Structural Analysis Method: Moment Distribution

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When distributing moments at a joint, what is the first step?

Sum the moments at each joint

Unlock the joint

Distribute the moment among connecting spans

Determine the unbalanced moment at the joint (correct)

What is the resultant moment in the frame equal to?

Sum of moments calculated for the frame in Fig. 11–18b and Fig. 11–18c (correct)

The moment at joint B

Sum of forces acting on the frame

The force acting on the frame

In the context of moment distribution, what does 'Dist.CO' indicate?

A line where moments are locked

A line where moments are summed

A line where moments are distributed and carried over (correct)

A line where moments are distributed but not carried over

Why is only one cycle of moment distribution necessary in the given case?

Because the wall supports absorb all the moments Signup and view all the answers

What is the value of MCB in kilonewton-meters?

3.71 kN # m Signup and view all the answers

Why is the fixed-end moment in AB assumed to be the same as DC?

Because B and C are displaced equally and AB & DC have same properties Signup and view all the answers

What does a negative value for moment MBC indicate in this scenario?

The moment is acting counterclockwise on span BC Signup and view all the answers

What is the reason for assuming ΣFx = 0 in the analysis?

To simplify the calculations Signup and view all the answers

How are end shears calculated in this context?

From the equations of equilibrium applied to each span Signup and view all the answers

What does FEM stand for in the context of the text?

Fixed-End Moment Signup and view all the answers

What happens when a support at a joint is termed as a 'rocker'?

The support allows rotation but prevents translation Signup and view all the answers

Which method of analysis is being used in the provided text?

Displacement Method of Analysis Signup and view all the answers

What is the equation for the internal moment M in terms of the applied load u for the center span of a symmetric beam?

$M = 2EIu/L$ Signup and view all the answers

What is the stiffness factor for the center span of a symmetric beam with antisymmetric loading?

$K = 2EI/L$ Signup and view all the answers

In the context of symmetric beams with antisymmetric loading, what modification is made to the stiffness factor for the center span?

It is halved Signup and view all the answers

What does the internal moment at point B equal when analyzing a symmetric beam with antisymmetric loading?

The internal moment at point C Signup and view all the answers

What does the conjugate beam approach help simplify in the analysis of symmetric beams with antisymmetric loading?

Moment-distribution analysis Signup and view all the answers

How does antisymmetric loading affect the moment diagram of a symmetric beam?

It makes it asymmetric Signup and view all the answers

What is the main reason for proceeding the analysis on the basis of superposition?

Due to the unknown initial displacements Signup and view all the answers

What are the purposes of applying two restraining forces R1 and R2?

To determine fixed-end moments Signup and view all the answers

What occurs after the restraint at the ceiling of the first story is removed?

Fixed-end moments are caused in the frame Signup and view all the answers

What is the purpose of assigning specific numerical values to the fixed-end moments?

To distribute these moments in the frame Signup and view all the answers

What happens when the ceiling of the second story is given a displacement ∆″?

Fixed-end moments are distributed in the frame Signup and view all the answers

What process yields specific values of R″1 and R″2 after a displacement ∆″ is applied to the ceiling of the second story?

Moment distribution and equilibrium analysis Signup and view all the answers

What is the purpose of using moment distribution in structural analysis?

To satisfy compatibility of rotation at the joints and equilibrium requirements Signup and view all the answers

How are the fixed-end moments determined for each loaded span?

By referring to a table provided on the inside back cover Signup and view all the answers

What does DF = 1 represent in terms of distribution factors for joints on a beam?

Roller support Signup and view all the answers

In the moment-distribution process, what is done after determining the moments needed to put each joint in equilibrium?

Distribute the counterbalancing moments into the members at each joint Signup and view all the answers

What factor determines the distribution factor for each joint in moment distribution?

$\Sigma K$ Signup and view all the answers

How do positive fixed-end moments act on a beam span?

Clockwise Signup and view all the answers