2E4: SOLIDS & STRUCTURES

Lecture 1

Dr. Bidisha GhoshNotes: http://www.tcd.ie/civileng/Staff/Bidisha.Ghosh/Solids & Structures

What does the module cover?

The module covers two fundamental concepts:

•Strength of Materials(covered by Bidisha Ghosh)

•Theory of Structures(covered by Alan O’Connor)

Recommended Text

It is a must that you OWN a book on the subject, Mechanics of Materials/ Strength of Materials/Mechanics of Solids

Buy it first or second hand or download it

•Mechanics of Materials by A. C. Ugural (Wiley)Structures—or why things don’t fall down by JE Gordon (Penguin)•Strength of Materials by S. Timonshenko

Assessment

•Written Exam (85%)

•Two Laboratory Experiments (5% each)oBeam BendingoColumn Buckling

•10 tutorials (5 BG and 5 AOC)Attendance is worth 50% of tutorial marks. Students must attend the tutorial sessions during weeks 2 to 6, inclusive, and weeks 8 to 12:Groups A and B: 9:00am to 10:00am in the Drawing Office, Museum Building.Groups C and D: 10:00am to 11:00am in the Drawing Office, Museum Building.

Beam Bending

•Load will be applied on a simply-supported beam

Beam Bending

•The beam will bend with compression at top and tension at bottom.•Deflection will be calculated using dial gauges.•The strain will be measured using strain gauges.•Stress will be calculated from the strain measurements.

Sensors

Strain and deflection gauges will be used.

Buckling of a Strut

Buckling is a large deformation produced under compressive load in a direction or plane normal to the direction of application of the load.

End conditions

Four different end conditions show four different shapes of buckling.

StepsLoad bars with different end conditions in the loading frames and observe the different shapes and critical load:1) Effect of end condition:•Draw the first mode shape for the four different end conditions in the small loading frame.•Measure the effective length for each end condition.

1I) Effect of length•Measure the critical load for two bars having different length in the big loading frame.•Measure the width and depth of the section of the bars•Calculate the radius of gyration of the section of the bars.

Different End-Conditions