ENGINEERED DESIGN OF SIP PANELS USING NTA LISTING REPORT DATA

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1 ENGINEERED DESIGN OF SI ANELS USING NTA LISTING REORT DATA 1. SCOE 1.1. GENERAL This doument applies to strutural insulated panels (SIs), whih shall be deined as a strutural aing material with a oam ore. This doument does not apply to the design o reinorement materials whih may be inorporated into SIs, suh as dimensional lumber or old-ormed steel. All other materials shall be designed in aordane with the appropriate ode adopted design standards. It is intended that this doument be used in onjuntion with ompetent engineering design, aurate abriation, and adequate supervision o onstrution. NTA, In. does not assume any responsibility or error or omissions in this doument, nor or engineering design, plans or onstrution prepared rom it. It shall be the inal responsibility o the designer to relate design assumptions and reerene design value, and to make design adjustments appropriate to the end use. 1.. DESIGN ROCEDURES This doument provides requirements or the design o SI panels by the Allowable Stress Design (ASD) method. The tehnial basis or this doument is the AA lywood Design Speiiation Supplement 4 Design & Fabriation o lywood Sandwih anels 1, whih is adopted by reerene in the International Building Code (IBC). Some provisions o the design guide have been modiied to more losely model the atual behavior o the SI system desribed in this report. The design proedures provided herein generally assume uniorm loads applied to a simply supported member. General loading and support onditions may be evaluated using rational analysis methods onsistent with the methodology provided herein. I inite element analysis sotware is used, the designer must veriy that the sotware onsiders shear deormations between model nodes as most ommerially available inite element sotware pakages only onsider shear deormations at the nodes DESIGN LOADS Minimum design loads shall be in aordane with the building ode under whih the struture is designed, or where appliable, other reognized minimum design load standards SERVICABILITY Strutural systems and members thereo shall be designed to have adequate stiness to limit deletion and lateral drit. The deletions o strutural members shall not exeed the limitations o the building ode under whih the struture is designed, or where appliable, other reognized minimum design load standards LOAD COMBINATIONS Combinations o design load and ores, and load ombinations ators, shall be in aordane with the building ode under whih the struture is designed, or where appliable, other reognized minimum design standards STRESS INCREASE Duration o load inreases in allowable stresses speiied in the National Design Standard or Wood Constrution (NDS) shall not be applied to SI aings or ore materials regardless o omposition LIMITS OF USE This doument applies to NTA, In. listed SI panels only and shall not be used with unlisted SIs or SIs listed/evaluated by other agenies. The design shall be limited to the speii panel thiknesses desribed in the listing report. This doument shall not be applied to spans, heights, or aspet ratios not bounded by the limits o the listing report extrapolation is not permitted. repared by: Eri Tompos age 1 o 9

2 . NOTATION Exept where otherwise noted, the symbols used in this doument have the ollowing meanings: Total deletion due to transverse load (in.) LT Total immediate deletion due to the long-term omponent o the design load (in.) b Deletion due to bending (in.) Deletion o ore under onentrated load applied to aing (in.) i Total immediate deletion due to appliation o a single design load ating alone (in.) s Deletion due to shear (in.) nd Total immediate deletion onsidering seondary (-delta) eets (in.) Α Total ross setional area o aings (in. /t) A v Shear area o panel. For symmetri panels A v 6 ( h + ) (in. /t) Core thikness (in.) C e Eentri load ator, Setion C Fv Size ator or shear, Setion C v Shear support orretion ator e Load eentriity, measured as the distane rom the entroid o the setion to the line o ation o the applied load (in.) E b SI modulus o elastiity under transverse bending (psi) E Elasti modulus o ore under ompressive load (psi) E Elasti modulus o aing under ompressive load (psi) F Allowable aing ompressive stress (psi) F t Allowable aing tensile stress (psi) F v Allowable shear stress (through thikness) (psi) F vip Allowable shear load (in-plane) (pl) G SI shear modulus (psi) h Overall SI thikness (in.) h o Reerene SI thikness or size orretion ators (in.) I SI moment o inertia (in. 4 /t) I Faing moment o inertia (in. 4 /t) K r Time dependent deormation (reep) ator or a speii load type, Setion A3.5.3 L Span length (t) L v Shear span length (t) m Shear size ator exponent M Applied moment (in.-lb/t) Applied axial or onentrated load (lb/t.) r Allowable axial load (lb/t) r Radius o gyration (in.) S SI setion modulus or lexure under transverse loads (in. 3 /t) V Applied shear ore (through thikness) (lb) V ip Applied shear ore (in-plane) pl w Uniorm transverse load (ps) y Distane rom the entroid to the extreme ompression iber (in.) β arameter o relative stiness 3. USE CONSIDERATIONS 3.1. LOAD DURATION Duration o load inreases in allowable stress shall not be applied to SI aings or ores. Duration o load inreases may be applied to the design o onnetions and wood reinorement as permitted in appliable material design speiiations. 3.. MOISTURE repared by: Eri Tompos age o 9

3 This doument applies to SI panels used under dry servie onditions. For SI aings o wood or wood omposites the in-use moisture ontent shall not exeed 19% TEMERATURE This Doument applies to SI panels used as strutural members were sustained temperatures do not exeed 100ºF. 4. BENDING MEMBERS 4.1. GENERAL Eah SI panel subjeted to transverse loads shall be o suiient size and apaity to arry the applied loads without exeeding the allowable design values speiied herein. 4.. SAN OF BENDING MEMBERS For simple, ontinuous and antilevered bending members, the design span shall be taken as the distane rom ae to ae o support. When no bearing is provided, suh as when a panel is supported by a spline only (C v < 1.0), the design span shall extend the ull height/length o the panel BENDING MEMBERS FLEXURE GENERAL anel lexural strength under transverse loading shall satisy both equations below: M F S (Eqn a) M t F S (Eqn b) 4.4. BENDING MEMBERS SHEAR GENERAL The atual shear stress parallel to the aing at the ore to aing interae shall not exeed the adjusted shear design value SHEAR DESIGN EQUATIONS The panel shear strength under transverse loading shall satisy the ollowing equation: V F C C A (Eqn. 4.4.) v Fv v v SHEAR SIZE ADJUSTEMENT FACTOR, C Fv The allowable shear strength shall be multiplied by a adjustment ator or the depth o the panel. The shear size adjustment ator shall be alulated using Equation C m ho Fv (Eqn ) h SUORT ADJUSTEMENT FACTOR, C v For panel ends supported by ull bearing on one aing and uniorm loads applied to the opposite aing, the shear adjustment ator, C v 1.0 (see Figure A4.4.4) For panel ends without bearing, supported by a top/bottom spline only, with uniorm loads applied to either aing, the shear adjustment ator, C v, shall be based on testing speii to the ollowing parameters (see Figure A4.4.4): 1. anel manuaturer; repared by: Eri Tompos age 3 o 9

4 . Spline type, as it relates to the withdrawal/pullout strength o the asteners (e.g. speii gravity or wood plates); 3. Fastener type and penetration Where C v is less than 1.0, the allowable shear strength may be inreased i the spline/astener ombination has a design withdrawal/pullout strength greater than the design withdrawal/pullout strength o the C v assembly. The inrease in strength shall not exeed the dierene in the design withdrawal/pullout strength between the stronger assembly and the C v assembly Figure 4.4.4: C v Support Conditions SHEAR DESIGN FORCE When alulating the shear ore, V, in bending members: a) For panels supported by ull bearing on one aing and uniorm loads applied to the opposite aing (C v 1.0), uniormly distributed loads within a distane rom the supports equal to the depth o the panel, h, shall be permitted to be ignored. b) For all other support and loading onditions (C v < 1.0), no load applied to the panel may be ignored and V shall be taken as the ull reation at the support under onsideration. Figure 4.4.5: Design Shear Fore repared by: Eri Tompos age 4 o 9

5 4.5. BENDING MEMBERS DEFLECTION GENERAL Deletion shall be alulated by standard methods o engineering mehanis onsidering both bending deletions and shear deletions DEFLECTION EQUATIONS Deletion o a simply supported panel under uniorm transverse load only shall be alulated as ollows: 4 5wL wl b + s + (Eqn. 4.5.a) 384E I A G Deletions or panels subjeted to ombined loads shall onsider the eets o axial load (-delta eets). The total deletion o panels under ombined loads may be approximated as ollows. b v nd (Eqn. 4.5.a) 1 r LONG-TERM LOADING Where deletion under long-term loading must be limited, the total deletion, inluding reep eets shall be alulated as ollows: K (Eqn ) T ri i Table 1: Kr Based on Load Type 1 Load Type ES/XS Core Urethane Core D, F, H, T L E, W, S, R, L r, F a Table values are or OSB aings used under dry servie onditions. Load types are as deined in ASCE DEFLECTION LIMITS The total deletion o strutural or non-strutural bending members, inluding onsideration or long-term loading, shall not exeed the more restritive o the ollowing: a) the span divided by 10 (L/10); b) the limitations o the building ode under whih the struture is designed; ) or, other reognized minimum design load standards. repared by: Eri Tompos age 5 o 9

6 4.6. BEARING AND CONCENTRATED LOADS ON FACINGS MINIMUM SUORT WIDTH A minimum support width o 1.5-inhes shall be provided at all supports where the SI is designed or bearing (C v 1.0). The bearing support shall be ontinuous along the end o the panel BEARING STREGNTH Where a ull-depth strutural spline is provided at a point o bearing, the bearing strength shall not exeed the design bearing strength o the aings or spline, whihever is less Where a ull-depth strutural spline is not provided at a point o bearing and the bearing ae o the panel is supported by the ore only. The allowable bearing strength shall be limited to the load produing a long-term total ompression o the ore equal to 1/8-inh. Long term deletions shall be alulated in aordane with Setion The ore ompression deletion shall be alulated using the omponent material properties o the aing and the ore onsidering the aing as a beam on an elasti oundation. Formulas or ommon ases (Figure 4.6..) are provided in Equations 6...a and 6...b. Equations are or loads uniormly applied along the end o the panel. Figure 4.6..: Bearing on Faings Case A: Case B: 3 4E I β (Eqn a) 3 8E I β (Eqn b) 3E E I β 4 (Eqn ) repared by: Eri Tompos age 6 o 9

7 5. COMRESSION MEMBERS 5.1. GENERAL Eah SI panel subjeted to ompressive loads shall be o suiient size and apaity to arry the applied loads without exeeding the allowable design values in this setion COMRESSION MEMBERS LOAD ECCENTRICITY The panel ompression strength under axial loading shall satisy the ollowing equation: e where e CeF A (Eqn a) The eentri load ator shall be alulated using Equation 5.1.1b onsidering a minimum eentriity equal to not less than one-sixth the overall panel thikness ( e h 6 ). C 1 1L se r e (Eqn b) ey ey 1+ + r A Eb AvGI COMRESSION MEMBERS GLOBAL BUCKLING The ritial bukling load or a pinned-pinned olumn under axial loading shall satisy the ollowing equation: r where r 3 ( 1L) π EbI π E bi 1 + ( 1L) AvG (Eqn. 5.1.) COMRESSION MEMBERS BEARING The axial ompressive load shall not exeed the bearing strength o the supporting materials. The bearing strength o the supporting materials shall be veriied in aordane with the appropriate design speiiation. Where one or more o the SI aings are not in bearing, the onnetion between the aings and the spline shall be designed to transer the ull load rom the aings to the plate. 6. TENSION MEMBERS 6.1. GENERAL A ontinuous load path shall be provided to transer tension ores through the struture in a way that does not impart tensile loads to the SI panel aings or ore. repared by: Eri Tompos age 7 o 9

8 7. COMBINED LOADS 7.1. GENERAL anels subjeted to ombined loads shall o suiient size and apaity to arry the applied loads without exeeding the allowable design values in this setion COMBINED COMRESSION, TRANSVERSE BENDING AND IN-LANE SHEAR anel strength under ombined axial ompression, transverse bending and in-plane shear shall satisy the ollowing interation equations: e r M V max ip F S F vip M V max ip F S F vip (Eqn a) (Eqn a) For simply supported beam olumns M max shall equal: M wl max nd (Eqn ) 8. CONNECTIONS 8.1. GENERAL Connetions between SI panels, splines, plates, and non-si assemblies shall be designed in aordane with the appropriate material design standard reerened in the appliable building ode. 9. SHEAR WALLS AND DIAHRAGMS 9.1. GENERAL SI panel shear walls and diaphragms ating as elements o the lateral ore-resisting system shall be designed in aordane with this setion. 9.. DEFINITIONS 9.3. SHEAR WALLS DEFINITIONS SHEAR WALL ANCHORAGE SHEAR WALL STRENGTH SHEAR WALL DEFLECTION 9.4. DIAHRAGMS repared by: Eri Tompos age 8 o 9

9 10. REFERENCES 1. AA. lywood Design Speiiation Supplement 4: Design and Fabriation o lywood Sandwih anels. Doument U814-H. Marh Taylor, S.B., Manbek, H.B., Janowiak, J. J., Hiltunum, D.R. Modeling Strutural Insulated anel (SI) Flexural Creep Deletion. J. Strutural Engineering, Vol. 13, No. 1, Deember, Timoshenko, S.., Gere, J.M. Theory o Elasti Stability. Seond Edition. MGraw-Hill Young, W.C., Budynas, R.G. Roark s Formulas or Stress and Strain. Seventh Edition. MGraw-Hill Zenkert, D. The Handbook o Sandwih Constrution. Engineering Materials Advisory Servies Ltd repared by: Eri Tompos age 9 o 9

ENGINEERED DESIGN OF SIP PANELS USING NTA LISTING REPORT DATA

ENGINEERED DESIGN OF SIP PANELS USING NTA LISTING REPORT DATA ENGINEERED DESIGN OF SI ANELS USING NTA LISTING REORT DATA 1. SCOE 1.1. GENERAL This document applies to structural insulated panels (SIs), which shall be defined as a structural facing material with a