Yup....and I've never heard anyone suggest to load in the middle. Lots easier to sight load on the ends and will cause less stress to the trailer over time.

Axle Group Limitations
The maximum allowable weight for all individual axles and axle groups is limited by statute:

Group Type - Maximum Allowable Weight Single Axles - 20,000 pounds Tandem Axles - 34,000 pounds Tridem Axles - 42,000 pounds Other Axle Groups - based on the Bridge Weight Formula.