The Research On Concrete Permeability And Test Methods On The Concrete Permeability

For concrete structure in the practical engineering, the non-mechanics damage, are unavoidable due to the existence of erosive media. The deterioration form of mono or multi-factor influences on the concrete property of construction and durability greatly, and shortens the service life of the concrete to a large extent. Permeability of concrete is the most important factor for these non-mechanics damages, so the permeability test of concrete is the normal and required item to study the durability of concrete. GBJ 82-85 are applied less due to the long test period, heavy and lower efficiency respectively, can't measure the on-the-spot concrete, it compare and analyse different this text water dust than, fly ash mixing amounts different and mixing by water-reducing agent impact on concrete permeabilities high-efficient, further compare and analyse the france's pluses and minuses of national standard law, relative permeability coefficient law, direct current amount and applicable scope, offer the data for experiment method standard formulation of national durability through studying.The result of study indicates, mix the concrete of high-efficient water-reducing agent, because water-reducing agent one reduces water, disperses function, and has reduced the hole of the concrete and change hole structure, has caused the total space rate of concrete to reduce, closely knit degree is greatly improved, the impervious performance of concrete is obviously improved; mix the impervious performance that the fly ash can obviously improve the concrete too, and water result and detailed particle that does not react that react pack cement hair of stone detailed and empty because of fly ash mainly, have improved the empty structure of the concrete, make the concrete more closely knit, has improved impervious performance.Pass the test result to compare with analysis indicating. Have very good relevance as to the law of coefficient and impervious law of national standard, its coefficient correlation is 0.9776, compared with national standard, raise the efficiency, has overcome a lot of weak points in national standard law. Have imitated the infiltration situation in reality more truly as to the law of permeability coefficient, and is lower than C30 by concrete ASTM C1202 laws to the intensity and actual infiltration relevance is relatively bad.Finally, we studied the effect of compression grade to coefficient of permeability in this paper, the results show that the permeability coefficient under examining different pressures of the same concrete with the relative coefficient law, 0.8MPa, 1.2MPa two kinds of pressure relevance are very good, and 2.0MPa has obvious deviations, prove the relative permeability coefficient formula is to having non-applicable for 2.0MPa pressure.