(AI+Al=AZ=1.85 =D =Az)x 1.85 x Distance= Cubic yardsArea of one end cross sectionArea of other end of cross sectionConstant factorDistance between two end areas thatmust be changed to a decimal form; for example,250 feet = 2.50, 125 feet = 1,25, 75 feet = .75, and soforthTo compute the equation take the area of one endsection (cross section) plus the area of the other end andmultiply the sum of the two areas by a constant factorof 1.85. This value should now be multiplied by thedistance between the two end areas to determine thenumber of cubic yards. (See fig. 4-12.)Earthwork equations to compute the volume ofconcrete are outlined in chapter 7. Other areas, such asequations to compute for prime and tack costs, single-and double-surface treatments, and asphalt volumes, areoutlined in chapter 8.EQUIPMENT ESTIMATESEquipment estimates are used with productionschedules to determine the construction equipmentrequirements and constraints for a construction project.One fact that must be remembered is that the speed ofthe equipment usually averages between 40 to56 percent of the posted speed limit. The primary factorsresponsible for the variation in the percentage of theposted speed limit are as follows: road conditions, thenumber of intersections, the amount of traffic, andhauling distances. Other factors considered are the typesof material hauled (for example, damp sand or loam ismuch easier to handle than clay), safety (equipmentlimitations), operator experience, conditions of theequipment, work hours, and the local climate.Equipment production must be determined so theamount and type of equipment may be selected.Equipment production rates are available in the SeabeePlanner’s and Estimator’s Handbook, NAVFAC P-405.The handbook provides information on estimatingconstruction work elements and material quantities,including equipment and manpower requirements. Theproduction rate per day should be estimated for eachpiece of equipment. Consider the factors discussedabove, information obtained from NAVFAC P-405, andyour experience. The quantity of work divided by theproduction rate per day produces the number of daysrequired to perform the project. Equipment required tosupport each construction activity is documented on theConstruction Activity Summary Sheet (CAS sheet) (fig.4-13), which is part of the project package. One of thepurposes of the project package is to allow the projectsupervisor and the assigned P&E crew to perform adocumented thorough analysis of their assigned projectand to lay out an organized sequence plan of operationin order to complete the assigned tasking. Detailedinformation on project packages, project planning,project execution, and construction project supervisionare outlined in the Naval Mobile Construction BattalionCrew Leader’s Handbook.4-11