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Next Generation Self-Healing Concrete:
Infusing Bacteria into Engineered Cementitious Composite
Presented by Benjamin G. Kaplan
Mentor: Paramita Mondal, PhD
(Mondal, 2012)
♜Holes in bridge deck(Rice, 2013)
♜D+ by ASCE(ASCE, 2013)
♜ $2.2 trillion to repair(Li, 2012)
(Wikipedia Commons)
America’s Crumbling Concrete
In t roductory
In format ion
Se l f -Hea l ing
Bacter ia l Concrete ECC Object ives Hypothes is
The Problem with Concrete
In t roductory
In format ion
Se l f -Hea l ing
Bacter ia l Concrete ECC Object ives Hypothes is
(Texturel ib .com)
♜Most used construction material on planet(The Concrete Conundrum, 2008)
♜Vulnerable to degradation
♜Diffi cult to repair
♜ 7% of carbon footprint( James, 2013)
♜ Calcium carbonate crystalizes in the matrix
♜ Water dissolves calcium hydroxide
♜ Healing agents consumed
♜ Can’t heal cracks larger than 100-200 µm ( Jonkers & Schlangen, 2008)
What is Self-Healing
In t roductory
In format ion
Se l f -Hea l ing
Bacter ia l Concrete ECC Object ives Hypothes is
(Breugel, 2007)
Concrete Cover
Steel
♜ Microbial Induced Calcium Carbonate Precipitation (MICCP)
♜ Urease: (CO(NH2)2) NH4+ + CO3
2–
♜ Ca+ + cell cell-Ca+
♜ cell-Ca+ + CO32– cell-CaCO
Bacterial Concrete: A Novel Approach to Self-Healing
In t roductory
In format ion
Se l f -Hea l ing
Bacter ia l Concrete ECC Object ives Hypothes is
(DeMuynck, 2007)
♜ Micromechanically-designed material “Tailored” to limit crack growth
♜ Tensile strain Strain hardening
♜ Limits crack size (up to 150 µm) natural self-healing occurs (Li, 2012)
♜ 500 times more ductile(Şahmaran, 2012)
♜ Double initial cost greatly lower end cost(L i , 2012)
Engineered Cementitious Composite
In t roductory
In format ion
Se l f -Hea l ing
Bacter ia l Concrete ECC Object ives Hypothes is
♜ 40% less concrete used(Li, 2012)
♜ 90% recovery of Resonant Frequency(Li, 2011)
♜ Cracks < 20 µm healed (Li, 2011)
(Panoramio.com)
ECC Self-Healing in the Field
In t roductory
In format ion
Se l f -Hea l ing
Bacter ia l Concrete ECC Object ives Hypothes is
Objectives
In t roductory
In format ion
Se l f -Hea l ing
Bacter ia l Concrete ECC Object ives Hypothes is
♜ Investigate infusion of bacteria into ECC
1. Hybrid’s healing capabilities
2. Healing in fi eld environments vs. laboratory
3. Compressive strength and amount of water absorbed (sorptivity) testing
Hypotheses
In t roductory
In format ion
Se l f -Hea l ing
Bacter ia l Concrete ECC Object ives Hypothes is
H01 Bacterial-ECC won’t show additional healing
H1 Bacterial-ECC will show greatest healing
H02 Lab healing = fi eld healing
H2 Lab healing > underground healing > exposed healing
H03 Compressive strength & sorptivity are equal for all groups
H3 Bacterial-ECC has greatest compressive strength &
lowest sorptivity
My Role in the Study
♜ Read 25 articles + 100 primer pages
♜ Independently conceived
♜ Determined parameters Environments Duration Test types
♜ Mixed, molded, and de-molded
♜ Tested specimens
♜ Analyzed all stats and wrote report(Kaplan, 2013)
M y R o le M a t e r i a l s S p e c im e n P r e p a r a t i o n
E n v i r o n m e nt s
R e so n a n t Fr e q u e n cy
Te s t i n g
C o m p / S o r p Te s t i n g &
S t a t s
Materials
♜Derived from ECC R0(L i , 2004)
♜ Changes to Formula: Less superplasticizer W/C = 0.395
♜Amounts Cement: 446.39g F110 si l ica
sand:446.05g Polyvinyl alcohol
(PVA) fi bers: 11.90g Water/medium:
178.90g (with 1.6g of super plasticizer for ECC)
Mix
♜ Solid media Yeast: 2.00g Ammonium sulfate
(NH4) 2 SO 4 : 1.00g Tris (HOCH 2) 3(CNH 2):
1.57g Agar: 2.00g
♜ Liquid media Yeast: 20.00 g in
400mL Ammonium sulfate:
10.00 g in 300mL 5.73 g of tris in
300mL
Nutrient Mediums
♜Sporosarcina pasteurii
♜Cultivation30°C Shaking
table24h petri dish
♜Repeated in vat
Bacteria Culturing
(Kaplan, 2013)
M y R o le M a t e r i a l s S p e c im e n P r e p a r a t i o n
E n v i r o n m e nt s
R e so n a n t Fr e q u e n cy
Te s t i n g
C o m p / S o r p Te s t i n g &
S t a t s
Specimen Preparation
(Kaplan, 2013)(Kaplan, 2013)
Cubes5.08 x 5.08 x 5.08
cm
Beams30.48 x 2.54 x
2.54 cm
Bisection12.7x2.54x2.54 cm
M y R o le M a t e r i a l s S p e c im e n P r e p a r a t i o n
E n v i r o n m e nt s
R e so n a n t Fr e q u e n cy
Te s t i n g
C o m p / S o r p Te s t i n g &
S t a t s
Environments
(Kaplan, 2013)
♜Laboratory Control Lime water 30°C Re-saturated
♜ Underground
Buried 21.6 cm
♜Exposed Dry, l itt le
rainfal l(Angel, 2013)
M y R o le M a t e r i a l s S p e c im e n P r e p a r a t i o n
E n v i r o n m e nt s
R e so n a n t Fr e q u e n cy
Te s t i n g
C o m p / S o r p Te s t i n g &
S t a t s
1.
2.
3.
Resonant Frequency Testing
♜ Wave propagation “stiff ness” measurement ASTM C215
♜ 7 days curing RF tests
♜ 3 point 1st crack
♜ RF re-measured
♜ 28 days healing
♜ RF re-measured
(Kaplan, 2013)
M y R o le M a t e r i a l s S p e c im e n P r e p a r a t i o n
E n v i r o n m e nt s
R e so n a n t Fr e q u e n cy
Te s t i n g
C o m p / S o r p Te s t i n g &
S t a t s
Compressive/Sorptivity Testing & Stats
♜ Sorptivity ASTM C642 standard 48 h oven drying Weighed, immersed, surface-dried, re- immersed, repeatedly 0, 0.25, 0.5, 1, 1.5, 2, 3, 6, 24, 48, 52.5 h
♜ Compressive Strength 48 h re-drying Forney QC-0410-D3 point load frame
♜ Stats T-test
✜ Independent✜ Paired✜ 1-tai led
Pearson’s R
α = 0.05
M y R o le M a t e r i a l s S p e c im e n P r e p a r a t i o n
E n v i r o n m e nt s
R e so n a n t Fr e q u e n cy
Te s t i n g
C o m p / S o r p Te s t i n g &
S t a t s
Self-Healing Beams
Genera l Trends
Hea l ing by Type
Hea l ing by Env i ro nme
nt
Sorp t i v i ty Resu l t s
Compress i ve S t rength
Resu l t s
Conc lus ions
♜RF increases as samples cure (age) Healing gains may be exaggerated
(absolutely)
Control: ECC Control: ECC + Medium
Control: ECC + Bacteria
Exposed: ECC Exposed: ECC + Medium
Exposed: ECC + Bacteria
Undergound: ECC Undergound: ECC + Medium
Undergound: ECC + Bacteria
0%
2%
4%
6%
8%
10%
12%
14%
Enviormental Group: Type
R.F.
% In
crea
se
Damage-Healing Correlation
Genera l Trends
Hea l ing by Type
Hea l ing by Env i ro nme
nt
Sorp t i v i ty Resu l t s
Compress i ve S t rength
Resu l t s
Conc lus ions
0.00% 5.00% 10.00% 15.00% 20.00% 25.00%
-5.00%
0.00%
5.00%
10.00%
15.00%
20.00%
Laboratory Environment
Linear (Laboratory Environment)
Underground Environment
Linear (Underground Environment)
Exposed Environment
Linear (Exposed Environment)Percent reduction in R.F. from damage
Perc
ent i
ncre
ase
in R
.F. a
fter r
ecov
ery
♜ Damage and RF regains: signifi cantly positive for all Lab: r = 0.90 & p = 0.000036 Exposed: r = 0.55 & p = 0.033 Underground: r = 0.86 & p = 0.00014
Differences amongst ECC types
Genera l Trends
Hea l ing by Type
Hea l ing by Env i ro nme
nt
Sorp t i v i ty Resu l t s
Compress i ve S t rength
Resu l t s
Conc lus ions
♜Healing for ECCbacteria significantly > ECCregular (p = 0.042) > ECCmedium (p = 0.007)
ECC ECC+ Medium ECC + Bacteria0%
2%
4%
6%
8%
10%
12%
Type
R.F.
% In
crea
se
Environmental Testing
Genera l Trends
Hea l ing by Type
Hea l ing by Env i ro nme
nt
Sorp t i v i ty Resu l t s
Compress i ve S t rength
Resu l t s
Conc lus ions
♜No sig. diff erence between lab and underground healing (p = 0.44)
Control Exposed Underground0%
2%
4%
6%
8%
10%
12%
14%
Environment
R.F
% In
crea
se
Sorptivity Testing
Genera l Trends
Hea l ing by Type
Hea l ing by Env i ro nme
nt
Sorp t i v i ty Resu l t s
Compress i ve S t rength
Resu l t s
Conc lus ions
♜ Not in line with expectations
♜ Micro-cracking?
0 10 20 30 40 50 600.00%
2.00%
4.00%
6.00%
8.00%
10.00%
12.00%
OPC-R-AOPC-R-BOPC-R-COPC-M-AOPC-M-BOPC-M-COPC-B-AOPC-B-BOPC-B-C
Time [hrs]
% W
ater
Upt
ake
OPC-R
OPC-MOPC-B
ECC-R
ECC-M
ECC-B
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80 Absorption Rate
Compressive Strength Testing
Genera l Trends
Hea l ing by Type
Hea l ing by Env i ro nme
nt
Sorp t i v i ty Resu l t s
Compress i ve S t rength
Resu l t s
Conc lus ions
♜ Microcracking OPC cube results inconclusive
♜ Dead bacteria weaker comp. strength(Ramachandran, 2001)
ECC-R-A ECC-R-B ECC-R-C ECC-M-A ECC-M-B ECC-M-C ECC-B-A ECC-B-B ECC-B-C ECC-R ECC-M ECC-B0
10000
20000
30000
40000
50000
60000
70000
Individual ECC Specimen ECC Type Average
Pasc
als R
equi
red
for F
ailu
re
Conclusions
♜ H1 confi rmed
♜ H02 serendipitously confi rmed in part
♜ Proof of concept for bacterial-ECC Future inquiries: more sophisticated methods
♜ Additional fi eld studies E.g. Underwater Diff erent seasons Diff erent climates
♜ Alternative measuring
♜ Infrastructure for the 21st century
Genera l Trends
Hea l ing by Type
Hea l ing by Env i ro nme
nt
Sorp t i v i ty Resu l t s
Compress i ve S t rength
Resu l t s
Conc lus ions
AcknowledgmentsI would like to thank my mentor, Dr. Paramita Mondal, her doctoral candidates, Pete Stynoski and Bin Zhang along with graduate student Jeevaka Somaratna, my science research advisors: Mr. David Keith, Mr. Ken Kaplan, and Ms. Stephanie Greenwald, and lastly my parents: Dr. Howard Kaplan and Ms. Jennifer Lacks Kaplan, my stepmother: Janet Shimer, and my grandfather: Dr. Sanford Lacks.