Structural Engineering Challenge

Our project is to make a bridge for Dub G Construction. This bridge is set to begin construction this summer in Pittsburgh PA. Our team is trying to make a bridge that will hold the greatest weight while also maximizing the use of materials before failing.

Criteria 

Constraints 

1. The bridge will be built with a 2x4 abutment on either side

1. The bridge must span a predetermined distance between two areas

2. The maximum length of the span is thirty inches, minimum is twenty inches

2) All joints must be glued

3. Max depth is 6” and Min is 4”

3) We may not touch the bridge during testing

4. Max height is 6” and Min is 3”

4) The bridge must hold the weight in the bridge center

5) The bridge must allow for a string to be hung around it.

6) The bridge must be the structure which holds the weight, not the testing devices or the floor.

Design Elements & Features

1. Bridge must be able to hold weight.

2. It should be able to be steady while holding weight.

3. It should hold as much weight as possible.

Resource

Purpose

We researched how the forces would be applied on many different kinds of bridges.

We researched this to understand how these different kinds of trusses would withstand weights.

We researched the Pratt Truss design.

We researched the Pratt Truss to find its strengths and weaknesses. We found this truss design is easy to construct, cost effective, and good for spanning long distances. However, it buckles very easily, is very tall, and is not good for horizontal loads.

We researched the Warren Truss design.

When researching the Warren Truss design we found its strengths are that it is very strong, it is very simple, and it is good for long spans. However, we found its weaknesses are that it is not as good at concentrated loads and it is bad for long distances.

We researched the King Post truss design.

During the research of the King Post Truss we found that its strengths are that it is cost effective, very versatile, and is very strong. Its weaknesses are that it is too flexible and complex.

We researched the Fan truss design.

We researched the Fan truss design and found its strengths are that it is efficient, cost effective, and can hold a lot of distributed weight. It’s weaknesses are that it’s hard to build, ineffective at one point of pressure.

We researched the K truss

We found that the K truss design’s strengths are that it is cost effective, strong, and versatile. Its weaknesses are that it is flexible, bad for long spans of weight, and complex.

Top View

Side View

Balsa wood (⅛ x ⅛)

Balsa wood (¼ x ⅛)

Balsa wood (⅜ x ⅛)

Wood Glue

https://bridge-building.pages.dev/https://ei.jhu.edu/truss-simulator/

Task / Step

Person Responsible

Deadline Date

1

Bridge choosing

Everyone

9/29

2

2d drawing

Ella

10/4

3

Material choosing

      Everyone

10/3

4

Sketch up

Logan

10/7-10/8

5

Construction

Landon and Braden

10/11

6

Website

Simon

10/11

No.

Problem

Solution

1

We made an error on our 2d design

We were able to fix the error before it caused any problems

2

We were having issues with our 3d design

We were able to fix our 3d design with assistance from Mr Geary

3

We were running out of time for our building

We are able to get more time by going in during our lunch period

Test

Resolution

1

We used a website to test how the forces will be applied to our bridge.

We now know how the forces apply to our bridge. This will allow us to improve our design.

2

We are going to complete a test by applying weight to our bridge model.

We will now know what breaks in our design, so we can strengthen these parts.

Our project was to make a bridge for Dub G Construction. This bridge is set to begin construction this summer in Pittsburgh PA. Our team has been trying to make a bridge that will hold the greatest weight while also maximizing the use of materials before failing. We did meet the criteria by building our bridge to be strong while still not being too heavy.