bituminous  pavement  on  a  150-foot  by  600-foot  parking lot. The unit weight (which usually ranges from 140 to 160 pcf) should be determined from laboratory testing when possible; however, when the unit weight is not known, an estimated weight of 160 pcf maybe used. In this example, let’s assume a unit weight of 147 pcf. From this, we can estimate the tons of plant mix required by substitution into the above formula as follows: 600  x  150  x  2  x  147 = 1,102.5 tons. 12  x  2000 Then if we include a loss factor of, let’s say 5 percent, we will need 1,158 tons of plant mix for this parking lot. Now, let’s assume that this same parking lot is to be laid over a compacted-soil subbase. In this case, we will need a prime coat also. The prime coat is a low-viscosity liquid bitumen that is sprayed on the subbase. It provides a  seal  and  promotes  adhesion  between  the  subbase  and the  pavement.  To  estimate  the  amount  of  bitumen required for the prime coat, multiply the area to be treated by the rate of application The estimate should include enough bitumen for an additional width of 1 foot on each side of the pavement. A formula for estimating the number of gallons of primer needed is as follows: Where: L = W = AR = Gallons  = L  x  W  x  A R 9 Length of paved area in feet Width of paved area in feet Application rate of bitumens in gallons per square yard So, if the project specs for the parking lot we have been discussing call for an application rate of 0.3 gallons of  prime  coat  per  square  yard  of  surface  and  if  we assume a 5 percent loss factor, how many gallons of primer will be required? You can try this one on your own. ADVANCED BASE PLANNING During World War II when bases were constructed across the island chains of the Pacific Ocean, it became apparent  that  significant  savings  in  both  time  and material  could  be  realized  if  units  of  materials, equipment,  and  personnel  required  to  perform  specific functions were standardized. This was the beginning of the Advanced Base Functional Components (ABFC) System that is still in use today. In this section we will briefly discuss the ABFC System and the  Facilities Planning Guide, NAVFAC P437. ADVANCED BASE FUNCTIONAL COMPONENTS  SYSTEM A  thorough  discussion  of  the  Advanced  Base Functional Components System may be found in the Naval Construction Force (NCF) Manual,  NAVFAC P-315, and in volume II of the  Facilities   Planning Guide, NAVFAC P-437. Briefly, however, the overall ABFC System comprises a preplanned collection of individual functional components, each of which is designed  and  organized  to  perform  a  specific  function at an advanced base. These functional components are given  code  numbers  and  names  to  indicate  their function; for example, Component P-26 is a Seabee Team, and Component N-24A is a 750-man tent camp. By using the ABFC System, planners for logistics, facilities,  and  construction  can  readily  identify  the equipment,  facilities,  materials,  construction  effort,  and other pertinent information that is needed for each component. The basic document that identifies all of this data is the NAVFAC P-437. NAVFAC  P-437 The Facilities Planning Guide,  NAVFAC P-437, is the  basic  tool  that  you  should  consult  when  tasked  to assist in planning the construction of an advanced base. This  document  identifies  the  structures  and  supporting utilities  of  the  Navy  ABFC  System.  It  was  developed  to make  preengineered  facility  designs  and  corresponding material lists available to planners at all levels. While these designs relate primarily to expected needs at advanced bases and to the Navy ABFC System, they can also  be  used  to  satisfy  peacetime  requirements. Facilities, logistic, and construction planners will each find the information required to select and document the material  necessary  to  construct  facilities. NAVFAC P437 consists of two volumes. Although it  may  seem  unusual  to  do  so,  let’s  first  discuss volume II. Volume II Volume II of the P-437 is organized into three parts. Part 1 (Components) contains  data  displays  foreachof the ABFC components and is indexed by code number. These data displays list and describe the  facilities that make  up  each  ABFC  component.  Figure  5-3  is  an 5-8