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This thought leads to the advisability of providing house capacity capable of handling the ultimate freight business as determined by the physical life of the facilities. On general premises such a step appears illogical and careful study would seem to indicate the wisdom of providing facilities sufficient to serve present requirements plus a reasonable increase. Preconceived provisions in the general design of house and tracks should be of such character that an increase in facilities may be had at any time without destroying their unity.

Factors of Design.

After the relation between the various classes of freight has been determined and the volume of business for present and ultimate development has been decided upon, the problem resolves itself into a determination of individual factors of design, and it is these factors which will be discussed in the succeeding paragraphs.

Inasmuch as this study contemplates a discussion of these factors for one level L.C.L. freight houses only, no consideration will be given those which have a relation to multiple level houses. It is to be hoped that subsequent reports of the Association will consider the latter factors very fully and present data on that phase of the problem.

The factors which will be considered here are enumerated below:

Width of roadway.

Width of occupancy per vehicle against tailboard.

Speed of vehicles along roadway.

Average loading per vehicle in tons.

Average loading per car in tons.

Average time of loading or unloading per vehicle.

Rate of turnover of freight received at Inbound House

and relation to floor space required.

Floor area required per ton of Inbound freight.

Floor area required per ton of Outbound freight.

Floor area required for storage of Outbound freight.

Peak vehicle loads-Inbound and Outbound House.

Average tonnage which can be handled per day per lineal

foot of tailboard and per door.

Tailboard required per car.

Number and spacing of scales.

Spacing of doors.

Economic length of house.

Floor live load, per square foot.

Width of Roadway.

The question of roadway width is dependent primarily on size of vehicles to be accommodated and whether the roadway will serve buildings on one or both sides. In order to obtain information on the size of vehicles commonly used for freight purposes, observations were made recently at the South Water Street facilities of the Illinois Central Railroad at Chicago. This information is shown in Table No. 1.

TABLE 1-SIZE OF VEHICLES

Data Obtained From Observations Made at the I. C. R. R. South Water Street Freight Terminal, Chicago, Sept. 14-15, 1921.

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NOTE: Extreme width, unless otherwise noted, gives width of wagon bed in feet.
H-Indicates width over hub caps in feet.

*Indicates over all length to head of horse in feet.

From this data it may be observed that the average length of all vehicles measured was 22.48 ft. with a maximum of 27 ft., and that the average width of all vehicles measured was 6.53 ft. with a maximum of 7.6 ft.

It may be further observed that the average length and width of horse drawn vehicles is considerably greater than that of motor trucks. Inasmuch as horse drawn vehicles still function to a large degree in the hauling of freight and will probably continue to do so for many years to come, it seems proper that the space provided per vehicle should be somewhat larger than the average vehicle dimensions noted above, and it is suggested that an arbitrary length and width of 25 ft. and 8 ft., respectively, be used in computing the width of roadway required. In the discussion which follows all vehicles will be assumed to occupy a position at right angles to the tailboard. A saw tooth tailboard arrangement wherein the vehicle backs against tailboard at an angle other than 90 degrees has been used at a number of recent freight houses, but will not be included in this discussion owing to lack of data pertaining to definite operating advantages found at these houses as a result of its use.

If the roadway is to serve a house on one side only, it is apparent that after allowing two lanes of travel, each 8 ft. wide and a vehicle space length of 25 ft., that a width of 41 ft. will be required.

If houses on both sides of the roadway are to be served there should be provided wherever possible two lanes of travel each 8 ft. wide and a vehicle space length of 25 ft. each for two vehicles placed in juxtaposition, thus giving a roadway 66 ft. wide. While this width cannot always be obtained, a roadway not less than 60 ft. appears to be the minimum which should be provided if local conditions will permit. If the roadway is obstructed by columns a reasonable increase in width should be made. In support of the above data it is interesting to note that in an investigation of a number of existing freight houses it was found that widths of 27 ft. to 50 ft. have been used for roadways serving houses on one side only. Where houses are served on both sides of the roadway the same investigation shows that widths from 58 ft. to 74 ft. have been used. Width of Occupancy Per Vehicle Against Tailboard.

Table No. 2 gives the result of observations made recently to determine this factor. From this data it may be observed that the average width of occupancy was 8.82 ft. and that 72 per cent of the vehicle groups observed averaged between 8 ft. and 10 ft. In an article describing the recent New York Central freight terminal in Cleveland (Engineering News, Vol. 82, pages 508 to 510), it is stated that a door spacing 10 ft. center to center, each door serving one vehicle, was used. Based on the above data and information it would appear that a width of 10 ft. to 12 ft. should be sufficient for this factor.

TABLE 2-WIDTH OF OCCUPANCY PER VEHICLE

Data Obtained From Observations Made at I. C. R. R. South Water Street Freight Terminal, Chicago, September 14-15, 1921

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This information, shown in Table No. 3, is necessary in order to determine the loss of time incident to the travel of a vehicle along the roadway while en route to the tailboard. It is of interest to note that the speed of horse drawn vehicles is almost exactly one-half that of motor trucks. Owing to the increasing preponderance of motor trucks in use for hauling freight, it is felt that a speed somewhat higher than the average of 7.04 M.P.H. might well be adopted and a speed of 8 M.P.H. is suggested. It should be observed that this factor need be considered only in the case of long houses.

TABLE 3-SPEED OF VEHICLES

Data Obtained From Observations Made at the I. C. R. R. South Water Street Freight Terminal, September 15, 1921

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Average speed for motor trucks........10.32 miles per hour
Average speed for 3-horse wagon.. 3.95 miles per hour
Average speed for 2-horse wagons.. 4.50 miles per hour
Average speed for 1-horse wagons.. 6.22 miles per hour

Average speed for all vehicles...... 7.04 miles per hour

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