Figure 9-61.—Filling the bucket.JOB LAYOUTMany excavation jobs are small and routine. Otherjobs may be quite extensive. On small jobs, you willnormally be shown where to dig and to what depth youmust dig. On larger jobs, you maybe shown the plan ofthe proposed ditches. Grade stakes on the projects aremarked to indicate to what depth the ditches must beexcavated. (Chapter 15 covers grade stakes in detail.)NOTE: Before starting any excavation, you mustensure a valid digging permit is present that covers thearea you are tasked to excavate.When arriving at the project site, you may noticetwo rows of grade stakes: one row on the center line ofthe proposed ditch and the other row offset a givendistance from the center line. Do not disturb the offsetstakes. They are the stakes you will follow whileexcavating the ditch that have information relative to thedepth of the excavation written on the side.9-27Figure 9-62.—Measuring the depth of a ditch.As a guideline, you can use a string drawn taut fromthe first centerline stake to the following centerlinestakes for a distance of several hundred feet ahead of themachine. Then spray paint over the string with abright-colored paint that will mark the ground to beexcavated. With the bucket centered over the firstcenterline stake, you will be able to excavate the paintedline. If you get off center, you can bring the backhoeback into alignment gradually by steering the machinein the desired direction.Check your grade (ditch depth) frequently. You cando this by using a straight board, a carpenter’s level, anda measuring stick or tape measure. Align the cornerbottom of the horizontal board on the crowfoot cut,marking of the offset stake. Place the level on thehorizontal board and adjust the board opposite the stakeuntil the level indicates the board is level. Measure fromthe bottom edge of the board to the bottom of the ditch,as shown in figure 9-62. This measurement shouldcorrespond to the amount of cut indicated on the stake.All of the stakes will be cut stakes. You should alwaystry to excavate to the depth specified on the stakes.NOTE: It is better to excavate an inch or two belowgrade than not excavate deep enough.FOUNDATION EXCAVATIONThe backhoe is used to make excavations forbasements or any other square- or rectangular-shapedjob. It is also used extensively for digging wide trenchesfor laying water and sewer pipe. When the backhoe isused for the digging of square- or rectangular-shapedjobs, the procedures may vary with the shape of the job,restrictions caused by surrounding buildings, or special
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business