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