Modified post-installed adhesive anchorage test: Investigation of in-place compressive strength of concrete and influential factors

Abstract

This paper presents the Modified Post-installed Adhesive Anchorage test (MPAA) as a method for evaluating the in-place compressive strength of concrete. It considers various influential factors, including test surface characteristics, concrete strength, anchorage depth, bolt diameter, and rebar location. Additionally, a formula for calculating concrete compressive strength, applicable to various influencing factors, was suggested. The findings demonstrate the effectiveness of MPAA in assessing in-place compressive strength of concrete with a high degree of precision. Following pull-out test, the prevalent failure modes observed were vertebral failure and vertebral-bond composite failure. Moreover, diverse concrete strengths, anchorage depths, and rebar locations demonstrated differing impacts on failure modes, while test surface characteristics and bolt diameter exerted less noticeable effects. The pull-out force-displacement curve during pull-out displayed three discernible phases: the elastic phase, crack propagation phase, and descent phase. When conducting on-site assessments, it is advisable to situate test points on the side surfaces of the members. Furthermore, factors like cover thickness and rebar location should be thoroughly evaluated when positioning test points. This encompasses the prudent choice of anchorage depth and bolt diameter to improve test precision. The suggested formula for calculating compressive strength exhibited minimal error and is applicable in determining concrete compressive strength for a wide range of practical engineering contexts. This study not only establishes a theoretical underpinning and offers support for standard revisions but also furnishes valuable guidance for conducting on-site testing procedures.