The load acted on the lock wall should be simplified on the floor when the Ge’s table lookup method is utilized in the structure calculation of the lock’s dock. This paper makes calculations of different load simplified methods, and compares the results with the calculation results by the finite element method. It is indicated that the traditional simplified methods exist some problems in the view of structure mechanics and the reasonability of calculation results. Rational simplified methods of calculation load are recommended according to characteristics of different dock structures.