The direction factor 0.75 that has been used is just an example and is not related to any specific loading or analysis type. In most situations, you would use 1. The generated seismic load or base shear is multiplied by any factor that you put here. So…

First one comment. As part of the mass definition for the response spectrum load case 3, you should add the udl in the X direction as well as shown below. This is to ensure that vibration of masses in all possible directions are considered for the eigensolution…

Just adding a couple of points to what Kaushal already mentioned. For any static load case, you can take a look at the Statics Check Results Table as shown below to get summation of applied forces and also summation of moments about the origin. This…

You need to also consider the fact that you are using a R value and an I value which are factored in the equivalent static analysis but the response spectrum base shear does not account for these. If you include these factors ( by multiplying the direction…