Location
the Sixth International Conference on Durability of Concrete Structures (ICDCS 2018) which will be held in Leeds, UK
Event Website
https://engineering.leeds.ac.uk/icdcs2018/
Keywords
Alkali-Silica Reaction, ASR-resistant concrete mix, Concrete durability
Abstract
The main objective of this study was to develop rapid aggregate and concrete test methods and a combined innovative approach for formulating performance based ASR resistant concrete mixes. An innovative step by step approach has been developed to formulate ASR resistant concrete mixes based on four recommended steps. In step 1, determination of aggregate ASR composite activation energy (CAE) and threshold alkalinity (THA) by using a rapid aggregate chemical test called volumetric change measuring device (VCMD) is performed. The lower the CAE the higher the reactivity is. Based on the measured CAE and THA, mix design formulation is conducted in step 2 by applying mix design controls and special protection measures. In step 3, verification and adjustment of the mix developed in step 2 is performed based on THA and pore solution alkalinity (PSA) relationship - PSA needs to be below THA in order to prevent/minimize ASR. Mix design validation by using a newly developed accelerated concrete cylinder test (ACCT) is a part of step 4. Job concrete mixes made of aggregates with different levels of ASR reactivity were tested using the above approach with the four steps. The CAE-based method shows better correlation with ASTM C1293 than ASTM C1260 and was found to be effective to consistently identify the aggregates belong to false positive (i.e., failed by C1260 but passed by C1293) and negative (passed by C1260 but failed by C1293) categories. The proposed approach has the ability to rapidly assess the ASR potential of each aggregate at various alkali loadings and tailoring mix design depending on the level of protection needed.
Final revised paper
Responses-for-the-reviewer's comments.pdf (178 kB)
Responses to the reviewer's comments
ICDCS2018_paper_Emerging_ASR_test_methods_ASR_resistant_mixes_KL_AKM_USA_Revised-final.pdf (681 kB)
Revised paper along with the responses for the reviewer's comments
Included in
Emerging Rapid Aggregate and Concrete Test Methods for Formulating Asr-Resistant Concrete
the Sixth International Conference on Durability of Concrete Structures (ICDCS 2018) which will be held in Leeds, UK
The main objective of this study was to develop rapid aggregate and concrete test methods and a combined innovative approach for formulating performance based ASR resistant concrete mixes. An innovative step by step approach has been developed to formulate ASR resistant concrete mixes based on four recommended steps. In step 1, determination of aggregate ASR composite activation energy (CAE) and threshold alkalinity (THA) by using a rapid aggregate chemical test called volumetric change measuring device (VCMD) is performed. The lower the CAE the higher the reactivity is. Based on the measured CAE and THA, mix design formulation is conducted in step 2 by applying mix design controls and special protection measures. In step 3, verification and adjustment of the mix developed in step 2 is performed based on THA and pore solution alkalinity (PSA) relationship - PSA needs to be below THA in order to prevent/minimize ASR. Mix design validation by using a newly developed accelerated concrete cylinder test (ACCT) is a part of step 4. Job concrete mixes made of aggregates with different levels of ASR reactivity were tested using the above approach with the four steps. The CAE-based method shows better correlation with ASTM C1293 than ASTM C1260 and was found to be effective to consistently identify the aggregates belong to false positive (i.e., failed by C1260 but passed by C1293) and negative (passed by C1260 but failed by C1293) categories. The proposed approach has the ability to rapidly assess the ASR potential of each aggregate at various alkali loadings and tailoring mix design depending on the level of protection needed.
https://docs.lib.purdue.edu/icdcs/2018/pse/14
