PIP STC01015 Structural Design Criteria

TECHNICAL CORRECTIONFebruary 2006 Process Industry Practices Structural PIP STC01015 Structural Design Criteria PURPOSE AND USE OF PROCESS INDUSTRY PRACTICES In an effort to minimize the cost of process industry facilities, this Practice has been prepared from the technical requirements in the existing standards of major industrial users, contractors, or standards organizations. By harmonizing these technical requirements into a single set of Practices, administrative, application, and engineering costs to both the purchaser and the manufacturer should be reduced. While this Practice is expected to incorporate the majority of requirements of most users, individual applications may involve requirements that will be appended to and take precedence over this Practice. Determinations concerning fitness for purpose and particular matters or application of the Practice to particular project or engineering situations should not be made solely on information contained in these materials. The use of trade names from time to time should not be viewed as an expression of preference but rather recognized as normal usage in the trade. Other brands having the same specifications are equally correct and may be substituted for those named. All Practices or guidelines are intended to be consistent with applicable laws and regulations including OSHA requirements. To the extent these Practices or guidelines should conflict with OSHA or other applicable laws or regulations, such laws or regulations must be followed. Consult an appropriate professional before applying or acting on any material contained in or suggested by the Practice. This Practice is subject to revision at any time by the responsible Function Team and will be reviewed every 5 years. This Practice will be revised, reaffirmed, or withdrawn. Information on whether this Practice has been revised may be found at www.pip.org. © Process Industry Practices (PIP), Construction Industry Institute, The University of Texas at Austin, 3925 West Braker Lane (R4500), Austin, Texas 78759. PIP member companies and subscribers may copy this Practice for their internal use. Changes, overlays, addenda, or modifications of any kind are not permitted within any PIP Practice without the express written authorization of PIP. PIP will not consider requests for interpretations (inquiries) for this Practice. PRINTING HISTORY December 1998 Issued February 2002 Technical Revision April 2002 Editorial Revision Not printed with State funds August 2004 February 2006 Complete Revision Technical Correction TECHNICAL CORRECTION February 2006 Process Industry Practices Structural PIP STC01015 Structural Design Criteria Table of Contents 1. Introduction................................. 2 1.1 Purpose ............................................. 2 1.2 Scope................................................. 2 2. References .................................. 2 2.1 Process Industry Practices (PIP)....... 2 2.2 Industry Codes and Standards.......... 2 2.3 Government Regulations................... 4 3. Definitions ................................... 5 4. Requirements.............................. 5 4.1 4.2 4.3 4.4 Design Loads..................................... 5 Load Combinations.......................... 14 Structural Design ............................. 23 Existing Structures........................... 30 Process Industry Practices Page 1 of 30 and references shall be considered an integral part of this Practice. 1.Building Data Sheets – PIP CVC01015 . Introduction 1.2 Industry Codes and Standards • American Association of State Highway and Transportation Officials (AASHTO) – AASHTO Standard Specifications for Highway Bridges • American Concrete Institute (ACI) – ACI 318/318R . and PIP CVC01018.1 Process Industry Practices (PIP) – PIP ARC01015 . The edition in effect on the date of contract award shall be used.2 Scope This Practice describes the minimum requirements for the structural design of process industry facilities at onshore U.Plant Site Data Sheet – PIP CVC01018 .Heat Exchanger and Horizontal Vessel Foundation Design Guide – PIP STS02360 . 2. PIP CVC01017. References Applicable parts of the following Practices. industry codes and standards. except as otherwise noted.Project Data Sheet – PIP PCCWE001 .Weighing Systems Guidelines – PIP REIE686/API 686 . 2. Short titles will be used herein where appropriate. as applicable.Architectural and Building Utilities Design Criteria – PIP ARC01016 . This Practice is intended to be used in conjunction with PIP ARC01015.Blast Resistant Building Design Criteria – PIP STE05121 . PIP CVC01015.Anchor Bolt Design Guide – PIP STE03360 .Civil Design Criteria – PIP CVC01017 .Recommended Practices for Machinery Installation and Installation Design – PIP STC01018 .Building Code Requirements for Structural Concrete and Commentary Page 2 of 30 Process Industry Practices .Weighing Systems Criteria – PIP PCEWE001 .S.1 Purpose This Practice provides structural engineering design criteria for the process industries. sites. PIP ARC01016.Driven Piles Specification 2.PIP STC01015 Structural Design Criteria TECHNICAL CORRECTION February 2006 1. Standard Specification for Alloy-Steel and Stainless Steel Bolting Materials for High-Temperature Service Process Industry Practices Page 3 of 30 . Part I .TECHNICAL CORRECTION February 2006 PIP STC01015 Structural Design Criteria – ACI 350R .Minimum Design Loads for Buildings and Other Structures – SEI/ASCE 37-02 .Safety Code for Elevators and Escalators • ASTM International (ASTM) – ASTM A36/A36M .Load and Resistance Factor Design (LRFD) – Specification for Structural Joints Using ASTM A325 or A490 Bolts – ANSI/AISC 341-02 . for Concrete Reinforcement – ASTM A185/A185M .1 .Allowable Stress Design (ASD) – AISC Manual of Steel Construction .Design Loads on Structures During Construction – ASCE Guidelines for Seismic Evaluation and Design of Petrochemical Facilities – ASCE Guidelines for Wind Loads and Anchor Bolt Design for Petrochemical Facilities – ASCE Design of Blast Resistant Buildings in Petrochemical Facilities • American Society of Mechanical Engineers (ASME) – ASME A17.Seismic Provisions for Structural Steel Buildings • American Iron and Steel Institute (AISI) – AISI SG 673. Plain.Welded Steel Tanks for Oil Storage • American Society of Civil Engineers (ASCE) – SEI/ASCE 7-02 . for Concrete – ASTM A193/A193M . Part II .Commentary on the Specification for the Design for Cold-Formed Steel Structural Members – AISI SG 913.Standard Specification for Carbon Structural Steel – ASTM A82/A82M .Standard Specification for Steel Wire.Building Code Requirements for Masonry Structures • American Institute of Steel Construction (AISC) – AISC Manual of Steel Construction .Load and Resistance Factor Design Specification for Cold-Formed Steel Structural Members – AISI SG 913. Part I . Plain.Environmental Engineering Concrete Structures – ACI 530/ASCE 5 . Part II .Standard Specification for Steel Welded Wire Reinforcement.Commentary on the Load and Resistance Factor Design Specification for Cold-Formed Steel Structural Members • American Petroleum Institute (API) – API Standard 650 .Specification for the Design for Cold-Formed Steel Structural Members – AISI SG 673. Load Tables and Weight Tables for Steel Joists and Joist Girders 2.Design Values for Wood Construction • Crane Manufacturers Association of America (CMAA) – CMAA No.1M .Standard Specification for Quenched and Tempered Alloy Steel Bolts.Standard Specification for Structural Steel Shapes – ASTM F1554 . Heat Treated 830 MPa Minimum Tensile Strength [Metric] – ASTM A354 .Specifications for Top Running Bridge and Gantry Type Multiple Girder Overhead Electric Traveling Cranes – CMAA No.Standard Specification for Anchor Bolts.: M 164 – ASTM A325M . 74 . Page 4 of 30 Process Industry Practices . 36.Standard Specification for Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement – ASTM A706/A706M .AASHTO No.Specifications for Top Running and Under Running Single Girder Overhead Electric Traveling Cranes Utilizing Under Running Trolley Hoist • Precast/Prestressed Concrete Institute (PCI) – PCI MNL 120 .Standard Specification for Structural Bolts.: M 253 – ASTM A615/A615M .Standard Specification for Carbon Steel Bolts and Studs.Standard Specification for Structural Bolts. 60. 120/105 ksi Minimum Tensile Strength .Steel • American Forest and Paper Association – National Design Specification for Wood Construction (NDS) – NDS Supplement . Steel.Standard Specification for Structural Bolts.Design Handbook .PIP STC01015 Structural Design Criteria TECHNICAL CORRECTION February 2006 – ASTM A307 .150 ksi Minimum Tensile Strength . Heat Treated. 70 . Steel.AASHTO No. including any additional requirements by state or local agencies that have jurisdiction in the state where the project is to be constructed. Heat Treated.000 psi Tensile Strength – ASTM A325 .Structural Welding Code . Studs. and 105-ksi Yield Strength • American Welding Society (AWS) – AWS D1.Standard Specification for Low-Alloy Steel Deformed and Plain Bars for Concrete Reinforcement – ASTM A992/A992M . and Other Externally Threaded Fasteners – ASTM 490 . Steel.1/D1. shall apply.3 Government Regulations Federal Standards and Instructions of the Occupational Safety and Health Administration (OSHA). 55.Precast and Prestressed Concrete • Steel Joist Institute (SJI) – SJI Standard Specifications. Alloy Steel. 4. 4. local building codes.3 Future loads shall be considered if specified by the owner. earth pressure. Df. shall be considered.1.1 Dead loads are the actual weight of materials forming the building.1. structure.1.S. platforms.2.1.2 In addition to the loads in this section. De. piping.2.2 Dead Loads (D) 4. 4.Safety and Health Regulations for Construction 3. Department of Labor.1. rain. dead loads are designated by the following nomenclature: Ds. other loads shall be considered as appropriate. where Ds = Structure dead load is the weight of materials forming the structure (not the empty weight of process equipment. and Dt. snow.1. vehicles. and all permanently attached appurtenances.5 Eccentric loads (piping.1. valves. Process Industry Practices Page 5 of 30 .2 Weights of fixed process equipment and machinery. etc. this section and the loads defined in PIP CVC01017 and CVC01018. Definitions engineer of record: The owner’s authorized representative with overall authority and responsibility for the structural design owner: The party who owns the facility wherein structure will be used 4.1.TECHNICAL CORRECTION February 2006 PIP STC01015 Structural Design Criteria • U. 4. including floor slabs and foundations. ice. shall be designed to resist the minimum loads defined in SEI/ASCE 7.1 Design Loads 4.1.1 New facilities.1. Do. foundation.Occupational Safety and Health Standards – OSHA 29 CFR 1926 . These loads shall include. particularly on horizontal and vertical vessels and exchangers. and the contents of these items shall be considered as dead loads.1. 4.3 For this Practice.1.1. 4. buildings.2. but are not limited to.1 General 4. and erection.). and other structures.1. hydrostatic. Occupational Safety and Health Administration (OSHA) – OSHA 29 CFR 1910 . actual loads may be used in lieu of the minimum specified loads. For additional information regarding eccentric loads on horizontal vessels and exchangers. 4. dynamic. electrical cable trays.1. buoyancy.4 For existing facilities. see PIP STE03360. upset conditions. Requirements 4. etc. HVAC. trays. Unless otherwise specified. and all permanently attached appurtenances (e. Dt = Test dead load is the empty weight of process equipment.4 Process Equipment and Vessel Dead Loads 1. platforms.4). vessels.g.4 through 4. fireproofing.2. tanks. and insulation. soil above the foundation resisting uplift.6).PIP STC01015 Structural Design Criteria TECHNICAL CORRECTION February 2006 vessels.2. lighting. piping. piping. Test dead load (Dt) for process equipment and vessels is the empty dead load plus the weight of test medium contained in the system. 3.2.1.). insulation.7). fireproofing. The test medium shall be as specified in the contract documents or as specified by the owner. and/or piping plus the weight of the test medium contained in the system (as further defined in Section 4. piping. and packaged units).0 shall be used for the test medium.4).1. Equipment and pipes that may be simultaneously tested shall be included. Operating dead load (Do) for process equipment and vessels is the empty dead load plus the maximum weight of contents (including packing/catalyst) during normal operation.4 through 4. tanks. Cleaning load shall be used for test dead load if the cleaning fluid is heavier than the test medium. De = Empty dead load is the empty weight of process equipment. 4. foundation. tanks. a minimum specific gravity of 1.2. piping.1. compressors. 2.1. Df = Erection dead load is the fabricated weight of process equipment or vessels (as further defined in Section 4. vessels. and cable trays plus the maximum weight of contents (fluid load) during normal operation (as further defined in Sections 4.2. Empty dead load also includes weight of machinery (e. vessels. Empty dead load (De) for process equipment and vessels is the empty weight of the equipment or vessels. 4. etc. tanks. instrumentation. ladders. nor cable trays). Erection dead load (Df) for process equipment and vessels is normally the fabricated weight of the equipment or vessel and is generally taken from the certified equipment or vessel drawing.1. Do = Operating dead load is the empty weight of process equipment.. Page 6 of 30 Process Industry Practices .g. turbines.2. sprinkler and deluge systems. agitators.1. including all attachments. pumps.. and cable trays (as further defined in Sections 4.1.2. internals. Operating dead load (Do): A uniformly distributed load of 40 psf (1. unless actual load information is available and requires otherwise: a. the actual configuration) should be considered as the empty dead load. product.1.TECHNICAL CORRECTION February 2006 PIP STC01015 Structural Design Criteria 4.2. 2.2. product. Dead loads for piping on pipe racks shall be estimated as follows.6 Pipe Rack Cable Tray Loads Dead loads for cable trays on pipe racks shall be estimated as follows. The test medium shall be as specified in the contract documents or as specified by the owner.1. c.e. and insulation Comment: This is equivalent to 8-inch (203-mm) diameter. including the weight of piping. This load shall be uniformly distributed over the pipe’s associated area. b. a reduced level of cable tray load (i. at 15-inch (381-mm) spacing. 3.0 kPa) for a single level of cable trays and 40 psf (1. Operating dead load (Do): A uniformly distributed dead load of 20 psf (1.5 Pipe Rack Piping Loads 1. Unless otherwise specified. Process Industry Practices Page 7 of 30 . fittings.9 kPa) for a double level of cable trays. Pipe racks and their foundations shall be designed to support loads associated with full utilization of the available rack space and any specified future expansion. For any pipe larger than 12-inch (304-mm) nominal diameter. b. full of water. unless actual load information is available and requires otherwise: a. 60% of the estimated piping operating loads shall be used if combined with wind or earthquake unless the actual conditions require a different percentage. Empty dead load (De): For checking uplift and components controlled by minimum loading.. a minimum specific gravity of 1.9 kPa). and insulation shall be used in lieu of the 40 psf (1. Comment: These values estimate the full (maximum) level of cables in the trays. 4.9 kPa) for piping. a concentrated load. Test dead load (Dt) is the empty weight of the pipe plus the weight of test medium contained in a set of simultaneously tested piping systems. Engineering judgement shall be exercised in defining the dead load for uplift conditions. Empty dead load (De): For checking uplift and components controlled by minimum loading. Schedule 40 pipes. valves.0 shall be used for the test medium. 3 Live Loads (L) 4.g. wheel loads.1. 4. in addition to the fluid load from the test medium.0 shall be used for the test medium. heat exchanger tube bundle servicing) shall be designed to support the live loads. discussed as follows: a. such as personnel.7 Ground-Supported Storage Tank Loads Dead loads for ground-supported storage tanks are shown in Table 9 with the same nomenclature as other dead loads in this Practice for consistency. the metal dead load and the fluid load must be used separately in design. the metal dead load and the fluid load must be used separately in design. etc. The test medium shall be as specified in the contract documents or as specified by the owner. vertically applied through the wall of the tank. These include the weight of all movable loads.3.PIP STC01015 Structural Design Criteria TECHNICAL CORRECTION February 2006 4. a minimum specific gravity of 1. in addition to the fluid load from the stored product. Therefore.1.1. b. movable partitions. 4. miscellaneous equipment. Test dead load (Dt): Test dead load for a ground-supported storage tank is made up of the metal load from the tank shell and roof.1. the corroded metal weight (if a corrosion allowance is specified) should be considered as the empty dead load. Therefore.3. Empty dead load (De): For checking uplift and components controlled by minimum loading.2.3 Minimum live loads shall be in accordance with SEI/ASCE 7. The fluid load acts through the bottom of the tank and does not act vertically through the wall of the tank. The fluid load acts through the bottom of the tank and does not act vertically through the wall of the tank.. in Table 1: Page 8 of 30 Process Industry Practices . c. unless otherwise specified. vertically applied through the wall of the tank. 4.1 Live loads are gravity loads produced by the use and occupancy of the building or structure.2 Areas specified for maintenance (e.1. tools.3. The individual load components making up the dead loads may have to be separated for actual use in design. parts of dismantled equipment. Unless otherwise specified. and. applicable codes and standards. stored material. Operating dead load (Do): Operating dead load for a groundsupported storage tank is made up of the metal load from the tank shell and roof. 4.1.1.5 kN) 1. 4.4 Wind Loads (W) 4.1. MINIMUM LIVE LOADS Uniform** Stairs and Exitways Operating.3.0 kN/m2) 250 psf (12.1 Unless otherwise specified.1.4 Uniform and concentrated live loads listed in Table 1 shall not be applied simultaneously. 4.1.5 kN) 1.8 kN/m2) 2 Concentrated** 1.5 kN) NA 100 psf (4. Process Industry Practices Page 9 of 30 .5 kN) *This 250 psf (12.3.3.10 The loadings on handrails and guardrails for buildings and structures under the jurisdiction of a building code shall be in accordance with the building code. 4.6 kN/m2) 100 psf (4.9 The loadings on handrails and guardrails for process equipment structures shall be in accordance with OSHA 1910.5 ft (750 mm) and shall be located to produce the maximum load effects in the structural members.8 For manufacturing floor areas not used for storage.000 lb (4.3.1. 4. 4. 4.8 kN/m ) 75 psf (3. and pipe racks in ASCE Guidelines for Wind Loads and Anchor Bolt Design for Petrochemical Facilities.0 kN) 3. concentrated loads equal to or greater than 1.1.6 Stair treads shall be designed according to OSHA regulations or building code as applicable.000 lb (4.3.7 Live load reductions shall be in accordance with SEI/ASCE 7.000 lb (4.0 kN/m2)* 25 psf (1.3. 4. wind loads shall be computed and applied in accordance with SEI/ASCE 7 and the recommended guidelines for open frame structures.1.5 According to SEI/ASCE 7. pressure vessels.3.2 kN/m2) 2. I/O.000 lb (13.000 lb (4.000 lb (9. **The loads provided in this table are to be used unless noted otherwise on the owner’s data sheet. and Walkways Control.5 kN) may be assumed to be uniformly distributed over an area of 2.4. the live load reduction specified by SEI/ASCE 7 for lower live loads may be used.0 kN/m2) live load includes small equipment.5 ft (750 mm) by 2. Access Platforms. HVAC Room Floors Manufacturing Floors and Storage Areas: Light Heavy Ground-Supported Storage Tank Roof 125 psf (6.TECHNICAL CORRECTION February 2006 PIP STC01015 Structural Design Criteria TABLE 1.1. The design wind speed shall be 68 mph (109 kph) (which is 0.1. 4.5.5. 4.2 Site specific design parameters shall be in accordance with PIP CVC01017. earthquake loads shall be computed and applied in accordance with SEI/ASCE 7.1.6).4.4.3 The owner shall be consulted for the determination of the classification category.1 Except for API Standard 650 ground-supported storage tanks.1. Section 6.1. 4. Earthquake loads for API Standard 650 storage tanks are allowable stress design loads.5.1.4. designed for earthquakes according to SEI/ASCE 7.3 ASCE Guidelines for Seismic Evaluation and Design of Petrochemical Facilities may also be used as a general reference for earthquake design.6 Partial wind load (WP) shall be based on the requirements of SEI/ASCE 37-02. and this should be taken into account if using allowable stress design methods or applying load factors from other codes.1. unless otherwise specified. are typically classified as Category III. Section 6.5 ft (450 mm) shall be assumed when calculating the wind load on ladder cages.2 and Table 1-1.1.A).S. 4.5 A solid width of 1.4 The full design wind load shall be used when calculating wind drift (see Section 4. In some cases. for specific details. 4.1. Section 1.2 Site specific design parameters shall conform to PIP CVC01017. SEI/ASCE 7 Category III is the most likely classification because of the presence of hazardous materials.1.2.1.4. 4. see SEI/ASCE 37-02. Comment: Buildings and building-like structures.1. for the specified test or erection duration.3. See SEI/ASCE 7-02. Comment: For process industry facilities.4.4.2. Page 10 of 30 Process Industry Practices .5. Category II may be used if the owner can demonstrate that release of the hazardous material does not pose a threat to the public. In some cases. 4.7 For test or erection periods of 6 weeks or more or if the test or erection is in a hurricane-prone area and is planned during the peak hurricane season (from August 1 to October 31 in the U. it may be appropriate to select Category IV. Comment: The earthquake loads in SEI/ASCE 7 are limit state earthquake loads.75 x 90 mph [145 kph] according to SEI/ASCE 37 for test or erection periods of less than 6 weeks).1.5 Earthquake Loads (E) 4. it may be appropriate to select Category IV.PIP STC01015 Structural Design Criteria TECHNICAL CORRECTION February 2006 4. 4. 6 For the load combinations in Section 4. and cooling towers.1.3 Lifting lugs or pad eyes and internal members (included both end connections) framing into the joint where the lifting lug or pad eye is located shall be designed for 100% impact.1. Table 9. in some cases.1.5.14.4 All other structural members transmitting lifting forces shall be designed for 15% impact. it may be appropriate to select seismic use group I or III. pipe racks. Comment: In general. if SEI/ASCE 7 is used for the earthquake design of nonbuilding structures as defined in SEI/ASCE 7-02.1. 4.5. however.5.TECHNICAL CORRECTION February 2006 PIP STC01015 Structural Design Criteria 4.1.14. 4. Section 9.1. horizontal vessels. giving an importance factor “I” of 1.6. or heat exchangers caused by the thermal expansion of the pipe attached to the vessel Process Industry Practices Page 11 of 30 . for nonbuilding structures in petrochemical process units. 4. 4.6.14. 4. select seismic use group II. T.2 Impact loads for davits shall be the same as those for monorail cranes (powered).7.1.1.1.5.7 Thermal Loads 4. and Ff.5. 4. stacks.6. where Tp = Forces on vertical vessels.1.6. Comment: Nonbuilding structures include but are not limited to elevated tanks or vessels.1. 4.1.14. Af.25.1 and Table 9.4 Earthquake loading shall be determined using SEI/ASCE 7-02. Section 9. the following designations are used: Eo = Earthquake load considering the unfactored operating dead load and the applicable portion of the unfactored structure dead load Ee = Earthquake load considering the unfactored empty dead load and the applicable portion of the unfactored structure dead load 4.6.5 The importance factor “I” for nonbuilding structures shall be determined from SEI/ASCE 7-02. thermal loads are designated by the following nomenclature: Tp.1.1.2.1 For this Practice.1.6 Impact Loads 4.5 Allowable stresses shall not be increased when combining impact with dead load.2.1 Impact loads shall be in accordance with SEI/ASCE 7. 4. and structural members in pipe racks or in structures Af = Pipe anchor and guide forces Ff = Pipe rack friction forces caused by the sliding of pipes or friction forces caused by the sliding of horizontal vessels or heat exchangers on their supports. anchor and guide loads (excluding their friction component) shall be combined with wind or earthquake loads. To account for the significant increase in temperatures of steel exposed to sunlight. However. columns.5 Friction loads caused by thermal expansion shall be determined using the appropriate static coefficient of friction.7. 4.7 For pipe racks supporting multiple pipes. in response to thermal expansion 4.1.PIP STC01015 Structural Design Criteria TECHNICAL CORRECTION February 2006 T= Self-straining thermal forces caused by the restrained expansion of horizontal vessels. 35oF (20oC) shall be added to the maximum ambient temperature. “Teflon”) 0. heat exchangers.4 0. Comment: Under normal loading conditions with multiple pipes.7.3 Thermal loads shall be included with operating loads in the appropriate load combinations. Thermal load shall have the same load factor as dead load.g.7. 4.1.7.6 Friction loads shall be considered temporary and shall not be combined with wind or earthquake loads.7. 10% of the total piping weight shall be used as an estimated horizontal friction load applied only to local supporting beams.7. and foundations. torsional effects on the local beam need not be considered because the pipes supported by the beam limit the rotation of the beam to the extent that the torsional stresses are minimal. 4. However.1.2 All support structures and elements thereof shall be designed to accommodate the loads or effects produced by thermal expansion and contraction of equipment and piping.1.1. an estimated friction load equal to 5% of the total piping weight shall be accumulated and carried into pipe rack struts. COEFFICIENTS OF FRICTION Steel to Steel Steel to Concrete Proprietary Sliding Surfaces or Coatings (e. braced anchor frames.4 Thermal loads and displacements shall be calculated on the basis of the difference between ambient or equipment design temperature and installed temperature. Coefficients of friction shall be in accordance with Table 2: TABLE 2.6 According to Manufacturer’s Instructions 4..1. Under certain Page 12 of 30 Process Industry Practices . braced anchor frames.000 lb (9.8. 4. 4. 4.1. the bundle pull design load need not exceed the total weight of the exchanger.9 Internal pressure and surge shall be considered for pipe anchor and guide loads. struts.0 times the weight of the removable tube bundle but not less than 2.7.1.3 The portion of the bundle pull load at the sliding end support shall equal the friction force or half the total bundle pull load.7.1. 4. trenches.1.9 Traffic Loads 4.000 lb (9. 4.7.3 Truck or crane loads shall have the same load factor as live load.1. engineering judgement shall be applied to determine whether a higher friction load and/or torsional effects should be used. 4.1 Structures and foundations supporting heat exchangers subject to bundle pulling shall be designed for a horizontal load equal to 1.1. Such assurance would typically require the addition of a sign posted on the exchanger to indicate bundle removal by an extractor only.1.0 kN). 4. columns. whichever is less.1. only the top flange shall be considered effective for horizontal bending unless the pipe anchor engages both flanges of the beam.1.8 Pipe anchor and guide loads shall have the same load factor as dead loads.8 Bundle Pull Load (Bp) 4. If the total weight of the exchanger is less than 2. Process Industry Practices Page 13 of 30 . and underground installations accessible to truck loading shall be designed to withstand HS20 load as defined by AASHTO Standard Specifications for Highway Bridges.2 Bundle pull load shall be applied at the center of the bundle.7.1.8. 4. and foundations shall be designed to resist actual pipe anchor and guide loads.8.2 Maintenance or construction crane loads shall also be considered where applicable. The remainder of the bundle pull load shall be resisted at the anchor end support.0 kN).11 For local beam design.1 Buildings.9.10 Beams. Comment: If it can be assured that the bundles will be removed strictly by the use of a bundle extractor attaching directly to the exchanger (such that the bundle pull force is not transferred to the structure or foundation).1. the structure or foundation need not be designed for the bundle pull force. 4. 4.9.TECHNICAL CORRECTION February 2006 PIP STC01015 Structural Design Criteria circumstances.9.1. Appropriate load combinations from SEI/ASCE 7 except as otherwise specified in this Practice b.2.11 Pressure Loads (Ground-Supported Tanks Only) For this Practice. Any other applicable design codes and standards d.2.1 Unless otherwise specified.6 for specific types of structures in both allowable stress design (ASD) and strength design format. Allowable Stress Design Page 14 of 30 Process Industry Practices .2.10.12.1. where Pi = design internal pressure Pe = external pressure Pt = test internal pressure 4.2 Typical Load Combinations (for Structures and Foundations) 4. Pe. 4. Any other probable and realistic combination of loads 4.1.2 Site specific design parameters shall be in accordance with PIP CVC01017. 4.1 Blast load is the load on a structure caused by overpressure resulting from the ignition and explosion of flammable material or by overpressure resulting from a vessel burst.1 General Load combinations are provided in Sections 4. snow loads shall be computed and applied in accordance with SEI/ASCE 7.1.1. Local building codes c. structures.1.3 Blast load shall be computed and applied in accordance with PIP STC01018 and the ASCE Design of Blast Resistant Buildings in Petrochemical Facilities.2.2. and foundations shall be designed for the following: a. vessels.1.2.2 through 4.2 Control houses or other buildings housing personnel and control equipment near processing plants may need to be designed for blast resistance.10. 4. tanks. pressure loads for ground-supported tanks are designated by the following nomenclature: Pi.2. a. 4. equipment.2.1.2 Load Combinations 4. 4.10.12.10 Blast Load 4.1 General Buildings.PIP STC01015 Structural Design Criteria TECHNICAL CORRECTION February 2006 4.1. and Pt.12 Snow Loads (S) 4. 9 instead of 1.2 through 4. 4.0 is used for the wind uplift ASD load combinations because of the higher accuracy of dead loads of nonbuilding structures. because the dead loads of nonbuilding structures are known to a higher degree of accuracy than are the corresponding dead loads of buildings. b. Section 2. The noncomprehensive list of typical load combinations for each type of structure provided in Sections 4. The following load combinations are appropriate for use with the strength design provisions of either AISC LRFD (third edition or later) or ACI 318 (2002 edition or later). Steel structures in Seismic Design Category D or higher shall use factored load combinations as specified in ANSI/AISC 341-02. are generally not required to consider the effect of vertical seismic uplift forces if a dead load factor of 0. A dead load factor of 0. This factor is greater than the 0.2. except for foundations for ground-supported storage tanks.9. A dead load factor of 1. 2.6 is used. Section 2. 3. The use of this reduction is necessary because foundations sized using ASD loads. The use of a one-third stress increase for load combinations including wind or earthquake loads shall not be allowed for designs using the AISC ASD.2 General Plant Structures Load combinations for buildings and open frame structures shall be in accordance with SEI/ASCE 7-02. Engineering judgment shall be used in establishing all appropriate load combinations.2. Part III (Allowable Stress Design Alternative).2. Strength Design 1.2.2. 3. The noncomprehensive list of typical factored load combinations for each type of structure provided in Sections 4.6 dead load factor used in the ASD load combinations of SEI/ASCE 7-02.2. Process Industry Practices Page 15 of 30 .6 shall be considered and used as applicable.2.2.0 is used to account for the effect of vertical seismic forces.6 shall be considered and used as applicable. Engineering judgment shall be used in establishing all appropriate load combinations.2 through 4.TECHNICAL CORRECTION February 2006 PIP STC01015 Structural Design Criteria 1.2. Comment: The dead load factor used for the seismic uplift ASD load combinations is generally taken as 0.2. 4. 2. 3.PIP STC01015 Structural Design Criteria TECHNICAL CORRECTION February 2006 4. if deemed advisable. Thrust forces caused by thermal expansion of piping shall be included in the calculations for operating load combinations.14.7. the critical earthquake provisions and implied load combination of SEI/ASCE 7-02.7 Eea 1.00 1.2. LOADING COMBINATIONS .20 Notes: a.00 6 Ds + Dt + Wp 1. The pipe stress engineer shall be consulted for any thermal loads that are to be considered. b. Page 16 of 30 Process Industry Practices .00 Load Combination Ds + Do + L Ds + Do + (W or 0. Erection weight + partial wind is required only if the erection weight of the vessel is significantly less than the empty weight of the vessel.7 Eoa) Ds + De + W Description Operating Weight + Live Load Operating Weight + Wind or Earthquake Empty Weight + Wind (Wind Uplift Case) Operating Weight + Earthquake (Earthquake Uplift Case) Empty Weight + Earthquake (Earthquake Uplift Case) Erection Weight + Partial Windb (Wind Uplift Case) Test Weight + Partial Wind 4a 0.00 4b 0. For skirt-supported vertical vessels and skirt-supported elevated tanks classified as SUG III in accordance with SEI/ASCE 7-02.9 (Ds + Do) + 0. Section 9.10.ALLOWABLE STRESS DESIGN (SERVICE LOADS) Load Comb.00 1. Section 9.00 5 Ds + Df + Wp 1. c.9 (Ds + De) + 0.7 Eoa 1.3 Vertical Vessels TABLE 3. shall be followed. No.2. 1 2 3 Allowable Stress Multiplier 1.5. The pipe stress engineer shall be consulted for any thermal loads that are to be considered. c.9 (Ds + De) + 1.7.0 Eoa 0.14.TECHNICAL CORRECTION February 2006 PIP STC01015 Structural Design Criteria TABLE 4.9 (Ds + Df) + 1.9 (Ds + Do) + 1. Process Industry Practices Page 17 of 30 .0 Eea 0.6 W or 1. No. the critical earthquake provisions and implied load combination of SEI/ASCE 7-02.2 (Ds + Do) + 1.6 L 1. shall be followed. 1 2 3 4 5a 5b 6 7 8 Load Combination 1. if deemed advisable.6 Wp 1.2 (Ds + Do) + (1. LOADING COMBINATIONS AND LOAD FACTORS – STRENGTH DESIGN Load Comb.2 (Ds + Dt) + 1.0 Eoa) 0.10. Thrust forces caused by thermal expansion of piping shall be included in the calculations for operating load combinations.4 (Ds + Do) 1.5.9 (Ds + De) + 1. Erection weight + partial wind is required only if the erection weight of the vessel is significantly less than the empty weight of the vessel. b. Section 9.6 Wp Description Operating Weight Operating Weight + Live Load Operating Weight + Wind or Earthquake Empty Weight + Wind (Wind Uplift Case) Operating Weight + Earthquake (Earthquake Uplift Case) Empty Weight + Earthquake (Earthquake Uplift Case) Erection Weight + Partial Windb (Wind Uplift Case) Test Weight Test Weight + Partial Wind Notes: a. Section 9. The same load factor as used for dead load shall be used.6 W 0.3. For skirt-supported vertical vessels and skirt-supported elevated tanks classified as SUG III in accordance with SEI/ASCE 7-02.4 (Ds + Dt) 1. 1 Load Combination Ds + Do + (T or Ff)b Ds + Do + L + (T or Ff)b Allowable Stress Multiplier 1. Sustained thermal loads not relieved by sliding caused by vessel or exchanger expansion shall be considered in operating load combinations with wind or earthquake. d. but shall not necessarily be applied simultaneously.7 Eo) Ds + De + W 1. No. LOADING COMBINATIONS .7 Ee Ds + Df + Wp 1.00 5b 1.00 6 1.9 (Ds + De) + 0.9 (Ds + Do) + 0. Heat exchanger empty dead load will be reduced during bundle pull because of the removal of the exchanger head.00 Description Operating Weight + Thermal Expansion or Friction Force Operating Weight + Live Load + Thermal Expansion or Friction Force Operating Weight + Wind or Earthquake Empty Weight + Wind (Wind Uplift Case) Operating Weight + Earthquake (Earthquake Uplift Case) Empty Weight + Earthquake (Earthquake Uplift Case) Erection Weight + Partial Windc (Wind Uplift Case) Test Weight + Partial Wind (For Horizontal Vessels Only) Empty Weight + Bundle Pull (For Heat Exchangers Only) 2 1. Erection weight + partial wind is required only if the erection weight of the vessel or exchanger is significantly less than the empty weight of the vessel or exchanger.7 Eo 0.00 3 Ds + Do + (W or 0.ALLOWABLE STRESS DESIGN (SERVICE LOADS) Load Comb. e.00 5a 0. Wind and earthquake forces shall be applied in both transverse and longitudinal directions. The design thermal force for horizontal vessels and heat exchangers shall be the lesser of T or Ff.00 Notes: a.2.PIP STC01015 Structural Design Criteria TECHNICAL CORRECTION February 2006 4.00 7 Ds + Dt + Wp 1.00 4 1.2.4 Horizontal Vessels and Heat Exchangers TABLE 5. Page 18 of 30 Process Industry Practices . b. c.20 8 Ds + De + Bp d 1. Thrust forces caused by thermal expansion of piping shall be included in the calculations for operating load combinations if deemed advisable.6 W 3 4 5a 0.9 (Ds + Ded) + 1.6 Bp 9 10 Notes: a.2 (Ds + Dt) + 1. Wind and earthquake forces shall be applied in both transverse and longitudinal directions.6 Bp 0. but shall not necessarily be applied simultaneously. The pipe stress engineer shall be consulted for any thermal loads that are to be considered. Process Industry Practices Page 19 of 30 . LOADING COMBINATIONS AND LOAD FACTORS – STRENGTH DESIGN Load Comb.9 (Ds + De) + 1.6 Wp 7 1.9 (Ds + Do) + 1. c.6 W or 1.2 (Ds + Ded) + 1.9 (Ds + De) + 1. No. Heat exchanger empty dead load will be reduced during bundle pull because of the removal of the exchanger head.2 (Ds + Do) + (1.4 (Ds + Do) + 1. The design thermal force for horizontal vessels and heat exchangers shall be the lesser of T or Ff.6 Wp 1. 1 Load Combination 1. d.9 (Ds + Df) + 1.0 Ee 6 0.TECHNICAL CORRECTION February 2006 PIP STC01015 Structural Design Criteria f. Erection weight + partial wind is required only if the erection weight of the vessel or exchanger is significantly less than the empty weight of the vessel or exchanger.0 Eo) 0.2 (T or Ff)b 1.0 Eo 5b 0.4 (Ds + Dt) 8 1. b.4 (T or Ff) b Description Operating Weight + Thermal Expansion or Friction Force Operating Weight + Live Load + Thermal Expansion or Friction Force Operating Weight + Wind or Earthquake Empty Weight + Wind (Wind Uplift Case) Operating Weight + Earthquake (Earthquake Uplift Case) Empty Weight + Earthquake (Earthquake Uplift Case) Erection Weight + Partial Windc (Wind Uplift Case) Test Weight (For Horizontal Vessels Only) Test Weight + Partial Wind (For Horizontal Vessels Only) Empty Weight + Bundle Pull (For Heat Exchangers Only) Empty Weight + Bundle Pull (For Heat Exchangers Only) (Bundle Pull Uplift Case) 2 1.6 L + 1. TABLE 6.2 (Ds + Do) + 1. Considerations of wind forces are normally not necessary in the longitudinal direction because friction and anchor loads will normally govern. 0. if deemed advisable. The pipe stress engineer shall be consulted for any thermal loads that are to be considered. 1 Allowable Stress Multiplier 1.00 3 4a 1.00 1. Full Ds + Do value shall be used for the calculation of Eo in load combination 4a. The same load factor as used for dead load shall be used.00 5 Ds + Dt + Wp 1. No.9 (Ds) + 0. LOADING COMBINATIONS .2.7 Eod 1. e.PIP STC01015 Structural Design Criteria TECHNICAL CORRECTION February 2006 e. d. Earthquake forces shall be applied in both transverse and longitudinal directions. c.7 Ee 1.ALLOWABLE STRESS DESIGN (SERVICE LOADS) Load Comb.6 (Do) + Af + 0.20 Notes: a. b.00 Load Combination Ds + Do + Ff + T + Af Description Operating Weight + Friction Force + Thermal Expansion + Anchor Force Operating Weight + Anchor + Wind or Earthquake Empty Weight + Wind (Wind Uplift Case) Operating Weight + Earthquake (Earthquake Uplift Case) Empty Weight + Earthquake (Earthquake Uplift Case) Test Weight + Partial Winde 2 Ds + Do + Af + (W or 0.6Do is used as a close approximation of the empty pipe condition De.2. f. Thrust forces caused by thermal expansion of piping shall be included in the calculations for operating load combinations. Test weight + partial wind normally is required only for local member design because test is not typically performed on all pipes simultaneously. but shall not necessarily be applied simultaneously.5 Pipe Rack and Pipe Bridge Design TABLE 7. Page 20 of 30 Process Industry Practices . Sustained thermal loads not relieved by sliding from vessel or exchanger expansion shall be considered in operating load combinations with wind or earthquake.7 Eo) Ds + Dec + W 0.00 4b 0.9 (Ds + Dec) + 0. 4. 0 Eo) 0. but shall not necessarily be applied simultaneously.0 Eo 3 4a 4b 5 6 0.9 (Ds + Dec) + 1.2 (Ds + Dt) + 1. 1 Load Combination 1.9 (Ds + Dec) + 1. d. 0.2 (Ds + Do + Af) + (1.6 Ground-Supported Storage Tank Load Combinations Load combinations for ground-supported storage tanks shall be taken from API Standard 650. b.TECHNICAL CORRECTION February 2006 PIP STC01015 Structural Design Criteria TABLE 8. Process Industry Practices Page 21 of 30 .2 (Af) + 1.6 W 0.6 W or 1. Considerations of wind forces are normally not necessary in the longitudinal direction because friction and anchor loads will normally govern.4 (Ds + Do + Ff + T + Af) Description Operating Weight + Friction Force + Thermal Expansion + Anchor Operating Weight + Anchor + Wind or Earthquake Empty Weight + Wind (Wind Uplift Case) Operating Weight + Earthquake (Earthquake Uplift Case) Empty Weight + Earthquake (Earthquake Uplift Case) Test Weight Test Weight + Partial Windd 2 1. Test weight + partial wind normally is required only for local member design because test is not typically performed on all pipes simultaneously. LOADING COMBINATIONS AND LOAD FACTORS STRENGTH DESIGN Load Comb.2. Earthquake forces shall be applied in both transverse and longitudinal directions. Load combinations from API Standard 650 and modified for use with SEI/ASCE 7 loads and PIP nomenclature are shown in Table 9.6 Wp Notes: a. 4.9 (Ds + Do) + 1.6Do is used as a close approximation of the empty pipe condition De. c.0 Ee 1.2. No.4 (Ds + Dt) 1. ALLOWABLE STRESS DESIGN (SERVICE LOADS) Load Comb. anchor bolts.4.2. Filters. the owner shall consider specifying a higher factor on design pressure in load combinations 3. 4.PIP STC01015 Structural Design Criteria TECHNICAL CORRECTION February 2006 TABLE 9.2. For internal pressures sufficient to lift the tank shell according to the rules of API Standard 650.4 Pib Description Operating Weight + Internal Pressurea Test Weight + Test Pressure Empty or Operating Weight + Wind + Internal Pressurea Empty or Operating Weight + Wind + External Pressure Operating Weight + Live or Snow + External Pressure Empty or Operating Weight + Live or Snow + External Pressure Operating Weight + Snow + Earthquake + Internal Pressurea (Earthquake Uplift Case) Operating Weight + Snow + Earthquake 4 Ds + (De or Do) + W + 0. Skid and Modular Equipment.4 Peb 5 Ds + Do + (L or S) + 0. and Other Equipment Load combinations for static machinery. LOADING COMBINATIONS . 5. Earthquake loads for API Standard 650 tanks taken from SEI/ASCE 7 “bridging equations” or from API Standard 650 already include the 0.4 Pib 8 Ds + Do + 0.7 ASD seismic load factor. and 7 of Table 9. 4.. 1 2 3 Load Combination Ds + Do + Pi Ds + Dt + Pt Ds + (De or Do) + W + 0.7 Load Combinations for Static Machinery.1 Engineering judgment shall be used in establishing the appropriate application of test load combinations to adequately address actual Page 22 of 30 Process Industry Practices . etc. 4. and foundation shall be designed to the additional requirements of API Standard 650 Appendix F. c. If the ratio of operating pressure to design pressure exceeds 0.7. skid and modular equipment.2.3 Test Combinations 4.3.4 Peb 6 Ds + (De or Do) + 0. No. b.1 S + Eoc + 0. tank.4 (L or S) + Pe 7 Ds + Do + 0.2. filters.1 S + Eoc Notes: a. shall be similar to the load combinations for vertical vessels. Posts (which weigh less than 300 lb [136 kg]) are distinguished from columns and are excluded from the fouranchor bolt requirement. 4.4 Additional loading shall be included with test if specified in the contract documents.3.2. Comment: Supplement number 1 to the AISC ASD specification deleted the one-third stress increase for use with load combinations including wind or earthquake loads. a 20% allowable stress increase shall be permitted for any test load combination. vessels. 4.2 Consideration shall be given to the sequence and combination of testing for various equipment. if a significant probability exists that the “partial wind velocity” will be exceeded or an earthquake event may occur). and their foundations shall be designed to resist a minimum eccentric gravity load of 300 lb (136 kg) located 18 inches (450 mm) from the extreme outer Process Industry Practices Page 23 of 30 .3. Comment: Common requirements that affect steel design areas follow (this is not an all inclusive list): a. shall be designed in accordance with OSHA 29 CFR 1926.1. and/or piping systems supported on common structures.1. b. column base plates.2 For cold-formed shapes. pipe racks. or foundations.3. 4. All column base plates shall be designed with a minimum of four anchor bolts.2.3. tanks.5 For allowable stress design.2. 4.3 Steel joists shall be designed in accordance with SJI standards.3. to provide structural stability during erection and to protect employees from the hazards associated with steel erection activities.1 Steel design shall be in accordance with AISC ASD or AISC LRFD specifications.1 Steel 4.3 Structural Design 4.3 Full wind and earthquake loads are typically not combined with test loads unless an unusually long test duration is planned (i.3. 4. no load factor reduction shall be permitted for any test load combination.1. 4.3..2. 4.e. 4. Columns.TECHNICAL CORRECTION February 2006 PIP STC01015 Structural Design Criteria test conditions in accordance with project and code requirements while avoiding overly conservative design. designs made to the AISC LRFD specifications should be considered for economy. including steel joists and metal decking. Subpart R.2.6 For ultimate strength/limit states design.1. 4.3. design shall be in accordance with AISI specifications. Because of the deletion of the one-third stress increase.4 Steel design.3.3. 4. joists.11 Except as specified in Section 4.3.1.1. all bolts 3/4 inches (19 mm) and larger (except anchor bolts) shall be type-N (bearing-type with threads included in the shear plane) high-strength ASTM A325 bolts.1). 4. Section 3. The openings in the metal deck shall not be cut until the hole is needed. The fabricator may also supply a seat or equivalent device with a means of positive attachment to support the first beam while the second beam is being erected. e.12 Bolt size shall be as follows: Page 24 of 30 Process Industry Practices . except where not allowed by design constraints or constructability. Double connections through column webs or at beams that frame over the tops of columns shall be designed so that at least one installed bolt remains in place to support the first beam while the second beam is being erected. and have an electrode strength of 58 ksi (400 MPa) minimum yield strength and 70 ksi (480 MPa) tensile strength. or beam attachments until after the metal decking or other walking/working surface has been installed. 4. not supporting equipment.3.1.8 Preference in design shall be given to shop-welded.1/D1. 4.1. 4. c. Column splices shall be designed to meet the same loadresisting characteristics as those of the columns.3.1M.12 or if slip-critical connections are required by the AISC Specification for Structural Joints Using ASTM A325 or A490 Bolts.6 Structural steel wide-flange shapes.3.200 mm) above the finished floor (unless constructability does not allow) to allow the installation of perimeter safety cables. Structural members of framed metal deck openings shall be turned down to allow continuous decking. 4. unless otherwise specified.1. f. and bars shall be in accordance with ASTM A36/A36M.10 Grating shall not be considered as lateral bracing for support beams. shall be in accordance with ASTM A992/A992M.3.1. Perimeter columns shall extend 48 inches (1.3. Provision shall be made for the attachment of safety cables. 4.3.3 (including Table 3. unless otherwise specified. unless otherwise required.7 All other structural shapes.9 Compression flanges of floor beams.PIP STC01015 Structural Design Criteria TECHNICAL CORRECTION February 2006 face of the column in each direction at the top of the column shaft.1. plates. d.5 All welded structural connections shall use weld filler material conforming to AWS D1.1. 4. may be considered braced by decking (concrete or floor plate) if positively connected thereto. Shear stud connectors that will project vertically from or horizontally across the top flange of the member shall not be attached to the top flanges of beams. including WT shapes.3.3.1. field-bolted connections. 4.2.25.3. 4.3.TECHNICAL CORRECTION February 2006 PIP STC01015 Structural Design Criteria a. (16 mm) ASTM A307 4. ladders.4 Elevator Supports Elevator support design shall be in accordance with ASME A17. all reinforcing steel shall be in accordance with ASTM A615/A615M Grade 60 deformed.3 Unless otherwise specified. Structural members .3. without impact (where L = the span length). ASTM A615/A615M Grade 60 reinforcement is acceptable for these members under the following conditions: a.3.2 Concrete design for liquid-containing structures shall also be designed in accordance with ACI 350R.7 MPa).1 Vertical deflection of support runway girders shall not exceed the following limits given in Table 10 if loaded with the maximum wheel load(s).2.3. The actual yield strength based on mill tests does not exceed the specified yield strength by more than 18.5/8 inch.2.3. 4.7 Precast and prestressed concrete shall be in accordance with the PCI Design Handbook.000 psi (20.3 Masonry Masonry design shall be in accordance with ACI 530/ASCE 5.2. and girts . 4.1. The ratio of the actual ultimate tensile strength to the actual tensile yield strength is not less than 1.1.13 Minimum thickness of bracing gusset plates shall be 3/8 inch (10 mm).3/4 inch (19 mm) minimum b. Retests shall not exceed this value by more than an additional 3.3.3.4 ASTM A615/A615M Grade 60 plain wire conforming to ASTM A82/A82M may be used for spiral reinforcement.5 Welded wire fabric shall conform to ASTM A185/A185M. 4.000 psi (124 MPa). 4.1 Concrete design shall be in accordance with ACI 318/318R. b.3.5.6 Reinforcement designed to resist earthquake-induced flexural and axial forces in frame members and in wall boundary elements shall be in accordance with ASTM A706/A706M.2.2 Concrete 4.3. purlins. Railings.3.2. 4.3. 4.5 Crane Supports 4. 4. Process Industry Practices Page 25 of 30 . 4.2.3. 3.6.5.8 m/sec2) Length of travel (ft) of spring or plunger required to stop crane. and C Cranes Monorails L/600 L/800 L/1000 L/450 L/450 4. kips (kN) 50% of bridge weight + 90% of trolley weight. B.6.3. B.3. from crane manufacturer.5 for helical springs.2 Except as indicated in the following subsections. Page 26 of 30 Process Industry Practices . for the following load: F = W V2/(2gTn) where: F W V g T = = = = = Design force on crane stop. if not specified.15 ft (0.2 Vertical deflection of jib crane support beams shall not exceed L/225 (where L = the maximum distance from the support column to load location along the length of the jib beam) if loaded with the maximum lifted plus hoist load(s). 4. and C Cranes Top-Running CMAA Class D Cranes Top-Running CMAA Class E and F Cranes Under-Running CMAA Class A.4 Crane stops shall be designed in accordance with the crane manufacturer’s requirements or. 4.) n = 4.1 Allowable wind drift limits for pipe racks shall not exceed H/100 (where H = pipe rack height).3. the allowable wind story drift limits for occupied buildings shall not exceed H/200 (where H = story height). ft/sec (m/sec) Acceleration of gravity.5. Consult crane manufacturer for hydraulic plunger.05 m) Bumper efficiency factor (0. kips (kN) Rated crane speed.2 ft/sec2 (9. typically 0. MAXIMUM ALLOWABLE GIRDER DEFLECTIONS Top-Running CMAA Class A.3.3.3 Lateral deflection of support runway girders for cranes with lateral moving trolleys shall not exceed L/400 (where L = the span length) if loaded with a total crane lateral force not less than 20% of the sum of the weights of the lifted load (without impact) and the crane trolley. 4.5. excluding the lifted load.6 Allowable Drift Limits 4. The lateral force shall be distributed to each runway girder with consideration for the lateral stiffness of the runway girders and the structure supporting the runway girders. without impact. 32.PIP STC01015 Structural Design Criteria TECHNICAL CORRECTION February 2006 TABLE 10. 3.3 Allowable wind drift limits for pre-engineered metal buildings shall not exceed H/80 (where H = building height). the minimum overturning “stability ratio” shall be 1. whichever is less (see Section 4.3.5 Allowable wind drift limits for buildings with bridge cranes that will not be in service during hurricanes shall not exceed H/140 or 2 inches (50 mm).3. 4.6.4 for the minimum sliding factor of safety for earthquake loads).1 Foundation design shall be based on the results of a geotechnical engineering investigation. Comment: This requirement is consistent with SEI/ASCE 7 provisions.3.6.3 The minimum factor of safety against sliding for service loads other than earthquake shall be 1.6 Allowable wind drift limits for process structures and personnel access platforms shall not exceed H/200 (where H = structure height at elevation of drift consideration). in which the “factor of safety” is built into the 0.6.6. 4.6 “dead load factor” in the load combinations.3.7 Allowable seismic drift limits shall be in accordance with SEI/ASCE 7.6. Section 9. the minimum factor of safety against sliding shall be 1.6 in accordance with SEI/ASCE 7-02.3.7. The minimum overturning “stability ratio” and the minimum factor of safety against sliding for earthquake service loads shall be 1.2 The minimum overturning “stability ratio” for service loads other than earthquake shall be 1.7. Comment: This requirement is consistent with SEI/ASCE 7 provisions.0.5 (see Section 4. 4. 4.3.4 for definition of H).7.4 Overturning and sliding caused by earthquake loads shall be checked in accordance with SEI/ASCE 7-02.3. Section 2.7.7.TECHNICAL CORRECTION February 2006 PIP STC01015 Structural Design Criteria 4. For foundation design of buildings and open frame structures.6.0. Section 2. For foundation design of buildings and open frame structures. In addition. if the dead load factor is 0.7. 4.6 “dead load factor” in the load combinations. if the dead load factor is 0.7 Foundations 4. the minimum overturning “stability ratio” for the anchorage and Process Industry Practices Page 27 of 30 .3.0.5 (see Section 4.3.4 Allowable wind drift limits for a building with a bridge crane that is required to be in service even during hurricanes shall not exceed H/400 or 2 inches (50 mm).3. 4. whichever is less (where H = the height from the base of the crane support structure to the top of the runway girder). 4.3. 4.4 for the minimum overturning “stability ratio” for earthquake loads).6 in accordance with SEI/ASCE 7-02. in which the “factor of safety” is built into the 0.3. 6. equipment manufacturer’s recommendations.5.7.8.6.15 inch (3. 4. 4. Section 9.10 Except for foundations supporting ground-supported storage tanks. 4. and 7 of this Practice. E.3.12 inch (3.8. 4.7.7.5.2 If equipment manufacturer’s vibration criteria are not available.5.9 Unless otherwise specified.11 Foundations for ground-supported storage tanks that have sufficient internal pressure to lift the shell shall be designed for the requirements of API Standard 650 Appendix F.7.525 mm) deep or greater and because it is costly to shore excavations.8.7. 4.2 if using actual unfactored service loads. Section 9. 4. “Overturning.5 For earthquake loads calculated by the “Equivalent Lateral Force Procedure” in SEI/ASCE 7.3 Support structures or foundations for centrifugal machinery greater than 500 horsepower shall be designed for the expected dynamic forces using dynamic analysis procedures.7.14. shall be 1.5.2 for the critical earthquake loads specified in SEI/ASCE 7-02. minimizing the depth of spread footings shall be considered in the design. if used to size foundations. settlementsensitive equipment or piping systems. “Overturning. Section 9. Section 9. 4. the maximum velocity of movement during steady-state normal operation shall be limited to 0. additional stability checks shall be done in accordance with SEI/ASCE 7-02.5. Section 9.PIP STC01015 Structural Design Criteria TECHNICAL CORRECTION February 2006 foundations of skirt-supported vertical vessels and skirt-supported elevated tanks classified as SUG III in accordance with SEI/ASCE 7-02. the reduction in the foundation overturning moment permitted in SEI/ASCE 7-02.3.3. 4.10.7. the top of grout (bottom of base plate) of pedestals and ringwalls shall be 1 ft (300 mm) above the high point of finished grade.7.5.8 Because OSHA requires shoring or the equivalent for excavations 5 ft (1.3.3. Section 9.8 Supports for Vibrating Machinery 4.” shall not be used. 5.3.3.3.” For foundations designed using seismic load combination from Tables 3.1 Machinery foundations shall be designed in accordance with PIP REIE686. and published design procedures and criteria for dynamic analysis. 4.6 The minimum factor of safety against buoyancy shall be 1.3.3.7.7 Long-term and differential settlement shall be considered if designing foundations supporting interconnected.3. Chapter 4.8 mm) per second for reciprocating machines.0 mm) per second for centrifugal machines and to 0. uplift load combinations containing earthquake loads do not need to include the vertical components of the seismic load effect. 4.3. Page 28 of 30 Process Industry Practices . 4 For centrifugal machinery less than 500 horsepower. Process Industry Practices Page 29 of 30 . A307.3.9.12 Design of Driven Piles 4.3 Reinforcing steel shall allow a minimum of 3 inches (75 mm) of concrete cover on piers without casing and 4 inches (100 mm) of concrete cover on piers in which the casing will be withdrawn.TECHNICAL CORRECTION February 2006 PIP STC01015 Structural Design Criteria 4. 4. 4.7 The maximum eccentricity between the center of gravity of the combined weight of the foundation and machinery and the bearing surface shall be 5% in each direction. unless specified otherwise by the equipment manufacturer. or A354 Grade BD material. F1554 Grade 36. 4.11. F1554 Grade 105.3. the foundation weight shall be designed to be at least five times the total machinery weight. 4.11 Design of Drilled Shafts 4. the foundation weight shall be designed to be at least three times the total machinery weight.11. unless specified otherwise by the manufacturer.3. 4. and F1554 Grade 36 anchor bolts shall be hot dip galvanized. A354 Grade BC.3. 4. 4.9.1 Anchor bolts shall be headed type or threaded rods with compatible nuts using ASTM A36/A36M.3 Anchor bolt design shall be in accordance with PIP STE05121. 4.8 Structures and foundations that support vibrating equipment shall have a natural frequency that is outside the range of 0.Design Values for Wood Construction.12.8.3.9.3.50% of the pier gross area or as required to resist axial loads and bending moments.8.2 All ASTM A36/A36M.9 Anchor Bolts 4.3.1 Minimum vertical reinforcement shall be 0.3.3. in the absence of a detailed dynamic analysis.8.80 to 1.6 The allowable soil-bearing or allowable pile capacity for foundations for equipment designed for dynamic loads shall be a maximum of half of the normal allowable for static loads.3.20 times the exciting frequency.5 For reciprocating machinery less than 200 horsepower.10 Wood Wood design shall be in accordance with the American Forest and Paper Association National Design Specification for Wood Construction and with the NDS Supplement .3.8. in the absence of a detailed dynamic analysis. 4.2 The minimum clear spacing of vertical bars shall not be less than three times the maximum coarse aggregate size nor less than three times the bar diameter. 4. the pile types specified in PIP STS02360 shall be used.3.3. F1554 Grade 55.3.8.1 Unless otherwise specified or approved. A307. A193/A193M Grade B7.11. 4.3.3. 4. and installation stresses.3. no further analysis is required.4.PIP STC01015 Structural Design Criteria TECHNICAL CORRECTION February 2006 4. 4. 4.3.4 Existing Structures If the owner and the engineer of record agree that the integrity of the existing structure is 100% of the original capacity based on the design code in effect at the time of original design. 4.12. 4. transportation.4.4. The strength of any structural element or connection shall not be decreased to less than that required by the applicable design code or standard for new construction for the structure in question.4 The top of piles shall penetrate a minimum of 4 inches (100 mm) into the pile cap.13 Vessel Load Cell Supports Supports for vessel load cells shall be designed in accordance with PIP PCCWE001 and PIP PCEWE001.2 4.12. If the increased forces on the element or connection are greater than 5%. piles shall be designed to resist handling.3. the exposure condition shall be evaluated to establish the corrosion allowances for steel piles. 4.3 Page 30 of 30 Process Industry Practices . structural designs shall be performed in accordance with the following: 4.3.3 Unless otherwise specified.12.1 If additions or alterations to an existing structure do not increase the force in any structural element or connection by more than 5%.2 In addition to in-place conditions. the element or connection shall be analyzed to show that it is in compliance with the applicable design code for new construction.