Papers by Keyword: Testing Research

Abstract: In this paper, through the experimental study about the stress of soil around the pile when the bearing push-extend reamed have different diameters, observed the destruction of soil around the pile. Further determined the destruction of soil form, verify the theoretical analysis results of the influence for bearing capacity of the push-extend Multi-under-reamed pile in the different diameter of the bearing push-extend reamed. It provided a reliable basis of comprehensive considering the factors influencing of the Push-extend Multi-under-reamed Pile in the actual design.

Abstract: As high strength concrete (HSC) is widely used in construction, more and more attention has been paid to crack resistance of it. In order to improve crack resistance of HSC, we study the influence of mineral admixtures (ground slag, silica fume and fly ash) on brittleness and characteristic length as crack resistance’ indexes. Testing researches shows, without admixture, crack resistance of HSC is the lowest; when one of the three mineral admixtures added, crack resistance increases dramatically; when two of the three mineral admixtures are added in the concrete, crack resistance increases a little more and it does not change very much no matter which two are mixed; crack resistance comes out the highest when the three mineral admixtures are added in concrete. Mechanism analysis shows, Adding fine and high active ground slag, silica fume and fly ash into concrete can greatly improve microstructure of transition zone, decrease Ca(OH)2, ettringite and porosity in concrete, increase C-S-H gel and greatly reduce the original micro-cracks in the transition zone.