Mixed type binding systems. A sustainable alternative for RCC
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Transcript Mixed type binding systems. A sustainable alternative for RCC
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Mixed type binding systems. A sustainable
alternative for RCC Pavements
I. Papayianni, E. Anastasiou, M. Papachristoforou
Laboratory of Building Materials
Aristotle University of Thessaloniki
Greece
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Background
Binders are the most precious materials in building construction, since they
transform a volume of grains into a compact, load-bearing material of adequate
volume stability
Portland cement is an excellent high-strength binder which predominates in
construction, but is also an energy consuming, high-cost material of low
ecological profile
Under the pressure of reality:
Climatic changes and catastrophes
Global economic depression
Need of longer service life for constructions
There is an urgency to develop alternative smart mixed type binding systems
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Background
A first simple step for sustainability integration in construction is to make local
industrial by-products (fly ashes, slags) beneficial for the structural sector
How do we work to exploit industrial by-products to the maximum:
Test the suitability of the by-products as cementitious materials for a specified use
Development of a mixed type binding system and assessment of its quality
Design and proportioning of a proper concrete mixture for a specified strength
Test the compliance of the concrete with a control mixture
Proceed to a pilot application of the designed concrete
Measure the concrete performance and the long term characteristics on site
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
The construction of a RCC road pavement with a
fly ash-based binding system
Stakeholders:
Aristotle University of Thessaloniki (responsible for research and consultancy)
National Technical University of Athens
TITAN Cement Industry
EGNATIA ODOS S.A.
TERNA Construction Company
Project:
TEFRODOS 2011-2014
Funds:
General Secretary of Research and Technology, Greece
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
The construction of a RCC road pavement with a
fly ash-based binding system
In Greece, only asphaltic concrete has been used for road pavements
There is no tradition in bedding concrete road pavement
The RCC pavement alternative seems to be the most feasible solution
The main advantages for such a solution are:
Longer service life and lower cost of maintenance
Reduced environmental footprint
600000
kg CO2-eq
500000
400000
Recycling & disposal
300000
Maintenance
200000
Construction
100000
0
Asphalt pavement
Concrete pavement
Global Warming Potential over 100 years
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
The construction of a RCC road pavement with a
fly ash-based binding system
Stronger and resistant to heavy truck circulation
(RCC pavements are recommended for interchange ramps and heavy truck
traffic in hot climates)
Reduction of thermal emissions
Light reflectivity
Infrared photgraphy of the Atlanta
Hatfield Airport (property of
NASA) where asphalt parking lots
develop higher temperature
compared to concrete parking lots
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
The construction of a RCC road pavement with a
fly ash-based binding system
The initial construction cost of a concrete road is slightly higher than that of
Cost(€/m2)
asphaltic concrete
By using fly ash-based hydraulic binders the cost is significantly reduced
50
45
40
35
30
25
20
15
10
5
0
Initial construction cost (€/m2)
041
041
Asphalt pavement
Concrete pavement
046
Concrete pavement with
asphaltic anti-skid layer
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Development of the mixed type binder and quality
assessment
Aim: 28-d compressive strength of 40 MPa, so as to have on site at least 30 MPa
Materials (% by mass)
Calcareous fly ash 50%
Clinker 25%
Natural pozzolan 12.5%
Limestone filler 12.5%
Test measurements:
Blended mixed type binder
Testing according to EN 13282 for Hydraulic
Road Binders
Fineness
Grinding time
Water demand
Setting time
Le Chatelier volume stability
Compressive strength at 2, 7 and 28 days
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Characteristics of the constituents of the hydraulic
binder developed
Cement
clinker
Calcareous fly
ash
Limestone
filler
Natural
pozzolan
SiO2 (%)
21.35
34.40
0.20
63.80
Al2O3 (%)
5.40
13.60
0.20
18.10
Fe2O3 (%)
3.40
6.10
0.05
4.10
CaO (%)
65.75
32.80
55.00
2.80
MgO (%)
1.60
3.80
0.60
1.00
CaOfree (%)
1.30
6.40
n/a
n/a
SiO2-reactive (%)
n/a*
n/a
n/a
35.00
SO3 (%)
1.20
6.78
0.00
0.00
L.O.I. (%)
0.00
3.26
44.10
3.20
Insoluble residue (%)
0.00
23.80
0.00
82.80
Content/ Property
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Properties of the produced mixed type hydraulic binder
Physical properties
Blaine (cm2/g)
9550
Fineness (retained at 45 μm)
0.4
Water requirement (%)
41.5
Initial setting time (min)
210
Le Chatelier dilation (mm)
0.0
2-day compressive strength (MPa)
15.9
7-day compressive strength (MPa)
26.3
28-day compressive strength (MPa)
40.1
Chemical properties
L.O.I. (%)
SO3 (%)
Insoluble residue (%)
CaOfree (%)
Chemical analysis
SiO2 (%)
Al2O3 (%)
Fe2O3 (%)
CaO (%)
MgO (%)
Laboratory of Building Materials - Aristotle University of Thessaloniki
8.40
3.20
26.40
4.80
29.90
12.65
3.80
42.90
2.20
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Proportioning RCC with fly ash-based hydraulic binder
“Tefrocement”
Required strength: fck C25/30
Maximum Vebe density (according to ACI 325.10R-95) with Vebe time: 20-40s
Available aggregates: Crushed limestone of maximum size 31.5 mm or 16 mm
“Tefrocement” quantity: ≤ 300 kg/m3
Water/cementitious ratio: ≤ 0.50
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
The proposed aggregate gradations
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Trial mixes series A and B
Mixture
Hydraulic Road Binder (kg/m3)
Water (kg/m3)
Fine aggregate (kg/m3)
Coarse aggregate (kg/m3)
Max. aggregate size (mm)
A1
280
153
1096
897
16
A2
280
153
1096
897
16
A3
280
196
1096
897
16
A4
280
163
1096
897
16
B1
300
120
1096
897
31.5
B2
270
135
1096
897
31.5
B3
280
150
1096
897
31.5
B4
280
148
1096
897
31.5
superplasticizer (%wt. of binder)
w/cem
Vebe time (s)
Vebe density (kg/m3)
Electrical hammer density
(kg/m3)
7-d compr. strength (MPa)
0.0%
0.54
2427
1.0%
0.54
2396
1.0%
0.70
20
2428
0.0%
0.58
60
2410
1.0%
0.40
8
2396
1.0%
0.50
9
-
1.0%
0.54
60
2389
0.5%
0.53
35
2404
2480
2355
2446
2447
-
-
2408
2478
33.5
28.3
22.4
32.4
-
22.0
28.6
31.1
28-d compr. strength (MPa)
43.8
35.7
30.9
46.0
35.4
35.3
37.5
42.3
Decision to use 280 kg/m3 “Tefrocement”
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
New series of laboratory test mixtures
series A and B, accounting for transport time
Mixture
Hydraulic Road Binder (kg/m3)
Water (kg/m3)
Fine aggregate (kg/m3)
Coarse aggregate (kg/m3)
Maximum aggregate size (mm)
superplasticizer (%wt. of binder)
w/cem
Vebe time (s), t=0'
Vebe time (s), t=30'
Vebe density (kg/m3), t=0'
Vebe density (kg/m3), t=30'
A5
280
148
1096
912.6
16
0.0%
0.53
60
100
2385
2420
A6
280
148
1095.8
912.6
16
0.5%
0.53
40
80
2313
2410
B5
280
159
1095.8
629.2
31.5
1.0%
0.57
12
30
2430
2415
B6
280
148
1096
629.2
31.5
0.0%
0.53
50
80
2447
2400
Electrical hammer density (kg/m3), t=0'
2474
2505
2466
2490
7-d compressive strength (MPa)
28-d compressive strength (MPa)
31.4
45.6
30.7
43.4
25.5
37.9
33.7
49.3
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Pilot construction
Ground layer with CBR ≥ 18
Concrete plant at 30 minutes driving distance
Continuous feeding of the paver
Compaction achieved by rollers
Measurement of compaction with Humboldt nuclear gauge
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Truck loading
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Truck unloading onto paver
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Difficulty unloading truck due to delay in transportation
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Laying RCC
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Laying RCC
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Roller compaction of pavement
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Fresh concrete density measured with nuclear gauge
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Achieved compaction
Only with the paver, the compaction achieved was 80%
depth
directly after the paver
after compaction
5 cm
81.8%
90.4%
10 cm
81.2%
91.3%
15 cm
81.0%
90.6%
20 cm
79.7%
89.3%
average total pavement
thickness (cm)
-
22.1
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Effective compaction scenarios
3 non vibrating passes with a 4 ton roller
2 vibrating passes with a 10 ton roller
Maximum single layer thickness achieved: 20 cm
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Joints
Shrinkage joints: cut every 5.5-6.0 m after hardening, to a depth corresponding
to 1/4 - 1/3 of the road thickness
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Joints
Thermal dilation joints
Source: Cement and Concrete Association of New Zealand, "Concrete ground floors and pavements", Part 1
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Survey of concrete pavement 2 months after construction
Core drilling and testing
Mechanical properties
Freeze-thaw resistance (-25°C to +20°C)
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Survey of concrete pavement 2 months after construction
Mechanical properties of drilled cores
Construction area (average of 6)
1
2
3
pulse velocity u (m/sec)
4625
5022
4713
density ρ (kg/m³)
2295
2394
2345
Compressive strength fc (MPa)
25.0
32.0
31.8
Continuous monitoring of the test road
Laboratory of Building Materials - Aristotle University of Thessaloniki
V International Conference ASHES FROM TPPS – Removal, Transport, Processing, Storage
April 23-25, 2014, Moscow
Conclusions
The construction of a RCC road with this mixed type binder is feasible
The technical problems that appeared were properly confronted
The long term strength and resistance were adequate in order to guarantee a
long service life
The incorporation of a low cost industrial by-product into a hydraulic binder
contributes essentially towards lowering the initial cost of a concrete road,
rendering this sustainable alternative also cost-effective.
Laboratory of Building Materials - Aristotle University of Thessaloniki
Thank you for your attention!
Laboratory of Building Materials - Aristotle University of Thessaloniki