Deflection lab report
FACULTY OF ENGINBERING AND BUILT ENVIRONMENT
BEng (Hons) Civil Engineering
Structure I
Deflection
Contents:
Introduction 3
Objectives 3
Apparatus 4
Procedure 4
Results 4
Discussion 7
Conclusion 7
References 8
Introduction:
The deflections of a beam are an engineering concern as they can create an unstable structure if they are large. People don’t want to work in a building in which the floor beams deflect an excessive amount, even though it may be in no danger of failing. Consequently, limits are often placed upon the allowable deflections of a beam, as well as upon the stresses. When loads are applied to a beam their originally straight axes become curved. Displacements from the initial axes are called bending or flexural deflections. The amount of flexural deflection in a beam is related to the beams area moment of inertia (I), the single applied concentrated load (P), length of the beam (L), the modulus of elasticity (E), and the position of the applied load on the beam. The amount of deflection due to a single concentrated load P, is given by:
Objective:
Is to find the relationship between the deflection at the center of a simply supported beam and the span, width.
Apparatus:
Frame with Movable Knife Edge Supports.
Steel rectangular beam.
Weights. (0.5N)
Ruler.
Dial Gauge.
Vernier calliper.
Procedure:
I. We’ve arranged the beam span as 1000mm by locating the knife edges on the beam supports, then the mid span point has been measured, thus we were able to place the load hanger.
II. We’ve measured the width and depth of the beam.
III. We’ve settled gauge by assuming the load hanger as zero load.
IV. We’ve applied first 0.5N on the load hanger and recorded the first reading of the deflection by the dial gauge instrument.
V. By adding 0.5N to the load hanger we were able to record the next readings.
VI. Then we’ve taken
BEng (Hons) Civil Engineering
Structure I
Deflection
Contents:
Introduction 3
Objectives 3
Apparatus 4
Procedure 4
Results 4
Discussion 7
Conclusion 7
References 8
Introduction:
The deflections of a beam are an engineering concern as they can create an unstable structure if they are large. People don’t want to work in a building in which the floor beams deflect an excessive amount, even though it may be in no danger of failing. Consequently, limits are often placed upon the allowable deflections of a beam, as well as upon the stresses. When loads are applied to a beam their originally straight axes become curved. Displacements from the initial axes are called bending or flexural deflections. The amount of flexural deflection in a beam is related to the beams area moment of inertia (I), the single applied concentrated load (P), length of the beam (L), the modulus of elasticity (E), and the position of the applied load on the beam. The amount of deflection due to a single concentrated load P, is given by:
Objective:
Is to find the relationship between the deflection at the center of a simply supported beam and the span, width.
Apparatus:
Frame with Movable Knife Edge Supports.
Steel rectangular beam.
Weights. (0.5N)
Ruler.
Dial Gauge.
Vernier calliper.
Procedure:
I. We’ve arranged the beam span as 1000mm by locating the knife edges on the beam supports, then the mid span point has been measured, thus we were able to place the load hanger.
II. We’ve measured the width and depth of the beam.
III. We’ve settled gauge by assuming the load hanger as zero load.
IV. We’ve applied first 0.5N on the load hanger and recorded the first reading of the deflection by the dial gauge instrument.
V. By adding 0.5N to the load hanger we were able to record the next readings.
VI. Then we’ve taken
References: Mechanics of Materials, Russell C. Hibbeler Experimental methods: an introduction to the analysis and presentation of data, By Les Kirkup Mechanics of Materials (8th ed.), By Gere, James M., Goodno, Barry J. Materials Science and Engineering an Introduction (4th ed.), William D Callister, JR (Frank Durka and Hassan al Nageim, 2003)