G MS THESIS_final version_Maxim Prokudin.pdf - Digital Repository ...

66Each being similar in design, except for the shape of the tamping surface, the cone, truncatedcone and flat beveled heads were all 66 mm in diameter and were made out of ANSI 4140hardened steel. While multiple design beveled heads were available for testing, the focus wasmade on utilizing the conventional aggregate pier truncated beveled head and cone shapeheads for most applications in this research. The design drawing for the aggregate piertruncated head is provided in Figure 34.A convenient process of attaching beveled heads to the steel rod was developed, where everybeveled head was attached to the rod by means of a Cleves pin. Thus, having the hammerdrill to be connected to the extended steel rod which in its turn was connected to the scaledsize beveled head, made it possible to easily reproduce the aggregate pier compactionapparatus.Cement MixesWhile most of the aggregate pier and loess pier mixes were compacted using the hammerdrill in even size lifts, the cement mixes were simply delivered to the bottom of the cavity bypouring down the hole and allowing the mixture to cast in place. The mixtures were tampedwith a steel rod to allow the entrapped air to be released.MAKECAVITYPOUR MIX IN VIBRATE TO COMPLETECAVITY ELIMINATE COLUMNTRAPPEDAIRFigure 35: Cementitious pier installation process