Form and Function
This
project where form and function are taken into consideration in order to
structurally meet the guidelines for a bridge opening. The main objective for
this project is to design a pedestrian bridge with a 30’ x 40’ opening. The
opening will allow passing vessels to safely continue underneath the bridge.
Prototypes for bridges and also mechanisms will have
to be constructed in order for the opening to be possible. The form of each
bridge and mechanism is documented and tested. Ultimately the altered form of
the most successful bridge prototype will be combined to fit the function of
the mechanism.
Design Criteria
-Span:
190’
-Maximum
Height: 100’
-Width:
12’
-Opening:
30’ x 40’
-Structural
Members must be no longer than 20’
-Structural
members shall be 1’ x 1’
-No
slope greater than 1:12
-Pedestrian
bridge
-Physically
handicapped accessible
Bridge prototypes
Arc Bridge Cable
Stay Bridge Truss
Bridge
-These three bridges were chosen. The Form of each was
soon altered in order to fit the function of each mechanism.
Mechanisms & their Functions
-I chose three different
artifacts with complicated movements. The first artifacts in this diagram is an
umbrella. Each arm of the umbrella consists of joints that allow the mechanisms
to extract and contract. This was used as a lifting function. The second artifact
was a wire cutter. This mechanism was used to pull and compress as the knob
rotated. Also, i found a bottle opener. This was used
to either vertically or horizontally move an object as the arms moved in a
direct relationship with the center mechanism.
-Each one of these functions
was then carefully constructed into each bridge in order to systematically
create an opening for passing vessels.
3 x 3 Diagram
-This 3x3 diagram illustrates how the function of each
mechanism was carefully constructed into each bridge. The goal was to create a
system which interlocked the form and function of which allowed the opening to occur.
Preliminary Design
-For my preliminary design I
choose one of the three bridges from the 3x3 diagram. I then had to further
alter the bridge in order to properly construct the mechanism and its function
into the bridge. I choose to use the Cable stay bridge and the function of the
umbrella arm in order to create the opening needed for passing vessels.
Transformation Process
-During
the transformation process of the cable stay bridge it grew clear that I had to
alter the form of the bridge. If I wanted the function of the umbrella arm to
cooperate with the bridge, I had to make some adjustments. I started off with
adding a cantilever assembly in order to support the umbrella arm. I proceeded
with making sure the cantilever was properly supported by the cables of the
original structure. Knowing the umbrella arm was supported, I then added a
system of truss supports beside the cantilever for extra support. Large turbine
like supports were added on top. Each supported the umbrella arm cables; as
they were in motion. In The middle of each one was a rotating mechanism that
assisted the umbrella arm as it contracted. A track had to be added in order to
keep the opening from moving horizontally as it was lifted.
Mechanism
When designing the mechanism,
I had to carefully look how each, and every axis extended and contracted. I
then decided that I can take just one arm and use that as a lifting mechanism.
Each part of the arm turned on its own axis as it lifted the opening. In order
to let each section of the arm move properly I had to make the middle section
smaller and leave the outer two sections equal.
Extended-Bridge closed
Contracted-Bridge open
Animated: Mechanism in action
Final Design
Bridge Closed
Bridge Open
Animation: Bridge in action
