7/27/2019 Grating Design

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Design Nomenclature for grating

Thickness of reactangular Bearing Bar(b) = 5 mm

Depth of Bearing Bar(d) = 30 mm

= 30 mm

Number of Bearing Bar per meter grating width (K) = 33 nos

Allowable yield stress for SS316L grating (F) = 170 N/mm2= 170000 KN/m2

Modulus of Elesticity (E) = 200000 N/mm2

= 200000000 KN/m2

= 0.00002475 m3

= 3.7125E-07 m4

Maximum Unstiffening Span length (L) = 1 m

= 4.2075 KN-m

Design For Load case 1 - Concentrated Load at Center

= 16.83 KN

= 4.5 KN

= 1.263E-03 mtr

= 1.26 mm

Design For Case 2 - Uniform Distributed Load over 1m^2 span

Maximum Bending Moment (Mw) = wl^2 / 8

= 33.66 KN/m2

= 3.6 KN/m2

= 6.3131E-04 mtr

= 0.63 mm

Maximum bending deflection due to actual uniform load

(DL) = 5PL^4 / 384EI

So Actual laod P(actual) < Max.Allowable load , so grating are safe in Bending as per

Table 1 of SAES-M-001

So Actual laod P(actual) < Max.Allowable load , so grating are safe in Bending as per

Table 1 of SAES-M-001

So maximum allowable uniform load on grating per meter sq. w=

[(Mw*8)/l^2 ]/l

Actual concentrated load on grating are (P) actual

Maximum bending deflection due to actual concentrated load (DL)

= PL^3 / 48EI

Actual Distributed load on grating are (P) actual per meter sq.

Center to center distance Between Bearing Bar in welded & press

locked grating (Aw)

Section Modulus of grating per meter width (Sw) = Kbd^2/6

Moment of Interia of garing per meter width (Iw) = Kbd^3/12

Maximum Bending Moment for grating per meter of width(Mw)=F*Sw

so Maximum allowable concentrated load on grating per meter(P) =

4 Mw / L

Maximum Bending Moment (Mw) = PL/4