Studying On Freezing-Thawing Resisting Durability Of The Frame Concrete

Based on the "Big Center Nature"theory which is created by Academician Wu Zhongwei and professor Lian Huizhen and referring to stacking theory,the concrete frame and structure model and theoretic frame of designing of frame and construct concrete were put forward by professor Wang Lijiu of Dalian university of technology and finish mainly by Cao Mingli. The author believed that the concrete was composed of coarse aggregate frame and structure, glue sand and interface transition area.The theory could open out the essence of concrete microscopical structure,it will embody more adequately how much every ingredient in concrete has contributed to the integrated performance of concrete in real sense.This model breaks a new path in the field of research into concrete and lays a solid academic foundation for concrete's digital design.This paper mainly base on the concrete frame and structure model,according to fracture mechanics,establish the frostbiting principle based on cracking load;at the same time,study the frost resistance and permeability resistance of the frame concrete.;establish the freeze thawing decreasing model based on impermeability lost rate;we put forward the effect-embolism of mini-powder based on the effect in concrete,It can be used for implement the quantificational constituting durability of High Performance Concrete.This thesis mainly includes some parts:Firstly,establish the frostbiting principle based on cracking load,and put forward the new evaluate method of the freezing resistance.Based on many experiments,the factors of the concrete cracking load have been discussed.And the measure of improving the frost resistance have been put forwarded.Secondly,the frost resistance of the frame concrete has been studied,analyzing the relationship of frost resistance between aggregate/mortar ratio,blending composition, cracking load.Thirdly,using electric field to simulate the seepage,the permeability resistance is putted forward according to the correlation between the seepage and electric field,and using alternating current survey the permeability resistance of the concrete.Analyzing the relationship of Permeability between water/binder ratio,blending composition,concrete strength. Forthly,the relation between frost resistance and permeability resistance of the frame concrete have been studied according to many experience.Due to sensibility of permeability when concrete has been freezed.Using the permeability of the concrete represent the freezing level of concrete,the freeze thawing decreasing model based on impermeability lost rate established.Predicting the service life of the concrete based on the freeze thawing decreasing modelFinally,the author put forward the action mechanism of Mineral mini-powder: effect-embolism,and also use the modulus-embolism to exact show how many they can improve the durability of Concrete,namely the size effect of embolism.It can be used for implement the quantificational constituting durability of Concrete.