NFPA 13 AMD 2-2015 Standard for the Installation of Sprinkler Systems (Effective Date 09 07 2015).pdf

1、 Page 1 of 20 Tentative Interim Amendment NFPA 13 Standard for the Installation of Sprinkler Systems 2016 Edition Reference: 2.3.1, 3.11.9, A.3.11.9, 9.3.5.12, A.9.3.5.12, A.9.3.5.12.1 and E.7 TIA 16-2 (SC 15-8-15 / TIA Log #1180) Note: Text of the TIA was issued and incorporated into the document p

2、rior to printing, therefore no separate publication is necessary. 1. Revise the reference in 2.3.1 to read as follows: 2.3.1 ACI Publications. American Concrete Institute, P.O. Box 9094, Farmington Hills, MI 48333. ACI 318-14, Building Code Requirements for Structural Concrete and Commentary, 2014.

3、ACI 355.2, Qualification of Post-Installed Mechanical Anchors in Concrete and Commentary, 2007. 2. Add a new definition on Prying Factor and corresponding annex to read as follows: 3.11.9* Prying Factor. A factor based on fitting geometry and brace angle from vertical that results in an increase in

4、tension load due to the effects of prying between the upper seismic brace attachment fitting and the structure. A. 3.11.9 Prying factors in NFPA 13 are utilized to determine the design loads for attachments to concrete. Prying is a particular concern for anchorage to concrete because the anchor may

5、fail in a brittle fashion. Page 2 of 20 3. Revise section 9.3.5.12 as follows: 9.3.5.12* Fasteners. 9.3.5.12.1 The designated angle category for the fastener(s) used in the sway brace installation shall be determined in accordance with Figure 9.3.5.12.1. Figure 9.3.5.12.1 Designation of Angle Catego

6、ry Based on Angle of Sway Brace and Fastener Orientation. 9.3.5.12.12* For individual fasteners, unless alternate allowable loads are determined and certified by a registered professional engineer, the loads determined in 9.3.5.9 shall not exceed the allowable loads provided in Tables 9.3.5.12.2(a)

7、through 9.3.5.12.2(i). Page 3 of 20 Table 9.3.5.12.2 (a) Maximum Load for Wedge Anchors in 3000 psi (207 bar) Lightweight Cracked Concrete on Metal Deck. Wedge Anchors in 3000 psi Lightweight Cracked Concrete on Metal Deck (lbs.) Diameter (in.) Embedment (in.) A B C D E F G H I Pr Pr Pr Pr Pr Pr Pr

8、Pr Pr Brace angle from vertical nullnull null nullnullCnullAnullnullnullnullnull nullDnull/A If Cr Brace angle from vertical nullnull null nullnullnullnullnullnullnullnullnullnull null nullnull/null If Cr Brace angle from vertical nullnull null nullnullDnullnullnullnullnull nullnullnullnullnullnulln

9、ull/B If Cr Brace angle from vertical nullnull null nullnullDnullnullnullnullnull nullnullnullnullnullnullnull/A If Cr Brace angle from vertical nullnull null nullnullCnullnullnull null nullDnullnullnullnullnullnull/B For designated angle category G, H and I the Applied Tension including the effect

10、of prying (Pr) is as follows: For braces acting in TENSION: Page 14 of 20 nullnull null nullDBnull/nullnullnullnull For braces acting in COMPRESSION: Pr null nullnullnullnull/nullnullnullnull The lightweight concrete anchor tables 9.3.5.12.2(a) and (b) were based on sand lightweight concrete which r

11、epresents a conservative assumption for the strength of the material. For seismic applications cracked concrete was assumed. 6. Add a new Annex E.7 to read as follows: E.7 Allowable Loads for Concrete Anchors. The following sections provide step-by-step examples of the procedures for determining the

12、 allowable loads for concrete anchors as they are found in Tables 9.3.5.12.2(a) through 9.3.5.12.2(f). Tables 9.3.5.12.2(a) through (f) were developed using the prying factors found in Table E.7(a) and the representative strength design seismic shear and tension values for concrete anchors found in

13、Table E.7(b). Table E.7(a) Prying Factors for Table 9.3.5.12.2(a) through Table 9.3.5.12.2(f) Concrete Anchors Pr Range Fig. 9.3.5.12.1 Designated Angle Category A B C D E F G H I Lowest 2.0 1.1 0.7 1.2 1.1 1.1 1.4 0.9 0.8 Low 3.5 1.8 1.0 1.7 1.8 2.0 1.9 1.3 1.1 High 5.0 2.5 1.3 2.2 2.5 2.9 2.4 1.7

14、1.4 Highest 6.5 3.2 1.6 2.7 3.2 3.8 2.9 2.1 1.7 Page 15 of 20 Table E.7(b)Representative Strength Design Seismic Shear and Tension Values Used for Concrete Anchors Wedge Anchors in 3000 psi LW Sand Concrete on Metal Deck Anchor Dia. (in.) Nominal Embedment (in.) LRFD Tension (lbs.) LRFD Shear (lbs.)

15、 3/8 2 573 11721/2 2.375 804 1616 5/8 3.125 1102 1744 Wedge Anchors in 3000 psi LW Sand Concrete Anchor Dia. (in.) Nominal Embedment (in.) LRFD Tension (lbs.) LRFD Shear (lbs.) 3/8 2 637 5501/2 3.625 871 745 5/8 3.875 1403 1140 3/4 4.125 1908 1932 Wedge Anchors in 3000 psi NW Concrete Anchor Dia. (i

16、n.) Nominal Embedment (in.) LRFD Tension (lbs.) LRFD Shear (lbs.) 3/8 2 1063 9171/2 3.625 2639 2052 5/8 3.875 3004 2489 3/4 4.125 3179 3206 Wedge Anchors in 4000 psi NW Concrete Anchor Dia. (in.) Nominal Embedment (in.) LRFD Tension (lbs.) LRFD Shear (lbs.) 3/8 2 1226 10881/2 3.625 2601 2369 5/8 3.8

17、75 3469 2586 3/4 4.125 3671 3717 Page 16 of 20 Wedge Anchors in 6000 psi NW Concrete Anchor Dia. (in.) Nominal Embedment (in.) LRFD Tension (lbs.) LRFD Shear (lbs.) 3/8 2.25 1592 1322 1/2 3.625 3186 2902 5/8 3.875 4249 3167 3/4 4.125 4497 4553 Undercut Anchors in 3000 psi NW Concrete Anchor Dia. (in

18、.) Nominal Embedment (in.) LRFD Tension (lbs.) LRFD Shear (lbs.) 3/8 5 4096 18671/2 7 5322 2800 5/8 9.5 6942 56753/4 12 10182 9460 E.7.1 Procedure for Selecting a Wedge Anchor Using Tables 9.3.5.12.2(a) through 9.3.5.12.2(f). Step 1. Determine the ASD Horizontal Earthquake Load Fpw. Step 1a. Calcula

19、te the weight of the water-filled pipe within the Zone of Influence of the brace. Step 1b. Find the applicable Seismic Coefficient Cp in Table 9.3.5.9.3 Step 1c. Multiply the Zone of Influence weight by Cp to determine the ASD Horizontal Earthquake Load Fpw. Step 2. Select a concrete anchor from Tab

20、les 9.3.5.12.2(a) through 9.3.5.12.2(f) with a maximum load capacity that is greater than the calculated horizontal earthquake load Fpw from Step 1. Step 2a. Locate the table for the applicable concrete strength. Step 2b. Find the column in the selected table for the applicable designated angle cate

21、gory (A thru I) and the appropriate prying factor Pr range. Step 2c. Scan down the category column to find a concrete anchor diameter, embedment depth, and maximum load capacity that is greater than the calculated horizontal earthquake load Fpw from Step 1. (ALTERNATIVE) Step 2. As an alternative to

22、 using the maximum load values in Tables 9.3.5.12.2(a) through 9.3.5.12.2(f), select an AC355.2 seismically pre-qualified concrete anchor with a load-carrying capacity that exceeds the calculated Fpw, with calculations, including the effects of prying, based on seismic shear and tension values taken

23、 from an ICC-ES Report and calculated in accordance with ACI 318, Chapter 17 and adjusted to ASD values by multiplying by 0.43 per 9.3.5.12.8.3(D). Page 17 of 20 EXAMPLE Step 1. Zone of Influence Fpw. Step 1a. 40 ft. of 2” Sch. 10 pipe plus 15% Fitting Allowance 40 x 5.89 lbs/ft x 1.15 = 270.94 lbs

24、Step 1b. Seismic Coefficient Cp from Table 9.3.5.9.3 Cp = 0.35 Step 1c. Fpw = 0.35 x 270.94 = 94.8 lbs. Step 2. Select a concrete anchor from Tables 9.3.5.12.2(a) through 9.3.5.12.2(f). Step 2a. Using the table for 4000 psi Normal Weight Concrete. Step 2b. Fastener Orientation “A” assume the manufac

25、turers prying factor is 3.0 for the fitting. Use the Pr range of 2.1 3.5. Step 2c. Allowable Fpw on 3/8” dia. with 2” embedment = 135 lbs and is greater than the Calculated Fpw of 94.8 lbs. E.7.2 Calculation Procedure for Maximum Load Capacity of Concrete Anchors. This example shows how the effects

26、of prying and brace angle are calculated. Step 1. Determine the Allowable Seismic Tension Value (Tallow) and the Allowable Seismic Shear Value (Vallow) for the anchor, based on data found in the in the anchor manufacturers approved evaluation report. Note that, in this example, it is assumed the eva

27、luation report provides the allowable tension and shear capacities. If this is not the case, then the strength design anchor capacities must be determined using the procedures in ACI 318, Chapter 17, which are then converted to ASD values by dividing by a factor of 1.4. As an alternative to calculat

28、ing the Allowable Seismic Tension Value (Tallow) and the Allowable Seismic Shear Value (Vallow) for the anchor, the seismic tension and shear values that were used to calculate the Figure 9.3.5.12.1 for anchor allowable load tables may be used. Step 1a. Find the ASD Seismic Tension capacity (Tallow)

29、 for the anchor according to the strength of concrete, diameter of the anchor, and embedment depth of the anchor. Divide the ASD tension value by 2.0 and then multiply by 1.2. Step 1b. Find the ASD Seismic Shear capacity (Vallow) for the anchor according to the strength of concrete, diameter of the

30、anchor, and embedment depth of the anchor. Divide the ASD shear value by 2.0 and then multiply by 1.2. Step 2. Calculate the Applied Seismic Tension (T) and the Applied Seismic Shear (V) based on the Calculated Horizontal Earthquake Load Fpw. Step 2a. Calculate the designated angle category Applied

31、Tension Factor Including the Effects of Prying (Pr) using the following formulas: Category “A”, “B” and “C” nullnull null nullnullCnullAnullnullnullnullnull nullDnull/A Category “D”, “E” and “F” nullnull null nullnullCnullAnullnull nullDnullnullnullnullnullnull/A Page 18 of 20 Category “G”, “H” and

32、“I” nullnull null nullnullnullnull/ nullnullnullnull Step 2b. Calculate the ASD Applied Seismic Tension (T) on the anchor, including the effects of prying, and when applied at the applicable brace angle from vertical and the designated angle category (A thru I) using the following formula: T = Fpw x

33、 Pr Step 2c. Calculate the ASD Applied Seismic Shear (V) on the anchor, when applied at the applicable brace angle from vertical and the designated angle category (A thru I) using the following formulas: Category “A”, “B” and “C” V = Fpw Category “D”, “E” and “F” null null nullnullnull/nullnullnulln

34、ull Category “G”, “H” and “I” V = Fpw/Sin Step 3. Check the anchor for combined tension and shear loads using the formula: nullnullnullnullnullnullnullnullnull null nullnullnullnullnullnullnullnullnull null1.2 Confirm T/Tallow & V/Vallow = 1.0 EXAMPLE Sample Calculation, Maximum Load Capacity of Con

35、crete Anchors as Shown in Tables 9.3.5.12.2(a) through 9.3.5.12.2(f) In this example, a sample calculation is provided showing how the values in Tables 9.3.5.12.2(a) through 9.3.5.12.2(f) were calculated. Step 1. Determine the Allowable Seismic Tension Value (Tallow) and the Allowable Seismic Shear

36、Value (Vallow) for a concrete anchor in Figure 9.3.5.12.1. Step 1a. The Table E.7(b) Strength Design Seismic Tension Value (Tallow) for a 1/2” Carbon Steel Anchor with 3 5/8” Embedment Depth in 4,000 psi Normal Weight Concrete is 2601 lbs. Therefore, the Allowable Stress Design Seismic Tension Value

37、 (Tallow) is 2601 / 1.4 / 2.0 x 1.2 = 1115 lbs. Step 1b. The Table E.7(b) Strength Design Seismic Shear Value (Vallow) for a 1/2” Carbon Steel Anchor with 3 5/8” embedment is 2369 lbs. Therefore, the Allowable Stress Design Seismic Shear Value (Vallow) is 2369 / 1.4 / 2.0 x 1.2 = 1015 lbs. Page 19 o

38、f 20 Step 2. Using the Applied Seismic Tension Value (T) and the Applied Seismic Shear Value (V) based on an ASD Horizontal Earthquake Load (Fpw) of 170 lbs, a 30obrace angle from vertical and designated angle category “A”. Step 2a. Calculate the ASD Applied Seismic Tension Value (T) on the anchor,

39、including the effects of prying, using the formula: nullnullnullnullnullnull nullnullCnullAnullnullnullnullnull nullDnullnull/A where: T = applied service tension load including the effect of prying Fpw = Horizontal Earthquake Load (Fpw = 170) Tan = Tangent of Brace Angle from vertical (Tannull 30o=

40、 0.5774) A = 0.7500 B = 1.5000 C = 2.6250 D = 1.0000 T = Fpw x Pr null null nullnullnullnull nullnull2.625null 0.750.5774nullnull1.0nullnull/0.75 null null nullnullnullnull null5.8452null 1.0nullnull/0.75 nullnullnullnullnullnull nullnull5.8452nullnull 1.0nullnull/0.75 nullnullnullnullnull null4.845

41、10.75null null null nullnullnull x 6.46 null null 170 lbs x 6.46 null 1098.2 lbs Step 2b. The ASD Applied Seismic Shear Value (V) on the anchor for anchor orientations “A”, “B” & “C” is equal to the ASD Horizontal Earthquake Load (Fpw) = 170 lbs. Step 3 Calculate the maximum Allowable Horizontal Ear

42、thquake Load Fpw using the formula: Page 20 of 20 nullnullnullnullnullnullnullnullnull null nullnullnullnullnullnullnullnullnull null1.2 null1098.2 1115nullnull null1701015null null .9849null .1675 null 1.1524 nullnull null.nullnull Issue Date: August 18, 2015 Effective Date: September 7, 2015 (Note: For further information on NFPA Codes and Standards, please see www.nfpa.org/codelist) Copyright 2015 All Rights Reserved NATIONAL FIRE PROTECTION ASSOCIATION