|
|
|
|
|
|
|
|
|
Products > Box Culvert
|
|
| |
PDF Brochure | OKA PRECAST RC BOX CULVERT
_________________________________________________ OKA provides an extensive range of precast reinforced concrete box culverts from nominal width of 300mm to 3660mm, which are further categorized in accordance to the width of culverts as follow: 1. Standard Size Box Culvert (width from 300mm to 1800mm) 2. Supersize Box Culvert (width from 2135mm to 3660mm) OKA box culverts are available with and without dry weather flow (DWF) channels. All box culverts are manufactured under controlled factory environment with stringent ISO 9001:2008 quality management system.
|
| DESIGN CRITERIA |  | | ➢ | Structure design of OKA box culvets are in accordance to:- BS 5400 : Part 4 : 1990
- BD 31/01 - The design of buried concrete box and portal frame structures
- MS 1293 : Part 1 : 1992
| | | ➢ | OKA box culverts are designed to withstand a standard 2m (max.) of superimposed backfill depth and 45 units of HB vehicle live load. | | | ➢ | OKA Standard size box culverts also complied to 112.5 kN proof load applied over an area of 320mm x 320mm at any position on the culvert's lid. |  | | | ➢ | Minimum backfill depth of 600mm over OKA box culverts are recommended to avoid undesirable direct impact load. | | | ➢ | Hydrostatic pressure is relieved by provision of weephole placed along the centerline of the invert wall. | | | ➢ | Please kindly refer to our marketing personnel for assistance if special design are required for other loading conditions to suit your project requirements. |  | | MATERIAL SPECIFICATION | | | | ➢ | Concrete characteristic strength at 28 days:
Grade 30 to Grade 40 | | | ➢ | Nominal cover for OKA Standard Size and Supersize Box Culverts are 25mm and 30mm respectively. | | | ➢ | Bulk density of backfill soil to be 19 kN/m3 | | | ➢ | Coefficient of earth pressure at rest = 0.5 | | | ➢ | Backfill material adjacent to invert wall should be granular type of soil. Backfilling sequence of even layer at alternate approach side of box culvert must be observed. |
| HANDLING, STACKING, LAYING & JOINTING | | • | Handling: | A spreader beam is recommended to be used with steel pins and lifting cables to avoid cracking at junction of side wall and base slab. | | • | Stacking: | Box culverts' invert and lid are to be stacked on level and stable ground or timber bearer to avoid cracking due to undesired localized load. | | • | Laying: | Box culverts are to be laid on layered of well compacted granular materials, a surface blinding of the fine materials will assist leveling. RC capping slab shall be provided if piling is required.
| | • | Jointing: | OKA box culverts are supplied in butt joint. Gaps between box culverts are normally filled up with cement-sand mortar.
|
OKA STANDARD SIZE BOX CULVERT
______________________________________________________ |  | 
|
OKA SUPER SIZE BOX CULVERT
_______________________________________________ |  | 
|
 |
Notes:
OKA box culverts with opening at Lid or Invert can be manufactured upon request.
Box culverts with others specified strength and dimensions can also be manufactured upon request. (Non standard products).
| March, 2020
|
Download PDF Brochure Go to Top
|
|
|
|
|
| |
|
|
|
|
|
|
