The Physics Of Trusses

• The English Box Frame

These results were as expected, that is, that force Ay points down from external forces, Ax points towards the center. However, the snow frictional force has much more effect on the truss than what was expected.
I did have to play with the frictional force a bit. It was stated that the friction coefficient was 1.0, however, a web page said that slate has a frictional coefficient of .76. This means that there would always be a net acceleration on the snow while on the 45 degree slope. However, due to do unforeseen reasons I know from experience living in Maine that slate roofs at a 45 degree slope hold snow.