Inflection Point Engineering Section 4 — Structures and Foundations

Design Criteria and Loads for Structures

IPE Engineering Practice IPE-EP-4-1-1

Document number: IPE-EP-4-1-1 · Section: 4 — Structures and Foundations

TABLE 7 LOAD CASE COMBINATIONS AND DESIGN CRITERIA FOR STRUCTURAL ELEMENTS (CONTINUED) 25

TABLE 8 UNIFORMLY DISTRIBUTED PIPING DEAD LOADS FOR OPEN FRAME STRUCTURES 24 TABLE 9 DESIGN FORCES FOR FLARE PIPING SYSTEMS 26

TABLE 10 COEFFICIENTS OF STATIC FRICTION 27

TABLE 11 ASCE 7 WIND LOADING DESIGN PARAMETERS (1) 27

TABLE 12 ASCE 7 SEISMIC LOAD COEFFICIENTS 28

TABLE 13 DOCUMENTATION REQUIREMENTS FOR DESIGN CRITERIA AND LOADS FOR STRUCTURES PER EP 4-1-1 29

SCOPE

2.0 REFERENCES

The latest edition of the following standards and publications are referred to herein.

STANDARDS AND PUBLICATIONS

IPE Engineering Practices
EP 1-1-3 Deviations to IPE Engineering Practices
EP 4-1-2 Requirements for Blast Resistant Buildings and
EP 4-2-3 Structures Reinforced Concrete Foundations
EP 4-2-8 Support Structures and Foundations for Heavy Machinery
EP 4-3-1 Concrete Design
EP 4-5-1 Structural Steel
EP 4-5-3 Auxiliary Structures for Operation and Maintenance
EP 4-6-1 General Requirements for Buildings
EP 4-7-1 Steel Stacks
EP 5-1-3 Piping Stress Analysis and Supports
EP 7-1-1 Pressure Vessels
EP 9-1-1 Atmospheric Storage Tanks
EP 9-2-1 Low Pressure Storage Tanks
ACI Publications
318 Building Code Requirements for Reinforced Concrete
530 Building Code Requirements for Masonry Structures

STANDARDS AND PUBLICATIONS (CONT.)

AISC Publication
Manual of Steel Construction, Allowable Stress Design
Manual of Steel Construction, Load and Resistance Factor Design
API
RP 579 Fitness-for-Service
Std 620 Design and Construction of Large, Welded, Low-Pressure Storage Tanks Std 650 Welded Steel Tanks for Oil Storage
ASCE
7 Minimum Design Loads for Buildings and Other Structures
"Wind Loads and Anchor Bolt Design for Petrochemical Facilities"
ASME Codes and Standards
Sec. VIII Pressure Vessels Code, Divisions 1
Sec. VIII Pressure Vessels Code, Alternative Rules, Division 2 B31.3 Process Piping
STS-1 Steel Stacks
Building Codes
ICBO Uniform Building Code
International Building Code
OSHA
Rules and Regulations
Publication
Bednar, H. H., "Pressure Vessel Design Handbook", Van Nostrand Reinhold, 1981.
Deghetto, K., and Long, W., "Dynamic Stability Design of Stacks and Towers", Transactions of the ASME, November, 1966.

DEFINITIONS

STRUCTURAL DESIGN CRITERIA

DEAD LOADS

LIVE LOADS

FLUID LOADS

THERMAL, FRICTION, AND SETTLEMENT LOADS

RAIN LOADS

WIND LOADS

6.5.13 of ASCE 7 using the column marked "Open buildings and other structures". The projected area normal to the wind, Af, shall be based on the largest pipe diameter including insulation and jacketing. Note that for piping analysis the wind force is expressed as a force per unit length.

11.3.3. The force coefficient shall be 0.6 if the height to diameter ratio is less than 7.0, and 0.7 if the height to diameter ratio equals 25.0. For height to diameter ratios greater than 7.0 and less than 25.0, the force coefficient shall be determined by interpolation. This method shall be limited to equipment with circular platforms whose width does not exceed 4 feet.

Figure

where

DE  Equivalent Outside Diameter (ft)

D  Outside Diameter of Equipement including Insulation (ft) S  Average platform spacing (ft)

M1  Platform Factor, 0 for no platforms, 0.04 with platforms M 2  Piping ping Factor, 0 for no piping, 0.16 with piping

K1  Platform Factor, 0 for no platforms,1.59 with platforms

K 2  Ladder Factor, 0 for no ladders,1.89  0.1(S - 22) with ladders

DE  1.5D for D  3 feet 1.4D for 3  D  5 feet 1.3D for 5  D  7 feet 1.2D for D  7 feet

Figure

f0  678.5 D2

where,

t  thickness of structure at height under consideration (in.)

D  outside diameter at height under consideration ( ft.)

Resonance occurs if the frequency of the lowest mode of ovaling vibration is twice the vortex shedding frequency, or the critical velocity for ovaling is, VO (ft./sec):

Figure

EARTHQUAKE LOADS

BLAST LOADS

SOIL, HYDROSTATIC PRESSURE AND FLOOD LOADS

LOAD CASE COMBINATION AND DESIGN CRITERIA

accordance with the AISC Specification or ACI code, and to check the stability of structures against overturning. The consideration of a load case in ASCE 7 not specifically addresses in Table 7 shall be approved by the Owner's Engineer. These may include, but are not limited to, load cases involving flood and/or hydrostatic (or hydrodynamic) loads.

Engineering Practices listed in Table 1.

DEFLECTION LIMITS

FOUNDATION LOADS

17.0 TABLES

TABLE 1

DESIGN CRITERIA FOR STRUCTURES

Structural System Applicable Industry Standard Applicable
IPE Engineering Practice
Reinforced Concrete:
Foundations		 ACI 318 EP 4-2-3
Support Structures and Foundations for Heavy Machinery ACI 318 EP 4-2-8
Structural Steel: Buildings and Pipe Supports AISC Manual of Steel Construction EP 4-5-1, EP 4-6-1
Structural Steel: Platforms and Walkways AISC Manual of Steel Construction EP 4-5-1, EP 4-5-3
Reinforced Concrete: Buildings and Pipe Supports ACI 318 EP 4-3-1, EP 4-6-1
Reinforced Masonry Structures ACI 530 EP 4-6-1
Steel Stacks ASME STS-1 EP 4-7-1
Piping Systems ASME B31.3 EP 5-1-3
Pressure Vessels ASME Code, Section VIII EP 7-1-1
Low-Pressure Storage Tanks (API-620) API Std 620 EP 9-2-1
Atmospheric Storage Tanks (API-650) API Std 650 EP 9-1-1

TABLE 2

MINIMUM LIVE LOADING REQUIREMENTS FOR DESIGN OF STRUCTURAL FRAMING

Structural Component Minimum Live Load
Walkways and Floor Plate or Grating(1) 75 psf(2)
Platform Framing(1) 75 psf(2) or a concentrated load of 2,000 lb. applied over an area of 2-1/2 sq. ft., or the actual equipment weight, whichever is greater (Located so as to produce the maximum load effects in structural members)
Warehouse, Storage Areas, Loading Platforms, and Slab on Grade 250 psf or wheel loading, including impact, of material-handling equipment expected to be operated in the area, whichever
is greater
Ladders A moving concentrated load of 500 lb.
Stairs A moving concentrated load of 1,000 lb or 50 psf on the horizontal projection applied vertically, whichever is more severe
Guard Railing and Posts for Platforms and Stairway Shall meet OSHA requirements, Section 1910.23e

NOTES:

TABLE 3

MINIMUM DESIGN IMPACT LOADS

Handling Facility Load Application Impact Load
Traveling Crane Runway Vertical on the supports
Longitudinal on the supports

Lateral on the supports		 *25% of the lifted load

10% of the maximum wheel loads applied at the top of the runway

20% of the sum of the lifted load and the weight (mass) of the crane trolley applied at the top of the runway, one half on each side, and considered as acting in either direction normal to the runway
Trolley Beams Vertical on trolley beams
Longitudinal on trolley beams		 25% of the lifted load

10% of the wheel loads
Davits Vertical on the davit
Lateral on the davit		 25% of the lifted load

20% of the weight (mass) of the moving equipment
Elevators Vertical on the supports 100% of rated capacity

* Must be verified to see if this agrees with the requirements of ASCE 7 (ref sect.4.10)

TABLE 4

MINIMUM WHEEL IMPACT LOADS

Vehicle Type Impact Load
Vehicles with Pneumatic Tires 30% of Equipment Weight
Vehicles with Solid Tires 50% of Equipment Weight

TABLE 5

VALUE OF THE STRUCTURAL DAMPING COEFFICIENT (BETA) FOR VERTICAL PRESSURE VESSELS

Description Beta ()
Empty steel vessel without internals 0.0048
Empty steel vessel with trays spaced more than 5 feet 0.0051
Empty steel vessel with trays spaced more than 3 feet but less than or equal to 5 feet 0.0056
Empty steel vessel with trays spaced less than or equal to 3 feet 0.0064
Steel vessel with trays spaced more than 5 feet but less than or equal to 8 feet and with operating liquid in trays 0.0116
Steel vessel with trays spaced less than or equal to 5 feet and with operating liquid in trays 0.0127
Vessel full of liquid 0.018

TABLE 6

VALUE OF THE STRUCTURAL DAMPING COEFFICIENT (BETA) FOR STACKS

Stack Configuration Beta ()
Stacks Supported At Grade: 0.004



0.001
0.002
0.002
0.003


0.008
Minimum Value-All welded, unlined stack, with a shallow 0.004



0.001
0.002
0.002
0.003


0.008
foundation on rock or firm soil 0.004



0.001
0.002
0.002
0.003


0.008
Additional Damping, added to a minimum value, due to: 0.004



0.001
0.002
0.002
0.003


0.008
Foundation (piled or shallow)on soft soil 0.004



0.001
0.002
0.002
0.003


0.008
Stack lining, at least 2 inches thick 0.004



0.001
0.002
0.002
0.003


0.008
Stack with at least 5 bolted, unwelded, flanges 0.004



0.001
0.002
0.002
0.003


0.008
Ducts entering top 60% of slack height from at 0.004



0.001
0.002
0.002
0.003


0.008
least two direction between 60 and 120 apart 0.004



0.001
0.002
0.002
0.003


0.008
Maximum Value, including above additions 0.004



0.001
0.002
0.002
0.003


0.008
Stacks on Elevated Supports:
Minimum Value-All welded, unlined stack, on bare steel support structure

Additional Damping, added to minimum value, due to: Refractory lining added to steel support
Stack lining, at least 2 inches thick (1)
Stack with at least 5 bolted, unwelded, flanges (1)

Maximum Value, including above additions		 0.003
Stacks on Elevated Supports:
Minimum Value-All welded, unlined stack, on bare steel support structure

Additional Damping, added to minimum value, due to: Refractory lining added to steel support
Stack lining, at least 2 inches thick (1)
Stack with at least 5 bolted, unwelded, flanges (1)

Maximum Value, including above additions		 0.002
Stacks on Elevated Supports:
Minimum Value-All welded, unlined stack, on bare steel support structure

Additional Damping, added to minimum value, due to: Refractory lining added to steel support
Stack lining, at least 2 inches thick (1)
Stack with at least 5 bolted, unwelded, flanges (1)

Maximum Value, including above additions		 0.001 - 0.002
Stacks on Elevated Supports:
Minimum Value-All welded, unlined stack, on bare steel support structure

Additional Damping, added to minimum value, due to: Refractory lining added to steel support
Stack lining, at least 2 inches thick (1)
Stack with at least 5 bolted, unwelded, flanges (1)

Maximum Value, including above additions		 0.001 - 0.003
Stacks on Elevated Supports:
Minimum Value-All welded, unlined stack, on bare steel support structure

Additional Damping, added to minimum value, due to: Refractory lining added to steel support
Stack lining, at least 2 inches thick (1)
Stack with at least 5 bolted, unwelded, flanges (1)

Maximum Value, including above additions		 0.008
All Cases:
Maximum Value, with addition of at least 3 guy wires
temporarily attached to top one-third of stack during erection 0.012
Maximum Value, with addition of damping pads (2) 0.020

NOTES:

TABLE 7

LOAD CASE COMBINATIONS AND DESIGN CRITERIA FOR STRUCTURAL ELEMENTS

Loading Condition Design Loads and Forces (1)
(All loads and forces are additive)		 Design Stresses and Load Factors (3) (Structural steel and reinforced concrete)
Erection Dead load of structure less: fireproofing and piping. Dead load of equipment, less: all loose internals, insulation and platforms supported from the equipment.

Temporary loads and forces caused by erection.

Full wind or earthquake, whichever is greater.		 AISC Specification or ACI 318
Testing or Flushing Equipment Plus Reduced Occasional Dead load of structure, plus fire- proofing. Dead load of equipment, including: all internals, insulation, and platforms supported from the equip- ment. Dead load of piping, plus insulation.

Applicable live loads excluding vibration, surge, maintenance and roof live loads.

Fluid load (water) for testing or flushing equipment and piping unless pneumatic test is specified.

Wind load for a wind speed of 35 mph.		 AISC Specification, or ACI 318 plus the following provisions for structures supporting equipment subject to water test, wherein all or a majority of the
fluid load is water applied for a relatively short time.
t Allowable Stress Design(AISC). Basic allow-able stresses may be increased 20% when wind loading is excluded
t Strength Design (ACI). All load factors may be multiplied by 0.83 when wind loading is excluded, and 0.75 when wind loading is included.
t Load and Resistance Design (AISC). For all loads, use a load factor of 1.4 when wind loading is excluded, and 1.3 when wind loading is included.

TABLE 7

LOAD CASE COMBINATIONS AND DESIGN CRITERIA FOR STRUCTURAL ELEMENTS (CONTINUED)

Loading Condition Design Loads and Forces (1)
(All loads and forces are additive)		 Design Stresses and Load Factors (3) (Structural steel and reinforced concrete)
Normal Operation Dead load of structure, plus fire- proofing. Dead load of equipment, including: all internals, insulation, and platforms supported from the equipment. Dead load of piping, plus insulation

Applicable live loads excluding roof live loads and surge loads (2)

Fluid load during normal operation.

Thermal, friction, and settlement loads.

Roof live load or rain load, whichever is greater.		 AISC Specification or ACI 318

TABLE 7

LOAD CASE COMBINATIONS AND DESIGN CRITERIA FOR STRUCTURAL ELEMENTS (CONTINUED)

Loading Condition Design Loads and Forces (1)
(All loads and forces are additive)		 Design Stresses and Load Factors (3) (Structural steel and reinforced concrete)
Normal Operation plus Occasional Dead load of structure, plus fire- proofing. Dead load of equipment, including: all internals, insulation, and platforms supported from the equipment. Dead load of piping, plus insulation.

Applicable live loads excluding roof live loads (2).		 AISC Specification or ACI 318 plus the following provisions when surge load is combined with wind or earthquake loads (4):

t Allowable Stress Design(AISC). Basic allow-able stresses may be increased in accordance with ASCE 7.
3. Normal surge forces. t Strength Design (ACI). All load factors may be multiplied by 0.75, but net load
factors shall not be reduced below 1.0.
4. Fluid load during normal operation
5. Thermal, friction, and settlement loads. t Load and Resistance Design (AISC).
Use a load factor of 1.15 on all loads..
6. Roof live load, snow load or rain load, whichever is greater.
7. Full wind or earthquake, whichever is greater.

TABLE 7

LOAD CASE COMBINATIONS AND DESIGN CRITERIA FOR STRUCTURAL ELEMENTS (CONTINUED)

Loading Condition Design Loads and Forces (1)
(All loads and forces are additive)		 Design Stresses and Load Factors (3) (Structural steel and reinforced concrete)
Abnormal Operation or Startup
plus Reduced Occasional		 1. Dead load of structure plus fire- proofing. Dead load of equipment, including: all internals, insulation, and platforms supported form the equipment. Dead load of piping, plus insulation. AISC Specification or ACI 318 plus the following provisions when surge load is combined with wind loads (4):

t Ulitmate Stress Design (AISC). The basic allowable stresses may be increased 50%, but not above the yield point of the material.

t Ultimate Strength Design (ACI). All load factors may be multiplied by 0.75, but net load factors shall not be reduced below 1.0.

t Load and Resistance Factor Design (AISC). Use a load factor of 1.15 on all loads.
2. Applicable live loads excluding roof live loads and surge loads (2). AISC Specification or ACI 318 plus the following provisions when surge load is combined with wind loads (4):

t Ulitmate Stress Design (AISC). The basic allowable stresses may be increased 50%, but not above the yield point of the material.

t Ultimate Strength Design (ACI). All load factors may be multiplied by 0.75, but net load factors shall not be reduced below 1.0.

t Load and Resistance Factor Design (AISC). Use a load factor of 1.15 on all loads.
3. Abnormal surge forces. AISC Specification or ACI 318 plus the following provisions when surge load is combined with wind loads (4):

t Ulitmate Stress Design (AISC). The basic allowable stresses may be increased 50%, but not above the yield point of the material.

t Ultimate Strength Design (ACI). All load factors may be multiplied by 0.75, but net load factors shall not be reduced below 1.0.

t Load and Resistance Factor Design (AISC). Use a load factor of 1.15 on all loads.
4. Fluid load during normal operation, startup or upset, whichever is greatest. AISC Specification or ACI 318 plus the following provisions when surge load is combined with wind loads (4):

t Ulitmate Stress Design (AISC). The basic allowable stresses may be increased 50%, but not above the yield point of the material.

t Ultimate Strength Design (ACI). All load factors may be multiplied by 0.75, but net load factors shall not be reduced below 1.0.

t Load and Resistance Factor Design (AISC). Use a load factor of 1.15 on all loads.
5. Thermal, friction, and settlement loads. AISC Specification or ACI 318 plus the following provisions when surge load is combined with wind loads (4):

t Ulitmate Stress Design (AISC). The basic allowable stresses may be increased 50%, but not above the yield point of the material.

t Ultimate Strength Design (ACI). All load factors may be multiplied by 0.75, but net load factors shall not be reduced below 1.0.

t Load and Resistance Factor Design (AISC). Use a load factor of 1.15 on all loads.
6. Roof live load, snow load or rain load, whichever is greater. AISC Specification or ACI 318 plus the following provisions when surge load is combined with wind loads (4):

t Ulitmate Stress Design (AISC). The basic allowable stresses may be increased 50%, but not above the yield point of the material.

t Ultimate Strength Design (ACI). All load factors may be multiplied by 0.75, but net load factors shall not be reduced below 1.0.

t Load and Resistance Factor Design (AISC). Use a load factor of 1.15 on all loads.
7. Wind load for a wind speed of 35 mph. AISC Specification or ACI 318 plus the following provisions when surge load is combined with wind loads (4):

t Ulitmate Stress Design (AISC). The basic allowable stresses may be increased 50%, but not above the yield point of the material.

t Ultimate Strength Design (ACI). All load factors may be multiplied by 0.75, but net load factors shall not be reduced below 1.0.

t Load and Resistance Factor Design (AISC). Use a load factor of 1.15 on all loads.

NOTES:

TABLE 8

UNIFORMLY DISTRIBUTED PIPING DEAD LOADS FOR OPEN FRAME STRUCTURES

Estimated Piping Arrangement Uniform Dead Load (PSF)
Extensive piping is anticipated;
generally the lower two levels of tower structures		 20
Levels supporting a lesser amount of piping than above 10
Levels supporting possible future piping 0

TABLE 9

DESIGN FORCES FOR FLARE PIPING SYSTEMS

NPS (inch) Force (lbs)
4 1,500
6 3,000
8 5,000
10 8,000
12 12,000
14 14,000
16 20,000
18 24,000
20 and above 30,000

TABLE 10 COEFFICIENTS OF STATIC FRICTION

Surfaces Friction Coefficient
Teflon on Teflon 0.10(1)
Steel on Steel 0.40(2)
Steel on Concrete 0.45

NOTES:

(*)Slide plates (Teflon and other) are available with friction coefficients as low as 0.03. However, the value in the table shall be used unless slide plate designs warrant the use of a different value, in which case Owner's Engineer approval is required.

(*)The typical range for steel on steel is 0.2 to 0.6, depending on surface condition. "Clean mill scale" surface conditions produce a value of about 0.34. The value in the table shall be used unless surface conditions warrant the use of a different value, in which case Owner's Engineer approval is required.

TABLE 11

ASCE 7 WIND LOADING DESIGN PARAMETERS

Location Basic Design Wind Speed (mph) Exposure Category Importance Factor
Location ASCE 7- ASCE 7- ASCE 7-
Aruba 90.0 D(2) Tab 1-1 Tab6-1 ASCE 7

NOTE:

TABLE 12

ASCE 7 SEISMIC LOAD COEFFICIENTS

Location SS, Mapped Maximum Considered Earthquake, Short Period (5%
Damped) (1)		 S1, Mapped Maximum Considered Earthquake, 1 second-Period (5% Damped) (1) Soil Profile (Site Class) (2))
Location ASCE 7-98 ASCE 7-98 ASCE 7-98
In-Land (On Coral) 5.0 2.0 C
Coastline
(On Fill)		 5.0 2.0 E

NOTES:

TABLE 13 DOCUMENTATION REQUIREMENTS

FOR DESIGN CRITERIA AND LOADS FOR STRUCTURES PER EP 4-1-1

Item Description Format As-Built
1 Manufacturer's documentation of dead loads, impact loads and vibrations. Text N/A

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