advanced cementitious composite development for resilient
TRANSCRIPT
Goal: To Develop Advanced Materials for Building 21st Century American Infrastructure
MotivationNeed to develop advanced construction materials as
Concrete Infrastructure: Lacks Durability & Sustainability
- 7% of the global GHG emissions (2009)- 10 times more energy intensive than average GDP in the US
Cement Plant
Lacks Resilience
ASCE’s Assessment of US Infrastructure
I-90 Truck Crash (2003) Japan Tsunami (2011)
Research Approach
Integrated Structures-Materials Design Framework (ISMD) – Li (2007)
Integrated Materials Design Framework for Sustainable Infrastructure (IMD-SI) – Keoleian et al (2006)
Multi‐scale Theoretical and Empirical Analysis
Experiments/Observations
Scal
e Li
nkin
g M
odel
-1
Scal
e Li
nkin
g M
odel
-2
Fini
teEl
emen
t Mod
elin
g
Life
Cyc
le M
odel
ing
Length Scale10-9 – 10-6 mnano-micro
Microstructure
10-6 – 10-3 mmicro-mesoSingle Crack
10-3 – 100 mmeso-macro
Composite Material
100 – 103 m
Infrastructure
103 – 106 m
Environment
Modeled Behavior
To understand and design a resilient and sustainable infrastructure, the material behavior down to nano-micro length scales is investigated using carefully designed experiments.
Based on the micromechanical tailoring of GHSHDC, the performance of infrastructure in terms of its resilience and sustainability is predicted using a series of analytical and numerical models.
Ductility CriteriaSingle Fiber Pullout
0
15
0% 4%
Stre
ss (M
Pa)
Tensile Strain Source: Chin (2006)
Fiber
Matrix Multiple Cracking in HSHDC
σ
δ
σLargest Concrete Arch
Bridge in North America
Hoover Dam Bypass Bridge
18% 17%
70% 80%
0%
50%
100%
GlobalWarmingPotential
Total PrimaryEnergy
End of life TrafficDistribution ConstructionMaterials
6.2 mil kg CO2
82 Tera-Joules
Bridge Deck LCAImpact AnalysisUniaxial Tension Modeling
Results so far …Invention of High Strength High Ductility Concrete
(HSHDC) [US Patent Pending]
Flexing of an HSHDC beam with NO steel reinforcement [short (1/2 inch) Polyethylene (PE) fibers (30 μm dia) used Vf = 2%]
Property HSHDC Concrete
Compressive Strength (MPa) 166 40Ultimate Tensile Strength (MPa) 14 3
Tensile Strain Capacity 3.50% 0.01%Modulus of Rupture (MPa) 30 4Average Crack Width (μm) 110 Indefinite
CO2 Footprint (kg CO2 eq/L) 0.88 0.30Primary Energy Intensity (MJ/L) 7 1.2
Composite Properties of HSHDC
Conclusions and Future Work• HSHDC shows excellent composite ductility in
spite of a very brittle high strength matrix. Such performance is enabled by the micromechanics based synergistic design of fiber, matrix, and interface of HSHDC.
• Future work involves high rate (up to 10s-1
strain rate) investigation of HSHDC and retailoring of the material to maintain the mechanical performance under extreme loading conditions such as earthquakes, hurricanes, impacts, and blasts.
• Identification and testing of viable green material alternatives to replace mainly fibers and cement in HSHDC for developing Green High Strength High Ductility Concrete.
• The end result of this research will be the development of Green High Strength High Ductility Concrete with extreme strength, ductility, durability, and environmental greenness required for a resilient and sustainable 21st Century Infrastructure.
Environmental Greenness & Durability
< 0.45 kg CO2 eq/Liter< 100 μm crack width
Tensile Ductility
> 3% (100 times that of concrete)
Compressive Strength
> 200 MPa (5 times that of concrete)
Proposed Material SolutionGreen High Strength High Ductility Concrete
Integrating strength, ductility, durability, and greenness in one concrete material
Green High Strength High Ductility Concrete
(GHSHDC)
Design Challenges:• Synergize material design philosophies• Trade-offs between mechanical and environmental performance• Reliable material performance under most extreme loading
conditions
Advanced Cementitious Composite Development for Resilient and Sustainable Infrastructure
Ravi Ranade & Victor C. LiDepartment of Civil and Environmental Engineering, University of Michigan Ann Arbor
Northridge EQ (1994)