advancements in cement concrete research and testing

Advancements in Cement Concrete

Research and Testing

John Grieco –Director of R&M

June 19,2019

A need arises to incorporate

Different types of methods and technologies

for the evaluation of quality characteristics and mix

properties of concrete used for MassDOT construction

projects

Summary

2

0 20 40 60 80 100

Surface Resistivity (kΩ-cm)

Cement Concrete Cylinder Set

45 psi

SAM

Number

Ring Shrinkage

Super Air Meter / Freeze and Thaw

Surface Resistivity test

Maturity Meter

2019 Innovation & Mobility Exchange

What has R&M been Focused on

2019 Innovation & Mobility Exchange 3

Freeze Thaw Damage


• Takes on average 100 days

• Cannot be reproduced in the field

Freeze Thaw Testing


Reference: FHWA

Super Air Meter

❑ Air Meter Type B

➢ Can only measure

total air content


❑ Super Air Meter

➢ Provides air content

➢ SAM number

Super Air Meter / Freeze Thaw

7

❑ Study by Dr. Tyler Ley, Oklahoma State University

Fre

eze

Th

aw

Dura

bili

ty F

acto

r


Continuing the Research


9

Description of the methodologies to determine the permeability of concrete

Surface Resistivity Test

AASHTO T 358

❖ Electrical Resistivity

❖ Created in the 2000s

❖ Non-destructive

❖ Concrete Age: 28 days

❖ Aprox. 2 minutes per set

❖ Low cost

Rapid Chloride Penetrability Test

AASHTO T 277

❖ Cumulative Current Passing

❖ Created in the 1970s

❖ Destructive

❖ Concrete Age: 90 days

❖ Aprox. 2 work days per set

❖ High cost



60

70

80

90

100

0 30 60 90 120 150 180 210 240 270 300 330 360

Cum

mula

tive C

urr

ent

Passin

g

Time (minutes)

Cummulative Current Passing

Charge (Trapezoidal Area) = 1870 Coulomb 28.9 28.3 26.4 30.829 28.3 26.4 30.8

0

10

20

30

40

50

0° 90° 180° 270°

Surf

ace R

esis

tivity (

kΩ

-cm

)

Angle (°)

Surface Resistivity Test Results

Average SR = 28.6 kΩ-cm

10

Description of the methodologies to determine the permeability of concrete


Chloride Permeability Surface Resistivity (kΩ-cm) Charge Passed (C)

100 by 200 mm (4 by 8 in.)

High < 12 > 4000

Moderate 12-21 2000-4000

Low 21-37 1000-2000

Very Low 37-254 100-1000

Negligible > 254 < 100


0 10 20 30 40 50 60 70 80 90

Surface Resistivity (kΩ-cm)

28-day Concrete Cylinder Sets Surface Resistivity ResultsSummer 2018

Cement Concrete Cylinder Set

High Moderate Low Very Low


11

Chloride Permeability Surface Resistivity Test

100 by 200 mm (4 by 8 in.)

High < 12

Moderate 12-21

Low 21-37

Very Low 37-254

Negligible > 254


4%

21%

51%

24%

Overall 28-day Concrete Cylinder Sets Surface Resistivity Results Summer 2018

High Moderate Low Very LowPermeability



While mixes are showing low permeability, some mixes have excess of paste content

36%

64%

SRT 28 Day Samples Concrete Mixes



7%

47%

46%

SRT Results for 28 Day HP Mixes

Moderate Low Very Low

Other Mixes

HP Mix

y = 8458.4x-0.752

R² = 0.9184

0

50

100

150

200

250

0 1000 2000 3000 4000 5000

SR

T (

kΩ

-cm

)

RCPT Charge (Coulomb)

Surface Resistivity Test compared to Rapid Chloride Permeability Test


14

Why is the Surface Resistivity Test an alternative to the Rapid

Chloride Penetrability Test?

Reliable

Fast Paced

Non-Destructive

Reference: Giatec Scientific Inc.

Cost Effective




y = 0.4105x + 5.1117R² = 0.3103

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

80.00

0 10 20 30 40 50 60

Surf

ace R

esis

tivity

(kΩ

-cm

)

Concrete Age (days)

“Conventional” MassDOT Construction Mixes SRT Evaluation for a Single Industry

y = 0.8273x + 7.8497R² = 0.8858

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

80.00

0 10 20 30 40 50 60

Surf

ace R

esis

tivity (

kΩ

-cm

)

Concrete Age (days)

“HP” MassDOT Construction Mixes SRT Evaluation for a Single Industry

How consistent are the SRT results when evaluating Concrete Mixes by Industry?

Hig

h

Mo

de

rate

Low

Ve

ry L

ow

Hig

h

Mo

de

rate

Lo

w

Ve

ry L

ow

How can we lower permeability (increase durability)?

Surface Resistivity Test (SRT)

16

❑ Lower water/cement ratio

❑ Use Supplementary Cementitious

Materials (SCMs)

❑ Control paste volume to minimize

cracking

❑ Optimize the gradation of the coarse

and fine aggregate (Tarantula Curve)

❑ Perform good curing practices Reference: FHWA

Reference: The Concrete Countertop Institute

Reference: The Portland Cement Association

Reference: The Constructor

Reference: Putzmeister – Best Support Underground

05

10152025

Perc

ent

Reta

ined

Sieve Size


Maturity Meters

17

❑ Time Temperature Factor (TTF)

❑ Mixture specific relationship

➢ Thermal history

➢ Strength

❑ ASTM C1074


Maturity Meters


Maturity Meters

19

Co

mp

ressiv

e S

tre

ng

th (

psi)


Maturity Meters


Questions?


The State’s Reptile Problem


SRT Compared to RCPT

23

y = 8458.4x-0.752

R² = 0.9184

0

50

100

150

200

250

0 500 1000 1500 2000 2500 3000 3500 4000 4500

SR

T (

kΩ

-cm

)

RCPT Charge (Coulomb)

56-day Surface Resistivity Test compared to Rapid Chloride Permeability TestNegligible

Very Low

Low

Moderate

High


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