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ORDINANCE NO. NS-1673 PAGE THIRTEEN Design stresses shall be related to test results obtained as noted in Table G. Intermediate values below the maximum may be interpolated. TABLE G ALLOWABLE SHEAR STRESS FOR TESTED UNREINFORCED MASONRY WALLS Eighty percent by test results in psi not less than Average test results cores in psi Seismic in-plane shear based on gross area 30 plus axial stress 40 plus axial stress 50 plus axial stress 100 plus axial stress or more 20 26.7 33.3 67 or more -si (1) 3 ~ . (1) 10 psi maximum(1) FOOTNOTES: (1) Allowable shear stress may be increased by addition of ten (10) per cent of the axial stress due to the weight of the wall directly above. (2) DESIGN COMPRESSION AND TENSION VALUES. Design compressive stresses of analysis specified in this section shall be one hundred (100) psi. Design tension values for unreinforced masonry shall be assumed equal to zero. (h) TESTING OF ROD ANCHORS. Five percent (5%) of the existing rod anchors utilized as all or part of required wall anchors shall be tested in pullout by an approved testing laboratory. The minimum number tested shall be four (4) per floor, with two (2) tests at walls with joists framing into the wall and two (2) tests at walls with joists parallel to the wall. The test apparatus shall be supported on the masonry wall at a minimum distance of the wall thickness from the anchor tested. The rod anchor shall be given a preload of 300 lbs. prior to'establishing a datum for recording elongation. The tension test load reported shall be recorded at one-eighth (1/Sth) inch relative movement of the anchor and the adjacent masonry surface. Results of all tests shall be reported. The allowable resistance value of existing anchors shall be forty percent (40%) of the average of the reported test loads.