コンクリートの打設・締固めにおける加圧成形の曲げ挙動に及ぼす影響について

抄録

Fiber reinforced concrete contains a large amount of short fibers randomly dispersed into cement concrete and this composite material is superior to normal plain concrete with respect to its flexural strength, impact resistance and ductility. But the consistency of concrete is extremely decreased by adding fibers so that in some cases it becomes difficult to place and mold by the ordinary method. These phenomena are observed irrespective of kinds of fibers used.
In this paper, the effects of compaction methods on the strength of fiber reinforced concretes having poor consistency and containing a fairly large amount of fibers were investigated·Conventional steel fibers and alkali-resistant glass fibers were used.
Test specimens (10×10×60cm) of plain and fiber reinforced concretes were compacted by external vibration with temporary or continuous compressive loading, and were tested in flexure. The mechanism of compaction effects was discussed.
The test results indicate that the compaction with compressive loading increases the flexural strength of both types of fiber reinforced concretes as well as the extensibility of glass fiber reinforced concrete although the improvement is made within a certain limit of compaction loading.