The main grand challenge that we faced this semester was population growth and urban congestion. After this, we want to focus on our solution, which was a floating bridge. Our design depended on the beam bridge idea, which is a large pontoon. After choosing the design, we used the sketch to make our prototype.
The project crossed with; the first step, we used a Minecraft machine to cut the sticks to the correct length, which we needed using a special technic. Then, we made the span and two-layer stick with each other by using glue. After that, we make the bottom of the bridge. In this part, we made it from two layers approximately, when we started to make the sides (height) of our design. We focused on the angle between the sides and bottom of the bridge. Before we made the bridge, we started to stick the parts of the bridge with glue and wax, then; we started to use the isolating material to isolate the wood and the glue from the water.
The loads in the beam bridge are distributed as follows: the loads go down on the deck, then move to the sub girders under the bridge, after that, move to the primary girder, then to the supports, and finally to the ground.
We apply Archimedes’ law in our design to make our bridge equilibrium, and it says (different pressure equals the density of water * gravity* volume of water) pressure represented by the weight of the load divided by the area of the surface of the bottom.
We put in our mind the law of the center of mass of the bridge when we test it. We must take attention to calculating the center of mass to put the weight on it, and to calculate the center of mass of any object; we use this formula (m1.x1 * m2.x2*…../total mass) that is in an X-axis, in a Y-axis we change the x into a y.
We used newton’s third law(F1=-F2) in estimating the loads over the bridge such that the loads over the bridge represent F1 and the resistance of the deck of the bridge represents F2 because every action reacts equally in magnitude and opposite in direction.
We wanted to make our design have the ability to become more stable. So, we make the area of the bottom bigger than the area of the deck according to the law of pressure that is equal (total force divided by area). If we increase the area, we will decrease the pressure. So, the bridge will become more stable. We use the isolated material more than once because it will make the bridge very good at isolating from water.