s

Control Tests for 

Code Concretegy and hnolo te Tec Concre
Objectives

 Purpose Frequency Planning Testing fresh concrete
Purpose of Contr

T i est

ing

 Provides assurance that 

specified properties are achieved

 Provides feedback for mix

adjustments
Frequency of Contro

Testing

 Random tests occur to acce

material or component

 Process control tests are 

nonrandom and occur often allow process adjustments

 Frequency depends on unifo

of l materials
Frequency of Contro

Testing

 Process control tests occur twice 

day at a batch plant

 Frequency reduces as material 

uniformity is established for a pr

 ASTM C1451, Standard Practice f

Determining Uniformity of Ingredof l Concrete From a Sing

le Source
Avoiding Problems

QA/QC Plan

 Communication & Plannin

Communication

& Plannin

 Pre-Construction Meeting

 Owner Architect/Engineer General Contractor Sub-Contractors Contractors

Ready-Mix Supplier Mix SupplierConcrete Contractor

 QA/QC Inspector
Qualification Qualification of Perso

Perso

 Knowledge and  Certification Re

 ASTM C94 ACI 318

 ACI Concrete F

Technician

 ACI Concrete S

Testing Techni

 ACI Concrete L

Testing Techni
Testing Fresh 

Concrete  Sampling

 Temperature Consistency Density and yield Air content Strength
Reference Document

 C31, Standard Practice for Making and Curing Conc

S i i h Fi ld

ASTM

Specimens in t

he Fi

eld

 C39, Standard Test Method for Compressive Streng

Concrete Specimens

 C138, Standard Test Method for Density (Unit Weig

Standard Test Method for Density (Unit Wei

Air Content (Gravimetric) of Concrete

 C143, Standard Test Method for Slump of Hydrauli

Concrete

 C172, Standard Practice for Sampling Freshly Mixe C173, Standard Test Method for Air Content of Fre

Concrete b

y the Volumetric Method

 C231, Standard Test Method for Air Content of Fre

Concrete by the Pressure Method

 C1064, Standard Test Method for Temperature of 

Portland Cement Concrete
Sampling and Testing 

Fresh ConcretFresh Concret

 Pur

pose: 

truly reprsample of mixed co

 ASTM C17 Required 

except te
ASTM C172 Procedure

 1 ft3 minimum All water added Middle 

portion of 

batch 

 Com

posite 

samples

 Re-mixed Time limits
Frequency of Samplin

Frequency of Samplin

 Once 

p y, p 

er day,

pe

but not less than

 Once for each 11

yd

3) of each class 

each day but noeach day, but no

than:

 Once for each 50

(5000 ft

2) of slab 

surface area placsurface area plac

day
Temperature

ASTM C1064 ASTM C1064

 Purpose of Test: To determine 

concrete temperature falls withispecification limits.
ASTM C1064 Procedure ASTM C1064 Procedure

 Pl d i i t ith 

Place 

device in concre

te with 

75 mm (3 in) clear cover in all 

directions

 Allow temperature to stabilize 

Allow temperature to stabilize 

at least 2 minutes

 Complete test within 5 minute

sampling
Typical Specification Lim

ASTM C94 ACI 306 ACI 306

-For Cold Weather Con

For Cold Weather Con

Section SizeMin. Temperature 

< 12 in. 55° F (13

° C)

12-36 in. 50° F (10° C36-72 in. 45° F ( 7° C

> 72 in. 40

° F ( 5

° C

Do Not Exceed 90°F (32°C) 

 ACI 305-For Hot Weather Con

Try Not to Exceed 90 Try Not to Exceed 90

°F (32

°C)
Controlling Temperatur

g p

ACI 305- Hot 

Weather Concreting 

ACI 30

Weather C
Slump

ASTM C143 ASTM C143

 Purpose of Test Purpose of Test: To determine To determine

consistency of fresh concrete ancheck uniformity from batch to b
Importance of Slump

 Slump is NOT a measure of Workabi Do NOT compare slumps from differ

concrete mix designs.

Should MixturePl 

aceme

Conditio

Slump.
ASTM C143 Procedure ASTM C143 Procedure

 Place concrete in 3 Place concrete in

3

equal layers within cone

 Vertically raise cone Vertically raise cone

steadily

 Measure height 

distance of original center
Typical Specification Lim

 ASTM C94:

Specified Slump Toler

< 2 in. ± 1⁄2 

2-4 in. ± 1 in.

> 4 in. ± 11⁄2 in.

If Specified “Not to Exceed”

Max.Slum

p Toler

< 3 in. - 11⁄2 

>3 in. - 21⁄2 in.
Controlling Slump

(Control Consistenc

 w/cm Wash Wat Agg Moist

Agg. Moist

 Temperatu Haul Time Haul Time Mixing Tim Admixture 

 Water R Air-Entra
How about water adde

site?

 ACI 301 ACI 302 ASTM C94 ACI 301, ACI 302, ASTM C94

all 

limited addition of water...

 If water addition is allowed, the 

ratio and the maximum water ratio and the maximum water

content may not be exceeded
Density and Density and Yield

ASTM C138

 Purpose o

find the we

foot of freswhich is usedeterminin

g 

cement fact
Importance of Yield

 Ready Mixed 

is sold on the the volume ounhardened (

3

d

3

m

)

3 or y

d

3

).

 Should receiv

ord d b

dere

d an b
ASTM C138 Procedure ASTM C138 Procedure Procedure

 Place concrete into container of kn

mass and volume

 Measure mass of concrete and cal

density

 Calculate yield using batch weight Calculate air content usin

g theoret

density
Typical Specification im

ypical Specification Lim

ASTM C94

Material Tolerance

%

ASTM C94

 Cement: ±1% SCM’s: ±1% Aggregate: ±2% Water: ±1% Admixtures: ±3%
Controlling Controlling Yield and Yield and 

Under Ordering Under Ordering

 Water co

Water co

 Air Conte Subgrade

 moistu levelne

(highs 

 overex

 Distortion  Waste (4 Waste (4-
Air Content

ASTM C231 ASTM C173 ASTM C231, ASTM C173

 P 

ASTM C231

Purpose 

determine content o

ASTM C231

concrete.

ASTM C173
Importance of Air

 Durability

 Freeze

-Thaw

 Scaling

Photos courtesy of M. Thomas
ASTM C231 Procedure ASTM C231 Procedure

 Place concrete Place concrete Apply pressure Release and read gauge Release and read gauge Make corrections for 

aggregates
ASTM C173 Procedure ASTM C173 Procedure

 Place concrete Add alcohol and water Add alcohol and water Seal container, shake 

and roll

 Release and read
Air Content Acceptance Air Content Acceptance



+ 1.5 of the Specified Percen

 Low – Additional Dosage of A High

 Additional Revolutions in 

Mixer/Agitator

 Air Detraining Admixtures Vibrator in Mixer/Agitator

 Not To Exceed total Mixing o

Time
Controlling Air Content

 Cement content;

 Transport Placemen

 fineness, alkali

 Aggregates; 

 fineness shape

 Placemen Consolida Finishing

 fineness, shape

 Admixtures w/c Slump;

 <3-in., >6-in.

 Temperature Altitude Mixing speed, time, 

capacity
Compressive Strengt

ASTM C31

 Purpose of 

check for ade

mix proportistrength. 
Importance of Streng

 To determin

of strength fremoval, anstructure. 

ASTM C3ASTM C3
ASTM C31 Procedure ASTM C31 Procedure

 Place concrete into molds on level 

Place concrete into molds on level 

 Move as little as possible leaving t

Move as little as possible, leaving t

specimens near the placement site

 Shelter the specimens from hot or 

weather
Strength Tests

 Test Methods

 ASTM C39 

–

C

ylind

 ASTM C78 – Simple  ASTM C496 – Tens

 Cores and In-Situ Te

Transporting Test Transporting Test Specim

Specim

 At least 8 hours a Packed in a sturd Surrounded with 

wet saw dust

 Protected against  Transport time le

hours
Test Cylinders at the La

y

 ASTM C39 ASTM C39

– Testing Cyli

Testing Cyli

 Capping

 ASTM C617 – Capping ASTM C1231 – Unb d

on

d

 Measurements Testing

 Maximum Load Strength, within 10 psi

 C i l F il Conical F

ailure
Controlling Cylinder Stren

 w/cm Water Ad Air Conten Aggregate  Handling Curing Tem Testing Er
Typical Specification Lim

ASTM C94 

( ) ACI 318

)

 The average of any three conse

stren

g q, th tests shall be e

qual to, 

greater than, the specified stren

 No individual strength test shal

No individual strength test shal

than 500 psi [3.5 MPa] below thspecified strength, 

f

‘c.
Low Strengths

T t I di id l St th Average Average 

1 3110 + 3080 = 6190 3095

- 

Average

of 3 

Tests

Average

of 2

Strengths

Indi

vidual Strength

s

f’

c = 3000

Tes

t

3 3120 + 3160 = 6280 3140 3092 2 3060 + 3020 = 6080 3040

- 

6 3040 3100 6140 3070 2965 5 2800 + 2860 = 5660 2830 2988 4 2980 + 3010 = 5990 2995 3058 7 2510 +2460 = 4970 2485 27956 3040 + 3100 = 6140 3070 2965
What to Do? What to Do?

 Increase Cementitious Materia Reduce W/CM Closer Control of Air Content Change Mixture Proportions Reduce Delivery Time Im

p yg rove Qualit

y of Testin

g
Apply Judgment Judgment

 1 in 100 Tests Fail Even Thou

Concrete Strength and UnifoMay Be Satisfactory May Be Satisfactory

 Allowance for Statistically Ex

Variations

 Investigation of Low Strengt

 Nondestructive Testing Compressive Strengths of Co
Apply Judgment Judgment
Summary

 Control testing provides 

assurance and feedback

 ASTM standards for test 

methods

 Apply judgment