Slab-On-Grade [ B.P.T.T ]

8/18/2019 Slab-On-Grade [ B.P.T.T ]

1/5

DONE BY:A.D CHK BY: A.D

REVISION:

EFERENCE OUTPU

ACI 360R-92

(6-3)

As= cross-sectional area in square inches of steel per lineal foot of slab width

t= thickness of slab in inches

F= the friction factor ( designated μ in Chapter 8)

f s= allowable working stress of the reinforcement (psi)

L= distance in ft between joints

w= dead weight of the slab, psf

L= ft.

t= in.

F= Fig 6.3

F = psi

Fc= psi

Conc. Density = lb/ft3

w= 75 psf.

f s= 30000 psi

(6-3)

Applying the formula ,As= 0.075 in2/ft

using # bars

As/bar = 0.11 in /bar

Spacing Calc :

# 3 bar : s ≤ ( 0.11 in2/bar x 0.08 in

2/ft )

S ax= 17.67 in.

Therefore use, S= in. < 17.67375 in. O.k

SLAB ON GRADE USING THE SUBGRADE DRAG EQUATION

PROJECT NAME:

FACILITIES FOR B.P.T.T AT MAYARO

DATE: MARCH 5th 201

TITLE:SLAB-ON-GRADE DESIGN

CALCULATIONS AND FORMULAS

The subgrade drag equation is frequently used to determine the amount of non-prestressed reinforcement to serve

as shrinkage and temperature reinforcement and to control crack widths for slabs on grade. It does not applywhen prestressing or fibers are used. The reinforcement selected by this equation is not intended to serve as

flexural reinforcement.

12 in/ft x


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REVISION:

EFERENCE OUTPU

PROJECT NAME:


DATE: MARCH 5th 201



Using :

t= in.

F = psi.

Fc= psi.

f s= 40000 psi

Applying the formula ,As= 0.341526 in2

using # bars

As/bar = 0.20 in2/bar

Spacing Calc :

# 4 bar : s ≤ ( 0.20 in2/bar x 0.34 in

2/ft )

S ax= 6.90 in.

Therefore use, S= in. < 6.899914 in. O.k

An alternative procedure for selecting the area of steel for slabs on grade is the equivalent strength procedure.

This procedure equates the cross sectional area of concrete multiplied by the working stress to an equal amount

of reinforcing steel force

SLAB ON GRADE BASED ON BASED ON THE CONCRETE-TO-STEEL STRENGTH RATIO

12 in/ft x


4/5


REVISION:

EFERENCE OUTPU

PROJECT NAME:


DATE: MARCH 5th 201



where:

L = the maximum length (or width), feet

hr = the reinforced slab thickness, inches

fs= the steel yield strength, pounds per square

t, r = in.F = psi.

Fc= psi.

S=

f s= 40000 psi

L= 50.709459 ft.

Use S= ft.

Traverse Joint Spacing

Transverse contraction joint joints in reinforced concrete slabs should not be constructed at intervals of less than

25 feet nor more than 75 feet. Maximum allowable slab width and specifications are given in paragraph 5-7d.Length may be determined from the equation

≤ 75

≤ 75


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REVISION:

EFERENCE OUTPU

PROJECT NAME:


DATE: MARCH 5th 201



L= ft.

t= in.

F= Fig 6.3

F = psi

Fc= psi

Conc. Density = lb/ft3

Min , emp = Fo

Max, emp= Fo

Es= psi

1-layer of #4 @ 12in. c/c spacing B.W

c = 2.5 in.

w = 3/4 in

To be done every 40 ft.

Poured Joint Sealant

Detail 1.0

Control Joint Detail

SUMMARY

t=6in.

See detail.1.0

1in.

1.5 in

Documents

Slab-On-Grade [ B.P.T.T ]