Title: Behavior of ductile short-grouted seismic reinforcing bar–to–foundation connections under adverse construction conditions
Date Published: July - August 2020
Volume: 65
Issue: 4
Page Numbers: 33 - 50
Authors: Theresa C. Aragon, Yahya C. Kurama, and Donald F. Meinheit
https://doi.org/10.15554/pcij65.4-01

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Abstract

This paper describes an experimental investigation of the cyclic uniaxial behavior of a grouted reinforcing bar–to–foundation connection that can develop ductility under seismic loading even when constructed with adverse conditions. The connector comprises a cylindrical thin metal sleeve, with or without a taper, embedded inside the foundation and filled with flowable cementitious grout to anchor an ASTM A706 Grade 60 (414 MPa) steel reinforcing bar over a short embedment (bond) length. The paper extends previous published experiments involving 12 specimens on the performance of this connection under ideal laboratory conditions to eight additional tests conducted under simulated adverse effects from off-center placement of the reinforcing bar inside the connection sleeve and reduced grout strength by using excess water in the grout mixture. The specimens were tested with the objective of reaching close to the full ultimate strength of each reinforcing bar under a rigorous cyclic axial strain loading history. The test parameters included the grout product, bar embedment length, bar diameter, connector sleeve taper angle, and connector sleeve surface corrugations. The results showed that reinforcing bars anchored over a short embedment length of 12 times the bar diameter for no. 7 and 9 bars (22M and 29M) or 15 times the bar diameter for no. 11 bars (36M) can achieve ductile cyclic behavior even under the adverse conditions that were considered.