survivable structures - transportation research...
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Office of Naval ResearchShip Systems and Engineering Div. Code 331
Distribution Statement A: Distribution Unlimited
Survivable StructuresSurvivable Ship Structures
Ship / Vehicle Protection Systems
Presented to
Committee on Naval Engineering in the 21st Century
Roshdy George S. Barsoum
Survivable StructuresOBJECTIVE: •Hybrid Composite and Metallic Hulls – Survivability, Affordability, Stealth, Strength, Durability and light weight for combatants and high speed ships. •Lighter/ cheaper platform and personnel protection system/armor, which defeats several threats – Polymer Coatings.
TECHNICAL CHALLENGES- Steel-to-Composite Joints critical part-solution at hand.- Scaling of test results and properties of adhesives under shockSimulation: Multi-scale Methods in Ship UNDEX WhippingTesting/ Verification: sea Loads and fatigue of a hybrid Hull- In-situ measurements at extreme loading and rates- Mechanisms in high strain rate under UNDEX, Blast and Ballistics- Mechanisms in Polymers: strain rate sensitivity, suppression of shear localization, phase transformation (rubbery-glass transition)- Extremely high rates ( > 10E6 /Sec) - Molecular dynamics simulation of elastomers at extreme rates- Engineering of polymers-by-design. APPROACHTest scaled models of hybrid hull conceptsNew and conventional metallic to composite joints to achieve ductile failure under dynamic loadingUnderstand sea loads and fatigue and UNDEX Whipping behavior of Hybrid HullPerform tests at the threat level and use high speed photography- flash x-ray. SAXS and WAXS- Perform simulation to understand behavior.Experiments at max possible rates and use Time -Temperature superposition (relaxation theory) and high frequency - dielectric loss – at high pressure (molecular dynamic theory) – compression shear plate impact at very higher rates. Constitutive models and test models in simple ballistic and reversed ballistic experiments.
S&T productsStrength of Composite Hull following battle DamageHybrid Joint Structural ResponseDesign & Structural Response of Composite and Advanced Hull FormsEnergy Absorbing structuresFailure models/ simulation of UNDEX, AirEx, ballisticsOptimization methods for lighter/ cheaper EFP armor and protection systems for ships/ submarines.Design/Simulation capability for crew protection against shock and Traumatic Brain Injury TBI.Design capability of lighter Multi Functional Polymers for Survivability (protection/stealth).
Low Cost Composites for Complex hydro- dynamic shapes, result in reduced drag/resistance and improved performance and fuel efficiency
•Complex shapes for bow and stern can reduce Hydro Acoustic signature
•Signature: Non-Magnetic Materials
•Frame structure for Control of Acoustic Sig.
• Low-Cost Fabrication of Complex–Shaped Structure
•Lower Hull Whipping Stresses
•Shipyard Block outfitting DD-21 Hydrodynamic Model
Steel Hull / Composite Bow & Stern
Hybrid Ship Hull
Low cost Composite for Complex shapes
for Stern, Hull and Bow
result in large energy saving
Energy Saving through Lightweight Structures Low Cost Highly Efficient Hull Shape
R.G. Barsoum, 331
Sea Loads – Hogging and Sagging:Loaded 40% above ABS design load
Survivability after battle damage Blow out Panels to relieve Internal Explosion
Loaded up to design load no further yielding
Survivable Ship Structures
Fatigue- Large scale testing of Hybrid Hull 32500,000 cycles at 1.3 x design loadAdditional 317,000 cycles, cracks started to appear in composite panel. Repair welds and drill holes to stop crack propagation1.75 x design load: yield in steel and cracking in the adhesive at the steel to composite frame jointsExceed all ABS and Navy requirements.
Hogging and sagging of hybrid hull
6.5 Ft
Grenestedt/Lehigh
9 Blow out panels
UNDEX Whipping comparison of Conventional Steel Hull and Hybrid Hull –
Same displacement and MultDouble the factor of safety
of Conventional Hull
Fluid (sea water)
Composite panelPoint mass
x
z
y
Hybrid HullWhipping
x
z
Draft
d
W
Lua, U Maine
Cohesive elements
Bubble Pulsation
DDG typeConventional Steel Hull
US-Japan Cooperative Research Advanced Hull Materials & Structures Technology
High Pressure Tank
Rupture Disk
Test Plate
Test Fixture
DynamicPressureLoading
Kamioka
test pond
SUS
CFRP
UNDEX Hybrid Joint
UNDEX Aberdeen Test pond
Full Scale Buckling Hybrid Joint
Hybrid Hull
UNDEX/TRDI/Japan
NSWCCD
Joints
US -GRPBoth Failed in GRP section
Japan-CFRP Both failed in CFRPNo failure at Joint
v ~ 2620 m/s ~ +2.1csH ~ +1.3cl
H
20 mmv ~ 2620 m/s ~ +2.1csH ~ +1.3cl
H
20 mm
Composite-to Metallic Joint MechanicsFriction, De-cohesion Models, Fracture, Multi scale & Scaling Laws
BROWN U-Dynamic cohesion/ decohesion and friction laws at Composite/ steel interfaces
Rosakis (Caltech) Test dynamic friction at composite to steel interface
To instronin train E-glass
beam
Stainless Steel
V. Gupta/UCLA Rice (Harvard)- Dynamic FrictionCoulomb Law is ill-posed, no unique answerClifton (Brown)-New Dynamic friction Law- rate dependence
Fish, RPI Multi scale
TWI/UK Sculpted steel surface
Friction
SS to composite Adhesive
Scaling LawsBazant/Northwestern
1 10 100
100
size
Strength
Slamming load facility-Lehigh U.
Composite panels
Speeds up to50 Knots
Hydro-elastic effects
Explosion Resistant Coating (ERC)Light armor against IEDs
USMC CougarRoute vehicles
Energy saving through Lightweight Ship Protection System and Armor
Explosion Resistant Coating (ERC) Lightweight Ship protection
Blast Loading /UNDEX
R.G. Barsoum, 331Uncoated Coated
Elastomer-Retardation of Necking and shear localization in Steel – subject to blast loading
Hutchinson/Harvard
Ortiz (Caltech)3-D simulation-
cohesive elements for steel and phenomenological constitutive model –(Penetration mechanics)
Shear Localization suppression by Elastomers
Fish (RPI)Multi scale simulation modules compatible with commercial finite element code architecture (3-D effects, material studies)
Belytchko (NorthWestern)Meshfree
Methods for Polyurea
XFEM to Model Cracking in Shells
Enhanced elements for shear band modeling(UNDEX-AirEx)
ERC
Quadratic cohesive cohesive
LawElement
Elastomer
Absorbs >50% of Energy
Shot 725
Tests by Mock NSWCDD
Roland/NRL, Mock/NSWCDD, Balizer/NSWCCD
P1000
P650
P250/1000
SAXS
Edge Centerof Impact
(in collaboration with Prof. K. Weinberg, Universität
Siegen, Germany):
Failure Theory for Elastomer
at high rate loading Michael Ortiz (PI), Caltech
•Implemented, validated, calibrated time/temperature shift model•
Implemented, validated, calibrated
Prony
series into PU material model•
Implemented pressure-shear void
growth model of ductile rupture•
Conducted validation runs of NSWC
(Dahlgren) rod-impact experiments
Simulations of Taylor-anvil rod-impact test of PU (shot 856, Courtesy W. Mock,NSWC)
Ave. Pressure Range in
Polymer2000‐4000 Mpa(290‐580 ksi)Strain Rate > 10E6/sec
Extremely High Strain rates and pressureat very high impact velocity
Polymer Constitutive Models are extrapolated from Hopkinson B, Pressure Shear Plate Impact and Time-Temperature relaxation Curve Computational MethodsLagrangian (ABAQUS/Autodyn/DYNA)Arbitrary Lagrange-Euler (ALE)(DYSMAS)Smooth particle Hydrodynamics (SPH)-CTH
Tech.Challenge:In-SituMeasurement
0
0.02
0.04
0 .06
0 .08
0 .1
0 .12
0 .14
0 .16
0 .0 0 .2 0 .4 0 .6 0 .8 1 .0 1 .2E ffective S tra in
Effe
ctiv
e St
ress
(GPa
)
barp4: U nconfined S P H B (U C S D )
puc11c: C onfined S P H B (U C S D )
404: P S P I (B rown)
501: P S P I (B rown)
502: P S P I (B rown)
3.0GPa, 2.4×105s-1
2.5GPa, 1.88×105s-1
2.4GPa, 2.4×105s-1
0.47GPa, 3×103s-1
0.23GPa, 3×103s-1
0.006GPa, 6.2×103s-1
0.013GPa, 6.2×103s-1
Current conflicts have seen a dramatic increase in Traumatic Brain Injury (TBI), due to improvement in body armor and higher soldier survivability from fragments and other lethal injuries. Tests and theoretical developments on polymers (Explosion Resistant Coating), indicate that these polymers can provide the necessary protection against TBI. Collaboration with Codes 30, 332, 34 ARO and JIEDDO.
Objectives:
Basic Research Challenge: Elastomeric polymer–by-design for protection warfighter against Traumatic Brain Injury (TBI) by diverting and dissipating blast induced shock waves form the head.
Approach
Building on successful test results on “Explosion Resistant Coating” for ship and vehicle protection, ONR is leading a Basic Research Challenge to develop polymers-by-design to divert and dissipate shockwaves from the head and thus prevent Traumatic Brain Injury - TBI. Tests and theoretical developments on polymers, indicate that these polymers can provide the necessary protection against TBI.
– Recent investigations into blast resistant properties of polyureas and other multi-phase polymeric elastomers indicate that they can dissipate broad bands of frequencies such as those in blast events.
– Polyurea polymers have been shown to absorb shock in quite a different manner than any ballistic material known to the armor community.
Provide lightweight polymers, which divert and dissipate the shockwave from the head, in addition to improving the ballistic, blast and impact performance of the helmet material and thus prevent Traumatic Brain Injury – TBI.
SEPT 2009
POLYMER–BY-DESIGN FOR PROTECTION AGAINST TRAUMATIC BRAIN INJURY
POLYMER–BY-DESIGN FOR PROTECTION AGAINST TRAUMATIC BRAIN INJURY
Mo lecula r scale
33WW CC NN TT
έ
LFT - NSWCCD
optimization
Continuum Simulation
Polymer Synthesis
UCSD, Penn State, MIT