International Concrete Abstracts Portal

The knowledge of dissolution processes of aggregates and supplementary cementing materials (SCMs) in alkaline solutions can help to describe the expansion of concretes caused by alkali-silica reaction (ASR) and the effects to avoid ASR by using SCMs in more details. Therefore, dissolution experiments in alkaline solutions under different pH values and different temperatures were performed using aggregates in the original grain size and SCMs in different ratios. The concentrations of soluble silica and additionally alumina were determined by ICP-OES. The investigations showed that up to now the “best” conditions to explain the damage behavior of concrete structures are a pH value of 13 (e.g. 0.1 M KOH solution) and a temperature of 80 °C. The evaluation bases on the parameter “excess silica” which is calculated from the dissolved silica and alumina of the aggregates and the SCMs. It was demonstrated that SCMs reduce and sometimes stop the dissolution of aggregates. The efficiency of the SCMs depends on their amount and chemical composition.

Editors: V. Mohan Malhotra, Pawan R. Gupta, Terence C. Holland

The Canada Center for Mineral and Energy Technology (CANMET) of Natural Resources of Canada, Ottawa, has played a significant role for more than 40 years in the broad area of concrete technology in Canada. In recent years CANMET has become increasingly involved in research and development dealing with the supplementary cementing materials, high-performance normal weigh and lightweight concretes, and alkali-aggregate reactions. As part of CANMET’s technology transfer program, an international symposium on Advances in Concrete Technology was sponsored jointly with the American Concrete Institute (ACI) and other organizations in Athens, Greece, May 1992. In June 1995 CANMET, in Association with ACI and other organizations in Canada and the U.S., sponsored the Second CANMET/ACI International Symposium on Advances in Concrete Technology in Las Vegas, Nevada. For the Athens symposium, the CANMET publication, “Advances in Concrete Technology,” constituted the proceedings of the symposium. Proceedings from the Las Vegas symposium were published by ACI as SP-154.

In August 1997, CANMET, in association with ACI and other organizations in Canada and New Zealand, sponsored the Third CANMET/ACI International Symposium on Advances in Concrete Technology in Auckland, New Zealand. The main purpose of the symposium was to bring together representatives from industry, universities, and government agencies to present the latest information in concrete technology, and to explore research and development. Thirty-three refereed papers from 15 countries were presented and distributed at the symposium. Proceedings were published as ACI SP-171.

In June 1998, CANMET, in association with ACI, Japan Concrete Institute (JCI), and several other organizations in Canada and Japan, sponsored the Fourth CANMET/ACI International Conference on Recent Advances in Concrete Technology in Tokushima, Japan. More than 80 papers from 20 countries were received and reviewed in accordance with the policies of ACI. Sixty-one refereed papers were accepted for presentation at the conference and for publication as ACI SP-179. In addition to the refereed papers, more than 30 more papers were presented and distributed at the symposium. In July-August 2001, CANMET, in association with ACI and several organizations in Singapore, sponsored the Fifth CANMET/ACI International Conference on Recent Advances in Concrete Technology in Singapore. More than 100 papers from more than 25 countries were received and reviewed in accordance with the policies of ACI. Forty-six refereed and more than 25 additional papers were accepted for presentation at the conference and published as ACI SP-200. In June 2003 CANMET, in association with ACI and several organizations in Romania, sponsored the Sixth CANMET/ACI International Conference on Recent Advances in Concrete Technology in Bucharest, Romania. More than 40 papers presented at the conference were distributed “as received,” and no formal ACI special publication was published.

In May 2004, CANMET, in association with ACI and several organizations in the U.S., sponsored the Seventh CANMET/ACI International Conference on Recent Advances in Concrete Technology in Las Vegas, Nevada. Seventeen refereed papers from more than 10 countries were presented and distributed at the conference. The proceedings, consisting of refereed papers, were published as ACI SP-222. In addition to the refereed papers, 20 additional papers were presented and distributed at the conference.

In May 2006, CANMET, in association with ACI and several organizations in Canada and the U.S., sponsored the Eighth CANMET/ACI International Conference on Recent Advances in Concrete Technology in Montreal, Canada. Proceedings of the conference, consisting of 17 refereed papers, were published as ACI SP-235. In addition to the refereed papers, more than 30 additional papers were presented and distributed at the conference.

In May 2007, CANMET, in association with ACI and several organizations in Canada, Europe, and the U.S., sponsored the Ninth CANMET/ACI International Conference on Recent Advances in Concrete Technology in Warsaw, Poland. Proceedings of the conference consisted of 10 refereed papers that were published as ACI SP-243. More than 20 additional papers were presented and distributed at the conference. In October 2009, ACI, in association with several organizations in Canada, Europe and the U.S., sponsored the Tenth ACI International Conference on Advances in Concrete Technology in Seville, Spain. Proceedings of the conference consisting of 20 refereed papers that were published as ACI SP-261. In addition to the refereed papers, more than 20 additional papers were presented at the conference and published in a Supplementary Papers Volume.

In May 2010, the Committee for the Organization of International Conferences (COIC) (formerly CANMET/ACI Conferences), in association with the Chinese Ceramics Society (CCS) and several other organizations in China, sponsored the Eleventh International Conference on Advances in Concrete Technology and Sustainability Issues in Jinan, China. More than 40 papers were presented at the conference. The proceedings of the conference were published by the (CCS), Beijing, China.

In October 2012, the COIC, in association with ACI, sponsored the Twelfth International Conference on Advances in Concrete Technology and Sustainability Issues in Prague, Czech Republic. The proceedings of the conference consisted of more than 30 refereed papers that were published as SP-288. In addition to the refereed papers, more than 40 other papers were presented at the conference and were published in the Supplementary Papers Volume.

In July 2015, the (COIC), in association with the ACI sponsored the Thirteenth International Conference on Advances in Concrete Technology and Sustainability Issues in Ottawa, Canada. The proceedings of the conference consisting of 28 refereed papers were published by the ACI as SP-303. In addition to the refereed papers, more than 40 other papers were presented at the conference and were published in the Supplementary Papers Volume.

Many thanks are extended to the members of the Technical Paper Review Panel who met in Bahamas in October 3 to 11, 2014 to review the papers. Without their dedicated efforts, it would not have been possible to publish the proceedings for distribution at the conference. The cooperation of the authors in accepting the reviewers’ suggestions and in revising the manuscripts accordingly is greatly appreciated.

The help and assistance of Dr. Pawan R. Gupta and Prabha Gupta are gratefully acknowledged in the administrative work associated with the conference, and processing of the manuscripts for both the ACI proceedings (SP-303) and the Supplementary Papers Volume.

Note: The individual papers are also available. Please click on the following link to view the papers available, or call 248.848.3800 to order. SP-303

Calcium sulphoaluminate cements (CSA) may provide an eco-friendly alternative to ordinary portland cement (OPC). These cements have been widely used in the past, alone or in combination with OPC, because of their well-known rapid hardening and shrinkage-compensating behavior. CSA cements are characterized by a lower environmental impact than OPC, thanks to a different raw material mixture and a lower energy demand associated to the production process. In this study, the mechanical and the durability characteristics have been investigated, according to the European standards, both for CSA-OPC blends and pure CSA containing concretes. Tests have been carried out using different OPC sources and blending percentages, starting from a 85/15 OPC/CSA blend to a 100% CSA cement. The concretes performances have been compared to reference concretes made with only OPC, the tests included slump retention, compressive strength, drying shrinkage, resistance to freezing and thawing and resistance to chloride penetration. A satisfactory behavior has been observed, especially for the 70/30 OPC/CSA blend, which showed good performances in all the tests.

The effect of initial steam curing and different types of mineral additives (Metakolin, Pumis, and Trass) on mechanical and durability characteristics of self-compacting concrete (SCC) was investigated and evaluated by various test methods. Concrete specimens were exposed to six different steam curing regimes after casting, namely two different temperatures (60, and 70 °C), and three total durations (16, 18, 20 hours). Results of surface electrical resistivity, and Rapid chloride penetration test (RCPT) for durability, and compressive strength for mechanical properties showed that exposing specimens to higher temperature could significantly improve compressive strength by promoting hydration.

While the cement industry is currently working on a number of initiatives to reduce CO2 associated with cement production (i.e. thermal and electrical efficiency, alternative fuels and clinker substitution) a significant CO2 mitigation is still desired and will require novel solutions. The reaction of carbon dioxide with hydrating cement is known to produce stable carbonate reaction products. These reactions can serve to effectively bind CO2 in the cement matrix during the fresh state while offering material benefits. Carbonation treatments have been integrated into industrial concrete production. Producers can sequester carbon dioxide in their products and more favorably position concrete in a competitive green building product marketplace. The case studies examine the application of carbon dioxide to concrete masonry production (strength, absorption and density) and ready-mix concrete production (workability, strength). The carbon dioxide integration has minimal impact on conventional process operations and works with existing production equipment. Estimates of the net environmental impact are made.