Title: Analysis of In-Place Test Data With Spreadsheet Software

Author(s): Nicholas J. Carino and William C. Stone

Publication: Symposium Paper

Volume: 101

Issue:

Appears on pages(s): 1-26

Keywords: compressive strength; computer programs; concrete construction; microcomputers; pullout tests; safety; statistical analysis.

DOI: 10.14359/3823

Date: 9/1/1987

Abstract:
In-place testing offers the contractor an alternative to testing field-cured cylinders for assessing concrete strength during critical phases of construction. A relationship between cylinder compressive strength and the quantity measured by in-place tests is needed to use these methods; this requires statistical analysis of test data. The personal computer and "electronic spreadsheet" software provide a cost-effective means of performing such analyses. Available spreadsheet software can be used to perform the required calculations automatically, thus providing the user with the benefits of automated computation without requiring knowledge of a scientific computing language. Data from a study of the pullout test method are used to illustrate the use of spreadsheet software to perform linear regression and determine the required correlation relationship. In addition, a simplified technique is proposed for using the results of in-place tests to make a reliable estimate of the characteristic strength of structural concrete. The in-place characteristic strength permits an evaluation of structural safety during construction.