| The concrete carbonization is a phenomenon to react hydrate production in the concrete with CO2 in the environment etc. acidity air , which born carbonate or other material and cause concrete neuter .The carbonization will make the inner compose and organizes in the concrete change, and affect the character and enduring of the concrete construction directly. On the base of study of the formers , The text writer carried on the concrete modeling , protecting , the anti- presses strength and fast carbonization experiment according to the《Irrigation Work Concrete Experimentation Rules》DL/T 5150—2001.The paper mainly studied the relations of concrete carbonization depth and W/C, cement dosage, carbonize time, anti- presses strength, the rate of water, environment temperature and humidity, and tested the connection expression on fast carbonization and nature carbonization basing on the experimentation result about fast carbonization and nature carbonization of same sample. According to the trial results, the paper established the average carbonization depth mathematics model of regarding anti- presses strength as the main factor, and the carbonization depth rate distributes model, and validated them in theory and actual engineering data.The paper come to the conclusions according to the experiment1 W/C is an important factor to affect the concrete carbonization depth. If W/C depress, the carbonization depth would recede, the both are linearity.2 On the same W/C, lf cement dosage increase, carbonization depth would reduce, but the influence is not very big. Since the method cannot choose to only increase cement dosage.3 If the rate of water become bigger, the carbonization depth would reduce. To decide the concrete carbonization of the degree is not the relative humidity but concrete wetness state.4 Along with the aggrandizement of the concrete strength, the direction of carbonization depth is reducing .The concrete carbonization depth and anti- the strength is in line, and the relativity is better, but it has suitable scope.5 Carbonization depth would augment if the time prolong , it submit power function relation.6 The climate condition about environment temperature and humidity obviously influence to the carbonization speed, and environment temperature influence in carbonization higher than opposite humidity. If the opposite humidity would be steadiness and environment temperature hoist, Carbonization depth augment; If environment temperature is steadiness and opposite humidity hoist, Carbonization depth would minish.7 According to the stat data of anti- presses strength and the carbonization depth in the actual engineering, The paper make use of minimum two multiplications to curve match, and get the influence coefficient of anti- press strength to carbonization speed.8 The thesis has gotten the function about carbonization depth rate distributes, which obey normal school through examination. The concrete carbonization life span may be estimated, if there are the measuring carbonization depth, the reinforcing steel bar protecting layer thickness and the carbonization eligibility guideline.The paper has three new points on the concrete carbonation test .1 On the theory model about concrete carbonation, the carbonation depth coordinate to carbonation time's square. In the test, time index changed in 0.39~0.52, and whose average is 0.42, the paper think the time index is 0.42, which is highly accurate though theory and engineer verified.2 On the fast carbonization experimenting result, the paper get the influence coefficient of the environment temperature and the opposite humidity to carbonization speed .3 Considering the environment temperature, opposite humidity, the density of CO2, concrete a position, anti-presses strength and carbonization time to the influence of the concrete carbonization depth, the paper put forward the carbonization depth mathematic model .The model is credible and basically suit to practice project by theory analyse and project checking computations.
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