National Driller magazine recently republished a paper by authors from GRL Engineers Inc. and Pile Dynamics Inc. (PDI) describing a demonstration project for the Texas Department of Transportation involving thermal integrity profiling (TIP) of soil nails. TIP involves using the thermal energy created by curing concrete to determine the shape of a grout or concrete body and the position of reinforcement within a grouted or concreted hole. It has been used successfully for QC of drilled shafts and auger cast piles. It can be performed in open access ports by lowering a thermal probe down the hole, or by attaching thermal wire cables to the reinforcement with sensors spaced every 6 inches. This study used the thermal wire cables attached to two soil nail bars grouted into 6 inch diameter holes. The first nail had no deliberate defects, the second had two intentional soil inclusions attached to the bar prior to grouting. The TIP successfully identified the anomalies and it appears that the method shows potential for QC of the shape and diameter of a grout body around a soil nail. [Source: Read the article at National Driller. Image: National Driller]
