Wk 5

Question 1

MDM table left column pattern? (Meanings)

Answer 1

DF (Distribution factor)
FEM (Fixed end Moment)
DUBM (Distribute UnBalanced Moment)
COM (Carry Over Moment)
DUBM
COM
…..

Question 2

DF equation
E.G. for this beam

Answer 2

DF only for points in the middle so for B

DF (BA), DF (BC)

DF (BA) = K (BA) / Sum K (B)

DF (BC) = K (BC) / Sum K (C)

Question 3

DF for Fixed end ? (A)
Pinned end? (D)

Answer 3

DF at A = 0

DF at D = 1

Question 4

Potential member stiffness in a MDM? (K)

When they occur?

Answer 4

4EI/L
= going towards a fixed end OR is in the middle

3EI/L
= has a free end (free to rotate)

Question 5

FEM (Free End Moment) of these loading conditions

Answer 5

For UDL, W = load per length*length

Question 6

DUBM eqn

Answer 6

Balanced moment * DF

Question 7

COF rules

Answer 7

=0.5
= going towards a fixed end OR is in the middle

= 0
= has a free end (free to rotate)

Question 8

what does the shear force diagram look like for this BMD?

Answer 8

diff reaction AND max BM from point load, SFD changes aixs

Question 9

Find the distance x to the max BMD of the UDL

Answer 9

Once get x, can make a cut in the beam ‘section’ before x value.

Equilibrium eqn then sub in value for x.

Question 10

Assumptions made in Moment Distribution Method (4)

Answer 10

No Axial Deformations

Supports are Ideal:
The supports (fixed, pinned, or roller) behave ideally, without slipping or deforming.

Linearity of Material Behavior:
The material of the structure is assumed to be linearly elastic, which means it follows Hooke’s Law (stress is proportional to strain).

Loads are Static:
The applied loads are considered static and do not vary with time.

Question 11

TUT 5 Q2

Answer 11

Question 12

20-21

Answer 12

Question 13

22-23

Answer 13