Title:
New Prediction Methods of Durability Application to Concrete with and Without Fly Ash
Author(s):
S. Alegre, J. A. Lechuga, and J. Perxas
Publication:
Symposium Paper
Volume:
100
Issue:
Appears on pages(s):
681-704
Keywords:
carbonation; chlorides; concrete durability; diffusion; fly ash; permeability; porosity; sulfate resistance; tests; Materials Research
DOI:
10.14359/1921
Date:
4/1/1987
Abstract:
As a consequence of the increasing use of fly ash added to concrete at the plant in Spain, several studies have been developed with the objective of checking the performance of the obtained concretes, especially with respect to its durability. These studies have been more intensely developed in Catalonia, where fly ash from the Cercs Power Station is extensively used in concrete production. Numerical examples given in the paper of concrete with fly ash refer specifically to fly ash from Cercs, which is obtained from lignite-type coal. To check some variables that influence the durability (mechanical resistance, modulus of elasticity, creep of the concrete, etc.), there exist some standard methods that use concrete samples. Nevertheless, to verify other variables, trials are usually done with paste or mortar samples, with which there is the risk that the obtained results are different than what would have been obtained if the sample used had been concrete. That is why, in these studies, new testing methods have been developed using concrete samples and very simple apparatus to measure some characteristics usually tested on pastes and mortars. These methods are briefly summarized in the paper. They measure permeability to liquids, permeability to gas, liquid absorption, carbonation tests, diffusion of chloride ion, and resistance to sulfate attack. Finally, it is verified that the durability of the reinforcements within the tested concrete would be foreseeable with the indicated tests, as measurements made with the resistance to polarization technique give concordant results with those deduced from the previously mentioned new tests.