Methods for 

Preventing ASR in 

New Construction

Results of Field Exposure Sites

December 2013

i 

Technical Report Documentation Page

1. Report No. 2. Government Accession No. 3. Recipient's Catalog No.

FHWA-HIF-14-004 

4. Title and Subtitle 5. Report Date

Methods for Preventing ASR in New Construction: Results of Field December 2013 

Exposure Sites 

6. Performing Organization Code

7. Author(s) 8. Performing Organization Report No.

Michael D.A. Thomas, Kevin J. Folliard, Benoit Fournier, Thano 

Drimalas, and Sabrina I. Garber 

9. Performing Organization Name and Address 10. Work Unit No. (TRAIS)

The Transtec Group

6111 Balcones Drive 11. Contract or Grant No.

Austin, TX 78731 DTFH61-06-D-00035 

12. Sponsoring Agency Name and Address 13. Type of Report and Period Covered

FHWA Office of Pavement Technology

1200 New Jersey Ave. SE 

Washington, DC 20590 

14. Sponsoring Agency Code

15. Supplementary Notes

Contracting Officer’s Representative (COR): Gina Ahlstrom, HIAP-10 

16. Abstract

As part of the FHWA ASR Development and Deployment Program, two sites were built to study ASR in new 

concrete construction. Concrete blocks were produced with a range of aggregates and cementitious materials and 

placed on outdoor exposure sites at the University of Hawaii in Manoa on the island of Oahu and at a DOT 

storage facility in Lawrence, Massachusetts. The main purpose of these studies was to (i) provide information on 

the reactivity of local aggregates which could be used as a benchmark to calibrate standard laboratory tests, (ii) 

determine the efficacy of various preventive measures for controlling ASR expansion, and (iii) provide data to 

validate guidelines such as AASHTO PP65-11. 

This document presents the preliminary findings from the Oahu and Lawrence exposure sites. 

 

17. Key Word 18. Distribution Statement

Alkali-silica reaction, concrete durability, prevention, No restrictions. This document is available to the 

construction, exposure, aggregate. public through the Federal Highway Administration 

(FHWA)

19. Security Classif. (of this report) 20. Security Classif. (of this page) 21. No. of Pages 22. Price

Unclassified Unclassified 31 N/A

Form DOT F 1700.7 (8-72) Reproduction of completed page authorized
ii
iii

SI* (MODERN METRIC) CONVERSION FACTORS 

APPROXIMATE CONVERSIONS TO SI UNITS

Symbol When You Know Multiply By To Find Symbol 

LENGTH 

in inches 25.4 millimeters mm 

ft feet 0.305 meters m 

yd yards 0.914 meters m 

mi miles 1.61 kilometers km 

AREA 

in2 square inches 645.2 square millimeters mm2

ft2 square feet 0.093 square meters m2

yd2 square yard 0.836 square meters m2

ac acres 0.405 hectares ha 

mi2 square miles 2.59 square kilometers km2

VOLUME 

fl oz fluid ounces 29.57 milliliters mL 

gal gallons 3.785 liters L 

ft3 cubic feet 0.028 cubic meters m3 

yd3 cubic yards 0.765 cubic meters m3 

NOTE: volumes greater than 1000 L shall be shown in m3

MASS oz ounces 28.35 grams g

lb pounds 0.454 kilograms kg

T short tons (2000 lb) 0.907 megagrams (or "metric ton") Mg (or "t") 

TEMPERATURE (exact degrees) o

F Fahrenheit 5 (F-32)/9 Celsius o

C 

or (F-32)/1.8 

ILLUMINATION 

fc foot-candles 10.76 lux lx 

fl foot-Lamberts 3.426 candela/m2 cd/m2

FORCE and PRESSURE or STRESS 

lbf poundforce 4.45 newtons N 

lbf/in2 poundforce per square inch 6.89 kilopascals kPa 

APPROXIMATE CONVERSIONS FROM SI UNITS 

Symbol When You Know Multiply By To Find Symbol 

LENGTH mm millimeters 0.039 inches in 

m meters 3.28 feet ft 

m meters 1.09 yards yd 

km kilometers 0.621 miles mi 

AREA mm2 square millimeters 0.0016 square inches in2 

m2 square meters 10.764 square feet ft2 

m2 square meters 1.195 square yards yd2 

ha hectares 2.47 acres ac 

km2 square kilometers 0.386 square miles mi2 

VOLUME 

mL milliliters 0.034 fluid ounces fl oz 

L liters 0.264 gallons gal 

m3 cubic meters 35.314 cubic feet ft3 

m3 cubic meters 1.307 cubic yards yd3 

MASS 

g grams 0.035 ounces oz

kg kilograms 2.202 pounds lb

Mg (or "t") megagrams (or "metric ton") 1.103 short tons (2000 lb) T 

TEMPERATURE (exact degrees) o

C Celsius 1.8C+32 Fahrenheit oF 

ILLUMINATION 

lx lux 0.0929 foot-candles fc 

cd/m2 candela/m2 0.2919 foot-Lamberts fl

FORCE and PRESSURE or STRESS 

N newtons 0.225 poundforce lbf 

kPa kilopascals 0.145 poundforce per square inch lbf/in2

*SI is the symbol for the International System of Units. Appropriate rounding should be made to comply with Section 4 of ASTM E380. 

(Revised March 2003)
iv
v 

TABLE OF CONTENTS

1. Introduction ............................................................................................................................................... 1

2. Exposure Site in Oahu, Hawaii ................................................................................................................. 1

2.1 Experimental Details ........................................................................................................................... 2

2.1.1 Materials ...................................................................................................................................... 2

2.1.2 Standard Aggregate Expansion Tests........................................................................................... 5

2.1.3 Concrete Blocks ........................................................................................................................... 5

2.2 Results ............................................................................................................................................... 10

2.3 Discussion ......................................................................................................................................... 11

2.4 Conclusions ....................................................................................................................................... 13

3. Exposure Site in Lawrence, Massachusetts ............................................................................................ 13

3.1 Experimental Details ......................................................................................................................... 14

3.1.1 Materials .................................................................................................................................... 14

3.1.2 Standard Aggregate Expansion Tests......................................................................................... 17

3.1.3 Concrete Blocks ......................................................................................................................... 17

3.2 Results ............................................................................................................................................... 20

3.3 Discussion ......................................................................................................................................... 23

3.4 Conclusions ....................................................................................................................................... 24

References ................................................................................................................................................... 25
vi

List of Figures

Figure 1. Completed Exposure Site at the University of Hawaii at Manoa, Hawaii .................................... 2

Figure 2. Length-Change Measurements Using a Demec-Type Gauge........................................................ 8

Figure 3. Map of Exposure Site .................................................................................................................... 9

Figure 4. Photograph of Block 4 at 805 days .............................................................................................. 10

Figure 5. Expansion of Blocks with Imported Known Reactive Aggregates ............................................. 11

Figure 6. Photographs of Cracked Blocks with Placitas Aggregate Cast in 2011 (top) and 2013 (middle) 

and Jobe Sand Cast in 2013 (bottom) ........................................................................................... 12

Figure 7. Completed Exposure Site in Lawrence, Massachusetts............................................................... 14

Figure 8. Length-Change Measurements Using a Demec-Type Gauge...................................................... 20

Figure 9. Expansion of Local Aggregates Tested in Concrete Prism Test (ASTM C 1293) ...................... 21

Figure 10. Expansion of Blocks on Exposure Site in Lawrence, Massachusetts ........................................ 22

Figure 11. Cracking in Blocks on Exposure Site after One Year ............................................................... 23

List of Tables

Table 1. “Local” Aggregates (including Orca sand from British Columbia) ................................................ 3

Table 2. Imported (Known) Reactive Aggregates from the Mainland ......................................................... 4

Table 3. Details of Cementitious Materials .................................................................................................. 4

Table 4. Details of Concrete Mixtures .......................................................................................................... 6

Table 5. “Local” Aggregates ....................................................................................................................... 15

Table 6. Standard Reactive Aggregates ...................................................................................................... 16

Table 7. Details of Cementitious Materials ................................................................................................ 16

Table 8. Details of Concrete Mixtures ........................................................................................................ 18
1 

1.INTRODUCTION

Alkali-silica reaction (ASR) is one of the principal forms of concrete deterioration in North 

America that can lead to the premature failure of concrete structures including highways, 

bridges, tunnels, barrier walls, and other components of transportation infrastructure. Although 

many details of the reaction are understood, there exists a need for further research to ensure the 

prevention of damaging ASR in new concrete structures and to help mitigate the effects of the 

reaction in existing ASR-affected structures. In 2006, FHWA initiated the FHWA ASR 

Development and Deployment Program to assist State transportation agencies in dealing with 

ASR by providing tools which included: guidelines for surveying and recognizing ASR in the 

field, protocols for the prevention, diagnosis, and repair of ASR, and educational materials 

(including a one-day workshop, webinar, and a Facts Book) for training State employees. The 

protocol for preventing ASR was used as the basis for developing a national specification 

(AASHTO PP65-11). 

The program also included a number of field application and demonstration projects; these 

included nine sites (in eight different states) where existing ASR-affected structures were 

subjected to a range of treatments and subsequently monitored to evaluate the efficacy of the 

treatments, and two sites (one in Hawaii and the other in Massachusetts) to study ASR in new 

concrete construction. The findings from the nine studies on treating ASR-affected structures 

have been reported elsewhere (Thomas et al. 2013a; 2013b). 

To study ASR in new construction, concrete blocks have been produced with a range of 

aggregates and cementitious materials and placed on outdoor exposure sites at the University of 

Hawaii in Manoa on the island of Oahu in Hawaii and at a Department of Transportation (DOT) 

storage facility in Lawrence, Massachusetts. The main purpose of these studies is to (i) provide 

information on the reactivity of local aggregates which can be used as a benchmark to calibrate 

standard laboratory tests (the results of which are often equivocal), (ii) determine the efficacy of 

various preventive measures for controlling ASR expansion, and (iii) provide data to validate 

guidelines such as AASHTO PP65-11. 

The following chapter presents the preliminary findings from the exposure site in Oahu, Hawaii, 

and chapter 3 presents the same information for the site in Lawrence, Massachusetts. 

2. EXPOSURE SITE IN OAHU, HAWAII

The exposure site in Hawaii was constructed in June 2011 and is situated at the Magoon 

Research and Instruction Facilities, which is part of the College of Tropical Agricultural and 

Human Resources at the University of Hawaii at Manoa (see Figure 1). A total of 40 concrete 

mixtures were produced (30 in 2011 and an additional 10 mixes in January 2013), and blocks 

(0.38 x 0.38 x 0.71 m, 15 x 15 x 28 in.) from these mixtures were placed on the exposure site. A 

number of local aggregates (coarse and fine) from various quarries on the islands and an 

imported sand from British Columbia, that is used by some Hawaiian concrete producers, were 

used together with cements of varying alkali, fly ash, and a lithium-nitrate admixture. Known
2 

reactive aggregates from three different sources were also used. These aggregates have been used 

to produce blocks on other exposure sites including the site in Lawrence, Massachusetts that was 

constructed under this program and other sites in Texas, Ontario, and New Brunswick. Having 

the same-size blocks with nominally identical composition on different sites will allow the effect 

of environmental exposure to be assessed. These blocks will be monitored periodically to 

determine the onset of cracking (by visual inspection) and length change. Laboratory tests have

been conducted on these aggregates and the outcome of the tests will be compared when longterm test data (≥ 10 years) from the exposure site become available. At the time of writing, only 

two-year data are available from the exposure site. Continued monitoring of the blocks (beyond 

two years) will be performed by representatives of the University of Hawaii, Department of Civil 

Engineering. 

Figure 1. Completed Exposure Site at the University of Hawaii at Manoa, Hawaii 

(January 2013) 

2.1 Experimental Details

2.1.1 Materials

2.1.1.1 Aggregates 

“Local” basaltic aggregates from six different quarries located on the Hawaiian Islands were 

included in the study; coarse aggregate and manufactured sand were available from each source. 

Note that two sources of coarse aggregate from the Halawa quarry were used; one of these, 

Halawa – Grade B, is not an approved DOT source. An imported siliceous sand (Orca) from 

British Columbia in Canada was also used as this sand has been used by some Hawaiian concrete 
3 

producers. Details of these aggregates are given in Table 1 together with expansion data from the 

accelerated mortar-bar test (AMBT), ASTM C1260/AASHTO T303, and concrete prism test 

(CPT), ASTM C1293, conducted at the University of Texas. Note that coarse and fine aggregates 

from Waikoloa on the “Big Island” of Hawaii were used to cast one block in 2011 and further 

samples were collected to cast additional blocks in 2013. 

Table 1. “Local” Aggregates (including Orca sand from British Columbia) 

Agg. 

ID Source

1

AMBT at 

14 days (%) 

2

CPT

1 year at 

38°C (%)

60 days at 

60°C (%)

Coarse Aggregates

1 Halfway Bridge, Kauai - - - 

2 Ameron, Oahu 0.084 -0.003 -0.013 

3 Hilo 0.633 

4 Halawa, Oahu 0.627 0.003 0.007 

5 Halawa – Grade B 0.221 0.016 - 

6 Waimea 0.015 - - 

7 Waikoloa (2011) - - 

8 Waikoloa (2013) - - - 

Fine Aggregates

9 Halfway Bridge, Kauai - 0.018 

10 Ameron, Oahu 0.076 0.004 -0.001 

11 Hilo 0.718 0.029 

12 Halawa, Oahu 0.526 0.019 0.230*

13 Waimea 0.007 

14 Waikoloa (2011) 0.522 0.287 

15 Orca (British Columbia) 0.222 0.003 0.001 

16 Maui Dune Sand 0.015 0.011 0.014 

1

AMBT = Accelerated Mortar-Bar Test, ASTM C1260 or AASHTO T303

2

CPT = Concrete Prism Test, ASTM C1293

*

Expansion value at 6 months 

In addition to the local aggregates, three known reactive aggregates were also used, and these are 

detailed in Table 2. Typical expansion data from tests conducted at the University of Texas at 

Austin are also shown for these aggregates. 
4 

Table 2. Imported (Known) Reactive Aggregates from the Mainland

Agg. 

ID Source Description

Typical expansion (%) 

1

AMBT at 14 

days

2

CPT at 1 

year

Coarse Aggregates

UT1 Placitas, NM Rhyolitic volcanic rocks 

and granite 

with quartz 0.820 0.159 

Fine Aggregates

UT2 Jobe, TX Mixed quartz/chert/feldspar sand 0.640 0.582

UT3 Wright, TX Mixed quartz/chert sand 0.290 0.270 

1

AMBT = Accelerated Mortar-Bar Test, ASTM C1260 or AASHTO T303

2

CPT = Concrete Prism Test, ASTM C1293

2.1.1.2 Cementitious Materials

Two portland cements were used to produce the concrete mixtures; these are designated HAC

(high-alkali cement) and LAC (low-alkali cement) with alkali contents of 1.20% and 0.55% 

Na2Oe, respectively. For some concrete mixtures both cements were used and blended to 

produce intermediate alkali levels. Local fly ash from Hawaii (HFA) and an imported fly ash 

from China (CFA) were used in some of the concrete mixtures. Chemical analyses of the 

cementitious materials are given in Table 3.

Table 3. Details of Cementitious Materials

ID Oxides (% mass)

SiO2 Al2O3 Fe2O3 CaO MgO SO3 Na2Oe

High-alkali cement (HAC) 20.2 4.3 3.0 61.3 3.4 3.7 1.20 

Low-alkali cement (LAC) - - - - 2.93 2.59 0.55 

Local fly ash (HFA) - - - 25.99 - 9.85 1.26 

Chinese fly ash (CFA) 49.54 35.71 4.85 4.41 1.06 0.53 1.07 

2.1.1.3 Chemical Admixtures 

A polycarboxylate high-range, water-reducing admixture (HRWA) meeting the requirements of 

ASTM C494 was used. Some concrete mixtures also contained a lithium-based ASR-suppressing 

admixture composed of a 30% solution of lithium nitrate (LiNO3). 
5 

2.1.2 Standard Aggregate Expansion Tests 

All of the local aggregates were tested in accordance with the standard accelerated mortar bar 

test (ASTM C1260/AASHTO T303), AMBT, and most were also tested in the concrete prism 

test (ASTM C1293), CPT; the CPT was conducted at the standard temperature of 38°C (100°F) 

and at 60°C (140°F). The expansion data from these tests are given in Table 1. 

2.1.3 Concrete Blocks 

Table 4 provides information on the type of aggregate, cement, fly ash, and presence of lithium 

for the 40 concrete mixtures produced during this study. With the exception of mix numbers 20, 

23, and 30, the total cementitious materials content of the concrete mixtures was 420 kg/m3

 (708 

lb/yd3), the water-to-cementitious-materials ratio was w/cm = 0.42, and the coarse-to-fineaggregate ratio was C/F = 60/40. The dosage of HRWA was adjusted for each batch to provide 

suitable workability for compaction (slump range 125 to 175 mm, 5 to 7 in.). Where lithium 

nitrate was used the dose was adjusted to provide a lithium-to-alkali-molar ratio of [Li]/[Na+K] 

= 0.74 based on the alkali available from the portland-cement component of the mixture only. 

This yields a dose of 4.6 liters of 30% lithium nitrate solution per kilogram of equivalent alkali, 

4.6 L/kg Na2Oe (0.55 gal/lb Na2Oe). This is often referred to as the “standard” lithium dose 

required to control ASR for many reactive aggregate types. 
6 

Table 4. Details of Concrete Mixtures

Mix 

# 

1

Posn

Aggregate Cement 

alkali 

(% Na2Oe)

Fly Ash2 or 

3 Lithium

Expansion of Blocks (%)

Coarse Fine 109/234 

4 days

265 

days

571 

days

805 

days

1 29 Halfway Bridge Halfway Bridge 1.20 0.003 0.005 -0.009 0.020

2 30 Ameron Ameron 1.20 -0.034 0.000 -0.010 0.011

3 28 Hilo Hilo 1.20 0.006 -0.008 0.003 0.006

4 14 Placitas Halawa 1.20 0.146 0.224 0.375 0.438

5 24 Halawa Jobe 1.20 0.021 0.024 0.035 0.049

6 27 Halawa Wright 1.20 0.015 0.006 0.018 0.020

7 20 Halawa Halawa 1.20 0.005 -0.005 0.002 0.012

8 19 Halawa Orca 1.20 0.006 -0.003 0.005 0.010

9 22 Halawa 65/35 Halawa/Orca 1.20 0.016 -0.003 0.015 0.013

10 12 Halawa Halawa 1.20 100 LiNx 0.011 0.001 0.014 0.014

11 7 Halawa Halawa 1.20 125 LiNx 0.010 0.009 0.012 0.026

12 21 Halawa Halawa 0.55 -0.007 -0.021 -0.002 0.000

13 13 Halawa Halawa 0.75 0.000 -0.006 0.007 0.010

14 4 Halawa Halawa 0.95 -0.015 -0.009 -0.015 0.013

15 6 Halawa Halawa 1.20 20 CFA -0.008 0.004 -0.028 0.013

16 15 Halawa Halawa 1.20 30 CFA -0.006 -0.002 -0.005 -0.013

17 11 Halawa Halawa 1.20 20 HFA 0.007 -0.005 0.003 0.002

18 16 Halawa Halawa 1.20 30 HFA 0.007 -0.005 -0.005 -0.003

19 18 Halawa Orca 0.95 0.002 -0.007 0.003 0.007

20 9 Halawa Plant 3000-psi Mix -0.012 -0.007 -0.001 0.004

21 17 Halawa Jobe 1.20 30 HFA 0.006 0.001 0.003 0.008

22 3 Halawa Wright 1.20 30 HFA -0.008 0.003 0.015 0.026

23 8 Halawa Plant 7000-psi Mix -0.007 -0.007 -0.006 -0.001

24 10 Halawa Grade B Halawa 1.20 -0.014 -0.002 0.020 0.009

25 5 Halawa Grade B Halawa 0.55 -0.003 -0.011 0.002 0.003

26 2 Halawa Grade B Halawa 1.20 30 HFA 0.010 0.006 0.002 0.016

27 1 Waimea Waimea 1.20 0.008 -0.001 0.014 0.016
7 

28 23 Waikoloa Waikoloa 0.004 -0.022 0.014 0.018

29 25 Maui Maui -0.022 -0.039 -0.029 -0.024

30 26 Halawa Plant Marine Mix -0.024 -0.025 -0.029 -0.013

31 34 Waikoloa Waikoloa 0.55 0.009

32 33 Waikoloa Waikoloa 0.80 -0.032

33 32 Waikoloa Waikoloa 1.20 0.013

34 31 Waikoloa Waikoloa 0.80 20 CFA 0.003

35 39 Waikoloa Waikoloa 0.80 20 FA + 50 

LiNx 0.005

36 36 Waikoloa Waikoloa 1.20 20 CFA 0.007

37 35 Waikoloa Waikoloa 1.20 30 CFA 0.011

38 38 Waikoloa Jobe 1.20 0.278

39 37 Placitas Waikoloa 1.20 0.224

40 40 Waikoloa Waikoloa 1.20 100 LiNx 0.014

1

Position on exposure site (see Figure 3) 

2

Fly ash levels expressed as percentage by mass of total cementitious material

3

Lithium contents expressed as percentage of standard dose – e.g. 100 LiNx: [Li]/[Na+K] = 0.74; 50 LiNx: [Li]/[Na+K] = 0.37 

4

First measurement at 109 days for blocks 1 to 30 (cast in June 2011) and at 234 days for blocks 31 to 40 (cast in January 2013) 
8 

Concrete for 27 of the first 30 mixtures was batched, mixed, and cast at Hawaiian Cement’s 

Halawa Plant in June 2011. For each mixture 0.14 m3 (5 ft3) of concrete was mixed in a drum 

mixer, placed into the forms for the concrete blocks, and consolidated in two layers using an 

immersion vibrator. Stainless steel pins were cast into the blocks to permit measurements of 

length change to be made using a Demec-type strain gauge (see Figure 2). The blocks were cured 

under wet burlap and plastic for one day before the forms were stripped. The blocks were then 

moist-cured for a further (approximately) six days under wet burlap before being transported 

approximately 16 km (10 mi) to the Magoon Research Facilities in Manoa where they were 

placed on a layer of granular fill and exposed to the elements (see Figure 1), at which time the 

“zero-day” reference length-change measurement was carried out. 

Three of the first 30 blocks (mix numbers 20, 23, and 30) were produced using commercial mix 

designs and materials from the Halawa ready-mix concrete plant. These mixtures were batched 

in the plant and truck-mixed but otherwise the manufacture and subsequent treatment of the 

blocks was the same as the other 27 blocks. 

Figure 2. Length-Change Measurements Using a Demec-Type Gauge 
9 

Length-change measurements of these 30 blocks were conducted again at 109, 265, 571, and 805 

days. At 805 days (August 2013) representatives of the University of Hawaii (UH) Department 

of Civil Engineering also made length-change measurements using different Demec gauges. All 

future measurements will be performed by UH.

Concrete for the second series of 10 mixtures was batched, mixed, and cast at the University of 

Hawaii in January 2013. Similar procedures were used and the blocks were shipped to the 

exposure site at an age of 2 to 3 days when the zero-day measurement was made. These blocks 

were also measured in August 2013 by both the FHWA team and UH, at which time the blocks 

were 234 days old. 

Figure 3 shows the location of the forty different mixtures on the exposure site. 

Figure 3. Map of Exposure Site 
10 

2.2 Results

The results of the laboratory expansion tests performed on the local aggregates collected for this 

study are presented in Table 1. All of the basaltic aggregates (coarse and fine) produced 

expansion in excess of 0.10% at 14 days in the accelerated mortar bar test (AMBT). However, 

with one exception these same aggregates did not produce deleterious expansion in the concrete 

prism tests (CPT) at 38°C (100°F). The fine aggregate from Waikoloa did produce damaging 

expansion in the CPT at this temperature although the coarse aggregate from the same source did 

not. As a result of this behavior, additional blocks were cast with the Waikoloa aggregate in 

January 2013 to confirm whether this source truly is reactive and to evaluate the efficacy of 

preventive measures (fly ash and lithium). 

None of the blocks containing the local Hawaiian (basaltic) aggregates have shown deleterious 

expansion to date. Only one block, Mix 28 with Waikoloa aggregate, exhibited cracking at 805 

days (see Figure 4) but this is not thought to be a result of ASR as the expansion is still less than 

0.020% at this age. Consideration will be given to sampling the block at a later age and 

conducting a petrographic evaluation to determine whether there is any evidence of ASR. 

Figure 4. Photograph of Block 4 at 805 days (August 2013) 

(Photo on right is an enlargement of area in blue box on left)

Figure 5 shows the expansion of blocks containing the “imported” known reactive aggregates 

from Texas (Jobe and Wright) and New Mexico (Placitas). Of the blocks manufactured in 2011 

only the block with Placitas (Mix 4) showed rapid expansion and cracking, and this is consistent 

with behavior observed for this aggregate on other exposure sites. The block containing Wright 

sand has not yet expanded, and this is not unexpected as this sand is more slowly reactive than 

the Jobe and Placitas. The behavior of the block with Jobe is surprising as this sand has produced 

very rapid expansion when combined with high-alkali cement in blocks on other exposure sites. 

To further investigate this apparent anomaly additional blocks were cast with Jobe and Placitas 

in January 2013. The data in Figure 5 show both blocks to expand rapidly this time, and the 

magnitude and rate of expansion of the 2013 Placitas block is very similar to the 2011 Placitas 

block. A corner of 2011 Jobe block was removed using a concrete saw and examined in the 
11 

laboratory; this confirmed that the sand was indeed Jobe. It is suspected that an error occurred 

during the batching of the 2011 Jobe block and that low-alkali cement was inadvertently used 

instead of high-alkali cement. If this is indeed the case the block is expected to start expanding at 

some point in the future and, at that time, consideration will be given to removal of another small 

sample from this block for the purpose of determining the alkali content of the concrete. 

-0.05

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0 200 400 600 800

Expansion (%)

Age (days)

Placitas 2011

Jobe 2011

Wright 2011

Placitas 2013

Jobe 2013

Figure 5. Expansion of Blocks with Imported Known Reactive Aggregates 

Figure 6 shows the condition of some of the blocks with known reactive aggregates. The 

photographs were taken in August 2013 when the 2011 blocks were at an age of 805 days and 

the 2013 blocks were just 234 days old. The cracking exhibited in the blocks constructed with 

Placitas (2011 and 2013) and Jobe (2013) is symptomatic of ASR. 

2.3 Discussion

Continued and regular monitoring of the blocks on the exposure site is required to produce a 

meaningful database that can be used to: (i) calibrate laboratory tests (both existing tests and new 

tests), (ii) evaluate the efficacy of preventive measures under field conditions, and (iii) test the 

current guidelines such as AASHTO PP65-11. The current plan is that ongoing monitoring will 

be conducted by representatives of the University of Hawaii Department of Civil Engineering. 
12 

Figure 6. Photographs of Cracked Blocks with Placitas Aggregate Cast in 2011 (top) and 

2013 (middle) and Jobe Sand Cast in 2013 (bottom) 

(Photos on right are enlargements of areas in blue box on left)
13 

2.4 Conclusions

1. An exposure site was developed on Oahu, Hawaii in June 2011. 

2. Concrete blocks from 30 different mixtures produced with a number of local (basaltic) 

aggregates and 3 known highly-reactive aggregates, and with various preventive measures, 

are exposed on the site. An additional 10 blocks were added to the site in January 2013 to 

further investigate the behavior of aggregate from the Waikoloa Quarry on the island of 

Hawaii (“Big Island”). 

3. At the time of writing the blocks are 805 or 234 days old and none of those produced with 

Hawaiian aggregates have shown expansion in excess of 0.040%. 

The monitoring needs to be continued for at least 10 years to make best use of the data. 

3. EXPOSURE SITE IN LAWRENCE, MASSACHUSETTS

The Lawrence exposure site was constructed in June 2012 at a Massachusetts Department of 

Transportation (MassDOT) storage facility in Lawrence, Massachusetts (see Figure 7). A total of 

73 concrete mixtures were produced, and blocks (0.38 x 0.38 x 0.71 m, 15 x 15 x 28 in.) from 

these mixtures were placed behind the storage building. Eleven local aggregates (coarse and fine) 

were used together with cements of varying alkali, supplementary cementing materials (SCM), 

and a lithium-nitrate admixture. Known reactive aggregates from three different sources were 

also used. These aggregates have been used to produce blocks on other exposure sites including 

the site in Hawaii that was constructed under this program and other sites in Texas, Ontario, and 

New Brunswick. Having the same-size blocks with nominally identical composition on different 

sites will allow the effect of environmental exposure to be assessed. These blocks will be 

monitored periodically to determine the onset of cracking (by visual inspection) and length 

change. Laboratory tests are being conducted on similar mixtures, and the outcome of the tests 

will be compared when long-term test data (≥ 10 years) from the exposure site become available. 

At the time of writing, only one-year data are available from the exposure site. Continued 

monitoring of the blocks (beyond one year) will be performed by MassDOT. 
14 

Figure 7. Completed Exposure Site in Lawrence, Massachusetts (June 2012) 

3.1 Experimental Details

3.1.1 Materials

3.1.1.1 Aggregates 

Eleven sources of “local” aggregate were included in the study. The majority of the sources are 

located within the state of Massachusetts. Details of these aggregates are given in Table 5 

together with historical expansion data from the accelerated mortar-bar test (AMBT), ASTM 

C1260/AASHTO T303, conducted by, or on behalf of, MassDOT. The last two columns in Table 

5 present the results for testing conducted under this study, and these are discussed later in 

section 3.3. 
15 

Table 5. “Local” Aggregates

Agg. 

ID

Description 1MassDOT: 

AMBT 14 

days (%) 

2

Univ. Texas 

3

AMBT 

14 days 

(%)

4

CPT 180 

days (%) 

Coarse Aggregates

1 

Diorite (mainly); granitic & 

volcanic (traces) 0.05 - 0.09 0.095 0.014 

2 

Mixed Diorite/gneiss/granite/

schist 0.04 - 0.09 0.066 0.035 

3 Pinkish meta-granite 0.20 - 0.32 0.072 0.032 

4 Mixed gneiss/granitic > 0.1 0.324 0.113 

5 Mixed gneiss/schist/quartzite 0.50 - 0.54 0.063 0.041 

6 Greywacke/sandstone 0.58 - 0.62 0.573 0.127 

Fine Aggregates

7 Mixed gneiss/quartzite/quartz/ 

feldspar sand 0.09 - 0.10 0.066 0.018 

8 Mixed quartzite/gneiss/quartz/ 

feldspar sand 0.20 - 0.21 0.147 0.053 

9 Mixed gneiss/quartzite/quartz/ 

feldspar sand 0.20 - 0.26 0.239 0.016 

10 Mixed gneiss/schist/quartzite/

quartz/feldspar sand 0.38 - 0.40 0.327 0.027 

11 Mixed 

sand

granitic/quartz/feldspar 0.037 0.023 

1

Range of results from tests conducted by, or on behalf of, MassDOT prior to the exposuresite study

2

Results from tests conducted by the University of Texas on the aggregate samples used in 

the exposure-site study

3

AMBT = Accelerated Mortar-Bar Test, ASTM C1260 or AASHTO T303

4

CPT = Concrete Prism Test, ASTM C1293

In addition to the local aggregates three known reactive aggregates were also used, and these are 

detailed in Table 6. Typical expansion data from tests conducted at the University of Texas at 

Austin are also shown for these aggregates.
16 

Table 6. Standard Reactive Aggregates

Agg. 

ID Source

Description Typical Expansion (%) 

1

AMBT at 14 

days 

2

CPT at 1 

year 

Coarse Aggregates

UT1 Placitas, NM Rhyolitic volcanic rocks 

and granite 

with quartz 0.820 0.159 

Fine Aggregates

UT2 Jobe, TX Mixed quartz/chert/feldspar sand 0.640 0.582 

UT3 Wright, TX Mixed quartz/chert sand 0.290 0.270 

1

AMBT = Accelerated Mortar-Bar Test, ASTM C1260 or AASHTO T303

2

CPT = Concrete Prism Test, ASTM C1293

3.1.1.2 Cementitious Materials 

Two portland cements were used to produce the concrete mixtures; these are designated HAC 

(high-alkali cement) and LAC (low-alkali cement) with alkali contents of 1.10% and 0.66% 

Na2Oe, respectively. For some concrete mixtures both cements were used (50/50 blend) to 

produce a moderate-alkali cement (MAC) with an equivalent alkali content of 0.88% Na2Oe. The 

following supplementary cementing materials (SCM) were used in some of the concrete 

mixtures: Class F fly ash (FA), slag (SG), and silica fume (SF). Chemical analyses of the 

cementitious materials are given in Table 7. 

Table 7. Details of Cementitious Materials

ID Oxides (% mass)

SiO2 Al2O3 Fe2O3 CaO MgO SO3 Na2Oe

High-alkali cement (HAC) 20.31 5.02 2.61 62.01 2.01 4.31 1.10 

Low-alkali cement (LAC) 20.21 4.95 2.41 62.42 2.14 2.54 0.66 

Fly ash (FA) 55.78 25.90 7.41 3.44 1.04 0.34 1.03 

Slag (SG) 35.81 10.79 0.77 39.20 11.50 2.66 0.70 

Silica fume (SF) 93.30 0.03 1.28 0.65 0.49 0.26 0.74 
17 

3.1.1.3 Chemical Admixtures 

A polycarboxylate high-range, water-reducing admixture (HRWA) meeting the requirements of 

ASTM C494 and a synthetic air-entraining admixture (AEA) meeting the requirements of ASTM 

C260 were used. Some concrete mixtures also contained a lithium-based ASR-suppressing 

admixture composed of a 30% solution of lithium nitrate (LiNO3). 

3.1.2 Standard Aggregate Expansion Tests 

All eleven of the local aggregates were tested in accordance with the standard accelerated mortar 

bar test (ASTM C1260/AASHTO T303), AMBT, and concrete prism test (ASTM C1293), CPT. 

The 14-day expansion data for the AMBT are given in Table 5. The latest expansion data for the 

CPT are also reported in Table 5; note that this is a one-year test and thus the data are incomplete 

at this time. 

3.1.3 Concrete Blocks 

Table 8 provides information on the type of aggregate, cement, SCM, and presence of lithium for 

the 73 concrete mixtures produced during this study. In all cases the total cementitious materials 

content of the concrete mixture was 420 kg/m3

 (708 lb/yd3), the water-to-cementitious-materials 

ratio was w/cm = 0.42, and the coarse-to-fine-aggregate ratio was C/F = 60/40. The dosage of 

admixtures (HRWA and AEA) were adjusted for each batch to provide suitable workability for 

compaction (slump range 125 to 175 mm, 5 to 7 in.) and an air content in the range of 5 to 8%. 

Where lithium nitrate was used the dose was adjusted to provide a lithium-to-alkali-molar ratio 

of [Li]/[Na+K] = 0.74 based on the alkali available from the portland-cement component of the 

mixture only. This yields a dose of 4.6 liters of 30% lithium nitrate solution per kilogram of 

equivalent alkali, 4.6 L/kg Na2Oe (0.55 gal/lb Na2Oe). This is often referred to as the “standard” 

lithium dose required to control ASR for many reactive aggregate types.

The mixture proportions, particularly the level of SCM, were selected to bracket the 

recommended replacement levels in AASHTO PP65-11. Also each of the local aggregates was 

used in control mixes without prevention with three different cement alkali levels to determine 

the threshold alkali required to produce damaging ASR. 
18 

Table 8. Details of Concrete Mixtures

Mix 

#

Aggregate Portland Cement SCM/Lithium Expansion of Blocks (%)

Type % Na2Oe 91 days 371 days

1 3 LAC 0.66 Control -0.021 0.008

2 MAC 0.88 Control -0.014 0.022

3 HAC 1.10 Control -0.010 0.016

4 20% FA -0.016 0.011

5 30% FA -0.018 0.013

6 35% SG -0.018 0.014

7 50% SG -0.008 0.017

8 15% FA + 4% SF -0.013 0.010

9 20% SG + 4% SF -0.019 0.016

10 Lithium -0.012 0.016

11 9 LAC 0.66 Control 0.004 0.009

12 MAC 0.88 Control -0.004 0.007

13 HAC 1.10 Control -0.004 0.011

14 HAC 1.10 Control 0.007 0.020

15 UT1 - Placitas HAC 1.10 Control 0.024 0.107

16 5 LAC 0.66 Control -0.002 0.010

17 MAC 0.88 Control -0.004 0.008

18 HAC 1.10 Control -0.004 0.012

19 20% FA -0.015 0.009

20 30% FA -0.013 0.004

21 35% SG 0.003 0.025

22 50% SG -0.016 0.012

23 15% FA + 4% SF 0.000 0.018

24 20% SG + 4% SF 0.003 0.025

25 Lithium 0.000 0.013

26 2 LAC 0.66 Control 0.002 0.004

27 MAC 0.88 Control 0.004 0.017

28 HAC 1.10 Control -0.002 0.017

29 10 LAC 0.66 Control 0.005 0.018

30 MAC 0.88 Control 0.001 0.017

31 HAC 1.10 Control 0.006 0.021

32 50% Slag -0.008 0.004

33 20% FA -0.017 0.004

34 30% FA -0.029 -0.008

35 35% SG -0.017 0.002

36 15% FA + 4% SF 0.000 0.011

37 20% SG + 4% SF -0.006 0.035

38 Lithium 0.010 0.027

39 7 LAC 0.66 Control 0.002 0.015

40 MAC 0.88 Control 0.004 0.013

41 HAC 1.10 Control -0.001 0.016
19 

42 8 LAC 0.66 Control -0.001 0.016

43 MAC 0.88 Control 0.012 0.018

44 HAC 1.10 Control 0.005 0.011

45 4 LAC 0.66 Control 0.018 0.018

46 MAC 0.88 Control 0.010 0.023

47 HAC 1.10 Control 0.009 0.026

48 UT2 - Jobe HAC 1.10 Control 0.137 0.370

49 UT3 - Wright HAC 1.10 Control 0.003 0.028

50 1 LAC 0.66 Control 0.006 0.018

51 MAC 0.88 Control 0.020 0.019

52 6 LAC 0.66 Control 0.017 0.007

53 MAC 0.88 Control 0.007 0.018

54 HAC 1.10 Control 0.007 0.038

55 20% FA -0.013 0.001

56 30% FA 0.005 0.004

57 35% SG 0.001 0.009

58 50% SG -0.019

59 15% FA + 4% SF 0.008 0.015

60 20% SG + 4% SF 0.003 0.006

61 Lithium 0.001 0.004

62 MAC 0.88 20% FA 0.004 0.009

63 30% FA -0.004 0.007

64 35% SG -0.005 0.012

65 50% SG -0.009 0.005

66 5 MAC 0.88 20% FA -0.004 0.001

67 30% FA 0.000 0.000

68 35% SG 0.004 0.016

69 50% SG -0.019 -0.001

70 3 MAC 0.88 20% FA 0.005 0.014

71 30% FA 0.003 0.012

72 35% SG 0.000 0.012

73 50% SG -0.003 0.009

Concrete was batched, mixed, and cast on the exposure site. For each mixture 0.14 m3 (5 ft3) of 

concrete was mixed in a drum mixer, placed into the forms for the concrete blocks, and 

consolidated in two layers using an immersion vibrator. Stainless steel pins were cast into the 

blocks to permit measurements of length change to be made using a Demec-type strain gauge 

(see Figure 8). The blocks were cured under wet burlap and plastic for one day before the forms 

were stripped. The blocks were then moist-cured for a further (approximately) six days under 

wet burlap before being placed on a layer of granular fill and exposed to the elements (see Figure 

7) at which time the “zero-day” reference length-change measurement was carried out. 
20 

Length-change measurements were conducted again at 91 and 371 days. At 371 days 

representatives of MassDOT also made length-change measurements using different Demec 

gauges. All future measurements will be performed by MassDOT.

Figure 8. Length-Change Measurements Using a Demec-Type Gauge 

3.2 Results

The results of the laboratory expansion tests performed on the eleven local aggregates collected 

for this study are presented in Table 5. The results from the AMBT conducted at the University 

of Texas (UT) are in broad agreement with the range of data provided by MassDOT for tests 

conducted on samples from the same source at various times prior to this study. The exceptions 

are the results for the sands from samples 3 and 5. The test data for these two aggregates tested at 

UT indicate the aggregates to be innocuous (14-day expansion below 0.10%) whereas data 

supplied by MassDOT indicated both aggregates to be potentially deleteriously reactive. The 

discrepancy is largest for aggregate 5. 
21 

At the time of writing, the CPT was not complete; this is a 1-year test and only 180-day 

expansion data are available. However, the data available do confirm that aggregates 4, 5, 6, and 

8 are deleteriously reactive as the 180-day expansion value already exceeds the 1-year expansion 

limit of 0.040%. Both aggregates 2 and 3 show expansion values in excess of 0.030% at 180 

days and, based on experience, it is highly likely that these aggregates will exceed the 0.040% 

limit at 1 year. One or more of the other local aggregates will probably exceed the limit at one 

year also. 

The relationship between expansion and time for the 11 aggregates tested in the CPT are 

presented in Figure 9. Although the tests are not sufficiently advanced for definitive statements 

to be made regarding the reactivity of the aggregates, the spread of data do confirm that the 11 

aggregate samples selected represent a wide range in terms of alkali-silica reactivity (as 

intended). 

Figure 9. Expansion of Local Aggregates Tested in Concrete Prism Test (ASTM C 1293) – 

Data to 180 days only (Note: specified test duration is 1 year) 

The results of the laboratory expansion tests performed on the three known reactive aggregates 

collected for this study are presented in Table 6. The results of the AMBT and CPT confirm that 

these aggregates are reactive, the reactivity ranging from highly-reactive to very-highly-reactive 

based on the criteria in AASHTO PP65-11. 
22 

The expansion values for the concrete blocks after three months and one year on the exposure 

site are presented in Table 8. Figure 10 shows the expansion versus age for the three known 

reactive aggregates together with aggregate 6. Aggregate 6 was selected because it shows the 

highest expansion among the 11 local aggregates and has been implicated as a contributor to 

ASR in a number of structures in New England. The Jobe aggregate, which is considered to be 

one of the most, if not the most, reactive aggregates in North America, produces expansion in 

excess of 0.040% after just 91 days on the exposure site. After 1 year, the Placitas aggregate has 

also produced expansion in excess of 0.040%, but none of the other blocks have reached this 

level of expansion at this age. However, the block with aggregate 6 and high-alkali cement has 

expanded by 0.038% at 1 year. Significant expansion of the blocks produced with local 

aggregates is not expected after one year. Damaging expansion and cracking due to ASR often 

takes 5 to 10 years, and sometimes even longer, to occur under field conditions. Indeed in many 

cases the blocks exhibit shrinkage (negative values in Table 8) during the first year, and this is 

expected behavior. 

Figure 10. Expansion of Blocks on Exposure Site in Lawrence, Massachusetts

Visual inspection of the blocks at one year revealed significant cracking in four blocks (Figure 

11); these were: Block 15 with Placitas, Block 48 with Jobe, Block 49 with Wright, and Block 54 

with aggregate 6. Note that at 91 days only Block 48 with Jobe showed any signs of cracking. 

All of these blocks were produced with the high-alkali cement (HAC) without either SCM or 

lithium. 
23 

Figure 11. Cracking in Blocks on Exposure Site after One Year

3.3 Discussion

As the concrete prism tests are only six months old and the concrete blocks are just one year old, 

it is too soon to draw many inferences from the data at this time. However, the six-month prism 

expansion data has confirmed that four of the local aggregates are certainly deleteriously alkalisilica reactive, having already exceeded the one-year expansion limit. The indications are that at 

least two or more of the remaining aggregates are likely to fail the limit at one year. The concrete 

prism test data also reveal that the different aggregates exhibit a significant range of reactivity. 

The aggregates were selected on the basis of existing mortar-bar test results and petrographic 

data to provide a suite of aggregates of varying composition and reactivity; this selection appears 

to have been successful.

There is some discrepancy between the accelerated mortar-bar test (AMBT) data collected by 

MassDOT at various periods before the commencement of the study and the data from the 

testing performed at the University of Texas (UT) on the aggregates collected for the study. 

Furthermore, there is some disagreement between the AMBT and concrete prism test (CPT) data 

for the same aggregates tested at UT, as some of the aggregates that do not produce deleterious 
expansion in the AMBT (expansion < 0.10% at 14 days) have already exceeded the limit 

(0.040%) for the CPT at 6 months or look likely to do so before 1 year. It may be necessary to 

repeat the AMBT for some of these cases to check the incongruity.

Two of the highly reactive “standard” aggregates (Placitas and Jobe) have already produced 

excessive expansion in blocks on the exposure site which confirms that the exposure conditions 

are conducive to ASR. The greywacke aggregate (number 6) produces an expansion of 0.038% 

in the control block with high-alkali cement, and some slight cracking is already in evidence. 

Continued and regular monitoring of the blocks on the exposure site is required to produce a 

meaningful data base that can be used to: (i) to calibrate laboratory tests (both existing tests and 

new tests), (ii) evaluate the efficacy of preventive measures under field conditions, and (iii) test

the current guidelines such as AASHTO PP65-11. The current plan is that ongoing monitoring 

will be conducted by representatives of MassDOT. 

It is expected that MassDOT will conduct further AMBT and CPT tests using the same 

aggregate-SCM/lithium combinations used in the blocks for the purpose of evaluating these tests 

as methods for determining the efficiency of preventive measures (i.e., by comparing the 

laboratory data with the long-term performance of blocks). It is also recommended that the same 

combinations be tested in other promising laboratory performance tests such as the miniconcrete-prism test currently being developed at Clemson University under a FHWA-funded 

research program. 

3.4 Conclusions

1. An exposure site was developed in Lawrence, Massachusetts in June 2012. 

2. Concrete blocks from 73 different mixtures produced with 11 local aggregates and 3 known 

highly-reactive aggregates, and with various preventive measures, are exposed on the site. 

3. After 1 year 2 of the blocks have shown expansion in excess of 0.040%. 

4. The monitoring needs to be continued for at least 10 years to make best use of the data. 

24 
25 

REFERENCES

AASHTO. 2008. “Standard Method of Test for Accelerated Detection of Potentially 

Deleterious Expansion of Mortar Bars Due to Alkali-Silica Reaction.” AASHTO T303,

American Association of State and Highway Transportation Officials, Washington, DC, 6 p. 

AASHTO. 2011. “Standard Practice for Determining the Reactivity of Concrete Aggregates and 

Selecting Appropriate Measures for Preventing Deleterious Expansion in New Concrete 

Construction.” PP65-11, American Association of State and Highway Transportation Officials,

Washington, DC, 24 p. 

ASTM. 2013. “Standard Specification for Chemical Admixtures for Concrete.” ASTM C494, 

ASTM International, West Conshohocken, PA, 10 p. 

ASTM. 2007. “Standard Test Method for Potential Alkali Reactivity of Aggregates (Mortar-Bar

Method).” ASTM C1260, ASTM International, West Conshohocken, PA, 5 p. 

ASTM. 2008. “Standard Test Method for Determination of Length Change of Concrete Due to

Alkali-Silica Reaction.” ASTM C1293, ASTM International, West Conshohocken, PA, 7 p. 

Michael D.A. Thomas, Kevin J. Folliard, Benoit Fournier and Thano Drimalas. 2013a. “Methods 

for Evaluating and Treating ASR-Affected Structures: Results of Field Application and 

Demonstration Projects -Volume I: Summary of Findings and Recommendations.” FHWA 

Report FHWA-HIF-14-0002. 

Michael D.A. Thomas, Kevin J. Folliard, Benoit Fournier, Thano Drimalas and Sabrina I. 

Garber. 2013b. “Methods for Evaluating and Treating ASR-Affected Structures: Results of Field 

Application and Demonstration Projects -Volume II: Details of Field Applications and 

Analysis.” FHWA Report FHWA-HIF-14-0003. 


FHWA-HIF-14-004