First of all, what exactly is a Crate Bridge? A crate bridge is a bridge made up only of crates, simple right? In reality, this is a little more difficult. In a construction, different forces are acting, think of gravity and different compression and tensile forces. To keep the bridge standing, all these forces must be in equilibrium, which requires a well thought out design.
To start off, the shape and length of the arch were considered. This is very important because they have a major impact on the distribution of forces. To break the world record, the bridge has to be at least 27 meters long. To exceed this, the span of our bridge has been set at 36 meters with a small margin for contraction. For the shape of the bridge a catenary arch has been chosen. This type of arch is used more often in bridges and is therefore the perfect fit for our crate bridge. On both sides of the arch there will be two high towers that will ensure that the bridge does not collapse. Knowing the dimensions of the bridge, the forces that will play a role in the construction can be calculated. Through this method, it can be determined how much force is needed for every layer to withhold the bridge from collapsing. This force is called the compression force. This is the force that must be applied to the ends of the bridge to cause enough pressure to make sure the bridge does not tumble.
The most important point in the bridge is in the middle. This is where the most forces are at play and where things could go wrong first. The compressive force that must be provided by the towers must outweigh the force at play in the middle of the bridge, but must not be too great that it will deform and break the crates too much. All the different steps were put into a model and in this way all the variables could be calculated. This led to the beautiful design of the crate bridge which can be seen below.