Cantilever Masonry Wall Example.pdf

DESIGN EXAMPLE

The following design example briefly illustrates some of the basic steps used in the allowable stress design of a reinforced concrete masonry cantilever retaining wall. Example: Design the reinforced concrete masonry cantilever retaining wall shown in Figure 2. Assume level backfill, no surcharge or seismic loading, active earth pressure and masonry laid in running bond. The coefficient of friction between betwe en the footi ng and found ation soil,k soil, k 1, is 0.25, and the allowable soil bearing pressure is 2,000 psf (95.8 kPa) (ref. 7). a. Design criteria: Wall thickness = 12 in. (305 mm) f' m = 1,500 psi (10.3 MPa)

T

8 ft 8 in. (2.5 m)

b. Rankine active earth pressure γ (H + t) 2 K a P a = 1/2 γ (H where K where K a = tan2 (45 - φ /2) = tan2 (45 - 30/2) = 0.33 P a = 1/2 (120) (9.67)2 (0.33) = 1,851 lb/ft (27 kN/m)

Overturning moment M = P a (height/3) = (1,851 lb/ft)(9.67 ft/3) = 5,966 ft-lb/ft (27 kN.m/m) c. Resisting moment (about toe of footing) Component weights: maso ma sonr nry: y: (0.97)(8.67 (0.97)(8.67 ft)(130 ft)(130 pcf) = 1,093 1,093 lb/ft (16 kN/m) eart ea rth: h: (2.69)(8.67 (2.69)(8.67 ft)(120 ft)(120 pcf) = 2,799 2,799 lb/ft (41 kN/m) foot fo otin ing: g: (1.0)(5.33 (1.0)(5.33ft)(150 ft)(150 pcf) pcf) =800 lb/ft (12 kN/m) kN/m)

Weight (lb/ft) masonry: 1,093 ear th: 2,799 foo ting : 800 4,692 Tota Totall res resis isti ting ng mome moment nt Overt erturnin ning moment ent

x x x x

Arm (ft) = Moment (ft-lb/ft) 2.67 = 2,918 3.98 = 11,140 2.67 = 2,136 16,194 16,19 6,194 4 ft-lb t-lb/f /ftt - 5,966 ft-lb/ft 10,228 ft-lb/ft (45.5 kN.m/m)

d. Check factors of safety (F.S.) F.S. (overturning) (overturning) = total resisting moment about toe/overturning moment = 14,670/5,966 = 2.4 > 1.5 O.K. TEK 15-7B National Concrete Masonry Association

γ = 120 pcf (1,922 kg/m 3) φ = 3 0°

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t p B

Assumed weights: Reinforced masonry: 130 pcf (2,082 kg/m3) (solid grout to increase overturning and sliding resistance) Reinforced concrete: 150 pcf (2,402 kg/m3) Required factors of safety (ref. 7) F.S. (overturning) = 1.5 F.S. (sliding) = 1.5

Trial dimensions: T = 11.625 in. (0.29 m) t = 1 ft (0.30 m) B = 5 ft 4 in. (1.63 m) a =1 ft 8 in. (0.51 m)

x

Figure 2—Reinforced Cantilever Retaining Wall Design Example

F .S .( slidin sli ding g ) =

(ΣW )k 1 + P p P a

P p = 1/2 D (soil D (soil lateral bearing pressure) set D set D = t = 1.0 ft (0.30 m) soil lateral bearing pressure = 150 psf/ft below grade (ref. 7)

F . S .( sliding slidin g ) =

(4,692 692 lb / ft )(0.25 ) + 12 (1)(150 150 psf / ft ) 1,851 851 lb / ft

= 1,248/1,851 = 0.67 < 1.5 e.

N.G. N.G.,, need need key key

Pres Presssure ure on foot footin ing g Location of resultant force, x = (10,228 ft-lb/ft)/(4,692 lb/ft) = 2.18 2.18 ft (0.6 (0.6 m) m) (resultant (result ant falls in middle 1/3 of base) e = (5.33 ft/2) - 2.18 = 0.48 ft (0.15 m)

W Mc W 6We ± = ± A I bd bd 2 4,692 692 lb / ft 6(4,692 692 lb / ft )(0 .48 ft ) ± p = (1 ft )(5. 33 ft ) (1 ft )(5.33 ft ) 2 p =

p = p = 880 + 476 = 404 psf (19.3 kPa) and 1,356 psf (64.9 kPa) < 2,000 psf (95.8 kPa) O.K. f. Determine size of key Passive lateral soil resistance = 150 psf/ft of depth and may be increased increa sed 150 psf for each additi onal foot of depth to a maximum of 15 times the designated value (ref. 7). The average soil pressure under the footing is:1/2 (1,356 + 404) = 880 psf (42.1 kPa). Equivalent soil depth: 880 psf/120 pcf = 7.33 ft (2.23 m) P p = (150 psf/ft)(7.33 ft) = 1,100 psf (52.7 kPa)

For F.S. (sliding) = 1.5, the required total passive soil resistance is: 1.5(1,851 lb/ft) = 2,776 lb/ft (41 kN/m) The shear key must provide for this value minus the frictional resistance: 2,776 - 1,248 = 1,528 lb/ft (22 kN/m). Depth of shear key = (1,528 lb/ft)/(1,100 psf) = 1.39 ft (0.42 m), try 1.33 ft (0.41 m). At 1.33 ft, lateral resistance = (1,100 psf) + (150 psf/ft)(1.33 ft) = 1,300 lb/ft (19 kN/m) Depth = (1,528 lb/ft)/[ 1/2 (1,100 + 1,300)] = 1.27 ft (0.39 m) < 1.33 ft (0.41 m) O.K.

reinforcing steel based on the equivalent fluid weight of soil, wall thickness, and wall height. For this example, the equivalent fluid weight = ( K a)(γ ) = 0.33 x 120 = 40 pcf (6.2 kN/m3). Using allowable stress design (Table 1) and the cons ervative equivalent fluid weight of soil of 45 pcf (7.1 kN/m3), this wall requires No. 6 bars at 16 in. o.c. (M #19 at 406 mm o.c.). Using strength design (Table 2), this wall requires No. 5 bars at 16 in. o.c. (M #16 at 406 mm o.c.). h. Design of footing The design of the reinforced concrete footing and key should conform to American Concrete Institute requirements. For guidance, see ACI Standard 318 (ref. 2) or reinfo rced concrete design handbooks.

g. Design of masonry Tables 1 and 2 can be used to estimate the required Table 1—Allowable Stress Design: Vertical Reinforcement for Cantilever Retaining Wallsa, b

CONSTRUCTION

10 (254)

4.0 (1.2) 4.7 (1.4) 5.3 (1.6) 6.0 (1.8) 6.7 (2.0) 7.3 (2.2) 8.0 (2.4)

Materials and construction practices should comply with Reinforcement size & spacing for applicable requirements of Specification for Masonry Strucequivalent fluid weight of soil, lb/ft2/ft (kN/m2/m), of: Table 2—Strength Design: Vertical Reinforcement for 30 (4.7) 45 (7.1) 60 (9.4) Cantilever Retaining Wallsa, b c c No.4 @ 88 in. No.4 @ 56 in. No.4 @ 40 in. No.4 @ 48 in. No.4 @ 32 in. No.4 @ 16 in. Reinforcement size & spacing for No.4 @ 32 in. No.4 @ 16 in. No.5 @ 24 in. Wall Wall equivalent fluid weight of soil, No.4 @ 16 in. No.5 @ 16 in. No.7 @ 16 in. thickness, height, lb/ft2/ft (kN/m2/m), of: No.4 @ 16 in. No.7 @ 16 in. No.9 @ 8 in. in. (mm) H , ft (m) 30 (4.7) 45 (7.1) 60 (9.4) 8 (203) 4.0 (1.2) No.4 @ 120 in. No.4 @ 96 in. No.4 @ 64 in. No.4 @ 120 in.c No.4 @ 88 in.c No.4 @ 64 in.c 4.7 (1.4) No.4 @ 88 in. No.4 @ 56 in. No.4 @ 40 in. No.4 @ 88 in.c No.4 @ 48 in. No.4 @ 32 in. 5.3 (1.6) No.4 @ 56 in. No.4 @ 32 in. No.4 @ 24 in. No.4 @ 56 in. No.4 @ 32 in. No.4 @ 16 in. 6.0 (1.8) No.4 @ 32 in. No.4 @ 24 in. No.4 @ 16 in. No.4 @ 32 in. No.4 @ 16 in. No.5 @ 24 in. 6.7 (2.0) No.4 @ 24 in. No.4 @ 16 in. No.5 @ 16 in. No.4 @ 24 in. No.5 @ 16 in. No.5 @ 16 in. No.4 @ 16 in. No.5 @ 16 in. No.7 @ 16 in. 10 (254) 4.0 (1.2) No.4 @ 120 in. No.4 @ 120 in. No.4 @ 104 in. No.5 @ 16 in. No.7 @ 16 in. No.8 @ 8 in. 4.7 (1.4) No.4 @ 120 in. No.4 @ 88 in. No.4 @ 56 in.

12 (305)

4.0 (1.2) 4.7 (1.4) 5.3 (1.6) 6.0 (1.8) 6.7 (2.0) 7.3 (2.2) 8.0 (2.4) 8.7 (2.7) 9.3 (2.8)

No.4 @ 120 in.c No.4 @ 120 in.c No.4 @ 96 in.c No.4@ 120 in.c No.4 @ 72 in. No.4 @ 48 in. No.4 @ 80 in.c No.4 @ 48 in. No.4 @ 32 in. No.4 @ 48 in. No.4 @ 24 in. No.4 @ 16 in. No.4 @ 32 in. No.4 @ 16 in. No.5 @ 16 in. No.4 @ 24 in. No.5 @ 16 in. No.5 @ 16 in. 12 (305) No.4 @ 16 in. No.5 @ 16 in. No.6 @ 16 in. No.5 @ 16 in. No.6 @ 16 in. No.8 @ 16 in. No.5 @ 16 in. No.7 @ 16 in. No.8 @ 8 in.

Wall Wall thickness, height, in. (mm) H , ft (m) 8 (203) 4.0 (1.2) 4.7 (1.4) 5.3 (1.6) 6.0 (1.8) 6.7 (2.0)

a

b

c

The reinforcement listed is designed to resist soil loads only. Other conditions, such as surcharges or seismic loads, also need to be considered where applicable. based on: fully grouted masonry ; f' m = 1500 psi (10.3 MPa); d = 5 in., 7 in. and 9 in. (127, 178, and 229 mm) for wall thicknesses of 8, 10, and 12 in. (203, 254, and 305 mm), respectively; level backfill to top of wall The specified reinforcement spac ing is greater than six times the wall thickness. Prudent engineering practice dictates that stresses in the unreinforced masonry spanning betwe en the reinforcing be designed meet Building Code ReTEK 15-7Bbars National ConcretetoMasonry Association quirements for Masonry Structures Section 2.2.3.2 (ref. 1).

a

b

5.3 (1.6) 6.0 (1.8) 6.7 (2.0) 7.3 (2.2) 8.0 (2.4)

No.4 @ 96 in. No.4 @ 56 in. No.4 @ 40 in. No.4 @ 24 in. No.4 @ 16 in.



4.0 (1.2) 4.7 (1.4) 5.3 (1.6) 6.0 (1.8) 6.7 (2.0) 7.3 (2.2) 8.0 (2.4) 8.7 (2.7) 9.3 (2.8)

No.4 @ 120 in. No.4 @ 120 in. No.4 @ 120 in. No.4 @ 120 in. No.4 @ 120 in. No.4 @ 88 in. No.4 @ 120 in. No.4 @ 80 in. No.4 @ 56 in. No.4 @ 88 in. No.4 @ 48 in. No.4 @ 32 in. No.4 @ 56 in. No.4 @ 32 in. No.4 @ 24 in. No.4 @ 40 in. No.4 @ 24 in. No.4 @ 16 in. No.4 @ 24 in. No.4 @ 16 in. No.5 @ 16 in. No.4 @ 16 in. No.5 @ 16 in. No.5 @ 16 in. No.4 @ 16 in. No.5 @ 16 in. No.6 @ 16 in.

The reinforcement listed is designed to resist soil loads only. Other conditions, such as surcharges or seismic loads, also need to be considered where applicable. based on: fully grout ed masonry; f' m = 1500 psi (10.3 MPa); d = 5 in., 7 in. and 9 in. (127, 178, and 229 mm) for wall thicknesses of 8, 10, and 12 in. (203, 254, and 305 mm), respectively; level backfill to top of wall

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Verification Example

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Engineer: Javier Encinas, PE Descrip: ASDIP Retain 3.0.0

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kft

ToeLength............................

ft

Stem'ertical(Live*...............

kft

HeelLength...........................

ft

'erticalLoa"+ccentricit,.....

in

SoilCover@Toe..................

ft

-in"Loa"onStem...............

sf

BackfillHeight.......................

ft

-in"HeightfromTo...........

ft

BackfillSloe!ngle..............

"eg

#ofRowsofBlocks..............

-all taer

$

/./// ra"

Backfill sloe

/./ 0 1.23  24/ 5 /./// ra"

6nternal friction -all9soil friction

1/./ 0 1.23  24/ 5 /.783 ra" /.783  8 5 /.8:8 ra"

Seismic angle

aTan (/  (2 9 /** 5 /./// ra"

Footing length

2.:; < 28./  28 < 8.:; 5 7.13 ft

Height for Sta=ilit,

/.// < 4.:; < 28./  28 5 >.:; ft

+arthress%retheor,5 Rankine!ctive

Moist"ensit,5 28/cf

!ctive coefficient !ctive ress%re

Sat%rate""ensit,521/cf 5 /.11

/.11 0 28/./ 5 3/./ sfft of height

9Forsta=ilit,anal,sis(non9seismic* !ctive force

/.11 0 28/./ 0 >.:;?  8 5 2.> kft 2.> 0 Cos (/.///* 5 2.> kft 

2.> 0 Sin (/.///* 5 /./ kft

-aterforce &w5(/.110(21/./9:8.3928/./*<:8.3*0(/.//<28./28*?85/./kft 9Forstem"esign(non9seismic* !ctive force

/.11 0 28/./ 0 4.:;?  8 5 2.7 kft 2.7 0 Cos (/.///* 5 2.7 kft 

2.7 0 Sin (/.///* 5 /./ kft

-aterforce &w5(/.110(21/./9:8.3928/./*<:8.3*0/.//?85/./kft

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Page # ___


6!"!

%$Cantilever Masonry Example www.asdipsoft.com


!ctive seismic coeff.

5 /.1/

9Forsta=ilit,anal,sis(seismic* Seismic force

/.1/ 0 28/./ 0 >.:;?  8 0 (2 9 /./ * 5 2.; kft 2.;0Cos(/.8:8</.///*52.:kft 2.;0Sin(/.8:8</.///*5/.3kft

-aterforce &we5/.//0(21/./928/./*0(/.//<28./28*?85/./kft 9Forstem"esign(seismic* Seismic force

/.1/ 0 28/./ 0 4.:;?  8 5 2.3 kft 2.30Cos(/.8:8</.///*52.1kft 2.30Sin(/.8:8</.///*5/.3kft

-aterforce &we5/.//0(21/./928/./*0/.//?85/./kft

Backfill 5 !rm 5

2./ 0 2.> 5 2.> kft >.:;  1 5 1.88 ft

Moment 5 2.> 0 1.88 5 :./ k9ftft

-ater ta=le 5

2./ 0 /./ 5 /./ kft

!rm 5

(/.// < 28./  28*  1 5 /.11 ft

S%rcharge 5 !rm 5

Moment 5 /./ 0 /.11 5 /./ k9ftft

2./ 0 /.11 0 /./ 0 >.:; 5 /./ kft >.:;  8 5 3.41 ft

Moment 5 /./ 0 3.41 5 /./ k9ftft

Stri loa" 5

/./ kft

!rm 5 3.11 ft

Moment 5 /./ 0 3.11 5 /./ k9ftft

-in" loa" 5

2./ 0 /./ 0 7.// 5 /./ kft

!rm 5

28./  28 < 4.:; 9 7.//  8 5 ;.2; ft

Moment5/./0;.2;5/./k9ftft Backfill seismic 5 !rm 5

/./ 0 (2.: 9 2.:* 5 /./ kft /.: 0 >.:; 5 7.4/ ft

-ater seismic 5 !rm 5 -all seismic 5

Moment 5 /./ 0 7.4/ 5 /./ k9ftft /./ 0 /./ 5 /./ kft

(/.// < 28./  28*  1 5 /.11 ft

Moment 5 /./ 0 /.11 5 /./ k9ftft

/./ 0 (2./ < /.4* 0 /.// 5 /./ kft

Moment5 5/./0(2./0(28./28<4.:;8*</.4028./288*0/.//5/./k9ftft Hor.res%ltantRh52.></./</./</./</./</./</./</./52.>kft vert%rningmomentTM5:./</./</./</./</./</./</./</./5:./k9ftft !rm of hor. res%ltant 5

:./  2.> 5 1.88 ft

!

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Cantilever Masonry Example


Stem weight

6!"!$% www.asdipsoft.com

2./ 0 4.:; 0 /.28 5 2.2 kft

!rm 5

2.:; < 28./  28  8 5 8.2; ft

Stem taer

Moment 5 2.2 0 8.2; 5 8.1 k9ftft 2./ 0 (28./ 9 28./*  28 0 4.:;  8 0 /.28 5 /./ kft

!rm 5

2.:; < 28./  28  8 5 /.// ft

Moment5/./0/.//5/./k9ftft CMUstematto5 /./kft !rm 5

2.:; < 4./  28  8 5 /.// ft

Moment5/./0/.//5/./k9ftft Ftg. weight

2./ 0 7.13 0 28./  28 0 /.27 5 /.4 kft

!rm 5

7.13  8 5 8.:; ft

Moment 5 /.4 0 8.:; 5 8.2 k9ftft

$e, weight

2./ 0 2:.//  28 0 28./  28 0 /.27 5 /.8 kft

!rm 5

2.:; < 28./  28  8 5 8.2; ft

Soil cover 5

Moment 5 /.8 0 8.2; 5 /.3 k9ftft

2./ 0 2.:; 0 /.// 0 28/./ 5 /./ kft

!rm 5

2.:;  8 5 /.43 ft

Moment 5 /./ 0 /.43 5 /./ k9ftft

Stem we"ge 5

2./ 0 (8/./ 9 28./*  28 0 4.:;  8 0 28/./ 5 /./ kft

!rm 5

2.:; < 8/./  28 9 (8/./ 9 28./*  28  1 5 /.// ft

Moment5/./0/.//5/./k9ftft Backfill weight 5 !rm 5

2./ 0 8.:; 0 4.:; 0 28/./ 5 8.4 kft 7.13 9 8.:;  8 5 3./2 ft

Moment 5 8.4 0 3./2 5 22.2 k9ftft

Backfillsloe5 52./08.;0/.//8028/./5/./kft !rm 5

7.13 9 8.:;  1 5 3.37 ft

Moment5/./03.375/./k9ftft -ater 5 !rm 5

2./ 0 8.:; 0 /.// 0 (21/./ 9 28/./* 5 /./ kft 7.13 9 8.:;  8 5 3./2 ft

Seismic &ae9&a 5 !rm 5

/./ 0 (/.3 9 /.3* 5 /./ kft 7.13 ft

Backfill &av 5 !rm 5

Moment 5 /./ 0 3./2 5 /./ k9ftft

Moment 5 /./ 0 7.13 5 /./ k9ftft 2./ 0 /.3 5 /./ kft

7.13 ft

Moment 5 /./ 0 7.13 5 /./ k9ftft

Concentrate" 5 !rm 5

2./ 0 /./ < /./ 0 /./ 5 /./ kft 2.:; < (28./ 9 :./*  28 5 8.2; ft

Moment5/./08.2;5/./k9ftft

&

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Cantilever Masonry Example www.asdipsoft.com


S%rcharge 5 !rm 5

6!"!

%$2./ 0 8.; 0 /./ 5 /./ kft 7.13 9 8.:;  8 5 3./2 ft

Moment5/./03./25/./k9ftft Stri 5

2./ 0 /./ 0 8.:; 5 /./ kft

!rm 5

7.13 9 8.:;  8 5 3./2 ft

'er. res%ltant Rv 5

3.> kft

Resisting moment RM 5

2:./ k9ftft

Moment 5/./ 0 3./2 5 /./ k9ftft

!rm of ver. res%ltant 5

2:./  3.> 5 1.1/ ft

vert%rning ratio 5

2:./  :./ 5 8.::

+ccentricit, 5

9

5

7.13 8

Bearing length 5

9

A 2.7/

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2:./9:./ 3.>

5/.:2ft

Min (7.13 1 0 (7.13  8 9 /.:2** 5 7.13 ft

Toe =earing 5

<

5

Heel =earing 5

9

5

3.> 7.13 3.> 7.13

<

9

:03.>0/.:2 7.13? :03.>0/.:2 7.13?

5 2.7 ksf

 8./ ksf

$

5/.1ksf

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6!"!



&assive coefficient

www.asdipsoft.com

2  /.11 5 1.// ksf

&assive "eth

/.// < (28./ < 2:./*  28 9 /.// 5 8.11 ft

&assive ress%re to 5

1.// 0 28/./ 0 /.// 5 /.// ksf

&assive ress%re =ot 5

1.// 0 28/./ 0 (8.11 < /.//* 5 /.43 ksf

&assive force 5

(/.// < /.43*  8 0 8.11 5 2./ kft

Friction force 5

Ma (/ 3.> 0 /.87* 5 2.8 kft

Sli"ing ratio 5

(2./ < 2.8*  2.> 5 2.2;

Backfill 5

 2.7/

DE

2.: 0 2.7 5 8.3 kft

!rm 5

4.:;  1 5 8.4> ft

-ater ta=le 5

Moment 5 8.3 0 8.4> 5 :.> k9ftft

2.: 0 /./ 5 /./ kft

!rm 5

/.//  1 5 /.// ft

Moment 5 /./ 0 /.// 5 /./ k9ftft

S%rcharge 5 !rm 5

2.: 0 /.11 0 /./ 0 4.:; 5 /./ kft 4.:;  8 5 3.11 ft

Moment 5 /./ 0 3.11 5 /./ k9ftft

Stri loa" 5

/./ kft

!rm 5 3.11 ft

Moment 5 /./ 0 3.11 5 /./ k9ftft

-in" loa" 5

/./ 0 /./ 0 7.// 5 /./ kft

!rm 5

4.:; 9 7.//  8 5 :.2; ft

Backfill seismic 5 !rm 5

Moment 5/./ 0 :.2; 5 /./ k9ftft

2./ 0 (2.1 9 2.1* 5 /./ kft /.: 0 4.:; 5 7.8/ ft

-ater seismic 5 !rm 5

Moment 5 /./ 0 7.8/ 5 /./ k9ftft

2./ 0 /./ 5 /./ kft /.//  1 5 /.// ft

Moment 5 /./ 0 /.// 5 /./ k9ftft

Ma.shear58.3</./</./</./</./</./</./58.3kft Shear at critical section 5

8.3 9 8.3  4.:; 0 4.:  28 5 8.8 kft

Ma.moment5:.></./</./</./</./</./</./5:.>k9ftft :.>  (8.3 0 28./  28* 5 8.4>

3./

MSC1.1.3.2.8

Shearstrength

MSC+G.(1981*

'n5/.4/0Min(3./3./92.;7<8.4>*0233./0(27//*I52/./kft A8.8kft Use#7@2:./in(Backe"ge* De%tral ais

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/.120:/./(/.402.702:./*52./in

2./  /.4 5 2.8 in

 Shell tfs 5 2.7 in (Soli" gro%te"*

Ben"ingstrength

MSC1.1.7.3

Mn5/.>/0/.120:/./0(4.:92./8*2:./54.7k9ftftA:.>k9ftft Hooke" )ev. length at footing 5

$

/./80:/./02///(3///*I0/.//0/.;5/./in 5 28./ 9 1./ 5 >./ in

A /./ in

!C628.7

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Project:



Bearingforce5 /./kft

Page # ___ 6!"!



www.asdipsoft.com

(Deglect=earingress%reforheel"esign*

!rm5 5(8.808.:;?8<(2.798.8*08.:;?:*/./5/.4>ft Moment5 /./0/.4>5/./k9ftft Concrete weight 5 !rm 5

2.3 0 28./  28 0 8.:; 0 /.27 5 /.3 kft

5 8.:;  8 5 2.13 ft

Backfill weight 5 !rm 5

Moment 5/.3 0 2.13 5 /.7 k9ftft 2.3 0 8.:; 0 4.:; 0 28/./ 5 8.7 kft

5 8.:;  8 5 2.13 ft

Moment 5 8.7 0 2.13 5 1.1 k9ftft

Backfillsloe5 52.308.;0/.//8028/./5/./kft !rm 5

8.:; 0 8  1 5 2.;4 ft

-ater 5 !rm 5

Moment 5/./ 0 2.;4 5 /./ k9ftft 2.3 0 8.:; 0 /.// 0 (21/./ 9 28/./* 5 /./ kft

5 8.:;  8 5 2.13 ft

Moment 5 /./ 0 2.13 5 /./ k9ftft

6

Project:


Page # ___


Cantilever Masonry Example


S%rcharge 5 !rm 5

6!"!$% www.asdipsoft.com

2.3 0 8.; 0 /./ 5 /./ kft 5 8.:;  8 5 2.13 ft

Moment 5/./ 0 2.13 5 /./ k9ftft

Stri 5

2.3 0 /./ 0 3.// 5 /./ kft

!rm 5

1.// < 3.//  8 5 /.:; ft

Moment5 /./0/.:;5/./k9ftft Ma.Shear'%5 9/./</.3<8.7</./</./</./</./53.3kft Ma.MomentM%59/./</.7<1.1</./</./</./</./57.>kft Shearstrength

!C6+G.(2291*

'n5/.;7080(3///*I0280>.;522./kft A'%53.3kft Use#7@2:./in

!s 5 /.81 in?ft

$

/.81  (28 0 >.;* 5 /.//8/

Ben"ingstrength

!C62/.8.;

Mn5/.>/0>.;?03./0/./1/0(29/.7>0/./1/*52/./k9ftft AM%57.>k9ftft Cover factor 5

$

Min (8.7 (8./ < /.:1  8 2:./  8*  /.:1* 5 8.7

Straight

!C6+G.(2892*

513/0:/./02///(3///*I0/.402./8.70/.:1523.8in Hooke"

/./80:/./02///(3///*I0/.:10/.;54.1in

)ev. length at toe si"e 5

5 (7.13 9 8.:;*  28 9 8./ 5 1/./ in

)ev. length at heel si"e 5

5 8.:;  28 9 8./ 5 1/./ in A 23.8 i n

Bearing force 5

A 23.8 in

!C628.7 $

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(8.; < 2.4*  8 0 2.:; 5 1.; kft

!rm5 5(2.402.:;?8<(8.;92.4*02.:;?1*1.;5/.4>ft Moment5 1.;0/.4>51.1k9ftft Concrete weight 5 !rm 5

/.> 0 28./  28 0 2.:; 0 /.27 5 /.8 kft

5 2.:;  8 5 /.43 ft

Soil cover 5 !rm 5

Moment 5/.8 0 /.43 5 /.8 k9ftft /.> 0 2.:; 0 /.// 0 28/./ 5 /./ kft

5 2.:;  8 5 /.43 ft

Moment 5 /./ 0 /.43 5 /./ k9ftft

Ma.Shear'%5 1.;9/.89/./51.7kft Shear at crit. section '% 5

1.7 0 (2.:; 9 4.;  28*  2.:; 5 8./ kft

Ma.MomentM%51.19/.89/./51.2kft Shearstrength

!C6+G.(2291*

'n5/.;7080(3///*I02804.;5>.>kft Use#7@2:./in

!s 5 /.81 in?ft

A'%58./kft

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Cover factor 5

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Min (8.7 (1./ < /.:1  8 2:./  8*  /.:1* 5 8.7

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Cantilever Masonry Wall Example.pdf

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