Bending Test On Wooden Beam

  • Uploaded by: Adil Javed Chaudhary
  • 0
  • 0
  • June 2020
  • PDF

This document was uploaded by user and they confirmed that they have the permission to share it. If you are author or own the copyright of this book, please report to us by using this DMCA report form. Report DMCA


Overview

Download & View Bending Test On Wooden Beam as PDF for free.

More details

  • Words: 769
  • Pages: 6
6. To Perform Bending Test on Wooden Beam (26-11-2008) Apparatus 10 ton Buckton UTM, Deflection Gauges, Wooden Beam, Measuring Tape

Objective •

To study the bending or flexural behavior of the beam



To determine the Modulus of Elasticity and Modulus of Rupture of the wood.

Related Theory Shear Force The sum of all the forces acting perpendicular to the section or forces which tend to slides two part of the section on each other.

Elastic Curve A line representing the deformed form of the center line of the beam is known as Elastic Curve.

Flexural Stress Stresses produced by the bending moment is known as Flexural Stress.

Stresses Internal resistance of the material against loading is known as Stress.

Flexural Equation It is the fundamental relationship between the Bending moment and geometry of deformation.

Flexural Formula It gives a relationship in bending moment and flexural stresses.

Modulus of Rupture • •

It is the energy absorbed per unit volume when the specimen is loaded from zero to failure. It is the maximum tensile stress which can be developed in the beam before failure. 1 Bending Test on wooden Beam Javed 07Civil73

Adil

Difference between Modulus of Rupture & Modulus of Toughness •

Modulus of Toughness can be determined by tension or compression test (axial tests) and it is for any type of member.



But Modulus of Rupture is only for a member having flexural or bending.

Loading Arrangement for Experiment Loading arrangement for this certain experiment is “Two point Arrangement”. This is to produce only bending, it will not cause any shear force in the beam.

Two point Arrangement Two equal loads acting at the equal distance from the supports is known as two point loading system. In such a system the shear force acting between the loads

2 Bending Test on wooden Beam Javed 07Civil73

Adil

is zero and bending moment between the loads is constant

3 Bending Test on wooden Beam Javed 07Civil73

Adil

Load is being applied on wooden bean in 10ton Buckton UTM

Wooden Beam after the Fracture

Procedure 1. First of all measure the breath and height of the wooden sample 2. 3. 4. 5.

through the measuring tape. Fix the wooden beam sample in 10 ton Buckton UTM. Fix the dial gauges under the beam as shown figure the figure above, according to the distances shown. Now apply the load gradually on the beam and note down the amount of deflection against each loading. Note down all the deflection up to failure of specimen and finally find the Modulus of Elasticity, Modulus of Rupture from their respective formulae.

Precautions 1. Apply the loads gradually so that we can read the deflection against

each reading easily. 2. Remove the gauges before the failure load, otherwise they may get damages. 4 Bending Test on wooden Beam Javed 07Civil73

Adil

3. Stay away from the machine or otherwise the particles may hurt

you.

Observations and Calculations Sr. No

Load (Tons)

Deflection Gauges Gx

1 2 3 4 5 6 7 8 9 10 11 12

0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 0.55

100 136 150 190 215 244 269 304 326 355 385 412

Gy 100 135 146 186 210 240 263 296 320 347 375 400

(Gx+Gy)/2 100 135.5 148 188 212.5 242 266 300 323 351 380 406

Gc 100 152 173 229 266 308 342 391 426 466 508 545

Net Deflection (mm) Δ=(Gc-Mean)X

L.C.X25.4 0 16.5 25 41 53.5 66 76 91 103 115 128 139

0 0.4191 0.635 1.0414 1.3589 1.6764 1.9304 2.3114 2.6162 2.921 3.2512 3.5306

Load (N) tonsX9810 0 490.5 981 1471.5 1962 2452.5 2943 3433.5 3924 4414.5 4905 5395.5

6000 y =1534.x- 76.62 5000

4000

) (N d a o L

3000

2000

1000

0 0 -1000

0.5

1

1.5

2

2.5

3

3.5

4

net deflectione (mm)

5 Bending Test on wooden Beam Javed 07Civil73

Adil

Calculations of Modulus of Rupture and Modulus of Elasticity b= 50 mm, h= 50mm,

l=1000mm

Breaking Load (Pmax):

1.15 tons = 11281.5 N

Modulus of Rupture =

=

Modulus of Elasticity = Slope of Straight line in graph i.e.

= 1534.4

Comments Wooden beam should be fracture symmetrically from the both sides because we have applied symmetrical load by Two Point Load System, but we can see from the sketch of wooden beam after fracture, it did not fracture in that manner. This can be due to some weakest plane in the way of fracture. On the right side of the beam it fractured perfectly.

6 Bending Test on wooden Beam Javed 07Civil73

Adil

Related Documents

Bending Rolls
December 2019 22
Bending Light
December 2019 15
Bending Radius.pdf
November 2019 16
Tube Bending
May 2020 11

More Documents from ""