Paper by KORSHUNOV from ISCR 8th 1998 Lisbon Portugal
A 7 Lu 8% reduction in compactness of air-entrained concrete with respect to the maximum one is a positive factor from the frost, -salt resistance standpoint, nevertheless, such compactness of roller compacted concrete can lead to dangerous results. The existing methods of controlling the compaction rate (measuring the volume of entrained air in concrete mixes and concrete polished specimens, modified Proctor method, etc.) are imperfect and labour consuming. Investigations of Soyuzdornii made it possible to develop an easy for fulfilment and acceptable for practical use procedure of controlling and assessing the compaction rate of concrete extracted from the structure. The procedure is based on the principle of dividing the total concrete porosity into compaction pores and undercompaction ones (air pores) by the use of saturation method. Knowing a real rate of concrete compaction in the structure, an engineer can take the right decision.