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<br />, inWJ~~ load lll1ensJty IlIld e.rosjao c.haracl.e.ristics of uopc
<br />. MlU.cn aI
<br />
<br />18054Footings shall be designed an COnstructed In
<br />AJloWabIe bearinB ~acity of the soil is not exC<<ded, and
<br />fhaJ diffm:ntW settlement i3 minimizc<:l, The minimum
<br />Width of f()(){ing! ~I be 12 inches (305 mm)
<br />
<br />~()otmgs in IiTellS with expansive soils shall be designed
<br />In l1Ccordance with the provisions of Sectioo 1805,8.
<br />
<br />] 805,4./1, J Dtsign loads, Footings shall ~ designed for
<br />the ~ lInlll varable effectJ due to the oombinations of
<br />lo!lds spcciijed in Section 1605.3. The dead load s.halJ in.
<br />clued the weight of foundatioos" footings and overlying
<br />5lJ Reduced Uve loads, ~ spcctned in Section 1607,9.
<br />Are pettnjtted to be used in designina footing!,
<br />
<br />1805.4 12 Vibratory loads, Where machinery opent-
<br />tlOOS or other vibnltiorn an: l11Insmitted through the:
<br />foundation, COOS idcratioo &h aI I be aiven in the f oot.ing
<br />design to prtYau dc:aimcntaJ disturbances of the soil,
<br />
<br />I W5.4.1 Concrete footings., The deaign, matcriala and c0n-
<br />struction of calcrete footinp shall comply with SectiOf13
<br />lW54.1,1 through 180504.2.6 and the provisiOO3 ofOlap-
<br />ta 18Oj.42,
<br />
<br />Exception; When 8 specific design iJ 00( provided, c0n-
<br />Crete footings supporting walls of light-framt coostruc-
<br />lioo an: perrnjned to be designed in accordance with
<br />Table I W5.4.1
<br />
<br />I W5 ,4.1, J Concrete strenglb. Coocrete in fClOtirJp
<br />Shall have 8 spcoificd COInpre8aive JtrcDgth (f c) of 001
<br />Less than 2,500 pounds per 5Quare inch (PSi)(J 7 237 kPB)
<br />Al 28 days
<br />
<br />18054.1.1 R~ed,
<br />
<br />SOILS AND FOUNDAA !fUi{\
<br />
<br />J 805,4.2 ,3 P1ain CODCTde footi.nss, The edge UlJ c.J.: Des..\
<br />Of plain COOCrete footing3 supporting walls of OthCl UlilIl
<br />Light-frame corultrudion &haLl 001 be less thaJ 8 inchn
<br />(203 mm) where placed On soil.
<br />Exception: For plain CQrlcrete footing.:; supPonlnr
<br />Group R-3 occupanci~ /he edi~ thicbJ~ is perm II ,
<br />led to be 6 inches () 52 rnm), p r,:,... idc.d that the f ()(){ I n g
<br />Does oot cxteno bcyood a diSUncc grearcr that the
<br />Thi~ of the foot.in! \..ll eithCT ~idc of the 3UPJ>O<lc,j
<br />Wall.
<br />1805.4 .2.4 P)acem~t of Ct:lIlcret.e Cooo-ett fooongs
<br />Shall DOt be placed thtoogb W14'.f Wlless II tremJe or OUltl
<br />
<br />method approved by the building Anew is used, Whc rc
<br />pieced under or in the preseoce of water" the concrete
<br />shall be deposited by approved means to CJ1Sllrt mirll'
<br />mwn segregation of the mix and negligible turbulence ul
<br />the water,
<br />
<br />1805,4.2,5 Protectioo of concrete, u:>ncr-ett footings
<br />shall be protected from freezing during depotiiting IInd f(}i
<br />a period of not Jess than five days thereaftCf. WB1cr shall
<br />Not be allowed to flow through the deposited COI1CT'eU
<br />
<br />I WS ,4.2.6 Forming of c.oocrcte, Concrete footingB an
<br />permitted to be east againlt the earth wbert, in the opin-
<br />ion of the buildin& official, soil conditiorn do 001 f'CqUlIc
<br />furm1og. Where forming b requ1n:d, h sIla1! be In IICCOr,
<br />dance with Olapter 6 of ACl 318.
<br />
<br />1805.4.3 Masonry-unit footings, The design. matcriaJs
<br />and construction of mas.onry-unit fQ.oting.s shall comply
<br />with Sectiow J805.4.3,lllrld 18M.4.3,2.11Dd the proVISIOns
<br />Of Chapter 21,
<br />
<br />Except.ioo: Where . specific dc6ign it 001 providod., ma-
<br />sonry-unit footings supporting WIllls of Jight-fuune con,
<br />Struction are permitted to b designed in IICCOIdancc with
<br />Table 1~.4.2.
<br />
<br />1805.43.1 DimeIWoo., Masaory-unit footing ahalJ be
<br />laid in Type M Of S Dlortar complying with Section
<br />
<br />TABLE 1805,4.2
<br />FOOTINGS SUPPORTING WALLS OF LIGHT-FRAME CONSTRUcnONab,c.d
<br />
<br /> WIDTH OF I THlCKNEss OF
<br />NUMBER OF FLOORS FOOTINGS FOOTING
<br />SuPPORTED BY TIiE FOOTINGS. (inches) (inches )
<br />I 12 6
<br />2 15 6 I
<br /> I
<br />3 18 8 J
<br />
<br />FOl S J I inch == 25,4 mm, I foo( ., 304,8 ffiJD,
<br />a Depth offootingJ shall be in accordaocc with Sectioo 18052,
<br />b The ground under the fiOOl is perm.itte<l to be excavated to the elevatioo of the top of the footing.
<br />c Interior~ walls arc pc:nniu.ed to be IUpported by iJo1at.ed footings, The footing width end Ic:ngth &haJJ be t\>.'lCC
<br />the width shown in this table, and footinp shall be spaced not more than 6 Feet on center.
<br />d F 0( thickness offoundatioo waJ Is, see Sectioo 1805.5,
<br />c Footings are permitted to support . roof in addition to the stipulated nwnber of t:loon, Footings sllppOrtmg root otll \
<br />ShA1.I be as required fOl' supporting ODe floor.
<br />f Plain coocrcte footings fO( Group R - 3 ocalp8.nci~ are penn itt.ed to be 6 inches thick
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