EXPERIMENT 3

TITLE: FIXED END MOMENT FOR A FIXED END BEAM

OBJECTIVE: To determine the fixed end moment of a fixed end moment.

APPARATUS:

1. Two supports that can measure moment.2. A steel beam.3. A set of weights.

THEORY

The fixed end moment of a fixed end beam is given by:

M ABF =w∗a∗b ²

L² (1)

MBAF =w∗a ²∗b

L² (2)

PROCEDURE

1. The attachment is referred for the experimental set up2. The, two support is fixed tightly to the base with the equals distance between them on the span

of the beam.3. Next, the load cell is checked so that it is properly secured to the pivoting plate.4. The ends of beam are placed between the clamping plates of the supports and tightened

the two screws to fix the beam.5. Then the load hanger is clipped at the position where the beam is loaded.6. Later, the load is connected from support pier to the display unit, where each load cell occupied

one terminal on the display.7. Then, the display is switched on with channel 1 and the initial reading for each channel is

recorded.8. The reading of each load cell, is recorded when the load is hang on the hanger.9. Lastly, the pier reaction is recorded when the load is in increases on the load hanger.

RESULT

Beam Span =420mm

Distance of load from support A =300mm

Fixed end moment (exp) = (V*55)mm

TABLE 1

Load On The BeamN

Load Cell Reading At Support A, V A

NLoad Cell Reading At Support B, V B

N2 1.5 0.54 3.5 16 5 28 7 2.5

10 8.5 3

TABLE 2

Load On Beam , w

N

Fixed End Moment At Support ANmm

Fixed End Moment At Support BNmm

MF (exp) = V A * 55 MF (theory),refer equation 1

MF (exp)=V B * 55

MF (theory),refer equation 2

2 1.5*55 = 82.5 2∗120∗300²420²

= 122.4

0.5*55 = 27.5 2∗120²∗300420²

= 48.984 3.5*55 = 192.5 4∗120∗300²

420²= 244.89

1*55 = 55 4∗120²∗300420²

= 97.966 5*55 = 275 6∗120∗300²

420²= 367.35

2*55 = 110 6∗120²∗300420²

= 146.948 7*55 = 385 8∗120∗300²

420²= 489.80

2.5*55 = 137.5 8∗120²∗300420²

= 195.9210 8.5*55 = 467.5 10∗120∗300²

420²= 612.24

3*55 = 165 10∗120²∗300420²

= 244.90

Calculation each slope

Fixed End Moment At Support A Nmm Fixed End Moment At Support B Nmm

Theory slope = y2− y1x2−x1

Theory slope = 490−250

8−4

Theory slope = 60

Experiment slope = y2− y1x2−x1

Experiment slope = 370−190

8−4

Experiment slope = 45

Theory slope = y2− y1x2−x1

Theory slope = 190−95

8−4

Theory slope = 23.75

Experiment slope = y2− y1x2−x1

Experiment slope = 165−6510−4

Experiment slope = 16.67

Calculation Percentage error

Percentage error at support A Percentage error at support B

Percentage error = ¿¿ * 100

Percentage error = 60−45

60 * 100 = 25%

Percentage error = ¿¿ * 100

Percentage error = 23.75−16.6723.75 * 100 =

29.81%

APPENDIX

Fixed end beam apparatus and other apparatus. Use meter ruler to take distance between beams.

Sample of set of weight (load) Display unit of load cell .

L-key. This apparatus use for fixed any flexibility Data must be taken to record and calculated to fill the in beam skrew. table.

DISCUSSION

1. For a beam loaded with a single point as above, state the relationship between the fixed end moment and load.

When the load is added, the fixed end moment is increasing constantly.

2. Will the relationship between reaction and load be linear if the beam is loaded with more than 1 load with different magnitude? No, it is because different magnitude of load will cause the reaction increasing not in constant.

3. Comment on accuracy of result obtained in this experiment.The accuracy of result obtained is slightly different.

4. State the possible factors that might have influenced your result and means of overcoming it.

i. The screw at the fixed end support is not tighten properly. ii. The reading of the distance of load from support not taken accurately.

iii. The graph is not plotted properly. iv. The slope point is not taken accurately.

CONCLUSIONConclusion can be made from the experiment is when a beam is loaded with a single point, the fixed end moment value is increasing linearly to the load.