Overview UCSD Structural Engineering Aerospace Structures and ... · PDF fileDepartment of Structural Engineering Overview UCSD Structural Engineering Aerospace Structures and Composites

Department of Structural Engineering

Overview

UCSD Structural Engineering

Aerospace Structures and Composites

Aviation Safety Center

AIAA Structures TC Mid Year Meeting

Thursday, September 11, 2014

Department of Structural Engineering About UCSD Structural Engineering

• Structural Engineering (SE) Dept. formed

in 1995

• Spinoff from Applied Mechanics and

Engineering Sciences (AMES)

• Unique program in U.S. dedicated

entirely to structures and structural

mechanics

• Focus on all types of structures:

• Aerospace, marine, wind energy,

biological, civil structures and

earthquake engineering, geotechnical,

etc.

• Experimental evaluation - static and

dynamic, numerical methods and fluid-

structure interaction, structural health

monitoring

Department of Structural Engineering SE Numbers

Faculty

• 21 Professors

• 1 Lecturer

• 2 Adjunct Professors

• 3 Emeritus Professors

Space - 5 Sites

• Structures and

Materials Building

• Offices, labs

• Powell Structural

Systems Lab

• Powell Structural

Components Lab

• SRMD Test Facility

• Englekirk Research

Center (off campus)

Englekirk

Research Ctr.

(~10 mi. East)

Structures & Materials

Engineering

Bldg

North

Lab

SRMD Facility

Department of Structural Engineering Undergraduate Program

• 4-year program leading to Bachelor of Science degree (ABET accredited Structural

Engineering program)

• Enrollment: 650 students

• Approximately 80-110 graduate per year (total enrollment increasing)

• Students choose a Focus Sequence specializing in:

• Aerospace Structures

• Renewal of Structures

• Civil Structures

• Geotechnical Engineering

• Coursework relevant to Aerospace and Composites area (in addition to core courses on

solid mechanics and structural analysis)

• Finite Element Analysis (SE131)

• Design of Composite Structures (SE142)

• Aerospace Structures (SE160A, B)

• Nondestructive Evaluation (SE163)

• Aerospace Structures Repair (SE171)

• In senior year, students can take graduate-level courses in Composite Mechanics

(SE253A, B, C), Structural Stability (SE202), Experimental Mechanics and NDE

(SE252), Structural Health Monitoring (SE265), Polymers and Composites (SE251B)

Department of Structural Engineering Aerospace Structures Curriculum

Year Courses

Freshman Math, Physics, Chemistry, General Education

SE1. Intro to Structures and Design

SE2. Structural Materials

Sophomore Math, Physics, General Education

SE9. Algorithms and Programming for Structural Engineering (MATLAB)

SE101A, B, & C. Statics, Dynamics, Structural Dynamics

SE102. Numerical, Computational, & Graphical Tools (CAD: Solidworks)

SE110A & B. Solid Mechanics I and II

Junior General Education, Technical Electives

SE103. Conceptual Structural Design

SE115. Fluid Mechanics

SE121. Numerical Methods

SE130A & B. Structural Analysis I and II

SE160A. Aerospace Structural Mechanics I and II (FE: PATRAN / NASTRAN)

Senior General Education, Technical Electives

SE120. Engineering Graphics and Computer Aided Structural Design.

SE125. Statistics, Probability, & Reliability

SE131. Finite Element Analysis

SE140. Structures and Materials Laboratory – Capstone Design Course

SE142. Design of Composite Structures

SE171. Aerospace Structures Repair

Department of Structural Engineering UCSD Powell Lab

Key feature of Department is the Powell Lab:

• World-class, large-scale, multiple-location, multi-

million-dollar facilities

• Dedicated to research at the materials-, component-,

assembly-, and systems-levels

• Offers unique capabilities - e.g., simulating blast

impulse, 12M lbs load test machine

Department of Structural Engineering Large-Scale Dynamic Test Machine

Department of Structural Engineering Blast Simulator Facility

Technical Specification for a Blast Generator:

Operating pressure: 350 bars

Maximum force: 70 tons

Dynamic stroke: 1.15 m

Maximum velocity w/mass:

100 kg => 66 m/s 200 kg => 55 m/s

400 kg => 43 m/s 800 kg => 32 m/s

Department of Structural Engineering Blast Simulator Facility

Blast Simulator Configuration

4 BG25 and 2 BG50 blast generators in multiple

arrangements

Impact Velocity Range

1 to 30 m/s (3.2 to 98.4 ft/s) (BG25)

Up to 66 m/s (216.5 ft/s) (BG50)

Test Impulse Range

Widely variable, 0.7 to 24.1 MPa-msec

(100 to 3500 psi-msec) (BG25)

Up to 82.7 MPa-msec (12,000 psi-msec) (BG50)

Test Specimens (As-built and retrofit)

Walls: CMU, URM, curtain, blast

Blast panels

Columns: RC, steel

Transportation structures: piers, decks

Windows

Military systems and components

Left: As-built reinforced concrete

column after 1500 psi-msec impact.

Column is no longer structurally

sound.

Right: CFRP wrapped retrofit

reinforced concrete column after

1500 psi-msec impact. Column is still

structurally sound.

Above: Unreinforced masonry (URM)

wall at 5, 35, 65, 95, and 125 msec

after 150 psi-msec blast simulator

impact. Structural response

progression captured by high speed (up to 10,000 fps) Phantom cameras.


• UCSD established Composites Aviation Safety Center

• Multi-disciplinary scope bridging small to large length scales

• UCSD is member / active participant in:

• FAA Joint Advanced Material and Structures Center of Excellence, Member

Institution

• NASA California Space Grant Consortium – Lead Institution

• Composite Materials Handbook 17 (formerly Mil-Hndbk-17)

• ASTM Working Group on UAVs

• National & International Societies: American Inst. for Aeronautics & Astronautics,

American Society for Composites, International Committee on Composite Materials

Composites Aviation Safety Center

Basic & Applied

ResearchStatic & Dynamic

Structural Tests

FAA Certification

Tests

Materials

Processing &

Characterization

Dynamic

Response

Simulation

Impact Damage

UCSD Composites

Aviation Safety Center

Damage Tolerance

NDE & SHM

Department of Structural Engineering Faculty Related to Composites

Prof. John

Kosmatka

Design, analysis, and experimental testing of light-weight advanced

composite structures, dynamic response and vibration, UAVs.

Ae

rosp

ace S

tructu

res a

nd

Com

po

sites

Prof. Hyonny

Kim

Impact effects on composite materials and structures with aerospace and other

applications, blast response, nano- and multifunctional-materials, and adhesive

bonding.

Prof. Chiara

Bisagni

Buckling and post-buckling, crashworthiness, fatigue, damage propagation,

optimization of aerospace composite structures using nonlinear analysis and

structural testing.

Prof. Yu Qiao

High-performance infrastructure materials, smart materials and structures,

energy-related materials, failure analysis for engineering materials and

structures. Ma

teria

ls,

Po

lym

ers

Prof. Michael

Todd

Structural dynamics, nonlinear vibrations, time series modeling, structural

health monitoring strategies for civil, mechanical, and aerospace systems, fiber

optic sensor system design and noise propagation modeling.

ND

E &

SH

M

Prof. Francesco

Lanza di Scalea

Health Monitoring, Non-destructive Evaluation and Experimental Mechanics of

Structural Components using novel sensing technology.

Prof. David

Benson

Computational mechanics and computer methods for solving problems in

mechanical engineering.

Co

mp

uta

tion

al

Me

ch

an

ics

Prof. Yuri

Bazilevs

Design of robust and efficient computational methods for large scale, high

performance computing.


• Vehicle Model Development

• Material Qualification

• Structural Testing

• Ground Vibration Testing

• Flutter Speed Prediction

• Flight Testing Correlation

Researc

h o

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Ko

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atk

a

Ground Vibration Testing

Innovative Ground Vibration Testing Techniques for Unmanned Aircraft

• General Atomics, Northrop-Grumman


• Using embedded piezo-patches and acoustic emissions to

detect fiber and/or matrix failures

• 1/3 scaled wings for lab testing

• Prognosis based upon probabilistic loads and structures

(Co-PI Professor Joel Conte, SE)

Fuselage Panel

Structural Health Monitoring

Structural Health Monitoring and Prognosis of Composite Aircraft

• LANL, General Atomics, NASA-Dryden

Researc

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Wind Tunnel Testing

V/RTM Fabrication

Flight Testing

Plume Monitoring

Unmanned Aircraft

Innovative Unmanned Aircraft Development for Science Missions

• NSF, LANL, NASA, Northrop Grumman

Researc

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Department of Structural Engineering VaRTM Infusion

Flow Mesh

• UCSD developed

fabricated testbed

• 29-meter length

• 100-ton vehicle

Composite Bolted

Joint 233,000 lbs

Flow Distribution Mesh

Vacuum (Outlet) Lines

Inlet 1

Preform

Resin supply

Vacuum pump Resin trap

Inlet 2

Flow Spring

Multiple Inlets

• 3-D Flow Sim

Proof Testing

316,000 lbs

M1-A1 Field

168,000 lbs

Stiffeners

VaRTM Infusion Strategies for Large-Scale

Low-Cost Composite Structures

• Office of Naval Research, US Army, BAE

Researc

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Ko

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atk

a


Landing Gear Braces - keeps gear locked open

imag

e fr

om

: mo

ney

.cn

n.c

om

image from www.messier-dowty.com

UCSD has conducted FAA Certification Tests required

for these components to being flown on the B787

Carbon/Epoxy

composite

braces required

to withstand

over 1 million

lbs load.

Test at UCSD SRMD Facility

Certification Testing

Certification Testing of Boeing 787 Landing Gear Braces

• Messier-Dowty

Researc

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rof.

Kim


Blunt Impacts

• Threat sources that act

over wide area or

multiple structural

elements

• Damage produced can

show little or no exterior

visibility

Blunt Impact Damage to Aircraft

• Federal Aviation Administration + Industry Collaboration (Boeing,

Airbus, Bombardier, Cytec, United Airlines, Delta Airlines, San Diego

Composites)

Hail Ice Impact• upward & forward facing

surfaces

• low mass, high velocity

Ground Vehicles &

Service Equipment• side & lower facing

surfaces

• high mass, low velocity

• wide area contact

• damage possible at

locations away from

impact

Researc

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rof.

Kim

Researc

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rof.

Kim


Shear Ties (25)

Skin

Stringers (4) – Co-Cured With Skin

Frames (5)

2 m

1.8 m

F

~6-8 ft. WideBumper

ContactAcrossSeveralFrames

“Steady State”Zone

TransitionZone

Full BarrelIdealization

Fuselage Impact by GSE

Frame + Stringer

Specimen

- loading across

middle 3 frames

Post-Test

Photo

Underside

Damage

Researc

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rof.

Kim


Damage Modes

Sandwich Panel Impact - 1st facesheet penetration FE Simulation – projectile model

High Speed Video Stills of 61.0 mm Ice at 62 m/s

Highest forces generated early – damage occurs in target

High Velocity Ice Impact

High Velocity Ice Impact Damage to Composites

• FAA, Avanti Tech/Air Force, Industry Projects

Researc

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rof.

Kim


Develop test methodology for quantitative

measurement of blast impulse absorption

evaluate/rank armor panel designs

Tile array applies impulse to flexible target

equivalent to mine blast charge

Vehicle Armor Panels

Investigation of Vehicle Armor Panels for Blast Protection

• Armorworks / US Navy

Researc

h o

f P

rof.

Kim


Unstiffened cylinders: buckling

load and post-buckling field

(DEVILS - FP4)

Stiffened cylinders: post-

buckling field and collapse

(POSICOSS - FP5)

Curved panels: cyclic

buckling and pre-damage

(COCOMAT - FP6)

Fast tool for analysis and

optimization

(MAAXIMUS - FP7)

www.maaximus.eu

Aircraft structures: dynamic

loads and damping

(DAEDALOS - FP7)

www.daedalos-fp7.eu

Launchers structures: single load

perturbation and stochastic analysis

(DESICOS - FP7)

www.desicos.eu

Buckling of Composite Structures

Researc

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rof.

Bis

ag

ni


Stiffened Panel Stiffened Panel

Single Stringer

Compression

Specimen

• The Single Stringer Compression

Specimen (SSCS) is sized such that its post-

buckling response and its damage tolerance

are representative of the stiffened panel.

• The SSCS allows the use of detailed finite

element analyses that account for

intralaminar and interlaminar damage

mechanisms, and to minimize the complexity

and the cost of the experimental tests.

• The sequence and relative importance of

post-buckling, delamination, intralaminar

failures is studied, as well as the residual

strength due to a Teflon insert, and the

fatigue behavior.

Damage Tolerance

Researc

h o

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rof.

Bis

ag

ni Front VIC-3D

Infrared camera SSCS

In-Situ UT Scanner

Rear VIC-3D

Department of Structural Engineering Fast Tool for Analysis & Optimization

Elastically restrained

panel (closed form)

Plate assembly

model

Compression

Compression

and shear

Orthotropic

Symmetric and

balanced

Formulation Loading condition Lay-up Results

Buckling load

Initial post-buckling

Stress distribution

Design charts

Buckling load (refined)

Elastically restrained

panel (semi-analytical)

Compression

and shear Balanced

Buckling load

Post-buckling

Stress distribution

Genetic Algorithm

YESNO

Population

Fitness

Genetic

operators

Technological

constraints

Structural

weight

Pre-buckling

stiffness

Buckling

load

Analytical

formulation

First ply

failure

Convergence? End

Structural requirements

Post-buckling

stiffness

Analytical Abaqus

Homogeneous

solution

Particular

solution

Compatibility

equation

Buckling

load and mode

Boundary

conditions

General

solution

Equilibrium equation

Post-buckling out of plane

displacement

Post-buckling stiffness

Galerkin solution

Results

Exact solution

Stress distribution

Researc

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Department of Structural Engineering Textile Composite Materials

Elastic properties of

glass fiber and polypropylene

3D Mosaic

Stiffness matrices of weft, warp

and loop yarns

3D Mosaic

Elastic properties of

the textile composite

YARNSTEXTILE

RVE Simplified RVE

Switch between the actual

geometry to an equivalent

model in terms of elastic

properties

3D Mosaic model of the RVE

RVE of the textile

Researc

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Bis

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Tearing mode

Microfragmentation

mode

Socking mode

Splaying mode

• Study the energy

absorption of

composite

structures

• Investigation

carried out starting

from simple

specimens to more

complex structures

• Integration of

numerical and

experimental

activities

Crashworthiness

Researc

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rof.

Bis

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ni

Department of Structural Engineering Ditching and Impact on Water

• Small scale drop tower and pool for experimental

investigations of ditching and impact on water

(preliminary design)

• Design and manufacturing of scaled deformable

models

• Improvements of numerical modeling

capability (FEM and SPH) in case of vertical and

angled water impact

• Extended experimental validation on different

scaled models configurations

LS-DYNA analysis of an aircraft model

ALE and Lagrangina+SPH

Researc

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Bis

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Documents

Overview UCSD Structural Engineering Aerospace Structures and ... · PDF fileDepartment of Structural Engineering Overview UCSD Structural Engineering Aerospace Structures and Composites