Title:
Flexural Noncontact Lap Splices in Ultra-High- Performance Concrete
Author(s):
Jason Hock, Kevin R. Mackie, Georgios Apostolakis, and Tiancheng Wang
Publication:
Structural Journal
Volume:
121
Issue:
1
Appears on pages(s):
119-132
Keywords:
bond strength; cover; development length; noncontact lap splice; slip; ultra-high-performance concrete (UHPC)
DOI:
10.14359/51739189
Date:
1/1/2024
Abstract:
Ultra-high-performance concrete (UHPC) has the potential to
create more-durable structures that can be economized based
on performance criteria. An experimental program consisting of
47 small-scale, noncontact lap splice specimen tests under fourpoint
loading was conducted to investigate the bond strength and
slip mechanisms within UHPC. Parameters studied in the testing
matrix included aspect ratio, clear cover, lap length, and bar size.
An inverse analysis on a numerical model of the flexural tests was
employed to compute the bond stress-slip parameters representative
of each specimen group. Results showed an enhanced bond
stress-slip behavior inducing reinforcing bar yielding for clear
cover greater than 1.5db and lap splice lengths of 9db. The postpeak
response of all specimens exhibited ductile behavior, including
those that experienced slip. By controlling the lap parameters and
using this ductile mechanism, the maximum bar stress can be
limited to a target value in the design process.