Q2 Z2,(Q2) Z2(Q2) - Institute for Water Resources - U.S. Army

deceleration, Equation (3.8). Moreover, some analysis of the num-
ber of stops en route would be required in order to include the
effects of acceleration and deceleration on a train's output.
Cargo Capacity and Light Weight of Rail Train
Recall that the linehaul process function is the product of
two terms: (1) the cargo tonnage of the vehicle and (2) the aver-
age speed of the vehicle between origin and destination. The second
of these terms will be developed in the next and following sections -
of this chapter for the case of rail. The cargo tonnage of a train
will be discussed in this section beginning first with a discussion
of the cargo tonnage of a rail car and then generalizing this dis-
cussion to the cargo tonnage of a rail train. The remarks made here
concerning the cargo tonnage of rail trains are applicable to all
different types of rail cars and to trains composed of a variety of
types of cars. Note that this was not the case in the tow process
function. In the analysis of tow cargo capacity, a particular barge
type was selected and used exclusively in the analysis, although
methods were suggested for generalizing this procedure. The use of
one type of barge was necessitated by the fact that the tow resis-
tance formulation had been estimated for only one barge type. In
the case of rail, on the other hand, the resistance function is not
based solely on one rail car type, nor is_it dependent on a partic-
ular configuration of rail cars, i.e., the order of the rail cars
comprising a train does not affect the total resistance.
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