Essex Groundworks Supplies Ltd

-	Caisson Units
-	Box Culverts

Concrete Drainage - Caisson Units

Caisson Units (Milshaft)
Design Chemical Class DC-4 Resistance

Reinforced manhole units suitable for sinking by the caisson method manufactured to BS EN 1917 & BS 5911- 3 and carry the BS Kitemark where Appropriate.

Components (DN2400 - DN4000)

A nominal 1.9m base shaft ring comprised of a concrete cutting shoe providing a 12mm overbreak and a standard 0.5m deep shaft unit.
Chamber sections in 0.5m and 1.0m depths
Jointing plates
Butyl resin joint sealant
Lifting brackets
Landing slab 1.0m deep shaft ring
Landing slab in two halves
Landing slab support angle cleats
Cover slab

The DN4000 caisson units are manufactured in two halves and have a separate steel cutting shoe comprising of components 2 to 9 inclusive as above.

Caisson Units
	Weight of Base Unit & Cutting Shoe (kg)	Wall Thickness (mm)	Chamber Wt/m Depth (kg)
2400	2400	130	2560
2700	3040	140	3060
3000	3800	160	3810
4000	-	200	3220 per half ring

Landing Slabs
	Access Size (mm)	Thickness (mm)	Approx Wt (kg)
2700	900	150	2100
3000	900	150	2600
4000	900	165	2680 per half slab
Full or half landing slabs are available.

Cover Slabs
	Access Size (mm)	Wt (kg)
2400	*675 x 675	2228
2700	*675 x 675	3068
3000	*675 x 675	4242
4000	900 x 600	9900
*These sizes are to provide a 600 x 600 or 645 x 645 manhole top access when used in combination with up to three adjusting units to the require size access and depth of make up. Other sizes are available to order.