Measurements: Between Glass. Distance across the face of any wood part that separates two sheets of glass. Face Measure. Distance across the face of any wood part, exclusive of any solid mold or rabbet. Finished Size. Dimension of any wood part overall, including the solid mold or rabbet. Wood Allowance. The difference between the outside opening and the total glass measurement of a given window or sash. Muntin. Any short light bar, either vertical or horizontal. Parting Stop. A thin strip of wood let into the jamb of a window frame to separate the sash. Pulley Stile. A side jamb into which a pulley is fixed and along which the sash slides. Rails. Cross, or horizontal, pieces of the framework of a sash or screen. Sash. A single assembly of stiles and rails made into a frame for holding glass, with or without dividing bars. It may be supplied either open or glazed. Sill. The horizontal member forming the bottom of the frame (Fig. 11.32). Stiles. Upright, or vertical, outside pieces of a sash or screen. Window. One or more single sash made to fill a given opening. It may be supplied either open or glazed. Window Unit. A combination of window frame, window, weather strip, balancing device, and at the option of the manufacturer, screen and storm sash, assembled as a complete and properly operating unit. FIGURE 11.30 Relation of modular standard double-hung wood windows to grid opening in

where p(x)  load distribution on the span [p(x)(x) is the varying force] n(x)  characteristic shape of the nth mode (see Art. 5.18.2) L  span length w  uniformly distributed weight on the span The response of the beam then is given by Eq. (5.278), and the dynamic deflection is the sum of the modal components, An n(x). Nonlinear Responses. When the structure does not react linearly to loads, the equations of motion can be solved by numerical analysis if resistance is a unique function of displacement. Sometimes, the behavior of the structure can be represented by an idealized resistance-displacement diagram that makes possible a solution in closed form. Figure 5.112a shows such a diagram. Elastic-Plastic Responses. Resistance is assumed linear (R  ky) in Fig. 5.112a until a maximum Rm is reached. After that, R remains equal to Rm for increases in y substantially larger than the displacement ye at the elastic limit. Thus, some portions of the structure deform into the plastic range. Figure 5.112a, therefore, may be used for ductile structures only rarely subjected to severe dynamic loads. When FIGURE 5.112 Response in the plastic range of a one-degree system with resistance characteristics indicated in (a) and subjected to a constant force (b) is shown in (c). this diagram can be used for designing such structures, more economical designs can be produced than for structures limited to the elastic range, because of the high energy-absorption capacity of structures in the plastic range. For a one-degree system, Eq. (5.273) can be used as the equation of motion for the initial sloping part of the diagram (elastic range). For the second stage, ye  y  ym, where ym is the maximum displacement, the equation is

A point to bear in mind is that a uniform size should be selected, if practicable, for a project, no matter what the individual functions of the different locks may be. This makes possible the use of standard-size cutouts or sinkages on each installation. When this is done, not only is the cost of installation reduced, but any changes that may be made in the drawings as the job progresses, or any changes that may have to be made later are simplified, and special hardware is avoided. Unit locks (Fig. 11.80) are complete assemblies that eliminate most of the adjustments during installation that would otherwise be necessary. These locks have merely to be slipped into a standard notch cut into a wood door or formed in a metal door. Bored-in locks are another type that can be installed by boring standard-size holes in wood doors or by having uniform circular holes formed in metal doors. These bored-in locks are often referred to as tubular-lock sets or cylindrical-lock sets depending on how the holes have to be bored to accommodate them. Tubular locks have a tubular case extending horizontally at right angles to the edge of the door. This type of case permits a horizontal hole of small diameter to be bored into the door at right angles to the vertical edge of the door; another small hole is required at right angles to the first hole to take care of the latching mechanism. Most tubular locks now produced fit the standard bores in steel doors conforming to ANSI A115.2 and A115.3, just as do cylindrical locks. FIGURE 11.81 Cylindrical lock. Cylindrical locks (Fig. 11.81), the other type of bored-in lock, have a cylindrical case requiring a relatively large-diameter hole in the door, bored perpendicular to the face of the door. This hole accommodates the main body of the lock. A hole of smaller diameter to take the latch bolt must be bored at right angles to the edge of the door. When bored-in locks are used in hollow metal doors, a reinforcing unit is required in the door. This unit is generally supplied by the door manufacturer. Exit devices are a special series of locks required by building codes and the National Fire Protection Association Life Safety Code on certain egress doors in public buildings. On the egress side, there is a horizontal bar running a minimum of one-half the width of the door. When pressed against, the bar releases the locking or latching mechanism, allowing the door to open. These devices are required to be labeled for safe egress by a nationally recognized independent testing laboratory. When used on fire doors, they must carry an additional label showing that the devices have also been investigated for fire. They then bear the name fire exit hardware. These devices are available with various functions, including arrangements for having them locked from the outside and openable with a key. For all functions, however, they must be openable from the inside by merely depressing