chapter 3 rigid pavement - DOT On-Line Publications - Department ...

TIEBAR PULL-OUT TESTS
Proper consolidation of the concrete around the tiebars is essential to the
performance of longitudinal construction joints. Adjacent lanes should not be
constructed until the project engineer has had.opportunity to test the pull-
out resistance of the tiebars. Acceptance of the tiebats should be based on
the results of the tests for resistance to pull-out. The project engineer
will select 15 tiebars from the first day's placement, after the concrete has
attained a flexural strength of 550 psi. The tiebars will be tested to 12,000
lbs. or to a slippage of l/32-inch, whichever occurs first. The average of the
results of these pull-out tests, divided by the spacing of the tiebars, will
be used to determine the pull-out resistance in lbs. per linear foot.
If the test results on the first day's placement are well within the test
requirements shown below, additional testing will be at the discretion of the
project engineer and will be based on comparison of the installation methods
and spacings of the first day's placement with subsequent placements.
If the results of the pull-out tests are less than the minimum requirements
specified for the width of concrete being tied, the contractor shall instalk
additional tiebars to provide the minimum average pull-out resistance
required, as directed by the project engineer. Testing of the supplemental
tiebars will be at the discretion of the Engineer.
Tiebars shall be installed by methods and procedures such that the tiebars
will develop the minimum average pull-out resistance specified without any
slippage exceeding l/32-inch in accordance with the following table:
Tied Width of Pavement
(Distance from Joint
Being Constructed to
Nearest Free Edge).
12 feet or less 2200
Over 12 feet to 17 feet 3200
Over 17 feet to 24 feet 4500
Over 24 feet to 20 feet 5200
Over 28 feet to 36 feet 6800
Over 36 feet 9000
3.1.16
Average Pull-out
Resistance of
Tiebars, lbs./L.F. .
of joint, minimum.