Effect of the storage conditions of cement on the processing and hardening properties of concrete
Interruptions in production in concrete plants can lead to significant storage intervals. On construction sites and in repair, bagged cement and dry mortar are sometimes stored for longer periods of time. The relevance of cement storage increases also for imported cement and the more and more finely adjusted concrete mix designs that can already react sensitively to slight changes in the initial constituents. For this reason, the influence of cement storage on the properties of concretes was determined in a series of tests conducted at the German Federal Institute for Materials Research and Testing (BAM).
Motivation for the investigations The stability and/or the effects of storage length and storage conditions on the efficiency of cement in mortars and concrete has been investigated for many years under the aspect of quality assurance. Here, however, the achieved strength is typically taken as reference benchmark. In 2002, the cement building consultancy Bauberatung Zement formulated in a code of practice that the storage capability of cement is unlimited, provided ingress of moisture is prevented. It further states that when cement is suitably stored in a silo or paper bags, a loss of...