Lecture #1Student Objectives:

* You should know what the instructor expects from you to final grade

* You should be able to assess your level of knowledge for this course

* You should be able to recall the fundamentals of Strength of Materials

Lab Requirements• All groups are required to have

a name and team captain. (group size 5 to 6 people)

• Each group must hand in one write-up and email their data to the instructor.

• Groups should state the level of participation from each individual.

• Groups will always meet in classroom before going over to Lab.

REVIEW OF LECTURE#1LIST ALL OF THE COMMON CONSTRUCTION MATERIALS:

WOOD CONCRETEBITUMENSMASONRY

WHAT DETERMINES THE SELECTION OF THIS MATERIAL ??

COST

SUITABILITY

ENVIRONMENTAL IMPACT

ACCEPTANCE, Q/C, R & D

WHAT ASPECTS OF THESE PROPERTIES ARE IMPORTANT??

MECHANICAL PROPERTIES - SHEAR, TORSION,TENSION, ETC.

PHYSICAL PROPERTIES - DENSITY, SPECIFIC GRAVITY, ETC

CHEMICAL PROPERTIES - ITS COMPOSITION, ITS REACTION WITH OTHER ELEMENTS

HOW IS THE USE OF THIS MATERIAL GOVERNED??

MODEL CODES - BOCA, UBC, SBC,IBC 2000

ASTM & ACI (STANDARDS FOUND IN THE TEXT BOOK)

STRENGTH OF MATERIAL REVIEW(CHAPTER ONE CONT’D)

COMPRESSION TENSION

TORSION THIRD POINT LOADING

SPLIT TENSILE

STRAIN - STRAIN CURVESAND FORMULAS

WHAT ARE OTHER BEHAVIORS OF INTEREST ??

DEFORMATION DUE TO THERMAL EXPANSION

LtcL

SEE PAGES 7 & 8 IN THE TEXT FOR SAMPLE PROBLEM & TABLES

TXAP

AEPL

E

REMEMBER TO DO PROB.11 FOR HWK

ELASTIC LIMIT

PROPORTIONAL LIMIT

YIELD POINT

ULTIMATE STRENGTH

STRAIN

ST

RE

SS

STEEL VS CONCRETE

Elastic Modulus(slope)or Young’s Modulus (E)

f’c:5700 psi

f’c:4700 psi

f’c:4100 psi

f’c:3300 psi

f’c:2600 psi

strain(x10-4)

Str

ess

(psi

)Stress - Strain Diagram of various concretes

5.05.1 ')33( fcwE

ELASTIC FORMULAS

w= the unit weight of concrete

ACI 318 -modulus of Elasticity

for normal concrete the equation simplifies to:

5.0'57000 fcE

00005.02

12

SS

E

2bdPl

MOR

Modulus of Rupture

SM

F b

Flexural Stress Equation

max moment equation

SAMPLE DEFLECTION PROBLEM

A steel bar 4 sq. inches. in area is used to support a gravity load in building construction. If 1 foot of the bar is hanging vertically, and a load of 72000 lbs is being supported at the lower of the bar, determine the total elongation of the bar. (neglecting its own weight)

630 10E x psi

GENERAL DEFORMATION EQUATION

Modulus of Elasticity =

P/AE = Stress / Strain =

/L = P.L / A.E

1"

4 "

1' - 0'

Mild steel :

OVERVIEW OF CONCRETE TESTING

TEST THE AGGREGATES PROPERTIES

TEST THE CEMENT PROPERTIES

DESIGN THE MIX

BATCH THE MIX AND TEST IT

CRUSH CYLINDERS IN SEVEN DAYS

CRUSH CYLINDER IN 28 DAYS

PERFORM THE SPLIT TENSILE TEST

STRESS .VS. STRAIN

AIR DRY

SAMPLE WITH VOIDS, WATER, SOLIDS

VARIOUS DRYING CONDITIONS

OVEN DRY

CORRECT

LAB ERROR

SURFACE MOISTURE

=TOTAL MOISTURE -ABSORPTION

SATURATED SURFACE DRY

ODODSSD

ABS

%

OVEN DRIED WET SURFACE

(LAB TESTING ERROR)

SEVEN TEST FOR AGGREGATES

TEST#1 CA- Gs & ABSORPTION

WEIGH 8.8LB OF SAMPLE(AIR)

IMMERSE AGG IN WATER 24 HRS.

ROLL SAMPLE IN CLOTH (SSD)

SUBMERGE SAMPLE (SUB)

OVEN DRY THE SAMPLE (DRY)

CALCULATE -Gs (BULK), Gs (SSD),Gs(APPARENT), ABSORPTION

TEST#2 FA- Gs & ABSORPTION

WEIGH 500g OF SAMPLE(AIR)

IMMERSE AGG OR 6% M.C. (24 HRS)

BLOW DRY SAND (SSD)

SUBMERGE SAMPLE IN PYNC (SUB)

OVEN DRY THE SAND (DRY)

CALCULATE -Gs (BULK), Gs (SSD),Gs(APPARENT), ABSORPTION

TEST#3- DRY RODDED UNIT WEIGHT

WEIGH THE CONTAINER

ROD 1/3 WITH 25 STROKES

WEIGH THE CONTAINER & SAMPLE

CALCULATE THE BULK DENSITY

TEST#4 TOTAL & SURFACE MOISTURE

WEIGH FA & CA SAMPLE(AIR)

OVEN DRY SAMPLES (OD)

CALCULATE MOISTURES

TEST# 6 & 7 SIEVE ANALYSIS