GA ACI Skipper SeminarJune 3, 2009

What do ACI 318 and 214 say about acceptance testing?- James M. Shilstone, Jr.

www.shilstone.com 1

What do ACI 318 and 214 say What do ACI 318 and 214 say

about acceptance testing?about acceptance testing?

-- James M. Shilstone, Jr.James M. Shilstone, Jr.

2009 Virgil Skipper Memorial Seminar

Georgia Chapter of ACI

What constitutes a What constitutes a failedfailed test?test?

Pass/Fail/?Pass/Fail/?

�� ff’’cc = 4000 psi= 4000 psi

�� 39003900

�� 39003900

38003800

�� 39003900

38003800

37003700

�� ??

�� ??

�� FailFail

(probably)(probably)

ACI 318ACI 318--05 says05 saysWhat constitutes a What constitutes a failedfailed test?test?

Pass/Fail/?Pass/Fail/?

�� ff’’cc = 4000 psi= 4000 psi

�� 39003900

�� 39003900

38003800

�� 39003900

38003800

37003700

�� ??

�� ??

�� FailFail

(probably)(probably)

But I want But I want allall my tests to my tests to

exceed exceed ff’’cc!!

It probably It probably ainain’’tt gonnagonna happen.happen.

(If it does you are paying extra(If it does you are paying extrafor your concrete.)for your concrete.)

ACI 318ACI 318

CommentaryCommentary

�� Field experienceField experience

�� Laboratory Laboratory w/cw/c

curvecurve

�� Other experience Other experience

or informationor information

GA ACI Skipper SeminarJune 3, 2009

What do ACI 318 and 214 say about acceptance testing?- James M. Shilstone, Jr.

www.shilstone.com 2

Field experience overdesignField experience overdesignACI 214 ACI 214

Evaluation of Strength Test ResultsEvaluation of Strength Test Results

What is What is ““standard deviationstandard deviation””?? FD for fun and profitFD for fun and profit

Field experience overdesignField experience overdesign Where does Where does ““2.332.33”” come from?come from?

GA ACI Skipper SeminarJune 3, 2009

What do ACI 318 and 214 say about acceptance testing?- James M. Shilstone, Jr.

www.shilstone.com 3

ACI 318 Overdesign AnalysisACI 318 Overdesign Analysis

ACI 214 Standards of ControlACI 214 Standards of Control Why Why ““probablyprobably”” fail?fail?

�� ff’’cc = 4000 psi= 4000 psi

�� 39003900

�� 39003900

38003800

�� 39003900

38003800

37003700

�� ??

�� ??

�� FailFail

(probably)(probably)

Does the test reflect the concrete?Does the test reflect the concrete?

Why do tests fail?Why do tests fail?

�� Concrete producerConcrete producer

•• Materials, mix, production, deliveryMaterials, mix, production, delivery

�� ContractorContractor

•• Add water, mishandle cylindersAdd water, mishandle cylinders

�� Testing labTesting lab

•• Improper curing, handling, testingImproper curing, handling, testing

Samples must be tested properlySamples must be tested properly

-- ACI 318ACI 318

GA ACI Skipper SeminarJune 3, 2009

What do ACI 318 and 214 say about acceptance testing?- James M. Shilstone, Jr.

www.shilstone.com 4

ASTM C31ASTM C31-- Making & CuringMaking & Curing

Assign responsibility in the Assign responsibility in the

preconstruction meeting (or the specs)preconstruction meeting (or the specs)

Other factorsOther factors

Aggregate pullout

ASTM C94ASTM C94

Ready Mixed ConcreteReady Mixed ConcreteWhat happens next?What happens next?

The Swiss Hammer (rebound hammer) is no longer The Swiss Hammer (rebound hammer) is no longer

acceptable for determining inacceptable for determining in--place strength.place strength.

Cores are different than cylindersCores are different than cylinders

Remember: A low test Remember: A low test

isnisn’’t necessarilyt necessarily

a failing testa failing test

GA ACI Skipper SeminarJune 3, 2009

What do ACI 318 and 214 say about acceptance testing?- James M. Shilstone, Jr.

www.shilstone.com 5

Questions?Questions?

www.shilstone.comwww.shilstone.com/library/library