EQUIPMENT

Knowing your equipment, its limitations, and its operating characteristics is part of the knowledge you need to know to be an efficient EO on earthmoving jobs.

Equipment production must be determined so that the correct amount and type of equipment is selected for a project. Equipment production rates are available in the Seabee Planner's and Estimator's Handbook, NAVFACP-405. The handbook provides information on estimating construction work elements and material quantities, including equipment and manpower requirements.

Before you begin earthmoving operations, it is often necessary to remove overgrowth, boulders, and other obstructions. Also, you often have to build a drainage system, so the construction site will drain. These operations are carried out with bulldozers, scrapers, graders, and similar equipment.

The load, hauled by a scraper, is usually referred to as either heaped or struck (fig. 15-63). When moving earth, take a full, heaped load and make it

Figure 15-63.-Heaped and struck load. 15-38

count. In earthmoving operations, travel can be time-consuming. Suppose you are operating a 12-cubic-yard scraper. It will carry about a 15-cubic-yard heaped load. If you carry only a struck (level) load of 12 cubic yards, you lose 3 cubic yards of load each trip. To move 60 cubic yards takes five trips when only 12 cubic yards are hauled each time. Hauling full, heaped loads, you would move the same amount of material in four trips. If your haul is short and units are waiting to go into the cut, you can increase production by taking only a good load (somewhere between struck and heaped) and moving out, rather than spending extra time obtaining a heaped load.

On most construction jobs, both cuts and fills are required. To increase job efficiency, plan your job so that the material taken from a cut is used in a fill area. This is known as balancing the material.

PIONEERING

Pioneering refers to the first working over of an area that is overgrown or rough and making that area accessible for the equipment needed for the project.

In pioneering, the operations of clearing, stripping, grading, and drainage are all done practically at the same time, rather than performed as separate operations. A dozer starts out along a predetermined route and leaves a road behind it. This may be a haul road on which trucks and equipment will use in later operations.

Suppose you, as a dozer operator, get the job of cutting a road on the side of a mountain to be used for access to a proposed airstrip or to reach a mountain stream to be developed into a water supply system. Where should you start and how should you proceed? The route your mountain road is to follow will be staked out by a survey party. You should start your road at the highest point possible and let the force of gravity help the dozer.

In clearing on sidehill cuts, brush and trees should be cast far enough to the side of the road so that they will not be covered with the earth. It is even better if you can cast them over the edge with an angle blade of the dozer when the road is cut. When cutting the road, do not watch the grade stake immediately ahead or you will find yourself below grade. Instead, watch the third or fourth stake down.

NOTE: It is better to be above grade and come back and cut down to grade than to be below grade and have to come back and fill.

CLEARING

Clearing is a construction operation consisting of cleaning a designated area of trees, timber, brush, other vegetation, and rubbish; removing surface boulders and other material embedded in the ground; and disposing of all material cleared.

Clearing, grubbing, and stripping are different in every climatic zone, because each has different types of forests and vegetation. The nature of a forest can be determined from records of the principal climatic factors, including precipitation, humidity, temperature, sunlight, and the direction of prevailing winds. The types of forests can be generally classified as temperate, rain, monsoon, or dry, according to the climates in which they exist.

Clearing usually consists of pushing uprooted trees, stumps, and brush in both directions from the center of the area to be cleared. Clearing should be accomplished so that debris (spoil material) is placed in a designated spot with only one handling. In clearing landing strips, for example, it is generally necessary to dispose of material along each side of the strip outside the construction site. If the site permits burning, the haul distance can be reduced by piling brush, stumps, and trees on the site and burning them. Production in this field must be estimated, rather than calculated.

GRUBBING

Grubbing consists of uprooting and removing roots and stumps. In grubbing, stumps that are difficult or impossible to pull out, even with winches, should be burned or blasted. Your supervisor will decide the method. If the stumps are to be removed by blasting, a qualified blaster must be called upon to do the job. If they are to be burned, you may be assigned the task. Green stumps require continuous application of heat before they catch fire. Check with your supervisor about safety measures that should keep the fire from getting out of control if you have to do any stump burning. Remember that it may take as long as 3 or 4 days for a stump to burn out. Keep a check on the burning during this period. If a project has a high priority and time must be saved, stumps will probably be blasted, rather than burned. When stumps havebeen removed, refill the holes and level the area to prevent the accumulation of water.