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FEB-13-2003 THU 10� 10 AM ENGINEERIMG TECHNICAI FAX N0, 6054981299 P, 08 <br /> 3.7 Horiz�r�tal Shear 3.8 fina! Allowable t�oad <br /> 3.7_t Stati�.af Mar�ent The fina!ailow�ble load on lhe p�.nel i�tPir Ic�w�sf <br /> of the figurc;s obtal�ed in Seciion 3.4 ihrui�c�i� 3.1 <br /> Th� (Z to be used in the equation for horizontal above. � <br /> �t-sear inclur�es tha statical moment of all p�rallel- <br /> grain m�lerlaf al�ove (or be�ow) the neutral ax(s. <br /> ��f�►.,e, ihe valuo 01 (�5 obtained abave for rolling 4. Waif Pan�el Design <br /> Sh4ar f�r th� top skin cannot be used Since it will <br /> . not includa ihe stringers,and c��nerally will not in• 4.1 General <br /> clude the hottom paraliel piy of tho top skin. <br /> Strassed-skin��nels usetf for wa11s,ar�ti��=����palica- <br /> Again a transformeei sertion is required, to allow tions where tf�Ayare loaded in axial curnpres:3inri,can <br /> for d4fferc;nces In mo�ulus of el2sticity, in figuring bedesigr�ed inaccorclanc�withstand��rd�aruceci��rr.s. <br /> b�ot�� (� anci effeclive i. Since the wliole deptti of �n practico,when tf�ese panels 3r�U5�d f(3�W<<lfs,tf��ar <br /> the F,lywo�d Is involved, the area is tttiat Ifsted In thickness is usually determin�d by a��a�;,�t�2��cc, <br /> , lP�e PDS. The "d" dlstance Is to the rnid-depth of acoustics,or lrtisulatian requirernanls,an�sarricjLim�� <br /> tito sf�ir�. [3ut the ef Fectiveness of the skin must be by the necessity for wi+�d rosislarzce, E�ut�f9lttr�rn t�y <br /> "ir�n�farned" to be c�mp�tibie with ihe stringer. their actual Eoad-boaring c�pacity as colur��n�. <br /> 7hus the (�y of th� pancl is given 3n ihe fotlowing <br /> (��lt�'�tlOrl: <br /> 4.2 Vert'scal-Load Forrrr��(a <br /> av = nstrin ers + �skin x <br /> 9 Qsk9n Few practleal en�� joints fot' stressed•skit7 �,�n��ls <br /> ��tr[ngers wil( pravEde any a�,prQciak�le clegr�:L af fixity. <br /> Under vertical 1oad, therefore, panels will br;f�av� <br /> , Nate th�t 1he neutra� axfs is as determined for as pfn•cnded colum,�s. 'fhe pin�cr�ciccf colun'ir► <br /> dt�ilaction, in Seciion 3.4,2. equations r�duct� to: <br /> � 3.�,'t A1iavJa�Ie Shc�r Slross p - 3'�j� �I� or F A <br /> AIfo�Na�le horizontal shear stresses for stress• a � ��� �2 � " <br /> � <br /> c�raciP 1��rnL�r�r�re given in the NATIONAL DESIGN <br /> Sf�EG(�lC��1'ION FOR WOOD CUNS7RUCTfON W�1tC�1C4�c:r i� !G�� <br /> (N[�S). <br /> where <br /> . �.7 3 Rlla�;�alife Load Pa - aflowable veriiC�i lo�:zcf ar► thc <br /> panel (Ib) <br /> The equatior•� fo� allowable unifiur�z� load on a <br /> ' strass�r,i-sltin panel is as follows; � - �pP�"opr'i�t� Cr'tOtlulus of rl�:;ticity <br /> (sec bclowj (psi} <br /> 2tE�9� �vt Ig � �ross rT�orr�ent of incrtia af ��ur�e1 <br /> W� — ��y�. Fsi'— about neutr�71 axis (in.`�j <br /> L = Unsupporteci verfica( h���ic}4�t o( <br /> wl��:rc pane� (fi) <br /> ���v � altowable load based on F� _ �,lbwabl� con•ipres�ivnstrc�r�,sfor <br /> t�orizontal 5he�r sEress (psf} plywood skins (psi) <br /> E1� � stiffness faCtor, computed in A - total v�rtic�l-c�rain rnal��ri�rl c�i <br /> " Section 3,4,3(Ib-in.�) Stringers ��td �ki��s {in.�}. <br /> rrv„ = allowable hOrizontal shear stress Wherc the moduli af ela5ticity of sl;in; aric! <br /> �n the �umber stringcrs (psi) stringers ar� noarly al"s4ce, thC �110dUluS vt a?E1SiiC1- <br /> t = �um o( stringQr widths for the ty of the skins rn,�y bo usecf. Othertivise, r�lci.�f_�tU <br /> P��p� (��-1 E19 as in Section 3.q.3 for u:;i: In ttiis eq�ic;tlr,�r-�. <br /> c�„ : f�rsi moment a�out the neutral <br /> ` �xis oF a11 paraliel-c�rain rn��erial <br /> �bove (or below) the neutral axi& <br /> of the 4-ft-wide pancl (in,3) � <br /> L - lengti7 of the pancl (ft) . <br /> i=�t w rnodulus of elasticity of strinc��rs �.._ � <br /> ; if>si}. ��j�.. <br />