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1 INTRODUCTION Engineered design of concrete masonry uses sectionSURSHUWLHV WR GHWHUPLQH VWUHQJWK VWLIIQHVV DQG GH HFWLRQ characteristics. These design philosophies are summa-rized inAllowable Stress Design of Concrete Masonry,Strength Design of Concrete Masonry andPost-Tensioned Concrete Masonry Wall Design(refs. 1, 2, 3).SECTION PROPERTIES Tables 1 through 13 summarize section propertiesof grouted and ungrouted 4-, 6-, 8-, 10-, 12-, 14- and16-in. (102-, 152-, 203-, 254-, 305-, 356- and 406-mm) wide concrete masonry walls, based on:x standard unit dimensions are based on the mini-mum face shell and web thickness requirements of6 WDQGDUG 6 SHFL FDWLRQ IRU /RDGEHDULQJ &RQFUHWH Masonry Units, ASTM C 90-06 (ref. 4) as shownin Figure 1, except as noted in Tables 8 through that prior to ASTM C 90-06, two minimumface shell thicknesses for units 10-in.

2 (254-mm)DQG ZLGHU ZHUH VSHFL HG :LWK WKH LQWURGXFWLRQ of ASTM C 90-06, the two face shell thicknesseswere replaced with one minimum thickness require-ment (11/4 in. (32 mm)). See Reference 5 for furtherinformation. Tables 10 through 13 can be used forsection properties of units complying with previouseditions of ASTM C the nominal face dimensions of all units are 16 by 8 in. high (406 by 203 mm),x all mortar joints are3/8in. ( mm) thick,x all mortar joints are the same depth as the thicknessof the face shell or web on which they are placed,x for ungrouted and partially grouted masonry, allunits have a symmetrical cross-section, square endsand two cores (with the exception of architecturalfeatures such as scores, ribs and split surfaces).Note that the section properties listed can be con-Keywords:concrete masonry walls, engineereddesign, gross area, moment of inertia, net area,radius of gyration, reinforced concrete masonry,reinforced properties, section modulus, sectionproperties, structural propertiesSECTION PROPERTIES OF CONCRETE MASONRY WALLSTEK 14-1B 2007 National Concrete Masonry Association (replaces TEK 14-1A)National Concrete Masonry Associationan information series from the national authority on concrete masonry technologyTEK 14-1 BStructural (2007) ncma TEK)LJXUH 6 SHFL HG %ORFN 'LPHQVLRQV DQG 0 LQLPXP )DFH 6 KHOO DQG :HE 7 KLFNQHVVHV UHI 1558 in.

3 (397 mm)358 in.(92 mm)34 in. (19 mm)758 in.(194 mm)1558 in.(397 mm)114 in.(32 mm)958 in.(244 mm)1158 in.(295 mm)1558 in.(397 mm)1358 in.(346 mm)1558 in.(397 mm) LQ PP EORFN LQ PP EORFN LQ PP EORFN LQ PP EORFN LQ PP EORFN1558 in.(397 mm) LQ PP EORFN1558 in.(397 mm)1 in.(25 mm)1 in.(25 mm)558 in.(143 mm)34 in.(19 mm)34 in.(19 mm)114 mm) LQ PP EORFN1558 in.(397 mm)1558 in.(397 mm)114 in.(32 mm)114 in.(32 mm)114 in.(32 mm)1 in. (25 mm)1 in. (25 mm)118 in. (29 mm)118 in. (29 mm)118 in. (29 mm)118 in. (29 mm) 6 LQJOH RSHQ HQG RU 'RXEOH RSHQ HQG RU $ EORFN + EORFN)LJXUH 2 SHQ (QG 8 QLWV servatively applied to open-end units (see Figure 2) that areeither partially grouted or solid grouted, since by code thecells with the open end must be grouted. The tables include both net and average properties. Netsection properties (An, InandSn) are calculated based on theminimum net cross-sectional area of an assemblage.

4 Thesevalues are related to the critical section when determiningstresses due to an applied load (refs. 6, 7). Average sectionproperties (Aavg,Iavg,Savgandravg) correspond to an averagecross-sectional area of an assemblage, and are used to determineVWLIIQHVV RU GH HFWLRQ GXH WR DSSOLHG ORDGLQJ UHIV The net and average horizontal section properties arelisted in Tables 1a, 2a, etc., while vertical section propertiesare listed in Tables 1b, 2b, etc. For vertically spanning walls,horizontal section properties are calculated along a horizontalaxis parallel to the plane of the masonry (axis X-X in Figure3). For horizontally spanning walls, vertical section propertiesare calculated along a vertical axis parallel to the plane of themasonry (axis Y-Y in Figure 3). In addition to section properties based on the standardunit dimensions shown in Figure 1, Tables 8 and 9 list sectionproperties of walls constructed using 8-in.

5 (203-mm) units withWKLFNHQHG IDFH VKHOOV 7 KHVH XQLWV DUH RIWHQ VSHFL HG WR DFKLHYH KLJKHU UH UDWLQJV 7 DEOH OLVWV VHFWLRQ SURSHUWLHV RI ZDOOV constructed using 10-in. (254-mm) units with 13/8in. (35 mm)face shells, the minimum required prior to ASTM , Tables 11, 12 and 13 list section properties of wallsconstructed using 12-, 14- and 16-in. (305-, 356- and 406-mm)units, respectively, with 11/2in. (38 mm) face LQFK PP 6 LQJOH :\WKH :DOOV /4 LQ PP )DFH 6 KHOOV VWDQGDUG C D +RUL]RQWDO 6 HFWLRQ 3 URSHUWLHV 0 DVRQU\ 6 SDQQLQJ 9 HUWLFDOO\ Grout Mortar Net cross-sectional propertiesA Average cross-sectional propertiesBUnit spacing (in.) bedding An( )In( )Sn( )Aavg( )Iavg( )Savg( )ravg(in.)Hollow No grout Face shell No grout Full solid/solidly grouted Full E 9 HUWLFDO 6 HFWLRQ 3 URSHUWLHV 0 DVRQU\ 6 SDQQLQJ +RUL]

6 RQWDOO\ Hollow No grout Face shell No grout Full solid/solidly grouted Full LQFK PP 6 LQJOH :\WKH :DOOV LQ PP )DFH 6 KHOOV VWDQGDUG D +RUL]RQWDO 6 HFWLRQ 3 URSHUWLHV 0 DVRQU\ 6 SDQQLQJ 9 HUWLFDOO\ Grout Mortar Net cross-sectional propertiesA Average cross-sectional propertiesBUnit spacing (in.) bedding An( )In( )Sn( )Aavg( )Iavg( )Savg( )ravg(in.)Hollow No grout Face shell No grout Full solid/solidly grouted Full 16 Face shell 24 Face shell 32 Face shell 40 Face shell

7 48 Face shell 72 Face shell 96 Face shell 120 Face shell E 9 HUWLFDO 6 HFWLRQ 3 URSHUWLHV 0 DVRQU\ 6 SDQQLQJ +RUL]RQWDOO\ Hollow No grout Face shell No grout Full solid/solidly grouted Full 16 Face shell 24 Face shell 32 Face shell 40 Face shell

8 48 Face shell 96 Face shell 120 Face shell x = mm&219(56,216 x 2,117 = mm2 x 53,763 = mm3 x 1,365,588 = mm4/mFOOTNOTES:A Net cross-sectional properties determined from a vertical plane that coincides with the face shells of the units. Net cross-sectional properties are to be used for determining stress and strain resulting from the application of Average cross-sectional properties determined from two vertical planes calculated as the average of the net and solid proper-WLHV $YHUDJH FURVV VHFWLRQDO SURSHUWLHV DUH WR EH XVHG IRU GHWHUPLQLQJ VWLIIQHVV DQG GH HFWLRQ RI DQ HOHPHQW C %HFDXVH RI WKH VPDOO FRUH VL]H DQG UHVXOWLQJ GLI FXOW\ FRQVROLGDWLQJ JURXW LQ PP XQLWV DUH UDUHO\ JURXWHG 7 DEOH LQFK PP 6 LQJOH :\WKH :DOOV 1/4 LQ PP )DFH 6 KHOOV VWDQGDUG D +RUL]RQWDO 6 HFWLRQ 3 URSHUWLHV 0 DVRQU\ 6 SDQQLQJ 9 HUWLFDOO\ Grout Mortar Net cross-sectional propertiesA Average cross-sectional propertiesBUnit spacing (in.)

9 Bedding An( )In( )Sn( )Aavg( )Iavg( )Savg( )ravg(in.)Hollow No grout Face shell No grout Full solid/solidly grouted Full 16 Face shell 24 Face shell 32 Face shell 40 Face shell

10 48 Face shell 72 Face shell 96 Face shell 120 Face shell E 9 HUWLFDO 6 HFWLRQ 3 URSHUWLHV 0 DVRQU\ 6 SDQQLQJ +RUL]RQWDOO\ Hollow No grout Face shell No grout Full solid/solidly grouted Full 16 Face shell 24 Face shell 32 Face shell 40 Face shell