Supports TUTORIAL 3 er just click on the button or image related to the
Supports
TUTORIAL 3
to answer just click on the button or image related to the answer
Question 1 how many reactions can be producedby a fixed support? What are they?
2 – horizontal, verticala
3 – horizontal, vertical, moment b
more c
Question 2
1 - verticala
how many reactions can be producedby a simple support? What are they?
2 – horizontal, vertical b
3 – horizontal, vertical & moment c
Question 3
1 - verticala
how many reactions can be producedby a roller support? (pinned at top)
2 – vertical,
horizontal b
3 – vertical, horizontal,
moment
c
Question 4
1 - verticala
how many reactions can be producedby a pinned (hinged) support? What are they?
2 – vertical, horizontal b
3 – vertical, horizontal,
moment c
Question 5
1 - verticala
2 – vertical, horizontal b
3 – vertical, horizontal, moment c
how many reactions can be producedby the structural system shown? What are they
Question 6 What does structurally determinate mean ?
structure has 3 reactions a
can use just the 3 equations of staticequilibrium to calculate reactions
c
a and b d
b reactions cannot be calculated usingthe 3 equations of static equilibrium alone
a and c e
how many reactions can be producedby the structural system shown? Draw them
Question 7a
1a
2 b
3 c
4 d
simple support
Question 7b is the system?
statically determinatea
statically indeterminate b
a mechanism c
simple support
how many reactions can be producedby the structural system shown? Draw them
Question 8a
1a
2 b
3 c
4 d
pin joints
Question 8b is the system?
statically determinatea
a mechanism c
pin joints
statically indeterminate b
how many reactions can be producedby the structural system shown? Draw them
Question 9a
2 a
4 b
6 c
simply supported
Question 9b
is the system?
statically determinatea
statically indeterminate b
a mechanism c
simply supported
how many reactions can be producedby the structural system shown? Draw them
Question 10a
2 a
3 b
4 c
6 d
Question 10b
is the system?
statically determinatea
statically indeterminate b
a mechanism c
how many reactions can be producedby the structural system shown? Draw them
Question 11a
1a
2 b
3 c
more d
Question 11b is the system?
statically determinatea
statically indeterminate b
a mechanism c
next question
enough !
H
V
M
a fixed support can have 3 reactionshorizontal H, Vertical V and moment M
let me try again
let me out of here
try harder
we are talking about a fixed support
let me try again
let me out of here
we are talking about just one support
next question
enough !
a simple support can only have 1 reaction - just a vertical, V. If you apply a force horizontally - it moves
V
let me try again
let me out of here
we are talking about a simple support
(think what happens if you apply a force horizontally)
let me try again
let me out of here
we are talking about a simple support
(think what happens if you apply a force horizontally.Think what happens to the ends. Do they go up –i.e. they rotate?
If they do then there is no moment reaction)
next question
enough !
a roller support can only have 1 reaction - just a vertical, V. If you apply a force horizontally - it moves
and since it is pinned it can’t produce a moment reaction
V
let me try again
let me out of here
we are talking about a roller support
(think what happens if you apply a force horizontally what happens if you push someone on roller skates – do they resist?)
let me try again
let me out of here
we are talking about a roller support
(think what happens if you apply a force horizontally what happens if you push someone on roller skates – do they resist?
Since it is pinned what happens if you apply a force to a hinge – does it rotate or resist? Think of opening a door)
next question
enough !
a hinged support can only have 2 reactions - a vertical, V. and a horizontal, H
It can’t produce a moment reaction
V
H
let me try again
let me out of here
we are talking about a hinged support
(think what happens if you apply a force horizontally can it come off the hinge? What happens if you pull a door?)
let me try again
let me out of here
we are talking about a pinned support
(think what happens if you apply a force horizontally can it come off the hinge? What happens if you pull a door?
Since it is pinned what happens if you apply a force to a hinge – does it rotate or resist? Think of opening a door)
next question
enough !
this is a rigid supportRemember Question 1?
VH
V
M
let me try again
let me out of here
we are talking about a fixed support
(remember Question 1?) Does it pull out of the wall? Does it spin/rotate?
That’s it exactly. A statically determinate structure is one that can produce exactly 3 reactions.
Statically determinate means just that:You can use the 3 equations of static equilibrium to calculate the reactions
next question
enough !
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that’s part of the story
what would happen if there were 2 reactions, or 4?think of the word ‘determinate’ – what does that mean?
let me try again
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statically determinate
what would happen if there were 2 reactions, or 4?think of the word ‘determinate’ – what does that mean?
that’s it exactly!
next question
enough !
3 reactions for the rigid support (V, H, M) and 1 for the simple support (V) makes 4 altogether
simple support
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let me out of here
THINK !!
how many reactions can a cantilever produce?how many reactions can a simple support produce?
that’s it exactly!
next question
enough !
more than 3 reactions makes a system statically indeterminate,meaning that the reactions cannot be determined
by the 3 equations of static equilibrium
simple support
let me try again
let me out of here
THINK !!
how many equations of static equilibrium are here?therefore what make a system statically determinate?
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let me out of here
THINK !!
what makes a mechanism?(when ‘structure’ cannot provide the necessary reactions)
how many reactions have we got?
that’s it exactly!
next question
enough !
2 reactions (V, H) for each pin jointed support makes 4 altogether
pin joints
let me try again
let me out of here
THINK !!
how many reactions can one pin joint produce? how many pin joints are there?
that’s it exactly!
next question
enough !
more than 3 reactions makes a system statically indeterminate.that means the reactions cannot be determined
by the 3 equations of static equilibrium
pin joints
let me try again
let me out of here
THINK !!
how many equations of static equilibrium are here?therefore what make a system statically determinate?
let me try again
let me out of here
THINK !!
what makes a mechanism?(when ‘structure’ cannot provide the necessary reactions)
how many reactions have we got?
that’s it exactly!
next question
enough !
1 reaction (V) for each simple support makes 2 altogether
simply supported
let me try again
let me out of here
THINK !!
If you push from the side what happens? Does it resist?Is there anything to prevent the ends from rotating?
So how many reactions can one simple support produce?how many simple supports are there?
that’s it exactly!
next question
enough !
less than 3 reactions makes a system a mechanism.If you push from the side, the beam will move (slide). This is a mechanism
simply supported
let me try again
let me out of here
THINK !!
How many reactions do you need to make a system statically determinate?How many reactions do you need to make a system statically indeterminate?
that’s it exactly!
next question
enough !
3 reactions for each rigid joint (V, H, M) makes 6 altogether
let me try again
let me out of here
THINK !!
how many reactions can a rigid support produce?how many rigid supports are there?
that’s it exactly!
next question
enough !
more than 3 reactions makes a system statically indeterminate,meaning that the reactions cannot be determined by just
using the 3 equations of static equilibrium
let me try again
let me out of here
THINK !!
What makes a system a mechanism?How many reactions do you need to make a system statically determinate?
How many reactions do you need to make a system statically indeterminate?
that’s it exactly!
next question
enough !
2 reactions for the pin joint (V, H) and 1 for the roller (V) makes 3 altogether
let me try again
let me out of here
THINK !!
how many reactions can a pin joint produce?how many reactions can a roller support produce?
So how many reactions are there in total?
that’s it exactly!
the END
3 reactions makes a system statically determinate,meaning that the reactions can be determined by just
using the 3 equations of static equilibrium
let me try again
let me out of here
THINK !!
What makes a system a mechanism?How many reactions do you need to make a system statically determinate?
How many reactions do you need to make a system statically indeterminate?