Introduction: The Victory Bridge (Suspension Pedestrian Bridge Made in Revit)
Hello, my name is Minul Gamage and I am a rising junior at Staten Island Technical High School. Throughout my sophomore year I learned how to use Revit, and when I heard about the Make It Bridge Contest I decided to put those abilities to the test by building a bridge that connects West Shore Staten Island to New Jersey.
Location
The location of this bridge will be on the Western Shore of Staten Island, NY to New Jersey. The only bridges that allow pedestrians that connect New Jersey and Staten Island are all located on the North Shore of Staten Island. This makes it difficult for South Shore and others on Staten Island to walk to New Jersey as they would have to travel all the way to the North Shore.
The Goal of the Bridge
The main goal of this bridge is to connect the communities of New Jersey and other parts of Staten Island in a way that doesn't require a person to have a car or use one. This would encourage more people to walk or bike to New Jersey which would not only promote fitness but would also be more environmentally friendly as there would be fewer cars going to New Jersey and vice versa. Also, this would make commutes and travel much easier for people living near the bridge as a 10-mile commute would be cut to a tiny fraction of that.
Explanation of the Name of the Bridge
The main tower of the bridge looks similar to a V and the bridge would be connected to Staten Island through the street "Victory Blvd." I decided not to pass off this naming opportunity and call this bridge the Victory Bridge.
Supplies
Revit, Enscape, Google Maps
Step 1: Brainstorming and Topography
The first step I had to do was to decide where I was going to build this bridge. The area I plotted on the map was the shortest distance across the body of water that I could find that didn't cross into an existing building or port. I wanted the connection to make sense so I decided this space would be satisfactory. Next I had to brainstorm all the locational problems this bridge would be facing. One problem was the fact that there was a cargo port nearby so my bridge would have to be tall enough to allow cargo ships to pass through. Another problem was connecting this bridge to existing roads. I have decided to extend an existing road in Staten Island to one end of a bridge and the other end would connect to another existing road in New Jersey. Next, I created a rough sketch of the topography in the picture using Revit.
Step 2:
In order to create the towers I spent quite some time brainstorming on a few designs. I ended up liking the design as seen with the hand-drawn picture above and tried to replicate it in Revit using massing. First I started with the concrete rectangular foundation on the bottom. Then I created a substructure for the towers, which are the 80-foot metal columns beneath the foundation that go under the ground. This provides the tower with the necessary support it needs. After that I created a rough sketch of the tower and I ended up with a V-shaped tower. The towers span a height of about 320 feet and at the top, they have a width of about 120 feet. The towers also have 60 feet of space in between them. While this may seem large for a pedestrian bridge, I am planning on including a dedicated separate bike path which would take up half the space. Additionally, I would later change the format of the cables later on but so far the design was going to plan.
Step 3: Deck Structure
After creating the towers I went to plan the deck. This deck would be 130 feet tall which should be enough to allow ships to pass through into the port. It would also be about 2,300 ft long. While this may be a large length for a pedestrian bridge, it still shortens the average travel time if a person was to walk from South Shore Staten Island to Jersey. I created a design that has a straight deck in the middle that stretches for 288 feet then on both sides, there is an arc of 14.51 degrees that goes to the ground. Each of the arcs is 1000 feet in length horizontally. I tried to create a similar structure pattern to the Golden Gate Bridge as I was inspired by the deck design of it. After that, I created steel beams (both on the top and the bottom of the structure) that connected both sides of the deck as seen in the Enscape screenshot. After that, I now had to create the walkable deck which would be shown in a later step.
Step 4: Creating the Anchor Towers
This step was quite simple as the anchor towers are just smaller versions of the main towers. I used the mirror tool to create the anchor towers from the main towers and adjusted the design of the anchor towers and decided to go with the design as seen in the screenshot.
Step 5: Finishing the Deck and Adding Thermal Expansion Joints
After creating the structure of the deck, I next had to create the other components of the deck. First I added a 4-inch layer of metal above the structure which would hold the concrete in place. Then I added a 1-foot layer of concrete which would be very sturdy in order for pedestrians to cross on it. Due to the freezing cold winters and roasting hot summers of this area, thermal expansion would very likely be an issue with this bridge. Thermal expansion would cause the concrete to expand during high-temperature conditions and contract when it cools down. This would definitely affect the bridge's survivability and in order to combat this, I used thermal expansion joints which were also designed using the massing tool. The thermal expansion joint design is seen in many other bridges and will allow the bridge to expand and contract without causing stress and cracking to the concrete.
Step 6: Cables
This is the step for one of the main and important parts of a suspension bridge, the cables. Creating the cables using massing proved to be quite tricky on Revit, but after trying to figure out some solutions I found out what best worked. I created a cable using massing in a different project (I got all the dimensions in order to create it from the original) and uploaded that new project into the original as a family. The main cables are 3 feet in diameter and on each side of the tower, they would be about 1000 feet long. After some adjusting, I got the main cables in place and attached them to the main towers and anchor towers. The main towers have a design that would allow the main cable to be supported by the towers. I made sure the main cables didn't have too much sag in order so it still hold tension. After finishing the main cables, I added suspenders in order to connect the deck to the cables. I also added suspender connectors from the deck in order to connect the deck and cables (as shown in one of the screenshots).
Step 7: Railings and Finishing Touches
Now that I was done with the fundamentals of this bridge, I now added some finishing touches to it. I added railings and this became a little tricky as Revit does not allow for railings to be built in a downward angle. In order to solve this I created my own custom railings for the deck arcs. I also added barriers at each end of the bridge in order to ensure no vehicles get on it. I have also since scrapped the idea of adding a dedicated bike path as I believe this would make the bridge look too much like a regular bridge for cars so now the whole deck would be open for both pedestrians and bikers.
Step 8: Conclusion
Thank you for taking the time to look over my bridge design and I hope you enjoyed learning about the process about how I designed this bridge.