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June 2013 © CRMCA.com1
Hidden Landmines in Concrete Specifications
Eric T. Misenheimer, PEChair, CRMCA Technical
Committee
June 22, 2013
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What is a Specification?
A specification (often abbreviated as spec) is an explicit set of requirements to be satisfied by a material, design, product, or service. – ASTM
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Why should we be concerned?
Specification Requirements:– Aggregates
Alkali Silica Reactivity – ASR
– Concrete Properties Shrinkage Permeability Air Void Analysis Freeze-Thaw Durability Scaling Resistance
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Why should we be concerned?
Time– From 16 days to 68 weeks
– Most tests around 30 days, but some take SIGNIFICANTLY longer
– Communicate the time frame(s) to potential bidders so that they are aware of schedule impacts.
– Avoid last minute job award/submittal requests
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Why should we be concerned?
Cost– From $400 per test to $2500 per test
– Make sure that ALL anticipated testing costs are captured and expensed
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C 1260/C 1567 Example – Standard**Note age of data allowed**
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C 1260/C 1567 Example – 30 days
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Why should we be concerned?
Variance from ASTM Standard– Communicate with lab performing test to make
sure variance is noted and incorporated and test is run to completion
– Check on additional cost of variance
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C 157 - Example
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C 457 Example
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C 457/C 666 Example
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Why should we be concerned?
Design vs. Construction Testing
– Construction stage testing can be very difficult
Most tests are intended for lab conditions
– Many construction stage tests are affected by conditions beyond our control
Placement, consolidation, finishing and curing
– Make sure design and construction testing responsibilities/liabilities are covered in your contractual/PO agreements
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C 1202 Example
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Test – Standard – Time – Cost
Test Purpose ASTM Time Cost CommentsStandard Required
Petrographic Exam - Aggregates
C 295 ** $2000 to $2500 ** No specific time for test, but highly specialized and very few labs perform this test. Can take 30 days to get results.
Alkali Reactivity - Aggregates
C 1260 16 to 30 days
$1000 to $1600 Standard calls for 16 days but some specs extend to 30 days
Alkali Reactivity – w/ Cementitious
C 1567 16 to 30 days
$1000 to $1600 Standard calls for 16 days but some specs extend to 30 days
Shrinkage C 157 ** $500 to $1200 ** Standard calls for 28 days initial curing followed by up to 64 weeks. Typically modified to 7 days initial curing followed by 28 days.
Microscopic Air Void Analysis
C 457 ** $400 to $600 ** No specific time for test, but highly specialized and very few labs perform this test. Can take 30 days to get results.
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Test – Standard – Time – Cost
Test Purpose ASTM Time Cost CommentsStandard Required
Freeze-Thaw Resistance C 666 40 to 60 days**
$1200 to $1500 **Procedure after 14 days(typical) curing
Permeability (?) C 1202 ** $500 to $700 **Curing method controls length. Typically 28 days.
Scaling Resistance C 672 50 days** $800 to $1000 **Procedure after 28 days(typical) curing
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Why should we be concerned?
Time
– Time noted in tables is for the test only Does noted include gathering/delivering materials to the
lab or mix/sample preparation
Costs– Costs noted in table are for standard test
procedures and any variance from the standard can have SIGNIFICANT effect on test costs.
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QUESTIONS ??
Thank you on behalf of the CRMCA Technical Committee
