Selection of Thermal Integrity Data Regression Parameters

Abstract

Abstract Thermal integrity profiling (TIP) is a nondestructive method of evaluating the as-built features of cast-in-place concrete foundation elements such as bored piles, drilled shafts, continuous flight auger piles, barrettes, dams, or diaphragm walls. The technology measures the temperature of curing concrete along the length of the element to detect the presence (or absence) of hydrating cement, alignment of the reinforcing steel, and rebar cover thickness. Like many integrity methods used for drilled shafts, direct comparison of local concrete conditions are made relative to the overall normal or average concrete conditions with two exceptions: the top and bottom of the element, which cannot be directly compared with the rest of the shaft temperature without adjusting those measurements to account for end effects. This paper outlines the selection of the end adjustment parameters to ensure the top and bottom shapes are properly defined. The presented data regression process is based on both numerical model findings as well as the statistical findings from 232 TIP-tested shafts on the same project.