The first step to any experiment that tests the strength of wood is to choose the exact type of wood you wish to test. You may wish to test wood that is specifically used for building materials, or perhaps you prefer to comparatively test wood that is salvaged from old buildings versus newly cut wood. Another option would be to choose wood that has been pressure-treated and fire retardant to compare their strength against untreated wood.
One experiment you may choose would be to determine if treated and untreated wood retain the same level of strength. This experiment is great for a science class, but it is also handy for anyone needing to test building materials they wish to use. A simple technique used for testing the strength of wood is to use a device created specifically for a three-point bend test. These apparatuses are used to test the flexibility and bend of different materials, such as wood or metal. Choose a variety of untreated and treated wood, or treat the wood as you would need for your specific project. Cut the wood to the exact dimensions and use the testing device to see at what point the wood bends or breaks.
Perhaps you wish to discover which type of wood is the strongest, since this information could be valuable for a construction project. There are so many materials you can choose from, so decide on the type of wood you want to use for your project. You can also choose a random variety of wood based on availability or price. Once you have the types of wood chosen, you will want to ensure that the variables are all constant within the experiment. Length of wood, temperature, humidity and weights for testing all need to be the same for each test. Balance the wood between two structures that are a set distance apart and use the same weight to place in the middle of the piece of wood that is set on the two structures. Increase the weights until the wood flexes or breaks and track the results of each type of wood.
There are dozens of different varieties of hardwood and softwood to choose from. A hardwood tree does not necessarily mean that it is harder than softwood. Hardwood comes from deciduous trees, and softwood comes from conifer trees. Design an experiment to test for exactly what type of wood you need to use. If you are making a piece of furniture, you can test the strength of hardwoods, such as maple, oak or cherry. To decide on the strength of different softwoods, consider testing the different strengths of pine or cedar.