IRCSP13_Design of SlabCulverts.pdf

STRUCTURAL DETAILS OF SLAB CULVERTS (SPAN UP TO 6.00M)

References :: (1) IRC:SP:13-2004 GUIDELINES FOR THE DESIGN OF SMALL BRIDGES AND CULVERTS (First Revision) :: Table 1.1 + Clauses.1.3.1 &13.5.6 + PLATE-5, 8, 9 (2) POCKET BOOK FOR HIGHWAY ENGINEERS (Second revision) :: Chapter 8

Compiled by :-

V. VENKATA NARAYANA DEPUTY EXECUTIVE ENGINEER ROADS & BUILDINGS DEPT. [email protected]

GUIDE LINES, SUGGESSITIONS and DESIGN of SLAB CULVERTS GUIDE LINES and SUGGESSITIONS :1) Number of spans should be 1, 3, 5, 7, 8, 9,10 etc.. (Clause 12.4.3 of IRC:SP:13-2004) In case for Number of spans 2,4 and 6 the Middle pier will be located right in the center of stream and always obstructs the stream flow. Also hard foundation may not be available at shallow depths. 2) IN case of Widening the existing culverts GROUPING can done as shown in parenthesis with CLEAR SPAN. 2Vx1.00m (1Vx2.60m), 3Vx1.00m (1Vx4.20m), 4Vx1.00m(2Vx2.60m) and 6Vx1.00m (2Vx4.20m) 2Vx2.00m (1Vx4.60m), 4Vx2.00m (2Vx4.60m), 6Vx2.00m(3Vx4.60m) . 3) In case of New Culverts H should be 1.50m and above.(Clause 12.5 of IRC:SP:13-2004): For Widening the existing culverts H may be 1.00m (Hence the values are stroked like 1.00). 4) For Clear Spans 1.00m and 2.00m: The design values are as per POCKET BOOK FOR HIGHWAY ENGINEERS (Second revision) :Chapter 8 5) For Effective spans 3.00m, 3.50m, 4.00m, 4.50m, 5.00m, 5.50m and 6.00m : The design values are as perIRC:SP:13-2004

GUIDELINES FOR THE DESIGN OF SMALL BRIDGES

AND CULVERTS (First Revision):Table 1.1, Clauses.1.3.1 PLATE-5, 8, 9. 6) If the design span does not exactly match with the available type design : The details of the next higher span length be used (Clause 1.3.1 of IRC:SP:13-2004). 7) Pier/Abutment cap (Bed block): 300 mm depth with VRCC M20 or VRCC M25 grade concrete (Clause 13.5.6 of IRC:SP:13-2004). 8) Minimum Bearing Capacity of the soil should be 16.50 t/m2 For the abutment and wing wall section up to 4.00m height. (Clause 14.1of IRC:SP:13-2004) 9) MATERIALS :(Chapter 13 of IRC:SP:13-2004) Leveling Course : M15 grade with 40 mm size Course Aggregate. Foundation : M15 grade with 40 mm size Course Aggregate. Substructure : M15 grade with 40 mm size Course Aggregate. Pier/Abutment cap (Bed block) : VRCC M20 or VRCC M25 grade with 20 mm size Course Aggregate. Bearings: Tar paper bearing. Deck Slab : VRCC M20 or VRCC M25 grade with 20 mm size Course Aggregate.

DESIGN:1) Span Length and Number of Spans : (i)For Widening the existing culverts, Span can be ascertained by GROUPING as per S.No.(2) above (ii)For New culvers, Span can ascertained as per Site condition or as per Design. Design Span Length be adjusted as per S.No.(6) above 2) Deck Slab Depth (D1 & D2 or D): For the Designed Span, Deck Slab depth is selected from Table : STRUCTURAL DETAILS OF SLAB CULVERTS 3) Pier/Abutment cap (Bed block) Depth: For Spans less than 3.00m, Camber is provided in Bed block as shown in the drawing For Spans 3.00m and above 300 mm uniform thick is used. 4) Wearing coat Thickness : 75 mm (0.750m) in case of CC Wearing Course. 56 mm (0.056m) in case Bituminous Wearing Course. 5 H Value : Obtain the Height of Road Top from the LOWEST BED LEVEL from the site, say it is " h ". H = h - (Deck Slab Depth D1 or D + Wearing Coat Thickness) + 0.80 m. H values is fixed to nearest higher value of 1.0. 1.50,2.0,2.50,3.0, 3.50 or 4.00m 6 STRUCTURAL DETAILS OF SLAB CULVERTS : From the Span Length and H-value, all other Structural vales can be obtained from the TABLE. Detailed Drawings may be referred for Deck slabs Steel Details during Execution

CULVET DESIGN

VV Narayana

GENERAL ARRANGEMENT DRAWING

H>2.0 WEARING COAT

OVERALL SPAN

ROAD TOP DECK SLAB APPROACH SLAB

APPROACH SLAB BED BLOCK CLEAR PAN

WHEEP HOLES Ground Level

h

H

0.8m

Ground Level

LOWEST BED LEVEL

FOUNDATION

LEVELLING OURSE

B4

CULVERT

ELEVATION

B4

VV Narayana

H>2.0

ABUTMENT AND RETURN WALL SECTIONS

0.5

0.5/0.3

H

b3

LOWEST BED LEVEL

GROUND LEVEL

b2

0.3

b2

0.40

b3 b1 0.40 0.2 0.2

B1

0.80

0.80

b4

0.40

1.20

b4 0.2 0.2

+ WEARING COAT

H+ SLAB THICKNESS

ALL MEASUREMENTS ARE IN METERS

0.3

0.5

b1 0.40

B1 0.2

0.4

0.2

0.40

0.20 0.40 0.20

B2 SECTION OF ABUTMENT

B2 RETURN WALL SECTION

VVN

CULVERT

VV Narayana

GENERAL ARRANGEMENT DRAWING

H>2.0 WEARING COAT

OVERALL SPAN

ROAD TOP DECK SLAB APPROACH SLAB

APPROACH SLAB BED BLOCK CLEAR PAN

WHEEP HOLES Ground Level

h

H

0.8m

Ground Level

LOWEST BED LEVEL

FOUNDATION

LEVELLING OURSE

B4

ELEVATION

B4

12.0

PLAN 3.5

CULVERT

VV Narayana

GENERAL ARRANGEMENT DRAWING

(H