utilized, and clay is used as pottery basis material, graphite powder as the main conductive component. The performance test are carried out for the samples with different graphite contents and various calcination regimes. The optimal graphite content calcinations regimes are determined and conductive function aggregates with excellent electrical conductivity are prepared.Preparation method of conductive function aggregate-carbon fiber multi-phases conductive cement-based material is proposed. The effects of conductive function aggregate content, carbon fiber content and dispersion manner, curing age and free water content on the properties of conductive cement-based material are studied. And the best proportion and preparation process parameters of conductive cement-based material whose main conductive phase are conductive function aggregates and carbon fiber are proposed.Conductive mechanism of conductive function aggregate-carbon fiber multi-phases conductive cement-based material is proposed. The microstructure of multi-phases conductive cement-based material is analyzed by means of SEM, polarizing microscope, etc. Combined with electrical performance tests, it is proposed that conductive passway effect, tunneling effect and electric field emission effect together result in the conductive mechanism of conductive function aggregate carbon fiber cement-based complex phase conductive material.The excellent pressure-sensitive characteristics of conductive function aggregate-carbon fiber multi-phases conductive cement-based material are proved. With the cyclic loading experiments, the resistance changes of conductive function aggregate-carbon fiber multi-phases conductive cement-based material under different stress levels, loading rates, carbon admixture and conductive function aggregate content, etc. are discussed.