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OTREC RR-13-01 By Jennifer Tanner et al.
eBook (PDF): $0.00
This Phase II investigation of the durability of new concrete containing recycled concrete aggregates (RCA) sought to corroborate Phase I results for a study of alkali-silica reactivity (ASR),... More > investigate ASR mitigation methods, gather long-term outdoor placement data, and survey transportation agencies about their RCA perceptions and usage. Findings show the ASTM coefficient of variation limits do not apply when incorporating RCA. We recommend further testing to establish new standards. The survey showed sustainability was important to most agencies; 54% had guidance for RCA use in new concrete, but only 15% reported strong federal guidance; 77% had concerns about ASR reaction; the biggest barriers to RCA use were quality issues, lack of standards, and unclear test guidance; the biggest RCA source concerns were shrinkage, ASR and residual chlorides. Data sought on RCA sources were condition at removal from service, reason for removal, whether the original structure needed repairs, and material age.< Less
OTREC RR-13-01 By Jennifer Tanner et al.
Paperback: $4.70
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This Phase II investigation of the durability of new concrete containing recycled concrete aggregates (RCA) sought to corroborate Phase I results for a study of alkali-silica reactivity (ASR),... More > investigate ASR mitigation methods, gather long-term outdoor placement data, and survey transportation agencies about their RCA perceptions and usage. Findings show the ASTM coefficient of variation limits do not apply when incorporating RCA. We recommend further testing to establish new standards. The survey showed sustainability was important to most agencies; 54% had guidance for RCA use in new concrete, but only 15% reported strong federal guidance; 77% had concerns about ASR reaction; the biggest barriers to RCA use were quality issues, lack of standards, and unclear test guidance; the biggest RCA source concerns were shrinkage, ASR and residual chlorides. Data sought on RCA sources were condition at removal from service, reason for removal, whether the original structure needed repairs, and material age.< Less
OTREC-RR-13-01 By Jennifer Tanner et al.
Paperback: List Price: $9.50 $7.13 | You Save: 25%
Prints in 3-5 business days
This Phase II investigation of the durability of new concrete containing recycled concrete aggregates (RCA) sought to corroborate Phase I results for a study of alkali-silica reactivity (ASR),... More > investigate ASR mitigation methods, gather long-term outdoor placement data, and survey transportation agencies about their RCA perceptions and usage. Findings show the ASTM coefficient of variation limits do not apply when incorporating RCA. We recommend further testing to establish new standards. The survey showed sustainability was important to most agencies; 54% had guidance for RCA use in new concrete, but only 15% reported strong federal guidance; 77% had concerns about ASR reaction; the biggest barriers to RCA use were quality issues, lack of standards, and unclear test guidance; the biggest RCA source concerns were shrinkage, ASR and residual chlorides. Data sought on RCA sources were condition at removal from service, reason for removal, whether the original structure needed repairs, and material age.< Less
OTREC-RR-11-09 By Jennifer Tanner et al.
eBook (PDF): $0.00
The primary goal of this research project was to investigate the long-term durability of concrete incorporating recycled concrete aggregate (RCA) through accelerated laboratory testing. Overall it... More > was found that modifications to standard aggregate testing and characterization standards were necessary for testing RCA. This included modifications to standard tests including ASTM C 128, C 305 and C 1260. It was found that the potential for alkali silica reactivity did exist for new concrete containing RCA. The characteristics of the RCA also had a profound effect on ASR related expansion. RCA with a higher content of reactive coarse or fine aggregate (compared to paste fraction) exhibited greater reaction and would therefore require higher levels of mitigation. Based on testing in this research project precision and bias statements in ASTM C 1260 (for virgin aggregate) do not apply to RCA. Recommendations for future work are also included in this report.< Less
OTREC-RR-11-09 By Jason Ideker et al.
Paperback: $5.38
Prints in 3-5 business days
The primary goal of this research project was to investigate the long-term durability of concrete incorporating recycled concrete aggregate (RCA) through accelerated laboratory testing. Overall it... More > was found that modifications to standard aggregate testing and characterization standards were necessary for testing RCA. This included modifications to standard tests including ASTM C 128, C 305 and C 1260. It was found that the potential for alkalisilica reactivity did exist for new concrete containing RCA. The characteristics of the RCA also had a profound effect on ASR related expansion. RCA with a higher content of reactive coarse or fine aggregate (compared to paste fraction) exhibited greater reaction and would therefore require higher levels of mitigation. Based on testing in this research project precision and bias statements in ASTM C 1260 (for virgin aggregate) do not apply to RCA. Recommendations for future work are also included in this report.< Less

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