D | = | Dead load. |
Di | = | Weight of ice in accordance with Chapter 10 of ASCE 7. |
E | = | Combined effect of horizontal and vertical earthquake induced forces as defined in Section 12.4.2 of ASCE 7. |
F | = | Load due to fluids with well-defined pressures and maximum heights. |
Fa | = | Flood load in accordance with Chapter 5 of ASCE 7. |
H | = | Load due to lateral earth pressures, ground water pressure or pressure of bulk materials. |
L | = | Roof live load greater than 20 psf (0.96 kN/m2) and floor live load. |
Lr | = | Roof live load of 20 psf (0.96 kN/m2) or less. |
R | = | Rain load. |
S | = | Snow load. |
T | = | Self-straining load. |
Vasd | = | Nominal design wind speed (3-second gust), miles per hour (mph) (km/hr) where applicable. |
Vult | = | Ultimate design wind speeds (3-second gust), miles per hour (mph) (km/hr) determined from Figures 1609A, 1609B, or 1609C or ASCE 7. |
W | = | Load due to wind pressure. |
Wi | = | Wind-on-ice in accordance with Chapter 10 of ASCE 7. |
- Floor and roof live loads.
- Ground snow load, Pg.
- Ultimate design wind speed, Vult, (3-second gust), miles per hour (mph) (km/hr) and nominal design wind speed, Vasd, as determined in accordance with Section 1609.3.1 and wind exposure.
- Seismic design category and site class.
- Flood design data, if located in flood hazard areas established in Section 1612.3.
- Design load-bearing values of soils.
- Ultimate design wind speed, Vult, (3-second gust), miles per hour (km/hr) and nominal design wind speed, Vasd, as determined in accordance with Section 1609.3.1.
- Risk category.
- Wind exposure. Applicable wind direction if more than one wind exposure is utilized.
- Applicable internal pressure coefficient.
- Design wind pressures to be used for exterior component and cladding materials not specifically designed by the registered design professional responsible for the design of the structure, psf (kN/m2).
Loads and forces for occupancies or uses not covered in this chapter shall be subject to the approval of the building official.
TABLE 1604.3
DEFLECTION LIMITSa, b, c, h, i
CONSTRUCTION | L | S or W f | D + Ld, g |
Roof members:e Supporting plaster or stucco ceiling Supporting nonplaster ceiling Not supporting ceiling | l/360 l/240 l/180 | l/360 l/240 l/180 | l/240 l/180 l/120 |
Floor members | l/360 | — | l/240 |
Exterior walls and interior partitions: With plaster or stucco finishes With other brittle finishes With flexible finishes | — — — | l/360 l/240 l/120 | — — — |
Farm buildings | — | — | l/180 |
Greenhouses | — | — | l /120 |
Members that tend to accumulate residual deformations under repeated service loads shall have included in their analysis the added eccentricities expected to occur during their service life.
Any system or method of construction to be used shall be based on a rational analysis in accordance with well-established principles of mechanics. Such analysis shall result in a system that provides a complete load path capable of transferring loads from their point of origin to the load-resisting elements.
The total lateral force shall be distributed to the various vertical elements of the lateral force-resisting system in proportion to their rigidities, considering the rigidity of the horizontal bracing system or diaphragm. Rigid elements assumed not to be a part of the lateral force-resisting system are permitted to be incorporated into buildings provided their effect on the action of the system is considered and provided for in the design. Except where diaphragms are flexible, or are permitted to be analyzed as flexible, provisions shall be made for the increased forces induced on resisting elements of the structural system resulting from torsion due to eccentricity between the center of application of the lateral forces and the center of rigidity of the lateral force-resisting system.
Every structure shall be designed to resist the overturning effects caused by the lateral forces specified in this chapter. See Section 1609 for wind loads, Section 1610 for lateral soil loads and Section 1613 for earthquake loads.
TABLE 1604.5
RISK CATEGORY OF BUILDINGS AND OTHER STRUCTURES
RISK CATEGORY | NATURE OF OCCUPANCY |
I | Buildings and other structures that represent a low hazard to human life in the event of failure, including but not limited to: • Agricultural facilities. • Certain temporary facilities. • Minor storage facilities. |
II | Buildings and other structures except those listed in Risk Categories I, III and IV |
III | Buildings and other structures that represent a substantial hazard to human life in the event of failure, including but not limited to: • Buildings and other structures whose primary occupancy is public assembly with an occupant load greater than 300. • Buildings and other structures containing elementary school, secondary school or day care facilities with an occupant load greater than 250. • Buildings and other structures containing adult education facilities, such as colleges and universities, with an occupant load greater than 500. • Group I-2 occupancies with an occupant load of 50 or more resident care recipients but not having surgery or emergency treatment facilities. • Group I-3 occupancies. • Any other occupancy with an occupant load greater than 5,000a. • Power-generating stations, water treatment facilities for potable water, waste water treatment facilities and other public utility facilities not included in Risk Category IV. • Buildings and other structures not included in Risk Category IV containing quantities of toxic or explosive materials that: Exceed maximum allowable quantities per control area as given in Table 307.1(1) or 307.1(2) or per outdoor control area in accordance with the International Fire Code; and Are sufficient to pose a threat to the public if released b. |
IV | Buildings and other structures designated as essential facilities, including but not limited to: • Group I-2 occupancies having surgery or emergency treatment facilities. • Fire, rescue, ambulance and police stations and emergency vehicle garages. • Designated earthquake, hurricane or other emergency shelters. • Designated emergency preparedness, communications and operations centers and other facilities required for emergency response. • Power-generating stations and other public utility facilities required as emergency backup facilities for Risk Category IV structures. • Buildings and other structures containing quantities of highly toxic materials that: Exceed maximum allowable quantities per control area as given in Table 307.1(2) or per outdoor control area in accordance with the International Fire Code; and Are sufficient to pose a threat to the public if released b. • Aviation control towers, air traffic control centers and emergency aircraft hangars. • Buildings and other structures having critical national defense functions. • Water storage facilities and pump structures required to maintain water pressure for fire suppression. |
Applicable loads shall be considered, including both earthquake and wind, in accordance with the specified load combinations. Each load combination shall also be investigated with one or more of the variable loads set to zero.
Where the load combinations with overstrength factor in Section 12.4.3.2 of ASCE 7 apply, they shall be used as follows:
1.4(D +F) | (Equation 16-1) |
1.2(D + F) + 1.6(L + H) + 0.5(Lr or S or R) | (Equation 16-2) |
1.2(D + F) + 1.6(Lr or S or R) + 1.6H + (f1L or 0.5W) | (Equation 16-3) |
1.2(D + F) + 1.0W + f1L + 1.6H + 0.5(Lr or S or R) | (Equation 16-4) |
1.2(D + F) + 1.0E + f1L + 1.6H + f2S | (Equation 16-5) |
0.9D+ 1.0W+ 1.6H | (Equation 16-6) |
0.9(D + F) + 1.0E+ 1.6H | (Equation 16-7) |
where:
f1 | = | 1 for places of public assembly live loads in excess of 100 pounds per square foot (4.79 kN/m2), and parking garages; and 0.5 for other live loads. |
f2 | = | 0.7 for roof configurations (such as saw tooth) that do not shed snow off the structure, and 0.2 for other roof configurations. |
D + F | (Equation 16-8) |
D + H + F + L | (Equation 16-9) |
D + H + F + (Lr or S or R) | (Equation 16-10) |
D + H + F+ 0.75(L) + 0.75(Lr or S or R) | (Equation 16-11) |
D + H + F + (0.6W or 0.7E) | (Equation 16-12) |
D + H + F + 0.75(0.6W) + 0.75L + 0.75(Lr or S or R) | (Equation 16-13) |
D + H + F + 0.75 (0.7 E) + 0.75 L + 0.75 S | (Equation 16-14) |
0.6D + 0.6W+H | (Equation 16-15) |
0.6(D + F) + 0.7E+H | (Equation 16-16) |
D + L + (Lr or S or R) | (Equation 16-17) |
D + L + 0.6 ωW | (Equation 16-18) |
D + L + 0.6 ωW + S/2 | (Equation 16-19) |
D + L + S + 0.6 ωW/2 | (Equation 16-20) |
D + L + S + E/1.4 | (Equation 16-21) |
0.9D + E/1.4 | (Equation 16-22) |
Exceptions:
Relocated
TABLE 1607.1
MINIMUM UNIFORMLY DISTRIBUTED LIVE LOADS, Lo, AND MINIMUM CONCENTRATED LIVE LOADSg
OCCUPANCY OR USE | UNIFORM (psf) | CONCENTRATED (lbs.) |
1. Apartments (see residential) | — | — |
2. Access floor systems | ||
Office use | 50 | 2,000 |
Computer use | 100 | 2,000 |
3. Armories and drill rooms | 150m | — |
4. Assembly areas | ||
Fixed seats (fastened to floor) | 60m | |
Follow spot, projections and control rooms | 50 | |
Lobbies | 100m | — |
Movable seats | 100m | |
Stage floors | 150m | |
Platforms (assembly) | 100m | |
Other assembly areas | 100m | |
5. Balconies and decksh | Same as occupancy served | — |
Deleted | ||
6. Catwalks | 40 | 300 |
7. Cornices | 60 | — |
8. Corridors | ||
First floor | 100 | |
Other floors | Same as occupancy served except as indicated | — |
Deleted | ||
9. Dining rooms and restaurants | 100m | — |
10. Dwellings (see residential) | — | — |
11. Elevator machine room grating (on area of 2 inches by 2 inches) | — | 300 |
12. Finish light floor plate construction (on area of 1 inch by 1 inch) | — | 200 |
13. Fire escapes On single-family dwellings only | 100 40 | — |
14. Garages (passenger vehicles only) Trucks and buses | 40m | Note a |
See Section1607.7 | ||
Deleted | ||
15. Handrails, guards and grab bars | See Section 1607.8 | |
16. Helipads | See Section1607.6 | |
17. Hospitals | ||
Corridors above first floor | 80 | 1,000 |
Operating rooms, laboratories | 60 | 1,000 |
Patient rooms | 40 | 1,000 |
18. Hotels (see residential) | — | — |
19. Libraries | ||
Corridors above first floor | 80 | 1,000 |
Reading rooms | 60 | 1,000 |
Stack rooms | 150b, m | 1,000 |
20. Manufacturing | ||
Heavy | 250m | 3,000 |
Light | 125m | 2,000 |
21. Marquees | 75 | — |
22. Office buildings | ||
Corridors above first floor | 80 | 2,000 |
File and computer rooms shall be designed for heavier loads based on anticipated occupancy | — | — |
Lobbies and first-floor corridors | 100 | 2,000 |
Offices | 50 | 2,000 |
(continued)
TABLE 1607.1—continued
MINIMUM UNIFORMLY DISTRIBUTED LIVE LOADS, Lo, AND MINIMUM CONCENTRATED LIVE LOADSg
OCCUPANCY OR USE | UNIFORM (psf) | CONCENTRATED (lbs.) |
23. Penal institutions | ||
Cell blocks | 40 | — |
Corridors | 100 | |
24. Recreational uses: | ||
Bowling alleys, poolrooms and similar uses | 75m | |
Dance halls and ballrooms | 100m | |
Gymnasiums | 100m | — |
Reviewing stands, grandstands and bleachers | 100c, m | |
Stadiums and arenas with fixed seats (fastened to floor) | 60c, m | |
25. Residential | ||
One- and two-family dwellings | ||
Uninhabitable attics without storagei | 10 | |
Uninhabitable attics with storage i, j, k | 20 | — |
Habitable attics and sleeping areask | 30 | |
All other areas | 40 | |
Hotels and multifamily dwellings | ||
Private rooms and corridors serving them | 40 | |
Public roomsm and corridors serving them | 100 | |
Deleted | ||
26. Roofs | ||
All roof surfaces subject to maintenance workers | 300 | |
Awnings and canopies: | ||
Fabric construction supported by a skeleton structure | 5 nonreducible | |
All other construction | 20 | |
Ordinary flat, pitched, and curved roofs (that are not occupiable) | 20 | |
Primary roof members are exposed to a work floor. | ||
Single panel point of lower chord of roof trusses or any point along primary structural members supporting roofs over manufacturing, storage warehouses, and repair garages | 2,000 | |
All other primary roof members | 300 | |
Occupiable roofs: | ||
Roof gardens | 100 | |
Assembly areas | 100m | |
All other similar areas | Note 1 | Note 1 |
27. Schools | ||
Classrooms | 40 | 1,000 |
Corridors above first floor | 80 | 1,000 |
First-floor corridors | 100 | 1,000 |
28. Scuttles, skylight ribs and accessible ceilings | — | 200 |
29. Sidewalks, vehicular drive ways and yards, subject to trucking | 250d, m | 8,000e |
(continued)
TABLE 1607.1—continued
MINIMUM UNIFORMLY DISTRIBUTED LIVE LOADS, Lo, AND MINIMUM CONCENTRATED LIVE LOADSg
OCCUPANCY OR USE | UNIFORM (psf) | CONCENTRATED (lbs.) |
Deleted | ||
30. Stairs and exits | ||
One- and two-family dwellings | 40 | 300f |
All other | 100 | 300f |
31. Storage warehouses (shall be designed for heavier loads if required for anticipated storage) | ||
Heavy | 250m | — |
Light | 125m | |
32. Stores | ||
Retail | ||
First floor | 100 | 1,000 |
Upper floors | 75 | 1,000 |
Wholesale, all floors | 125m | 1,000 |
33. Vehicle barriers | See Section 1607.8.3 | |
34. Walkways and elevated platforms (other than exitways) | 60 | — |
35. Yards and terraces, pedestrians | 100m | — |
Relocated
Landing areas designed for a design basis helicopter with maximum take-off weight of 3,000 pounds (13.35 kN) shall be identified with a 3,000 pound (13.34 kN) weight limitation. The landing area weight limitation shall be indicated by the numeral “3” (kips) located in the bottom right corner of the landing area as viewed from the primary approach path. The indication for the landing area weight limitation shall be a minimum 5 feet (1524 mm) in height.
Exception: The vehicular live loads and load placement are allowed to be determined using the actual vehicle weights for the vehicles allowed onto the garage floors, provided such loads and placement are based on rational engineering principles and are approved by the building official, but shall not be less than 50 psf (2.9 kN/m2). This live load shall not be reduced.
Exceptions:
(Equation 16-23) |
For SI: |
L | = | Reduced design live load per square foot (m2) of area supported by the member. |
Lo | = | Unreduced design live load per square foot (m2) of area supported by the member (see Table 1607.1). |
KLL | = | Live load element factor (see Table 1607.10.1). |
AT | = | Tributary area, in square feet (m2). |
TABLE 1607.10.1
LIVE LOAD ELEMENT FACTOR, KLL
ELEMENT | KLL |
Interior columns Exterior columns without cantilever slabs | 4 4 |
Edge columns with cantilever slabs | 3 |
Corner columns with cantilever slabs Edge beams without cantilever slabs Interior beams | 2 2 2 |
All other members not identified above including: Edge beams with cantilever slabs Cantilever beams One-way slabs Two-way slabs Members without provisions for continuous shear transfer normal to their span | 1 |
Exceptions:
Exception: The live loads for members supporting two or more floors are permitted to be reduced by a maximum of 20 percent, but the live load shall not be less than L as calculated in Section 1607.10.1.
Deleted
Deleted
Exception: For uses other than storage, where approved, additional live load reductions shall be permitted where shown by the registered design professional that a rational approach has been used and that such reductions are warranted.
R = 0.08(A – 150) | (Equation 16-24) |
For SI: R = 0.861(A – 13.94)
Such reduction shall not exceed the smallest of:
R = 23.1(1+ D/Lo) | (Equation 16-25) |
where:
A | = | Area of floor supported by the member, square feet (m2). |
D | = | Dead load per square foot (m2) of area supported. |
Lo | = | Unreduced live load per square foot (m2) of area supported. |
R | = | Reduction in percent. |
In structures such as greenhouses, where special scaffolding is used as a work surface for workers and materials during maintenance and repair operations, a lower roof load than specified in the following equations shall not be used unless approved by the building official. Such structures shall be designed for a minimum roof live load of 12 psf (0.58 kN/m2).
Lr = Lo R1R2 | (Equation 16-26) |
where: 12 ≤ Lr≤ 20
For SI: Lr = Lo R1R2
where: 0.58 ≤ Lr≤ 0.96
Lo | = | Unreduced roof live load per square foot (m2) of horizontal projection supported by the member (see Table 1607.1). |
Lr | = | Reduced roof live load per square foot (m2) of horizontal projection supported by the member. |
The reduction factors R1 and R2 shall be determined as follows:
R1 = 1 for At ≤ 200 square feet (18.58 m2) | (Equation 16-27) |
R1 = 1.2 - 0.001Atfor 200 square feet < At< 600 square feet | (Equation 16-28) |
For SI: 1.2 - 0.011Atfor 18.58 square meters < At< 55.74 square meters
R1 = 0.6 for At ≥ 600 square feet (55.74 m2) | (Equation 16-29) |
where:
At | = | Tributary area (span length multiplied by effective width) in square feet (m2) supported by the member, and |
R2= 1 for F ≤ 4 | (Equation 16-30) |
R2= 1.2 - 0.05 F for 4 < F < 12 | (Equation 16-31) |
R2= 0.6 for F ≥ 12 | (Equation 16-32) |
where:
F | = | For a sloped roof, the number of inches of rise per foot (for SI: F = 0.12 × slope, with slope expressed as a percentage), or for an arch or dome, the rise-to-span ratio multiplied by 32. |
Monorail cranes (powered) | 25 percent |
Cab-operated or remotely operated bridge cranes (powered) | 25 percent |
Pendant-operated bridge cranes (powered) | 10 percent |
Bridge cranes or monorail cranes with hand-geared bridge, trolley and hoist | 0 percent |
TABLE 1608.2
GROUND SNOW LOADS, pg , FOR ALASKAN LOCATIONS
LOCATION | POUNDS PER SQUARE FOOT | LOCATION | POUNDS PER SQUARE FOOT | LOCATION | POUNDS PER SQUARE FOOT | ||
Adak | 30 | Galena | 60 | Petersburg | 150 | ||
Anchorage | 50 | Gulkana | 70 | St. Paul Islands | 40 | ||
Angoon | 70 | Homer | 40 | Seward | 50 | ||
Barrow | 25 | Juneau | 60 | Shemya | 25 | ||
Barter Island | 35 | Kenai | 70 | Sitka | 50 | ||
Bethel | 40 | Kodiak | 30 | Talkeetna | 120 | ||
Big Delta | 50 | Kotzebue | 60 | Unalakleet | 50 | ||
Cold Bay | 25 | McGrath | 70 | Valdez | 160 | ||
Cordova | 100 | Nenana | 80 | Whittier | 300 | ||
Fairbanks | 60 | Nome | 70 | Wrangell | 60 | ||
Fort Yukon | 60 | Palmer | 50 | Yakutat | 150 |
FIGURE 1608.2
GROUND SNOW LOADS, pg, FOR THE UNITED STATES (psf)
FIGURE 1608.2—continued
GROUND SNOW LOADS, pg, FOR THE UNITED STATES (psf)
FIGURE 1609A
ULTIMATE DESIGN WIND SPEEDS, VULT, FOR RISK CATEGORY II BUILDINGS AND OTHER STRUCTURES
FIGURE 1609B
ULTIMATE DESIGN WIND SPEEDS, VULT, FOR RISK CATEGORY III AND IV BUILDINGS AND OTHER STRUCTURES
FIGURE 1609C
ULTIMATE DESIGN WIND SPEEDS, VULT, FOR RISK CATEGORY I BUILDINGS AND OTHER STRUCTURES
- Subject to the limitations of Section 1609.1.1.1, the provisions of ICC 600 shall be permitted for applicable Group R-2 and R-3 buildings.
- Subject to the limitations of Section 1609.1.1.1, residential structures using the provisions of AF&PA WFCM.
- Subject to the limitations of Section 1609.1.1.1, residential structures using the provisions of AISI S230.
- Designs using NAAMM FP 1001.
- Designs using TIA-222 for antenna-supporting structures and antennas, provided the horizontal extent of Topographic Category 2 escarpments in Section 2.6.6.2 of TIA-222 shall be 16 times the height of the escarpment.
- Wind tunnel tests in accordance with Chapter 31 of ASCE 7.
- The hill, ridge or escarpment is 60 feet (18 288 mm) or higher if located in Exposure B or 30 feet (9144 mm) or higher if located in Exposure C;
- The maximum average slope of the hill exceeds 10 percent; and
- The hill, ridge or escarpment is unobstructed upwind by other such topographic features for a distance from the high point of 50 times the height of the hill or 1 mile (1.61 km), whichever is greater.
Deleted
- Glazed openings located within 30 feet (9144 mm) of grade shall meet the requirements of the large missile test of ASTM E 1996.
- Glazed openings located more than 30 feet (9144 mm) above grade shall meet the provisions of the small missile test of ASTM E 1996.
Exceptions:
- Wood structural panels with a minimum thickness of 7/16 inch (11.1 mm) and maximum panel span of 8 feet (2438 mm) shall be permitted for opening protection in one- and two-story buildings classified as Group R-3 or R-4 occupancy. Panels shall be precut so that they shall be attached to the framing surrounding the opening containing the product with the glazed opening. Panels shall be predrilled as required for the anchorage method and shall be secured with the attachment hardware provided. Attachments shall be designed to resist the components and cladding loads determined in accordance with the provisions of ASCE 7, with corrosion-resistant attachment hardware provided and anchors permanently installed on the building. Attachment in accordance with Table 1609.1.2 with corrosion-resistant attachment hardware provided and anchors permanently installed on the building is permitted for buildings with a mean roof height of 45 feet (13 716 mm) or less where Vasd determined in accordance with Section 1609.3.1 does not exceed 140 mph (63 m/s).
- Glazing in Risk Category I buildings as defined in Section 1604.5, including greenhouses that are occupied for growing plants on a production or research basis, without public access shall be permitted to be unprotected.
- Glazing in Risk Category II, III or IV buildings located over 60 feet (18 288 mm) above the ground and over 30 feet (9144 mm) above aggregate surface roofs located within 1,500 feet (458 m) of the building shall be permitted to be unprotected.
TABLE 1609.1.2
WIND-BORNE DEBRIS PROTECTION FASTENING SCHEDULE FOR WOOD STRUCTURAL PANELSa, b, c, d
FASTENER TYPE | FASTENER SPACING (inches) | ||
Panel Span ≤ 4 feet | 4 feet < Panel Span ≤ 6 feet | 6 feet < Panel Span ≤ 8 feet | |
No. 8 wood-screw- based anchor with 2 -inch embedment length | 16 | 10 | 8 |
No. 10 wood-screw -based anchor with 2-inch embedment length | 16 | 12 | 9 |
1/4-inch diameter lag-screw-based anchor with 2-inch embedment length | 16 | 16 | 16 |
- This table is based on 140 mph wind speeds and a 45-foot mean roof height.
- Fasteners shall be installed at opposing ends of the wood structural panel. Fasteners shall be located a minimum of 1 inch from the edge of the panel.
- Anchors shall penetrate through the exterior wall covering with an embedment length of 2 inches minimum into the building frame. Fasteners shall be located a minimum of 21/2 inches from the edge of concrete block or concrete.
- Where panels are attached to masonry or masonry/stucco, they shall be attached using vibration-resistant anchors having a minimum ultimate withdrawal capacity of 1,500 pounds.
6.2.2 Unless otherwise specified, select the wind zone based on the strength design wind speed, Vult, as follows:
6.2.2.1 Wind Zone 1—130 mph ≤ ultimate design wind speed, Vult< 140 mph.
6.2.2.2 Wind Zone 2—140 mph ≤ ultimate design wind speed, Vult< 150 mph at greater than one mile (1.6 km) from the coastline. The coastline shall be measured from the mean high water mark.
6.2.2.3 Wind Zone 3—150 mph (58 m/s) ≤ ultimate design wind speed, Vult ≤ 160 mph (63 m/s), or 140 mph (54 m/s) ≤ ultimate design wind speed, Vult ≤ 160 mph (63 m/s) and within one mile(1.6 km) of the coastline. The coastline shall be measured from the mean high water mark.
6.2.2.4 Wind Zone 4— ultimate design wind speed, Vult >160 mph (63 m/s).
In nonhurricane-prone regions, when the ultimate design wind speed, Vult, is estimated from regional climatic data, the ultimate design wind speed, Vult, shall be determined in accordance with Section 26.5.3 of ASCE 7.
(Equation 16-33) |
Vasd | = | nominal design wind speed applicable to methods specified in Exceptions 1 through 5 of Section 1609.1.1. |
Vult | = | ultimate design wind speeds determined from Figures 1609A, 1609B or 1609C. |
TABLE 1609.3.1
WIND SPEED CONVERSIONSa, b, c
Vult | 100 | 110 | 120 | 130 | 140 | 150 | 160 | 170 | 180 | 190 | 200 |
Vasd | 78 | 85 | 93 | 101 | 108 | 116 | 124 | 132 | 139 | 147 | 155 |
Urban and suburban areas, wooded areas or other terrain with numerous closely spaced obstructions having the size of single-family dwellings or larger.
Open terrain with scattered obstructions having heights generally less than 30 feet (9144 mm). This category includes flat open country, and grasslands.
Flat, unobstructed areas and water surfaces. This category includes smooth mud flats, salt flats and unbroken ice.
Deleted
Exception: Rigid tile roof coverings that are air permeable and installed over a roof deck complying with Section 1609.5.1 are permitted to be designed in accordance with Section 1609.5.3.
Asphalt shingles installed over a roof deck complying with Section 1609.5.1 shall comply with the wind-resistance requirements of Section 1507.2.7.1.
Ma= qhCLbLLa[1.0 - GCp] | (Equation 16-34) |
For SI: Ma | = |
b | = | Exposed width, feet (mm) of the roof tile. |
CL | = | Lift coefficient. The lift coefficient for concrete and clay tile shall be 0.2 or shall be determined by test in accordance with Section 1711.2. |
GCp | = | Roof pressure coefficient for each applicable roof zone determined from Chapter 30 of ASCE 7. Roof coefficients shall not be adjusted for internal pressure. |
L | = | Length, feet (mm) of the roof tile. |
La | = | Moment arm, feet (mm) from the axis of rotation to the point of uplift on the roof tile. The point of uplift shall be taken at 0.76L from the head of the tile and the middle of the exposed width. For roof tiles with nails or screws (with or without a tail clip), the axis of rotation shall be taken as the head of the tile for direct deck application or as the top edge of the batten for battened applications. For roof tiles fastened only by a nail or screw along the side of the tile, the axis of rotation shall be determined by testing. For roof tiles installed with battens and fastened only by a clip near the tail of the tile, the moment arm shall be determined about the top edge of the batten with consideration given for the point of rotation of the tiles based on straight bond or broken bond and the tile profile. |
Ma | = | Aerodynamic uplift moment, feet-pounds (N-mm) acting to raise the tail of the tile. |
qh | = | Wind velocity pressure, psf (kN/m2) determined from Section 27.3.2 of ASCE 7. |
Cnet | = | Net-pressure coefficient based on Kd [(G) (Cp) - (GCp i)], in accordance with Table 1609.6.2. |
G | = | Gust effect factor for rigid structures in accordance with ASCE 7 Section 26.9.1. |
Kd | = | Wind directionality factor in accordance with ASCE 7 Table 26-6. |
Pnet | = | Design wind pressure to be used in determination of wind loads on buildings or other structures or their components and cladding, in psf (kN/m2). |
TABLE 1609.6.2
NET PRESSURE COEFFICIENTS, Cneta, b
STRUCTURE OR PART THEREOF | DESCRIPTION | Cnet FACTOR | ||||||
1. Main windforce-resisting frames and systems | Walls: | Enclosed | Partially enclosed | |||||
+ Internal pressure | - Internal pressure | + Internal pressure | - Internal pressure | |||||
Windward wall | 0.43 | 0.73 | 0.11 | 1.05 | ||||
Leeward wall | -0.51 | -0.21 | -0.83 | 0.11 | ||||
Sidewall | -0.66 | -0.35 | -0.97 | -0.04 | ||||
Parapet wall | Windward | 1.28 | 1.28 | |||||
Leeward | -0.85 | -0.85 | ||||||
Roofs: | Enclosed | Partially enclosed | ||||||
Wind perpendicular to ridge | + Internal pressure | - Internal pressure | + Internal pressure | - Internal pressure | ||||
Leeward roof or flat roof | -0.66 | -0.35 | -0.97 | -0.04 | ||||
Windward roof slopes: | ||||||||
Slope < 2:12 (10°) | Condition 1 | -1.09 | -0.79 | -1.41 | -0.47 | |||
Condition 2 | -0.28 | 0.02 | -0.60 | 0.34 | ||||
Slope = 4:12 (18°) | Condition 1 | -0.73 | -0.42 | -1.04 | -0.11 | |||
Condition 2 | -0.05 | 0.25 | -0.37 | 0.57 | ||||
Slope = 5:12 (23°) | Condition 1 | -0.58 | -0.28 | -0.90 | 0.04 | |||
Condition 2 | 0.03 | 0.34 | -0.29 | 0.65 | ||||
Slope = 6:12 (27°) | Condition 1 | -0.47 | -0.16 | -0.78 | 0.15 | |||
Condition 2 | 0.06 | 0.37 | -0.25 | 0.68 | ||||
Slope = 7:12 (30°) | Condition 1 | -0.37 | -0.06 | -0.68 | 0.25 | |||
Condition 2 | 0.07 | 0.37 | -0.25 | 0.69 | ||||
Slope = 9:12 (37°) | Condition 1 | -0.27 | 0.04 | -0.58 | 0.35 | |||
Condition 2 | 0.14 | 0.44 | -0.18 | 0.76 | ||||
Slope = 12:12 (45°) | 0.14 | 0.44 | -0.18 | 0.76 | ||||
Wind parallel to ridge and flat roofs | -1.09 | -0.79 | -1.41 | -0.47 | ||||
Nonbuilding Structures: Chimneys, Tanks and Similar Structures: | ||||||||
h/D | ||||||||
1 | 7 | 25 | ||||||
Square (Wind normal to face) | 0.99 | 1.07 | 1.53 | |||||
Square (Wind on diagonal) | 0.77 | 0.84 | 1.15 | |||||
Hexagonal or Octagonal | 0.81 | 0.97 | 1.13 | |||||
Round | 0.65 | 0.81 | 0.97 | |||||
Open signs and lattice frameworks | Ratio of solid to gross area | |||||||
< 0.1 | 0.1 to 0.29 | 0.3 to 0.7 | ||||||
Flat | 1.45 | 1.30 | 1.16 | |||||
Round | 0.87 | 0.94 | 1.08 |
(continued)
TABLE 1609.6.2—continued
NET PRESSURE COEFFICIENTS, Cneta, b
STRUCTURE OR PART THEREOF | DESCRIPTION | Cnet FACTOR | ||
2. Components and cladding not in areas of discontinuity— roofs and overhangs | Roof elements and slopes | Enclosed | Partially enclosed | |
Gable of hipped configurations (Zone 1) | ||||
Flat < Slope < 6:12 (27°) See ASCE 7 Figure 30.4-2B Zone 1 | ||||
Positive | 10 square feet or less | 0.58 | 0.89 | |
100 square feet or more | 0.41 | 0.72 | ||
Negative | 10 square feet or less | -1.00 | -1.32 | |
100 square feet or more | -0.92 | -1.23 | ||
Overhang: Flat < Slope < 6:12 (27°) See ASCE 7 Figure 30.4-2A Zone 1 | ||||
Negative | 10 square feet or less | -1.45 | ||
100 square feet or more | -1.36 | |||
500 square feet or more | -0.94 | |||
6:12 (27°) < Slope < 12:12 (45°) See ASCE 7 Figure 30.4-2C Zone 1 | ||||
Positive | 10 square feet or less | 0.92 | 1.23 | |
100 square feet or more | 0.83 | 1.15 | ||
Negative | 10 square feet or less | -1.00 | -1.32 | |
100 square feet or more | -0.83 | -1.15 | ||
Monosloped configurations (Zone 1) | Enclosed | Partially enclosed | ||
Flat < Slope < 7:12 (30°) See ASCE 7 Figure 30.4-5B Zone 1 | ||||
Positive | 10 square feet or less | 0.49 | 0.81 | |
100 square feet or more | 0.41 | 0.72 | ||
Negative | 10 square feet or less | -1.26 | -1.57 | |
100 square feet or more | -1.09 | -1.40 | ||
Tall flat-topped roofs h > 60 feet | Enclosed | Partially enclosed | ||
Flat < Slope < 2:12 (10°) (Zone 1) See ASCE 7 Figure 30.8-1 Zone 1 | ||||
Negative | 10 square feet or less | -1.34 | -1.66 | |
500 square feet or more | -0.92 | -1.23 | ||
3. Components and cladding in areas of discontinuities— roofs and overhangs (continued) | Gable or hipped configurations at ridges, eaves and rakes (Zone 2) | |||
Flat < Slope < 6:12 (27°) See ASCE 7 Figure 30.4-2B Zone 2 | ||||
Positive | 10 square feet or less | 0.58 | 0.89 | |
100 square feet or more | 0.41 | 0.72 | ||
Negative | 10 square feet or less | -1.68 | -2.00 | |
100 square feet or more | -1.17 | -1.49 | ||
Overhang for Slope Flat < Slope < 6:12 (27°) See ASCE 7 Figure 30.4-2B Zone 2 | ||||
Negative | 10 square feet or less | -1.87 | ||
100 square feet or more | -1.87 | |||
6:12 (27°) < Slope < 12:12 (45°) Figure 30.4-2C | Enclosed | Partially enclosed | ||
Positive | 10 square feet or less | 0.92 | 1.23 | |
100 square feet or more | 0.83 | 1.15 | ||
Negative | 10 square feet or less | -1.17 | -1.49 | |
100 square feet or more | -1.00 | -1.32 | ||
Overhang for 6:12 (27°) < Slope < 12:12 (45°) See ASCE 7 Figure 30.4-2C Zone 2 | ||||
Negative | 10 square feet or less | -1.70 | ||
500 square feet or more | -1.53 |
(continued)
TABLE 1609.6.2—continued
NET PRESSURE COEFFICIENTS, Cneta, b
STRUCTURE OR PART THEREOF | DESCRIPTION | Cnet FACTOR | ||
3. Components and cladding in areas of discontinuities —roofs and overhangs | Roof elements and slopes | Enclosed | Partially enclosed | |
Monosloped configurations at ridges, eaves and rakes (Zone 2) | ||||
Flat < Slope < 7:12 (30°) See ASCE 7 Figure 30.4-5B Zone 2 | ||||
Positive | 10 square feet or less | 0.49 | 0.81 | |
100 square feet or more | 0.41 | 0.72 | ||
Negative | 10 square feet or less | -1.51 | -1.83 | |
100 square feet or more | -1.43 | -1.74 | ||
Tall flat topped roofs h > 60 feet | Enclosed | Partially enclosed | ||
Flat < Slope < 2:12 (10°) (Zone 2) See ASCE 7 Figure 30.8-1 Zone 2 | ||||
Negative | 10 square feet or less | -2.11 | -2.42 | |
500 square feet or more | -1.51 | -1.83 | ||
Gable or hipped configurations at corners (Zone 3) See ASCE 7 Figure 30.4-2B Zone 3 | ||||
Flat < Slope < 6:12 (27°) | Enclosed | Partially enclosed | ||
Positive | 10 square feet or less | 0.58 | 0.89 | |
100 square feet or more | 0.41 | 0.72 | ||
Negative | 10 square feet or less | -2.53 | -2.85 | |
100 square feet or more | -1.85 | -2.17 | ||
Overhang for Slope Flat < Slope < 6:12 (27°) See ASCE 7 Figure 30.4-2B Zone 3 | ||||
Negative | 10 square feet or less | -3.15 | ||
100 square feet or more | -2.13 | |||
6:12 (27°) < 12:12 (45°) See ASCE 7 Figure 30.4-2C Zone 3 | ||||
Positive | 10 square feet or less | 0.92 | 1.23 | |
100 square feet or more | 0.83 | 1.15 | ||
Negative | 10 square feet or less | -1.17 | -1.49 | |
100 square feet or more | -1.00 | -1.32 | ||
Overhang for 6:12 (27°) < Slope < 12:12 (45°) | Enclosed | Partially enclosed | ||
Negative | 10 square feet or less | -1.70 | ||
100 square feet or more | -1.53 | |||
Monosloped Configurations at corners (Zone 3) See ASCE 7 Figure 30.4-5B Zone 3 | ||||
Flat < Slope < 7:12 (30°) | ||||
Positive | 10 square feet or less | 0.49 | 0.81 | |
100 square feet or more | 0.41 | 0.72 | ||
Negative | 10 square feet or less | -2.62 | -2.93 | |
100 square feet or more | -1.85 | -2.17 | ||
Tall flat topped roofs h > 60 feet | Enclosed | Partially enclosed | ||
Flat < Slope < 2:12 (10°) (Zone 3) See ASCE 7 Figure 30.8-1 Zone 3 | ||||
Negative | 10 square feet or less | -2.87 | -3.19 | |
500 square feet or more | -2.11 | -2.42 | ||
4. Components and cladding not in areas of discontinuity —walls and parapets (continued) | Wall Elements: h ≤ 60 feet (Zone 4) ASCE 7 Figure 30.4-1 | Enclosed | Partially enclosed | |
Positive | 10 square feet or less | 1.00 | 1.32 | |
500 square feet or more | 0.75 | 1.06 | ||
Negative | 10 square feet or less | -1.09 | -1.40 | |
500 square feet or more | -0.83 | -1.15 | ||
Wall Elements: h > 60 feet (Zone 4) ASCE 7 Figure 30.6-1 | ||||
Positive | 20 square feet or less | 0.92 | 1.23 | |
500 square feet or more | 0.66 | 0.98 |
(continued)
TABLE 1609.6.2—continued
NET PRESSURE COEFFICIENTS, Cneta, b
STRUCTURE OR PART THEREOF | DESCRIPTION | Cnet FACTOR | ||
4. Components and cladding not in areas of discontinuity -walls and parapets | Negative | 20 square feet or less | -0.92 | -1.23 |
500 square feet or more | -0.75 | -1.06 | ||
Parapet Walls | ||||
Positive | 2.87 | 3.19 | ||
Negative | -1.68 | -2.00 | ||
5. Components and cladding in areas of discontinuity—walls and parapets | Wall elements: h ≤ 60 feet (Zone 5) Figure 30.4-1 | Enclosed | Partially enclosed | |
Positive | 10 square feet or less | 1.00 | 1.32 | |
500 square feet or more | 0.75 | 1.06 | ||
Negative | 10 square feet or less | -1.34 | -1.66 | |
500 square feet or more | -0.83 | -1.15 | ||
Wall elements: h > 60 feet (Zone 4) ASCE 7 Figure 30.6-1 | ||||
Positive | 20 square feet or less | 0.92 | 1.23 | |
500 square feet or more | 0.66 | 0.98 | ||
Negative | 20 square feet or less | -1.68 | -2.00 | |
500 square feet or more | -1.00 | -1.32 | ||
Parapet walls | ||||
Positive | 3.64 | 3.95 | ||
Negative | -2.45 | -2.76 |
Deleted
Pnet= 0.00256V2KzCnetKzt | (Equation 16-35) |
- For the windward side of a structure, Kzt and Kz shall be based on height z.
- For leeward and sidewalls, and for windward and leeward roofs, Kzt and Kz shall be based on mean roof height h.
TABLE 1610.1
LATERAL SOIL LOAD
DESCRIPTION OF BACKFILL MATERIALc | UNIFIED SOIL CLASSIFICATION | DESIGN LATERAL SOIL LOADa (pound per square foot per foot of depth) | |
Active pressure | At-rest pressure | ||
Well-graded, clean gravels; gravel-sand mixes | GW | 30 | 60 |
Poorly graded clean gravels; gravel-sand mixes | GP | 30 | 60 |
Silty gravels, poorly graded gravel-sand mixes | GM | 40 | 60 |
Clayey gravels, poorly graded gravel-and-clay mixes | GC | 45 | 60 |
Well-graded, clean sands; gravelly sand mixes | SW | 30 | 60 |
Poorly graded clean sands; sand-gravel mixes | SP | 30 | 60 |
Silty sands, poorly graded sand-silt mixes | SM | 45 | 60 |
Sand-silt clay mix with plastic fines | SM-SC | 45 | 100 |
Clayey sands, poorly graded sand-clay mixes | SC | 60 | 100 |
Inorganic silts and clayey silts | ML | 45 | 100 |
Mixture of inorganic silt and clay | ML-CL | 60 | 100 |
Inorganic clays of low to medium plasticity | CL | 60 | 100 |
Organic silts and silt clays, low plasticity | OL | Note b | Note b |
Inorganic clayey silts, elastic silts | MH | Note b | Note b |
Inorganic clays of high plasticity | CH | Note b | Note b |
Organic clays and silty clays | OH | Note b | Note b |
R = 5.2(ds + dh) | (Equation 16-36) |
For SI: R = 0.0098(ds + dh)
where:
dh | = | Additional depth of water on the undeflected roof above the inlet of secondary drainage system at its design flow (i.e., the hydraulic head), in inches (mm). |
ds | = | Depth of water on the undeflected roof up to the inlet of secondary drainage system when the primary drainage system is blocked (i.e., the static head), in inches (mm). |
R | = | Rain load on the undeflected roof, in psf (kN/m2). When the phrase “undeflected roof” is used, deflections from loads (including dead loads) shall not be considered when determining the amount of rain on the roof. |
[P] FIGURE 1611.1
100-YEAR, 1-HOUR RAINFALL (INCHES) WESTERN UNITED STATES
[P] FIGURE 1611.1—continued
100-YEAR, 1-HOUR RAINFALL (INCHES) CENTRAL UNITED STATES
[P] FIGURE 1611.1—continued
100-YEAR, 1-HOUR RAINFALL (INCHES) EASTERN UNITED STATES
[P] FIGURE 1611.1—continued
100-YEAR, 1-HOUR RAINFALL (INCHES) ALASKA
[P] FIGURE 1611.1—continued
100-YEAR, 1-HOUR RAINFALL (INCHES) HAWAII
VELOCITY WAVE ACTION.
Deleted
Deleted
FIGURE 1613.3.1(1)
RISK-TARGETED MAXIMUM CONSIDERED EARTHQUAKE (MCER) GROUND MOTION RESPONSE ACCELERATIONS
FOR THE CONTERMINOUS UNITED STATES OF 0.2-SECOND SPECTRAL RESPONSE ACCELERATION
(5% OF CRITICAL DAMPING), SITE CLASS B
(continued)
FIGURE 1613.3.1(1)—continued
RISK-TARGETED MAXIMUM CONSIDERED EARTHQUAKE (MCER) GROUND MOTION RESPONSE ACCELERATIONS
FOR THE CONTERMINOUS UNITED STATES OF 0.2-SECOND SPECTRAL RESPONSE ACCELERATION
(5% OF CRITICAL DAMPING), SITE CLASS B
FIGURE 1613.3.1(2)
RISK-TARGETED MAXIMUM CONSIDERED EARTHQUAKE (MCER) GROUND MOTION RESPONSE ACCELERATIONS
FOR THE CONTERMINOUS UNITED STATES OF 1-SECOND SPECTRAL RESPONSE ACCELERATION
(5% OF CRITICAL DAMPING), SITE CLASS B
(continued)
FIGURE 1613.3.1(2)—continued
RISK-TARGETED MAXIMUM CONSIDERED EARTHQUAKE (MCER) GROUND MOTION RESPONSE ACCELERATIONS
FOR THE CONTERMINOUS UNITED STATES OF 1-SECOND SPECTRAL RESPONSE ACCELERATION
(5% OF CRITICAL DAMPING), SITE CLASS B
FIGURE 1613.3.1(3)
RISK-TARGETED MAXIMUM CONSIDERED EARTHQUAKE (MCER) GROUND MOTION RESPONSE ACCELERATIONS
FOR HAWAII OF 0.2- AND 1-SECOND SPECTRAL RESPONSE ACCELERATION
(5% OF CRITICAL DAMPING), SITE CLASS B
FIGURE 1613.3.1(4)
RISK-TARGETED MAXIMUM CONSIDERED EARTHQUAKE (MCER) GROUND MOTION RESPONSE ACCELERATIONS
FOR ALASKA OF 0.2-SECOND SPECTRAL RESPONSE ACCELERATION
(5% OF CRITICAL DAMPING), SITE CLASS B
FIGURE 1613.3.1(5)
RISK-TARGETED MAXIMUM CONSIDERED EARTHQUAKE (MCER) GROUND MOTION RESPONSE ACCELERATIONS
FOR ALASKA OF 1.0-SECOND SPECTRAL RESPONSE ACCELERATION
(5% OF CRITICAL DAMPING), SITE CLASS B
FIGURE 1613.3.1(6)
RISK-TARGETED MAXIMUM CONSIDERED EARTHQUAKE (MCER) GROUND MOTION RESPONSE ACCELERATIONS
FOR PUERTO RICO AND THE UNITED STATES VIRGIN ISLANDS OF 0.2- AND 1-SECOND SPECTRAL RESPONSE ACCELERATION (5% OF CRITICAL DAMPING), SITE CLASS B
Deleted
SMS = FaSs | (Equation 16-37) |
SM1= FvS1 | (Equation 16-38) |
Fa | = | Site coefficient defined in Table 1613.3.3(1). |
Fv | = | Site coefficient defined in Table 1613.3.3(2). |
SS | = | The mapped spectral accelerations for short periods as determined in Section 1613.3.1. |
S1 | = | The mapped spectral accelerations for a 1-second period as determined in Section 1613.3.1. |
TABLE 1613.3.3(1)
VALUES OF SITE COEFFICIENT Faa
SITE CLASS | MAPPED SPECTRAL RESPONSE ACCELERATION AT SHORT PERIOD | ||||
Ss ≤ 0.25 | Ss = 0.50 | Ss = 0.75 | Ss = 1.00 | Ss ≥ 1.25 | |
A | 0.8 | 0.8 | 0.8 | 0.8 | 0.8 |
B | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 |
C | 1.2 | 1.2 | 1.1 | 1.0 | 1.0 |
D | 1.6 | 1.4 | 1.2 | 1.1 | 1.0 |
E | 2.5 | 1.7 | 1.2 | 0.9 | 0.9 |
F | Note b | Note b | Note b | Note b | Note b |
TABLE 1613.3.3(2)
VALUES OF SITE COEFFICIENT FVa
SITE CLASS | MAPPED SPECTRAL RESPONSE ACCELERATION AT 1-SECOND PERIOD | ||||
S1 ≤ 0.1 | S1 = 0.2 | S1 = 0.3 | S1 = 0.4 | S1 ≥ 0.5 | |
A | 0.8 | 0.8 | 0.8 | 0.8 | 0.8 |
B | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 |
C | 1.7 | 1.6 | 1.5 | 1.4 | 1.3 |
D | 2.4 | 2.0 | 1.8 | 1.6 | 1.5 |
E | 3.5 | 3.2 | 2.8 | 2.4 | 2.4 |
F | Note b | Note b | Note b | Note b | Note b |
(Equation 16-39) |
(Equation 16-40) |
SMS | = | The maximum considered earthquake spectral response accelerations for short period as determined in Section 1613.3.3. |
SM1 | = | The maximum considered earthquake spectral response accelerations for 1-second period as determined in Section 1613.3.3. |
Deleted
TABLE 1613.3.5(1)
SEISMIC DESIGN CATEGORY BASED ON SHORT-PERIOD (0.2 second) RESPONSE ACCELERATION
VALUE OF SDS | RISK CATEGORY | ||
I or II | III | IV | |
SDS < 0.167g | A | A | A |
0.167g ≤ SDS < 0.33g | B | B | C |
0.33g ≤ SDS < 0.50g | C | C | D |
0.50g ≤ SDS | D | D | D |
TABLE 1613.3.5(2)
SEISMIC DESIGN CATEGORY BASED ON 1-SECOND PERIOD RESPONSE ACCELERATION
VALUE OF SD1 | RISK CATEGORY | ||
I or II | III | IV | |
SD1 < 0.067g | A | A | A |
0.067g ≤ SD1 < 0.133g | B | B | C |
0.133g ≤ SD1 < 0.20g | C | C | D |
0.20g ≤ SD1 | D | D | D |
Deleted
Exception: For isolated structures designed in accordance with this standard, the structural system limitations including structural height limits in Table 12.2-1 for ordinary steel concentrically braced frames (OCBFs) as defined in Chapter 11 and ordinary moment frames (OMFs) as defined in Chapter 11 are permitted to be taken as 160 feet (48 768 mm) for structures assigned to Seismic Design Category D, E or F, provided that the following conditions are satisfied:
Deleted
Exception: Where concrete slabs with continuous reinforcement having an area not less than 0.0015 times the concrete area in each of two orthogonal directions are present and are either monolithic with or equivalently bonded to beams, girders or columns, the longitudinal reinforcing or prestressing steel passing through the column reinforcement shall have a nominal tensile strength of one-third of the required one-way vertical strength of the connection of the floor or roof system to the column in each direction of beam or slab reinforcement passing through the column.
Exception: Where beams, girders, open web joist and joist girders support a concrete slab or concrete slab on metal deck that is attached to the beam or girder with not less than 3/8-inch-diameter (9.5 mm) headed shear studs, at a spacing of not more than 12 inches (305 mm) on center, averaged over the length of the member, or other attachment having equivalent shear strength, and the slab contains continuous distributed reinforcement in each of two orthogonal directions with an area not less than 0.0015 times the concrete area, the nominal axial tension strength of the end connection shall be permitted to be taken as half the required vertical shear strength for ASD or one-third of the required shear strength for LRFD, but not less than 10 kips (45 kN).
FIGURE 1615.4
LONGITUDINAL, PERIMETER, TRANSVERSE AND VERTICAL TIES
TT = w LS ≤ αTS | (Equation 16-41) |
where:
L | = | The span of the horizontal element in the direction of the tie, between bearing walls, feet (m). |
w | = | The weight per unit area of the floor or roof in the span being tied to or across the wall, psf (N/m2). |
S | = | The spacing between ties, feet (m). |
αT | = | A coefficient with a value of 1,500 pounds per foot (2.25 kN/m) for masonry bearing wall structures and a value of 375 pounds per foot (0.6 kN/m) for structures with bearing walls of cold-formed steel light-frame construction. |
Tp= 200w ≤βT | (Equation 16-42) |
For SI: Tp= 90.7w ≤βT
where:
w | = | As defined in Section 1615.4.2.1. |
βT | = | A coefficient with a value of 16,000 pounds (7200 kN) for structures with masonry bearing walls and a value of 4,000 pounds (1300 kN) for structures with bearing walls of cold-formed steel light-frame construction. |