ABOUT THE INTERNATIONAL CONCRETE ABSTRACTS PORTAL

  • The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.

International Concrete Abstracts Portal

  


Title: Evaluation of In-Place Stress in Concrete by Incremental Hole Drilling

Author(s): Ashutosh G. Dabli, Abhay N. Bambole, and Kamalkishor M. Bajoria

Publication: Materials Journal

Volume: 117

Issue: 4

Appears on pages(s): 27-35

Keywords: finite element method; in-place stress; incremental hole drilling method; nondestructive testing; strain relief

Date: 7/1/2020

Abstract:
The use of strain relief method is one of the most direct methods for determination of in-place stresses. In this method, a hole is drilled in the concrete member and the change in strain in the vicinity of the hole, on the surface of the member, is measured by means of electrical resistance strain gauges (ERSG). This change in strain due to drilling is used to assess the in-place stress in the member using constitutive relationship and calibration coefficient. This paper presents the experimental application of incremental hole drilling method (IHDM) in concrete under uniaxial stress. A small hole of 25 mm diameter and 40 mm deep was drilled incrementally to estimate the in-place stress in an axially loaded column with minimum damage. Dry drilling was used to eliminate the effect of swelling due to moisture (water) during the drilling. The experimental strain released was then correlated with an analytical solution using the theory of elasticity and finite element method (FEM). The excellent agreement of experimental results with analytical and numerical values of strain released suggests that IHDM can be conveniently used to evaluate in-place stresses in columns.




  

Please enter this 5 digit unlock code on the web page.