Study On Capillary Absorption And Transmission Characteristics Of Cement-based Material Using Electrical Method

Concrete was considered a engineering materials with good durability. But due to the diversification of environment in recent years, the premature failure of concrete structure brings great damage to personal property security. All around the world are faced with the problem. Therefore solving the problem, the durability of the concrete structure and service life has become the most important issue in the field of civil engineering today. It is worth noting that the external corrosive substances or ion needing the water as medium or following the pores, cracks the pore or franture in concrete to the interior structure. In addition to having the effect of handling erosion material, moisture migration also leads to changes in the effective stress of concrete and the difference of internal water saturation. It has a great influence on the speed and degree of various damage.Therefore, the mainly research work of this article are as follows:(1) Studying some factors such as the aggregate content、water cement ratio and ages without the influence of aggregate and salt solution as a transport medium have the influence on capillary absorption of concrete, providing theoretical basis for appraising of the durability of concrete structure. Minimize the degree of damage such as Cl-、SO42-plasma erosion which are closely related to water transport.(2) By studying on the electrical performance of cement-based material through experiments, determine the suitable curing age to study the electrical property of cement-based material. Using plate electrode, jugde humidity front-end transmission in the process of water transport process, and prove that water and ion transmission mechanism is different in the process of transmission, rate of sync, and have mutual effect between them. Then it’s different for the electrical performance influence degree between the chloride ion and pore solution. Electrical performance can reflecte the change of moisture content and ion concentration.(3) The test electrode was improved by the use of special needle electrode, then tested internal moisture transmission and distribution of the cement-based material. The testing apparatus is simple, easy to optimization. After optimization it can be used as a practical engineering health monitoring method. In addition, combined electrical performance test method and weighting method can be used to analysis the porosity parameters. It had important guiding significance for evaluation of material shrinkage and other related characters to the porosity.