The construction of any structure or facilityis described by a set of related drawings that give the SEABEEs a complete sequential graphic description of each phase of the construction process. In most cases, a set of drawings shows the location of the project, boundaries, contours, and outstanding physical features of the construction site and its adjoining areas. Succeeding drawings give further graphic and printed instructions for each phase of construction.
TYPES OF CONSTRUCTIONDRAWINGS
Generally, construction drawings are categorized according to their intended purpose. Some of the types commonly used in military construction are discussed in this chapter.
The purpose of the PRESENTATIONDRAWINGS is to present the proposed building or facility in an attractive setting in its natural surrounding at the proposed site. They often consist of perspective views complete with colors and shading. Since presentation drawings are actually used to "sell" an idea or design concept, an EA assigned to the drafting section is rarely required to develop them.
SHOP DRAWINGS are drawings, schedules,diagrams, and other related data to illustrate a material, a product, or a system for some portion of the work prepared by the construction contractor, subcontractor, manufacturer, distributor, or supplier. Product data include brochures, illustrations, performance charts, and other information by which the work will be judged. As an EA, you will be required to draft shop drawings for minor shop and field projects. You may draw shop items, such as doors, cabinets, and small portable structures (pre-fabricated berthing quarters, and modifications of existing buildings), or perhaps you may be drawing from portions of design drawings, specifications, or from freehand sketches given by the design engineer.
MASTER PLAN DRAWINGS
MASTER PLAN DRAWINGS are commonlyused in the architectural, topographical, and construction fields. They show sufficient features to be used as guides in long-range area development. They usually contain section boundary lines, horizontal and vertical control data, acreage, locations and descriptions of existing and proposed structures, existing and proposed surfaced and unsurfaced roads and sidewalks, streams, rights-of-way and appurtenances, existing utilities, north point indicator (arrow), contour lines, and profiles. Master plan and general development drawings on existing and proposed Navy installations are maintained and constantly upgraded by the resident officer in charge of construction (ROICC) and by the public works department (PWD).
A WORKING DRAWING (also called projectdrawing) is any drawing that furnishes the information required by the craftsmen to manufacture a machine part or by a builder crew to erect a structure; it is prepared from a freehand sketch or a design drawing. Complete information is presented in a set of working drawings, complete enough that the user will require no further information. Project drawings include all the drawings necessary for the different SEABEE ratings to complete the project. These are the drawings that show the size, quantity, location, and relationship of the building components. A complete set of project drawings consists of general drawings, detail drawings, assembly drawings, and always a bill of materials. GENERAL DRAWINGS consist of "plans" (views from above) and elevations (side or front views) drawn on a relatively small defined scale, such as 1/8 in. = 1 ft or 1/4 in. = 1 ft. Most of the general drawings are drawn in orthographic projections, though sometimes details may be shown in isometric or cavalier projections. A DETAIL DRAWING shows a particular item on a larger scale than that of the general drawing in which the item appears, or it may show an item too small to appear at all on a general drawing. An ASSEMBLY DRAWING is either an exterior or a sectional view of an object showing the details in the proper relationship to one another. Usually, assembly drawings are drawn to a smaller scale than are detail drawings. This procedure provides a check on the accuracy of the design and detail drawings and often discloses errors.
Depending on the space available on the draftingsheet, you may incorporate the BILL OF MATERIALS in the drawing; otherwise, you are to list it on a separate sheet. The bill of materials contains a list of the quantities, types, sizes, and units of the materials required to construct the object presented in the drawing.
In a typical military construction, working (project)drawings go through stages of review and evaluation for design and technical adequacy by NAVFACENGCOM to ensure good quality, consistency, and cost effectiveness of the design. Special terms discussed in the following paragraphs describe these stages, from the initial development of the project to the final phase of construction.