DAY 4

LOAD FACTOR

L=W L+L=W+F

LOAD FACTOR :

A factor which defines load in terms of weight

W

L

g

An

11

zAg

WF L

g

AW z1LL

V-n DIAGRAM

SIGN CONVENTIONS

C) BENDING MOMENTB) SHEAR FORCEA) AXIAL FORCE

F) ANGLE & ROTATIOND) TORQUE E) SHEAR FLOW

SIGN CONVENTIONS (REACTION LOADS)

A) AXIAL & SHEAR

C) TORQUE

B) BENDING MOMENT

EQUILIBRIUM OF FORCES• THE FORCE EQUILIBRIUM EQUATIONS ARE

0

0

0

M

F

F

Y

X

STRUCTURE

FREE BODY DIAGRAM

PL

1200 lb40000 lb-in

W=8000 lb

A BC T

lb 1200

0

T

Fx

506P

0067 15P

400006*8000150*10*1200

0

P

M B

9447 L

8000

0

PL

FY

TRUSSTRUSSES ARE CLASSIFIED AS

- STATICALLY DETERMINATE- STATICALLY INDETERMINATE

32 jm m= Number of membersj= Number of joints

m 2j-3 Structure is unstablem 2j-3 Structure is statically indeterminate

TRUSSES (Contd…)• Identify whether the structure is statically

determinate / indeterminate

C

A B

RAH

RAV

RBH

RBV

P PPPPP

A B C D

TRUSS ANALYSIS

TRUSSES CAN BE ANALYSED BY- METHOD OF JOINTS- METHOD OF SECTIONS

SPACE TRUSS• The six equilibrium eqns are

0

0

0

Z

Y

X

F

F

F

0

0

0

Z

Y

X

M

M

M

RCosF

RCosF

RCosF

Z

Y

X

222zyX FFFR Resultant force

Component forces

Z

F

Y

F

X

F

L

R ZYX Geometric relation

LANDING GEAR

Resolving the forces in V direction

Resolving the forces in D direction

lbcos*F

F

AV

V

193161520000

0

lbsin*F

F

AD

D

51761520000

0

LANDING GEAR (FREEBODY DIAGRAM)

C.

..

.

... . H

A A

BB

C

FBH

FCG

19318 lb19318 lb

5176 lb

I

I

J

J

FJV

FIV

FJD

FID

FGV

FEDFES

FES

TE

TEFED

FEV

FEV

FIS

FGS

E

E

G

G

5176 lb

8"

3"

3"

20"

23"

44"

45

V

D

S

LANDING GEAR (FORCE ESTIMATION)

A

B

C

FBH

FCG

19318 lb

FEDFES

TE

FEV

in-lb 41408

08*5176

0

E

E

EV

T

T

M

V

D

S

lb 14003

03*)45(*20*)45(*44*5176

0

BH

BHBH

ES

F

SinFCosF

M

lb 11370

020*)7.33(*3*)7.33(*8*19318

0

CG

CGCG

ED

F

SinFCosF

M

lb 19760

45 Cos 7.3319318

0

EV

BHCGEV

V

F

FCosFF

F

lb 4730

45 Cos 5176

0

ED

BHED

D

F

FF

F

5176 lb

56.3

45

lb 6309

33.7Sin

0

ES

CGES

S

F

FF

F

LANDING GEAR (FORCE CALCULATIONS)

I

J

FJV

FIV

FJD

FID

FCG=11370 lb

FES=6309 lb

TEFED=4730 lb

FEV=19760 lb

FIS

E

G

00 ISS FF

lb 1361-

203*4730

0

JD

JDE

IV

F

FT

M

lb 6091

13614730

0

ID

ID

D

F

F

F

lb 12109

*202*)7.33(*18*)7.33(*3*19760

0

JV

JVCGCG

ID

F

FSinFCosF

M

lb 17110

7.3319760

0

EV

JVCGIV

V

F

FCosFF

F

WING STRUCTURES

WING STRUCTURES (FREEBODY DIAGRAM)

FAZ

FAY

FGZ

A

C

G

60”

100”

180”

16 lb/in

lb 2592

90*180*16*100

0

GZ

GZ

A

F

F

M

FRONT SPAR

Using Geometric relation

lbFGY 4320100*60

2592

lb 288

2592180*16

0

AZ

AZ

Z

F

F

F

FGY

Z

F

Y

F

X

F

L

R ZYX

WING STRUCTURES (FREEBODY DIAGRAM)

FBZ

FBY

FEZ

B E

100”

180”

4 lb/inREAR SPAR

Using Geometric relation

lb 648

90*180*4*100

0

EZ

EZ

B

F

F

M

lb 1080

lb 32460

648

10030

EY

EX

EYEX

F

F

FF

lb 72

648180*4

0

BZ

BZ

Z

F

F

F

FEX

FEY

WING STRUCTURES (TRUSS)

G

EB

30” 30” 40” 40” 40”A

L

KI

JP

O

N

MFGY=4320

FBY

FAY

17515075 200200

FEY=1080

FEX=324 100

X

Y

00 PNY FF

1000 POX FF

JOINT O

167

10013.53

0

ON

ON

X

F

CosF

FJOINT P

JOINT E

JOINT N

JOINT M300

0 2001.53

0

NM

ONNM

X

F

CosFF

F

133

13.53Sin

0

NE

ONNE

Y

F

FF

F

500

13.53

0

ME

MENM

X

F

CosFF

F

lbF

SinFF

F

OM

ONOM

Y

133

13.53

0

lbF

FSinFF

F

MG

OMMNMG

Y

533

13.53

0

824

52413.53

0

GE

MEGE

X

F

CosFF

F

lbF

FSinFF

F

MG

NEMEEL

Y

547

108013.53

0

WING STRUCTURES (TRUSS)

lbF

SinFF

F

LJ

GJLJ

Y

547-

551

13.53

0

G

EB

30” 30” 40” 40” 40”A

L

KI

JP

O

N

MFGY=4320

FBY

FAY

17515075 200200

FEY=1080

FEX=324 100

X

Y

lb 1373

13.53

0

GL

GEGL

X

F

FCosF

F

lbF

SinFF

F

GK

GLGK

Y

533

5951

432013.53

0

JOINT G

lb 998

017513.53

0

LK

LKGL

X

F

FCosF

F

JOINT L

JOINT K

lb 1412

045

0

KJ

LKKJ

X

F

FCosF

F

lbF

SinFF

F

KI

KJKI

Y

05950

6948

45

0

WING STRUCTURES (TRUSS)

G

EB

30” 30” 40” 40” 40”A

L

KI

JP

O

N

MFGY=4320

FBY17515075 200200

FEY=1080

FEX=324 100

X

Y

JOINT J

JOINT I

lb 1148

015045

0

IJ

IJKJ

X

F

FCosF

F

lbF

SinFF

F

JB

KJJB

Y

551

1550

45

0

lb 1624

45

0

IB

IJIB

X

F

FCosF

F

lbF

SinFF

F

IA

KJIA

Y

8096

6

94845

0 lbFF

F

IAAy

Y

8096

0

JOINT A

JOINT B

lb 2698

45

0

BY

JBIBBY

X

F

FCosFF

F

FAY

FAX

lbF

F

BA

Y

1225-

0

lbF

F

AX

Y

1225

0