2013 02 frames rev 10-06-12

Editor's Notes

• #16: ROOF SLOPE or ROOF PITCH refers to how steep the roof is Expressed as RISE over RUN Run = 12 Common roof slopes for building systems: 1/4:12 1/2:12 1:12 2:12 4:12
• #17: Eave Height is measured from the floor level (bottom of the base plate) to the eave of the building.
• #18: Eave Height is measured from the floor level (bottom of the base plate) to the eave of the building.
• #20: Varco-Pruden offers both Clear Span and Modular frame types.
• #23: Primary frames are the support members that carry most of the building loads to the foundation. VP uses 50 ksi steel for all primary framing components. Frames are coated with a Bronze primer Special colors are available, check with your division VP can manufacture frame dimensions in increments of 1/16”.
• #25: Purlins are attached to the primary frames by means of pre-punched holes. -VP uses purlin clips only in certain conditions (steep roof pitches, open web framing systems, 11 1/2” purlins etc.).
• #26: Bolting Plates are used for most primary frame connections.
• #27: Bolting Plates are used for most primary frame connections.
• #31: Clips for girt connections are factory welded.
• #33: 3. A roof pitch of 1:12 is most common. -1/2:12 is also reasonable when needed. -Roof pitches up to 4:12 & 5:12 are easy to obtain. -VP can design to almost any roof pitch required. -Less than 1/2:12 is not normally recommended (span and roof panel type must be considered). 4. Eave heights normally range from 10’ to 30’. VP has provided buildings with eave heights as high as 80’ and 100’ when required. Eave heights can be specified in 1/16” increments
• #38: Reverse Taper Columns available. The wall line is at the inside flange. Offers a smooth wall surface on the inside face with-out columns interrupting.
• #42: Hot Rolled Wide Flange members are also available.
• #45: Rigid Frames are primary frames most commonly used as interior frames.
• #47: Typical geometry of a Rigid Frame. The deepest portions of the columns and rafter generally occurs at the “haunch”. Rigid frames come standard with tapered exterior columns, but other options are available. Rigid Frames offer the advantage of economically spanning a distance without the interruption of interior columns.
• #48: The ridge does not have to be at the center of the span.
• #49: Rigid Frames can be single slope when needed.
• #53: Rigid frames transfer loads to the foundation
• #54: 1. When we need to span a distance without interior columns interrupting the span. 2. VP can provide Rigid Frames as wide as 300’. -RF’s are most economical in spans of 40’ or 50’ up to 100’ and 120’. -Exceeding this can be very expensive. -In wide span buildings, RF’s should be used only when a clear span condition is truly needed.
• #60: Continuous Beam frames are Modular frames utilizing interior columns to reduce the rafter spans, and consequently the overall cost. CB frames come standard with tapered exterior columns and “I” shaped interior columns, but other options are available.
• #62: Offset Ridge - Not A Problem
• #64: Unequal modules - Not A Problem Columns should be spaced to best suit end user and construction needs. 50’ to 60’ is usually an efficient span between columns. This varies according to loads and conditions.
• #67: Single Slope CB frames are available
• #68: 1. For wide span buildings in which interior columns are allowed. Most commonly used for large warehouses and manufacturing plants. 2. Any time the span of a rafter is decreased - it will require less steel and be lighter.
• #69: 3. We pay for steel by the pound - this will decrease the cost. 4. Continuous Beam frames are very common in widths of 60’ through 300’ (depending upon loads). It is possible to span very great widths with CB frames. VP has gone up to 800’ wide.
• #71: Unibeam frames are primary frames and serve the same purpose as a Rigid Frame or CB Frame.
• #73: This is a typical Rigid Frame. Now let’s lay a Unibeam Frame on top to see the advantages.
• #74: Unibeam frames have some advantages over Rigid Frames in certain applications: -They provide more vertical clearance near the sidewalls. -This allows for mechanical work to be above the ceiling line in small office buildings (sprinkler pipes, HVAC ductwork, etc..).
• #93: Lean-to’s attach at either the eave of the building or below the eave.
• #95: Each endwall of a building is supported by an “End Frame” .
• #96: The most common type of End Frame is a “Post & Beam” frame, when future expansion is not anticipated.
• #97: For buildings with higher eave heights and/or heavy wind loads, the Post and Beam may be made from 3-plate built-up members.
• #98: For buildings with higher eave heights and/or heavy wind loads, the Post and Beam may be made from 3-plate built-up members.
• #100: When required, another primary frame type can be placed at the endwall of a building. -This frame could be a Rigid Frame (shown) with endpost -A Unibeam Frame -A CB Frame (recommended for large spans) -Or one of VP’s Open Web frame types This frame would be used in conjunction with end posts to support the endwall girts.
• #108: Most primary frames are “Moment Resisting”. -This means that they utilize “Rigid Connections” to resist loads imposed.
• #109: Post & Beam frames are not designed to resist the wind load blowing on the sidewalls of the building.
• #111: Wind loads from the building sidewalls are usually taken to the foundation by the use of diagonal bracing or the “diaphragm action” of the endwall panels.
• #113: Rigid Frames are “Moment Resisting” frames. Rigid connections are utilized at the haunches and at the ridge. Pinned connections are used at the bases. Both vertical and horizontal loads are resisted by this configuration.