TESTING APPLICATION STANDARD (TAS) No TEST PROCEDURE FOR WIND TUNNEL TESTING OF AIR PERMEABLE, RIGID, DISCONTINUOUS ROOF SYSTEMS

Transcription

1 TESTING APPLIATION STANDARD (TAS) No TEST PROEDURE FOR WIND TUNNEL TESTING OF AIR PERMEABLE, RIGID, DISONTINUOUS ROOF SYSTEMS Scope: 1.1 This protoco covers procedures for determining the wind characteristics of an air permeabe, rigid, discontinuous roof system. The test procedures herein provide the pressure distribution occurring, at various wind speeds, on the top and bottom surfaces of an instrumented component within a test specimen consisting of a wood deck; underayment; and, an air permeabe, rigid, discontinuous roof system. The cacuations herein determine the coefficients of pressure ( P ) aong the top and bottom surfaces of the instrumented component; the coefficient of ift ( L ); the coefficient of moment ( Ma ); and the aerodynamic mutipier () for the instrumented component. NOTE: The coefficient of ift ( L ) need ony be determined for S shaped cay or concrete tie systems. In addition, the coefficient of moment ( Ma ) need not be determined for S shaped cay or concrete tie systems. This is discussed further in Section The aerodynamic mutipier (), determined under this protoco, is used to determine the attachment resistance (M f ) required for the particuar type of system instaed on a particuar buiding in the high-veocity hurricane zone jurisdiction, in compiance with the attachment cacuations set forth in RAS 127 and the wind oad requirements set forth in hapter 16 (High-Veocity Hurricane Zones) of the Forida Buiding ode, Buiding. Referenced Documents: 3. TAS 102 Test Procedure for Static Upift Testing of Mechanicay Attached, Rigid Roof Systems TAS 102(A) Test Procedure for Static Upift Testing of ipped, Rigid Roof Systems TAS 116 Test Procedure for Air Permeabiity Testing of Rigid, Discontinuous Roof Systems 2.3 Redand Technoogy - New Technoogy & Product Deveopment entre Fixing Studies for MRTI Norma Weight Ties - SBI Submission 2.4 ASTM Standards: E 380 Excerpts from the Standard Practice for Use of the Internationa System of Units (SI) (the Modernized Metric System) 2.5 Roof onsutants Institute: Gossary of Terms Terminoogy & Units: 3.1 Definitions For definitions of terms in this protoco, refer to hapters 2 and Section 1513 of the Forida Buiding ode, Buiding; and/or Fixing Studies for MRTI Norma Weight Ties; and/or the RI Gossary of Terms. Definitions from the Forida Buiding ode, Buiding sha take precedence. 3.2 Units For conversion of U.S. customary units to SI units, refer to ASTM E The Forida Buiding ode, Buiding. 4. Significance and Use: 2.2 Appication Standards: TAS 101 Test Procedure for Static Upift Testing of Mortar or Adhesive Set Tie Systems 4.1 Use of this protoco is imited to systems which are air permeabe, as determined in compiance with TAS 116 or deemed air permeabe by the chief code compiance officer, in which the unseaed, overap FLORIDA BUILDING ODE TEST PROTOOLS HVHZ (TAS)

2 5. 6. ping, rigid components have a ength between 1.0 and 1.75 feet; an exposed width between 0.73 and 1.25 feet; and a thickness not greater than 1.3 in. Note: The hief ode ompiance Officer may waive the requirement for air permeabiity testing in compiance with TAS The procedures outined in this protoco provide a means of determining the aerodynamic mutipier () for the air permeabe, rigid, discontinuous roof system being tested. This aerodynamic mutipier () sha be isted in the system manufacturer s Product Approva for use in RAS 127, in combination with the rigid component s restoring moment due to gravity (M g ), determined in compiance with TAS 101 for mortar or adhesive set tie systems; TAS 102 for mechanicay attached, rigid, discontinuous roof systems; TAS 102(A) for mechanicay attached systems accompanied by a cip; and the wind oad requirements set forth in hapter 16 (High-Veocity Hurricane Zones) of the Forida Buiding ode, Buiding. Apparatus: 5.1 The wind tunne: The wind tunne sha be an open circuit wind tunne capabe of producing wind speeds up to 110 mies per hour. If the wind tunne is unabe to produce wind speeds of this magnitude, a wind constrictor of appropriate size sha be utiized to generate such wind speeds. The wind constrictor sha be fuy seaed to around the edges to prevent air eakage. (See Figure 1, attached.) A penum chamber sha be ocated beow area B of the test specimen, as noted in Figure 2, attached, to simuate an interna coefficient of pressure of Precautions: 6.1 This protoco may invove hazardous materias, operations and equipment. This protoco does not purport to address a of the safety probems associated with its 7. use. It is the responsibiity of the user to consut and estabish appropriate safety and heath practices and determine the appicabiity of reguatory imitations prior to use. Test Specimen the test specimen sha be constructed within the wind tunne to avoid possibe damage which may occur during transport. 7.1 Deck: The wood deck sheathing sha be APA 32 / 16 span rated sheathing of 15 / 32 inch thickness, attached with 8d common nais at 6 inches o.c. at pane edges and 12 inches o.c. at intermediate supports. One transverse joint sha be incuded to simuate the potentia for air eakage from beow. 7.2 Underayment The underayment sha be a standard 30/90 system with a 30 ASTM D 226, type II anchor sheet and an ASTM D 249 minera surface ro roofing as the top py The anchor sheet sha be mechanicay attached to the wood sheathing, with 12 ga. roofing nais and 1 5 / 8 inch tin caps, in a 12 inch grid pattern staggered in two rows in the fied and 6 inches o.c. at any aps. The minera surface top py sha be appied in a fu mopping of ASTM D 312, type IV asphat The underayment edges sha be set in adhesive to provide an airtight, continuous sea around the perimeter of the test deck. 7.3 Area A, noted in Figure 2, sha be used to provide the boundary conditions for the air fow over Area B. The rigid components in Area A sha be rigidy attached to the substrate and sha extend not ess than four courses. The rigid components in Area B sha be attached or bonded in compiance with the manufacturer s pubished instaation instructions and sha extend not ess than five courses. The width of the test specimen sha be not ess than four aid components. (TAS) FLORIDA BUILDING ODE TEST PROTOOLS HVHZ

3 7.4 Mortar set tie systems: Mortar mix sha have a roofing component product approva for use with the mortar set tie system and sha be in compiance with TAS Mortar sha be mixed using the mixing ratio specified in the mortar manufacturer s Product Approva Mortar fow sha be determined using a cone penetrometer test, in compiance with ASTM 780 (Appendix A1), the resuts of which sha be 2 1 / / 8 inch ( mm) of penetration Mortar set tie sha be appied in a bed of mortar, the amount of which sha be a 10 inch trowe fied with mortar. The 10 inch trowe sha be paced at the same ocation beneath each tie on the test specimen with the exception of the instrumented tie noted in Section 7.9, herein Mortar set tie systems sha be aowed to cure at ambient conditions for a period of 24 hours prior to conducting the wind tunne test. 7.5 Adhesive Set Tie Systems: Adhesive sha have a roofing component product approva for use with the adhesive set tie system which is being tested and sha be appied in compiance with the provisions set forth in that approva Adhesive set tie systems sha be aowed to cure for a period of 24 hours prior to conducting the wind tunne test. 7.6 Mechanicay Attached, Rigid, Discontinuous Roof Systems Each component sha be instaed in compiance with the system manufacturer s pubished instaation instructions; the current Product Approva; and/or the minimum requirements set forth in hapter 15 (High-Veocity Hurricane Zones) of the Forida Buiding ode, Buiding. The requirements of the Forida Buiding ode, Buiding sha take precedence omponent attachment fasteners (i.e. nais, screws, tie straps, etc.) sha be those recommended by the system manufacturer s pubished instaation instructions. Nais sha be not ess than inch in diameter and minimum screws sha be #8 diameter screw fasteners. omponent attachment fasteners sha meet the corrosion requirements set forth in TAS 114, Appendix E Battens (if appicabe): Horizonta batten system Horizonta battens sha be of nomina 1 inch by 2 inch dimensiona umber and sha be spaced to provide a minimum 3 inch head ap, or to match the interocking configuration of the component s profie. Appy one 1 / 4 inch bead of approved seaant to the underside of horizonta battens and attach to the test deck at 6 inches o.c. using 12 ga. roofing nais, ensuring each nai penetrates the seaant bead ounter batten system Vertica battens sha be nomina 1 inch by 4 inch umber and sha be spaced 24 inches over the intermediate supports (trusses). Appy one 1 / 4 inch bead of approved seaant to the underside of vertica battens and attach to the test deck at 6 inches o.c. using 12 ga. roofing nais. Horizonta battens (counter battens) sha be as noted in Section , naied to the FLORIDA BUILDING ODE TEST PROTOOLS HVHZ (TAS)

4 inch by 4 inch vertica battens using 12 ga. roofing nais of sufficient ength to penetrate both battens. 7.7 Pressure Measurement, Top Surface One component, ocated in the center of Area B, sha be instrumented with 20 pressure tappings (i.e. 20 hoes dried through the body and aong the centerine of the component). The first 10 pressure tappings sha be equay spaced, toward the nose of the component, within the first 1 / 3 of the component s ength. The remaining 10 pressure tappings sha be equay spaced within the remaining 2 / 3 of the component s ength The tappings sha be sized to accept tubes which are soidy fixed through the hoes at the bottom of the component. The opposite end of the tubes sha be connected to a suitabe pressure measuring device which permits samping of pressures in a 20 tubes. These pressure tappings aow for measurement of the static pressure distribution on the component s top surface. 7.8 Pressure measurement, bottom surface The instrumented component, noted in Section 7.7, sha aso be instrumented with seven (7) simiar pressure tubes instaed on the bottom surface, parae aong the ength of the component. The first 4 pressure tubes sha be equay spaced, toward the nose of the component, within the first 1 / 3 of the component s ength. The remaining 3 pressure tubes sha be equay spaced within the remaining 2 / 3 of the component s ength These pressure tubes aow for measurement of the static pressure distribution on the component s bottom surface and sha be connected to a simiar pressure measuring device. 7.9 For mortar or adhesive set tie systems, the instrumented tie sha be instaed with adhesive appied around the tie perimeter, as cose as possibe, but without interfering with the pressure tappings. The adhesive sha have simiar fow properties to those noted in Section and sha be appied to simuate the configuration of a typica mortar or adhesive patty A components aong the side of the test specimen sha be seaed with adhesive tape to prevent air fow between the underside of the components and the sow moving ayer of air on the side was of the wind tunne The test specimen sha be inspected by a professiona engineer or registered roof onsutant, who sha certify, in the fina report, that it was constructed in compiance with the provisions of this protoco. aibration: 8.1 Pressure tubes: Each pressure tube from the tapped component sha be checked for eakage by appying a pressure to the tube and camping it off. Leakage sha be identified by any pressure drop recorded by the pressure measuring device. Any pressure tube which exhibits eakage sha be repaired or repaced. 8.2 Pitot-static tube: The pitot-static tube sha be cross-checked against a cup anemometer which gives an eectrica output. 8.3 Manometer: The manometer(s) sha be cross-checked against an eectrica pressure transducer. Test Procedure: 9.1 onstruct the test specimen in testing position in the wind tunne as noted in Section Position the pitot-static tube 4 inches above the test specimen at the junction be- (TAS) FLORIDA BUILDING ODE TEST PROTOOLS HVHZ

5 tween Area A and area B. Attach the pitot-static tube to pressure tube connections which aow measurement of the tota pressure (p tota ) and the free stream static pressure (p ). The veocity pressure (q) sha be determined by subtracting the free stream static pressure (p ) from the tota pressure (p tota ), as noted in Section oefficient of pressure ( P ) Surface: Determine the coefficient of pressure for each of the top and bottom pressure tappings, ( Pt and Pb respectivey) using the foowing equations. Bottom Surface: 9.3 Turn the wind generator on and set the pressure in the penum chamber to refect an interna pressure coefficient of pt Pt P = q Pb Pb P = q Begin air fow over the test specimen at a wind speed of 70 mph, as measured at the pitot-static tube position, and hod unti a pressure readings have stabiized. When pressure readings have stabiized, record the pressure readings on the top and bottom surfaces of the instrumented component. 9.5 Increase the wind speed to 80 mph and hod unti a pressure readings have stabiized. When pressure readings have stabiized, record the pressure readings on the top and bottom surfaces of the instrumented component. Repeat this procedure in 10 mph increments unti a wind speed of 110 mph is reached or unti any portion of the test specimen experiences wind reated damage. 9.6 Tabuate a of the top and bottom surface pressure readings for each wind speed at which pressure measurements were taken. Any system which experiences wind reated damage prior to recording pressure measurements for the 90 mph windspeed sha be considered as a re-test. acuations The foowing cacuations sha be performed for each of the wind speeds at which pressure measurements were taken Veocity Pressure (q) Determine the veocity pressure (q) incurred over the test specimen by subtracting the free stream static pressure (p ) from the tota pressure (p tota ). q = p tota - p Pt P t Pb P b P q = coefficient of pressure (top surface); = oca pressure on component (top surface); = coefficient of pressure (bottom surface); = oca pressure on component (bottom surface); = free stream static pressure; and, = veocity pressure 10.3 oefficient of Lift ( L ) the coefficient of ift ( L ) need ony be determined for S shaped cay or concrete tie systems. This is discussed further in Section L = Determine the coefficient of ift ( L ) for S shaped cay or concrete tie systems using the coefficients of pressure ( Pt and Pb ) from Section 10.2 and the foowing equation. 7 0 L Pb Pt δ barea δ tarea 20 Pb δ barea Pt δ tarea 0 b b = coefficient of ift; = coefficient of pressure (bottom surface; = coefficient of pressure (top surface); = eementa area at pressure tapping (bottom surface); = eementa area at pressure tapping (top surface); 2007 FLORIDA BUILDING ODE TEST PROTOOLS HVHZ (TAS)

6 Ma b = tie ength; and = tie cover width If the variation of L vaues obtained over the wind speed range is no more than 5 percent, then the average vaue of L sha be evauated and used to determine the aerodynamic mutipier (), as noted in Section If the variation in L vaues is greater than 5 percent, then the vaue obtained at the highest wind speed sha be utiized oefficient of Moment ( Ma ) coefficient of moment ( Ma ) need not be determined for S shaped cay or concrete tie systems. = Determine the coefficient of moment ( Ma ) using the coefficients of pressure ( Pt and Pb ) from 10.2 and the foowing equation. 20 Pb b δ barea Pt t δ tarea Ma Pb Pt δ barea δ tarea b t b b b = coefficient of moment; = coefficient of pressure (bottom surface; = coefficient of pressure (top surface); = eementa area at pressure tapping (bottom surface); = eementa area at pressure tapping (top surface); = moment arm acting at each pressure tapping (bottom surface); = moment arm acting at each pressure tapping (top surface); = component ength; and = component cover width If the variation of Ma vaues obtained over the wind speed range is no more than 5 percent, then the average vaue of Ma sha be evauated and used to determine the aerodynamic mutipier (), as noted in Section If the variation in Ma vaues is greater than 5 percent, then the vaue obtained at the highest wind speed sha be utiized Aerodynamic mutipier (λ) (for S shaped cay or concrete tie systems) Due to the shape and attachment point of S shaped cay or concrete tie, the axis of rotation is different from that of other rigid, discontinuous roof systems and the aerodynamic mutipier (λ) for these ties must be based on the aerodynamic moment about this axis. For this reason, the coefficient of moment ( Ma ) for such tie systems needs to be an adjusted vaue ( Ma ) to refect rotation about this axis Determine the adjusted coefficient of moment ( Ma ) using the coefficient of ift ( L ) from Section 10.3 and the foowing equation. = Ma L Ma = adjusted coefficient of moment; L = coefficient of ift; and = tie ength Determine the aerodynamic mutipier () for S shaped cay or concrete tie systems using the adjusted coefficient of moment ( Ma ) from Section and the foowing equation. λ λ= b M a = aerodynamic mutipier; 2 Ma = adjusted coefficient of moment; b = tie cover width; and = tie ength. (TAS) FLORIDA BUILDING ODE TEST PROTOOLS HVHZ

7 The aerodynamic mutipier (λ) sha be isted in the S shaped cay or concrete tie system manufacturer s Product Approva for reference Aerodynamic Mutipier (λ) - (for a systems other than S shaped cay or concrete tie systems) Determine the aerodynamic mutipier (λ) for the system using the coefficient of moment ( Ma ), from Section 10.4 and the foowing equation. λ = Ma b 2 λ = aerodynamic mutipier; Ma = adjusted coefficient of moment; b Report: = tie cover width; and = tie ength The aerodynamic mutipier (λ) sha be isted in the manufacturer s Product Approva for reference The fina report sha incude the foowing: A description and sketch of the component, incuding the manufacturer and type of air permeabe, rigid, discontinuous roof system A detaied report of the test specimen construction, incuding a photograph of the test specimen and certification by a professiona engineer or registered roof consutant that the test specimen was constructed in compiance with the specifications of this Protoco Equipment caibration data or ogs, certifying that the equipment was caibrated, in compiance with the provisions of this Protoco, prior to conducting the test Tabuated data on pressure measurements on the top and bottom surfaces of the instrumented component for each wind speed to which pressure measurements were taken oefficient of pressure cacuations for the top and bottom pressure tapping measurements ( Pt and Pb, respectivey) using the tabuated data noted in Tabuate the resuts from these cacuations oefficient of ift ( L ) cacuations, incuding confirmation that the variation in resuts is ess than 5 percent. If the variation is ess than 5 percent, incude determination of an average L vaue. (These cacuations are ony required for S shaped cay or concrete tie systems.) Adjusted coefficient of moment ( Ma ) cacuations and resuts oefficient of moment ( Ma ) cacuations, incuding confirmation that the variation in resuts is ess than 5 percent. If the variation is ess than 5 percent, incude determination of the average of the Ma vaues. If the variation is greater than 5 percent, the Ma vaue at the maximum wind speed sha be utiized to determine the aerodynamic mutipier (). These cacuations are not required for S shaped cay or concrete tie systems Aerodynamic mutipier (λ) cacuations from Section 10.5 for S shaped cay or concrete tie systems or from Section 10.6 for a other systems Photographs of the foowing: the test specimen prior to the test; the test specimen after the test; and, the instrumented component (showing the pressure tappings and tubes 2007 FLORIDA BUILDING ODE TEST PROTOOLS HVHZ (TAS)

8 on the top and bottom surfaces of the component) The test report sha be signed and seaed by a professiona engineer or a registered roof consutant. NOTE: If the coefficients noted in Section 10 are determined with a computer program, provide confirmation that the equations in the program are in compiance with the provisions of this protoco. If this is the case, the report requirements noted in Sections through sha not be required. FIGURE 1 WIND TUNNEL TEST APPARATUS (TAS) FLORIDA BUILDING ODE TEST PROTOOLS HVHZ

9 FIGURE 2 WIND TUNNEL TEST APPARATUS (SIDE VIEW) 2007 FLORIDA BUILDING ODE TEST PROTOOLS HVHZ (TAS)

10 (TAS) FLORIDA BUILDING ODE TEST PROTOOLS HVHZ