CHAPTER III

ENGINEERING

The subjects generally discussed in this chapter are matters coming under the direction of the chief engineer, who is in all cases a civil engineer. This division embraces not only civil engineering work, but also that usually coming under direct supervision of an electrical engineer, who reports to the chief engineer. There is a sharp distinction, however, between the term engineering as here used and mechanical engineering, which relates to the design, construction, and maintenance of motive power and rolling stock, and which is discussed later.

The work of the engineering department may be divided into two distinct parts, construction and maintenance of way. On a road having one or more sections of its line electrified there are separate divisions for electrical construction and maintenance in the electrical zone.

CONSTRUCTION

The chief engineer is responsible for the construction of the railroad. The location of its line involves a great deal of detailed field examination and office study and analysis on his part. Prior to the beginning of construction, standard plans for roadbed sections, track, bridges, culverts, buildings, and the numerous structures of a railroad are prepared, as well as plans for structures and situations requiring special treatment.

Plats showing accurately the dimensions and areas of all land required for right-of-way, station, or terminal purposes are made, so that all such land may be definitely described in deeds transferring it to the company.

Specifications for the construction of the railroad are prepared describing in detail the character of the various classes of work to be done and prescribing the manner of doing it. Proposals to do the work are invited from contractors and when received are tabulated and compared and the contract is awarded on the basis of the proposal which is the most advantageous. The contractor then assembles his forces and plant and actual construction begins.

The right of way and real estate are acquired as far in advance of actual construction as conditions will allow. It is rarely all obtained before construction begins, and its acquirement is often a source of serious delay to the construction forces. The work is generally performed by men trained through former service in that particular field. In cases of lines constructed in a country without transportation facilities, securing the necessary land is a comparatively easy matter; in a district already provided with railroad facilities, it is often a tedious, expensive, and vexatious feature of the construction, involving much negotiation and at times condemnation proceedings. The right-of-way men generally report to the chief engineer, but often to the general counsel.

The work is divided for construction purposes into sections varying in length as to the character of the construction. On light work—that is, where the country is comparatively flat with no important bridges or other structures and construction-a section may be from ten to fifteen miles long as a maximum; on heavy work, involving the moving of large quantities of material,

the sections are reduced to six or eight miles, and with much bridge or special work they are still shorter.

These sections are called "residencies" and are in direct charge of a resident engineer, who with his party directs the construction in accordance with the plans, specifications, and instructions of the chief engineer. The party consists generally of three men in addition to the resident engineer and such inspectors of masonry, pile, and timber structures as the nature of the work may require.

The resident engineer sets stakes marking the outside lines of all cuts and fills and in doing so cross-sections the surface of the ground to determine the quantities of material to be moved; he defines the lines of all masonry, timber, and other structures and sets stakes to mark the limits of the company's right of way and real estate.

During the construction of the work the character of material excavated is carefully noted for the purposes of classifying it, as the unit price paid for the material depends on whether it is earth, loose rock, or solid rock. Foundations for all structures are carefully examined before building; all material, such as sand, stone, cement, piles, timber, pipe, etc., is inspected before being used.

As the contractors are paid monthly, the resident engineer makes an estimate of the amount of work done at the end of each month, which is sent to the office of the chief engineer as the basis of the payment.

On almost any line of railroad there are one or more important bridges which are under the direct supervision of the bridge engineer, who usually reports directly to the chief engineer.

In a rough or mountainous district involving the construction of long tunnels, such work is generally in

charge of a resident engineer familiar with underground construction.

The office engineer supervises the drafting of all maps and plans, checks the monthly and final estimates, and indexes and files all estimates, reports, and notes as they are completed in the field.

As the roadbed is finished ready for the track, the superintendent of track begins the actual laying of the rails, which is usually done with the railroad company's own forces. Prior to the track laying, the rails, ties, joints, spikes, switches, etc., have been received and stored in a material yard, convenient to the point of beginning of the track laying. Where steel bridges are to be erected, the masonry is constructed at the same time as the rest of the work, but the steel superstructure is not erected until the track has been laid to the bridge site. The material for bridge superstructure is stored in the same yard as the track material and is moved to the bridge site by the construction trains of the track force.

All this track, bridge, and other building material is received at the material yard and checked out to the track forces by the material clerks, who account for all of it to the superintendent of track, who in turn reports to the chief engineer.

As track laying progresses, the construction of stations, telegraph lines, water tanks, and other necessary buildings and structures and retaining fences begins, following the track construction as closely as possible, the material for such structures being hauled by construction trains from the material yard to the sites of the structures. As the track is surfaced-that is, brought to true line and proper grade for actual operation-the road crossings, cattle guards, and such structures are placed, so that by the time track laying and

surfacing are completed the line is ready for actual operation and is turned over to the operating department.

RECONSTRUCTION

The reconstruction of a railroad is often undertaken primarily for the purpose of reducing the controlling grades and improving the alignment (eliminating curves), but there are some other very important matters given consideration at the time of such reconstruction.

The original roads of the country were from economical necessity constructed as cheaply as possible. Where the business of a road continually increases there comes a time when more money can be saved in operating expense by making certain improvements than the interest on the cost of such improvements. Under such circumstances if the money market is normal and the credit of the company good, such improvements are undertaken, and the chief engineer through his construction organization determines the most feasible and economical plan for reconstructing those portions of the line where the conditions surrounding the operations demand it.

On all railroads there are grades called maximum or controlling grades, which limit the tonnage that any given locomotive can haul over a division. These grades usually occur where the railroad crosses ridges or mountains in passing from one system of drainage into another. By reducing the grade-that is, the rate of rise (as from 1 foot in 100 feet to 0.5 feet in 100 feet), the tonnage of the train may be increased. Such grade reduction generally increases the depth of the excavations near and at the summit of the grade, and the height of the embankments in the valley, as well as the length of the "fill."