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Introduction 1 Lecture 1 Architectural Structures I ENDS 231 Su2006abn ARCHITECTURAL STRUCTURES I: STATICS AND STRENGTH OF MATERIALS ENDS 231 DR. ANNE NICHOLS SUMMER 2006 one statics and strength of materials lecture

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Page 1: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 1Lecture 1

Architectural Structures IENDS 231

Su2006abn

ARCHITECTURAL STRUCTURES I:STATICS AND STRENGTH OF MATERIALS ENDS 231

DR. ANNE NICHOLS

SUMMER 2006

one

statics and strength of materials

lecture

Page 2: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 2Lecture 1

Architectural Structures IENDS 231

F2005abn

Syllabus

Page 3: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 3Lecture 1

Architectural Structures IENDS 231

F2005abn

Course Description• statics

– physics of forces and reactions on bodies and systems

– equilibrium (bodies at rest)• structures

– something made up of interdependent parts in a definite pattern of organization

Page 4: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 4Lecture 1

Architectural Structures IENDS 231

F2005abn

Course Description• mechanics of materials

– external loads and effect on deformable bodies

– use it to answer question if structure meets requirements of

• stability and equilibrium• strength and stiffness

– other principle building requirements• economy, functionality and aesthetics

Page 5: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 5Lecture 1

Architectural Structures IENDS 231

F2005abn

Structure Requirements• stability &

equilibrium– STATICS

Page 6: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 6Lecture 1

Architectural Structures IENDS 231

F2005abn

Structure Requirements (cont)• strength &

stiffness– concerned with

stability of components

Page 7: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 7Lecture 1

Architectural Structures IENDS 231

F2005abn

Structural System Selection• kind & size of loads• building function• soil & topology of site• systems integration• fire rating• construction ($$, schedule)• architectural form

Page 8: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 8Lecture 1

Architectural Structures IENDS 231

F2005abn

Knowledge Required• external forces• internal forces• material properties• member cross

sections• ability of a material to resist breaking• structural elements that resist excessive

– deflection– deformation

Page 9: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 9Lecture 1

Architectural Structures IENDS 231

F2005abn

Problem Solving1. STATICS:

equilibrium of external forces, internal forces, stresses

2. GEOMETRY:cross section properties, deformations and

conditions of geometric fit, strains3. MATERIAL PROPERTIES:

stress-strain relationship for each material obtained from testing

Page 10: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 10Lecture 1

Architectural Structures IENDS 231

F2005abn

Relation to Architecture“The geometry and arrangement of the

load-bearing members, the use of materials, and the crafting of joints all represent opportunities for buildings to express themselves. The best buildings are not designed by architects who after resolving the formal and spatial issues, simply ask the structural engineer to make sure it doesn’t fall down.” -Onouye & Kane

Statics and Strength of Materials for Architecture and Building Construction

Page 11: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 11Lecture 1

Architectural Structures IENDS 231

F2005abn

Architectural Structures• incorporates

– stability and equilibrium– strength and stiffness– economy, functionality and aesthetics

• uses– sculpture– furniture– buildings

Page 12: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 12Lecture 1

Architectural Structures IENDS 231

F2005abn

• evolution traced to developments in structural engineering and material technology

– stone & masonry– timber– concrete– cast iron, steel– tensile fabrics, pneumatic structures......

Architectural Space and Form

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Introduction 13Lecture 1

Architectural Structures IENDS 231

F2005abn

The “Fist”Detroit, MI

Page 14: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 14Lecture 1

Architectural Structures IENDS 231

F2005abn

AISC (Steel) Sculpture

College Station, TX

Page 15: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 15Lecture 1

Architectural Structures IENDS 231

F2005abn

“Jamborie”Philadelphia, PADaniel Barret

Page 16: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 16Lecture 1

Architectural Structures IENDS 231

F2005abn

Exploris MobileHeath Satow

Page 17: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 17Lecture 1

Architectural Structures IENDS 231

F2005abn

“Telamones”Chicago, ILWalter Arnold

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Introduction 18Lecture 1

Architectural Structures IENDS 231

F2005abn

“Free Ride Home” 1974Kenneth Snelson

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Introduction 19Lecture 1

Architectural Structures IENDS 231

F2005abn

“Zauber”Laudenslager, Jeffery

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Introduction 20Lecture 1

Architectural Structures IENDS 231

F2005abn

Conference Table

Heath Satow

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Introduction 21Lecture 1

Architectural Structures IENDS 231

F2005abn

Bar Stool“Stainless Butterfly”Daniel Barret

Page 22: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 22Lecture 1

Architectural Structures IENDS 231

F2005abn

ChairPaul Freundt

Page 23: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 23Lecture 1

Architectural Structures IENDS 231

F2005abn

End TablesRameu-Richard

Page 24: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 24Lecture 1

Architectural Structures IENDS 231

F2005abn

Steel House, Lubbock, TXRobert Bruno

Page 25: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 25Lecture 1

Architectural Structures IENDS 231

F2005abn

Guggenheim Museum BilbaoFrank Gehry (1997)

Page 26: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 26Lecture 1

Architectural Structures IENDS 231

F2005abn

Tjibaou Cultural Center, New Caledonia

Renzo Piano

Photographer: John Gollings

Page 27: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 27Lecture 1

Architectural Structures IENDS 231

F2005abn

Padre Pio Pilgrimage Church, ItalyRenzo Piano

Photographer: Michel Denancé

Page 28: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 28Lecture 1

Architectural Structures IENDS 231

F2005abn

Athens Olympic Stadium and Velodrome

Santiago Calatrava (2004)

Page 29: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 29Lecture 1

Architectural Structures IENDS 231

F2005abn

Milwaukee Art Museum Quadracci Pavilion (2001)

Santiago Calatrava

Page 30: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 30Lecture 1

Architectural Structures IENDS 231

F2005abn

Airport Station, Lyon, FranceSantiago Calatrava (1994)

Page 31: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 31Lecture 1

Architectural Structures IENDS 231

F2005abn

Centre Georges Pompidou, ParisPiano and Rogers (1978)

Page 32: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 32Lecture 1

Architectural Structures IENDS 231

F2005abn

Hongkong Bank Building (1986)

Foster and Partners

Page 33: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 33Lecture 1

Architectural Structures IENDS 231

F2005abn

Meyerson Symphony Center Dallas, TX Pei Cobb Freed & Partners

Page 34: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 34Lecture 1

Architectural Structures IENDS 231

F2005abn

Crystal Cathedral, LAPhilip Johnson (1980)

Page 35: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 35Lecture 1

Architectural Structures IENDS 231

F2005abn

Federal Reserve Bank Minneapolis, MN Gunnar Birkerts & Associates

Page 36: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 36Lecture 1

Architectural Structures IENDS 231

F2005abn

Hysolar Research BuildingStuttgart, Germany (1986 -87) Gunter Behnisch

Page 37: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 37Lecture 1

Architectural Structures IENDS 231

F2005abn

Notre Dame CathedralParis, France Maurice de Sully

Page 38: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 38Lecture 1

Architectural Structures IENDS 231

F2005abn

Habitat 67, MontrealMoshe Safdie (1967)

Page 39: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 39Lecture 1

Architectural Structures IENDS 231

F2005abn

Villa Savoye, Poissy, FranceLe Corbusier (1929)

Page 40: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 40Lecture 1

Architectural Structures IENDS 231

F2005abn

Riola Parish ChurchRiola, Italy Alvar Aalto (1978)

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Introduction 41Lecture 1

Architectural Structures IENDS 231

F2005abn

Kimball Museum, Fort WorthKahn (1972)

Page 42: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 42Lecture 1

Architectural Structures IENDS 231

F2005abn

Structural Math• quantify environmental loads

– how big is it?• evaluate geometry and angles

– where is it?– what is the scale?– what is the size in a particular direction?

• quantify what happens in the structure– how big are the internal forces?– how big should the beam be?

Page 43: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 43Lecture 1

Architectural Structures IENDS 231

F2005abn

Structural Math• physics takes observable phenomena

and relates the measurement with rules: mathematical relationships

• need– reference frame– measure of length, mass, time, direction,

velocity, acceleration, work, heat, electricity, light

– calculations & geometry

Page 44: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 44Lecture 1

Architectural Structures IENDS 231

F2005abn

Physics for Structures• measures

– US customary & SI

litergallonVolume

TemperatureForceMass

LengthUnits

CFN, kNlb forceg, kglb mass

mm, cm, min, ft, miSIUS

Page 45: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 45Lecture 1

Architectural Structures IENDS 231

F2005abn

Physics for Structures• scalars – any quantity• vectors - quantities with direction

– like displacements– summation results in

the “straight line path”from start to end

– normal vector is perpendicular to something

y

xz

Page 46: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 46Lecture 1

Architectural Structures IENDS 231

F2005abn

Language • symbols for operations: +,-, /, x• symbols for relationships: (), =, <, >• algorithms

– cancellation– factors– signs– ratios and proportions– power of a number– conversions, ex. 1X = 10 Y – operations on both sides of equality

31

322

62

65

52

=×//

==/

×/

31

6=

x

1000103 =

1101

110

=YXor

XY

Page 47: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 47Lecture 1

Architectural Structures IENDS 231

F2005abn

On-line Practice • Webct / Study Tools

Page 48: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 48Lecture 1

Architectural Structures IENDS 231

F2005abn

Geometry• angles

– right = 90º– acute < 90º– obtuse > 90º– π = 180º

• triangles– area– hypotenuse– total of angles = 180º

2hb×

=

222 BCACAB =+

A

B

C

Page 49: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 49Lecture 1

Architectural Structures IENDS 231

F2005abn

Geometry• lines and relation to angles

– parallel lines can’t intersect

– perpendicular lines cross at 90º– intersection of two lines is a point

– opposite angles are equal when two lines cross α

βαβ

Page 50: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 50Lecture 1

Architectural Structures IENDS 231

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Geometry– intersection of a line with

parallel lines results in identical angles

– two lines intersect in the same way, the angles are identical

αβαβ

αβαβ

α α

α

Page 51: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 51Lecture 1

Architectural Structures IENDS 231

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Geometry– sides of two angles are parallel and

intersect opposite way, the angles are supplementary - the sum is 180°

– two angles that sum to 90° are said to be complimentary

α β

βγ

α

°=+ 90γβ

Page 52: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 52Lecture 1

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– sides of two angles bisect a right angle (90°), the angles are complimentary

– right angle bisects a straight line, remaining angles are complimentary

Geometry

αγ

γ

°=+ 90γα

α

Page 53: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 53Lecture 1

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– similar triangles have proportional sidesGeometry

BC

E

A

A

BC

A′

C′

B′

DEBC

AEAC

ADAB

==

CBBC

CAAC

BAAB

′′=′′

=′′

D

α

α

ββγ

γ

Page 54: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 54Lecture 1

Architectural Structures IENDS 231

F2005abn

Trigonometry• for right triangles

B

ACBAB

hypotenusesideopposite

=== αsinsin

CBAC

hypotenusesideadjacent

=== αcoscos

ACAB

sideadjacentsideopposite

=== αtantan

SOHCAHTOA

Page 55: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 55Lecture 1

Architectural Structures IENDS 231

F2005abn

Trigonometry• cartesian coordinate system

– origin at 0,0– coordinates

in (x,y) pairs– x & y have

signs

-6-5-4-3-2-10123456

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6X

Y

Quadrant IQuadrant II

Quadrant III Quadrant IV

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Introduction 56Lecture 1

Architectural Structures IENDS 231

F2005abn

Trigonometry• for angles starting at positive x

– sin is y side– cos is x side

-6-5-4-3-2-10123456

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6X

Y

sin<0 for 180-360°cos<0 for 90-270°tan<0 for 90-180°tan<0 for 270-360°

Page 57: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 57Lecture 1

Architectural Structures IENDS 231

F2005abn

Trigonometry• for all triangles

– sides A, B & C are oppositeangles α, β & γ

– LAW of SINES

– LAW of COSINES

CBAγβα sinsinsin

==

αcos2222 BCCBA −+=

A

α CBγ

β

Page 58: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 58Lecture 1

Architectural Structures IENDS 231

F2005abn

Algebra• equations (something = something)• constants

– real numbers or shown with a, b, c...• unknown terms, variables

– names like R, F, x, y• linear equations

– unknown terms have no exponents• simultaneous equations

– variable set satisfies all equations

Page 59: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 59Lecture 1

Architectural Structures IENDS 231

F2005abn

Algebra• solving one equation

– only works with one variable– ex:

• add to both sides

• divide both sides

• get x by itself on a side

012 =−x10112 +=+−x

21=x21

22

=// x

12 =x

Page 60: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 60Lecture 1

Architectural Structures IENDS 231

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Algebra• solving one equations

– only works with one variable– ex:

• subtract from both sides

• subtract from both sides

• divide both sides

• get x by itself on a side

5412 +=− xx

xxxx 254212 −+=−−

55251 −+=−− x

22

223

26

//

=//⋅−

=− x

3−=x

Page 61: one lecture - Texas A&M Universityfaculty-legacy.arch.tamu.edu/anichols/index_files/courses/ends231/ends... · Lecture 1 Architectural Structures I ENDS 231 ... load-bearing members,

Introduction 61Lecture 1

Architectural Structures IENDS 231

F2005abn

Algebra• solving two equation

– only works with two variables– ex:

• look for term similarity• can we add or subtract to eliminate one term?

• add

• get x by itself on a side

832 =+ yx6312 =− yx

6831232 +=−++ yxyx1414 =x

11414

1414

=== xx