Water and Sewer Mains

The use of Urecon shallow buried pre-insulated pipe can result in a substantial reduction of excavation costs and may permit earlier project completion. U.I.P.® pre-insulated pipe can be installed in the active frost zone (with low wattage electric tracing if necessary) and resist freezing. The use of Urecon pre-insulated pipe has permitted hundreds of northern communities to obtain year round piped potable water, resulting inmajor social and health benefits. Savings are greatest when rock is encountered as it is far less expensive to pre-insulate and shallow bury water and sewer pipes than to blast and deep bury in rocky conditions.

In sandy or poor soil conditions, experience has shown that a considerable width to depth ratio is often required for excavation to permit conventional burial of pipelines below the frost zone. A Urecon pre-insulated pipe system, shallow buried (with low wattage electric tracing if necessary) could result in the excavation of one tenth the earth volume otherwise required. Substantial cost savings are thus realized and the danger to workers in deep trench conditions is avoided.

Bad Soil

A 3 m (9.8 ft) deep trench in type 4 soil, requires an excavated width at grade of 18 m (59 ft) to provide worker safety.

A 1 to 3 wall slope is required when excavating in type 4 soil conditions. Type 4 soil is defined as: soil that can be excavated with no difficulty using a hydraulic backhoe. The material will flow very easily and must be supported and contained to be excavated to any significant depth.

With its high moisture content, type 4 soil is very sensitive to vibration and other disturbances which cause the material to flow. Typical type 4 material includes muskeg or other organic deposits with high moisture content, quicksand, silty clays with high moisture content, and leta clays. Leta clays are very sensitive to disturbance of any kind. (Source: “Trenching Safety”, Construction Safety Association of Ontario).

Live Loads

Note: Urecon's standard jacket is suitable for H-20 highway loading at 600 mm (24 in) bury. Live H-20 load transferred to the insulation at 600 mm (24 in) depth of bury is 38 kPa (5.51 lbs/in2). Our system is rated 414 kPa (60 lbs/in2).

Live Loads on Buried Pre-Insulated Pipe

HEIGHT
OF COVER
LIVE LOAD TRANSFERRED TO PRE-INSULATED PIPE
Highway H201 Railway E802 Airport3
mm ft kPa lbs/in² kPa lbs/in² kPa lbs/in²
300 1 86,19 12.50 - - - -
600 2 38,34 5.56 181,96 26.39 90,60 13.14
900 3 28,75 4.17 162,79 23.61 84,67 12.28
1200 4 19,17 2.78 126,87 18.40 77,71 11.27
1500 5 12,00 1.74 114,94 16.67 69,57 10.09
1800 6 9,58 1.39 107,77 15.63 60,61 8.79
2100 7 8,41 1.22 83,77 12.15 54,13 7.85
2400 8 4,76 0.69 76,60 11.11 47,78 6.93
3000 10 - - 52,68 7.64 42,80 6.09
3600 12 - - 38,34 5.56 32,82 4.76
  1. Simulates 20 ton traffic and impact.
  2. Simulates 119,000 Kg/m (80,000 lb/ft) railway load and impact.
  3. Simulates 81,650 Kg (180,000 lb) gear assembly, 660 mm (26 in) spacing between tires and 1,676 mm (66 in) center to center spacing between fore and aft tires, under a rigid pavement 300 mm (12 in) thick plus impact.
  4. Source: IPEX Inc.

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