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I DES:d;k 11/07/89 (029/7) DES: t 11/13/89R (c) Capacities of existing materials other than the URM walls themselves may be assumed as indicated in Table A-5 of this Appendix. (d) The capacity/demand ratio (factor of safety) for each element of the seismic force-resisting system shall equal or exceed one (1.0). Any element for which this ratio is less than one shall be considered deficient. (e) The fifty percent (50%) increase in the seismic force factor for shear walls specified in Section 2407(h)4F of the 1985 Edition of the UBC may be omitted in the computation of seismic loads to existing shear walls. (f) URM shall not be considered to have tensile stress capacity. However, tension due to out-of-plane seismic forces applied to URM walls may be neglected for walls within the height-to-thickness ratios specified in Table A-3 of this Appendix, provided that the out-of- plane shear does not exceed the allowable stresses shown in Table A-4. Tensile fiber stresses due to bending under seismic forces may be reduced by the full direct axial stress due to vertical dead loads. (g) URM walls found to be deficient may be permitted to remain in place provided that they are anchored as required for veneer by Section 3006 of the 1985 Edition of the UBC. (h) Wood shear walls shall not be permitted to resist seismic forces imparted by concrete or masonry in buildings over two ( 2) stories in height. 17 2004 ~- ~ .'------ .^~,._.. ~,-..~~~.