Concrete Railroad Ties. The problem of the future supply of ties is one of the most serious that confronts the railroads. It should be re membered, too, that the widespread building of interurban trolley lines throughout the country has also tended to drain the visible sources of supply.
The life of an ordinary hewn tie is not more than two years. Sawed ties do not last as long as that. This means that every tie in every rail road system of the country has to be renewed every two years. The forestry bureau of the United States Government has information that there are not enough trees in the country now to supply the demand. So serious is the situation that the Pennsylvania Company, in 1902, com menced planting locust trees along its lines, set ting out 480,000 of them, and it is the intention to set out 800,000 more.
But there is a solution to the problem. Ce ment has been found by actual tests to make the best possible tie. It makes a tie, too, that will not wear out and never have to be renewed. Experiments on a number of roads have proven the actual serviceability of cement for this pur pose. In an interview some time ago, the chief engineer of one of the large trunk lines said: "There have been many fitful attempts to make a sat isfactory concrete tie. The idea that concrete will not stand the shock of impact under heavy and high-speed trains is erroneous; for blocks of concrete, even without steel, when properly ,designed and arranged, are capable of supporting the heaviest traffic. The French roads in Indo-China have been using concrete for some years and to a large extent.
"The design here described (the 'Percival,' Plate 30) was completed and first put in track in November, 1901. It consists of two blocks of concrete, each three feet long, placed symmetrically under each rail so that the center of pressure and the center of figure of each section will coincide.
"These two blocks of concrete make one tie and are rigidly connected by being moulded on the ends of a pair of three-inch channels weighing three pounds per foot. The channels are back to back, and spaced two inches apart in the clear. The concrete blocks are seven inches thick and nine inches face; and the cross-section is the same as that of a timber tie hewn or slabbed from a log about eleven inches in diameter. It presents the appear
ance in the track of an ordinary tie with a piece 2 feet 11 inches long cut out of the center. Hardwood blocks three inches thick, nine inches wide, and eighteen inches long, designed to cushion shocks, distribute pressure, support derailed trucks, and serve as spiking blocks, are secured to the top of the concrete blocks. Each hard wood block is, of course, centered transversely to the line of the rail.
"Cast-iron sockets that also serve to space and con nect the channels are moulded in place in the concrete, and serve as an anchorage for holding down the hard wood blocks. These sockets receive suitable bolts, head down, so that when they are slipped to place and the holes through which they are introduced have been plugged they cannot be withdrawn. The first ties put in have been in service over four years and small lots have been put in from time to time since. The last were put in the track of the Chicago & Alton Railway in October, 1905. Of all the ties put in from the first to the last, none has failed. Three and one-half years ago 1,700 of these tics were put in the track of the Pere Marquette Railroad in Bay City, Mich. The ties were put down on a concrete bed; and each tie was set to the grade, being embedded in a joint of cement mortar. The rails were then spiked down and the track filled in." But outside of all matters of a shortage of supply of wooden ties, there is a still more important aspect to the question of using cement ties as against wooden ones. The loss of life that has resulted from the drawing of spikes and the spreading of rails on curves, it would be hard to estimate and awful to contemplate. The heavy equipment of the railroads of to-day is a contributing cause of the increased number of accidents. Locomo tives have been built of a size and weight utterly unwar ranted by the development of the tracks and roadbeds. The spreading of rails laid on wooden ties, which causes so many frightful accidents, can be traced in almost every instance, either directly or indirectly, to the spikes which are drawn out of the ties or by the cutting down of the rail into the ties.