Forums Posts

by smclanders@goldcoast.qld.gov.au Joined 25-05-2022 11:03 AM Posts 1

I have a project which we are designing and installing a DN450 SDR11 PE trunk watermain and have been told not to use inline thrust blocks on the PE (with PE Flex Restraints) pipe but rather install a section of DICL (with puddle flange) pipe at these locations. The in-line thrust blocks are required at SVs and at the end of the PE pieline where it connects to another pipe material - as per the Code requirements. The reason we have been told not install these onto the PE pipe is due to another Water Authority having previous issues where the PE ultimately breaks at the point where the PE and the concrete meet on the outside of the block - this apparently is even when a material is used between the pipe and the concrete surfaces. I was just wondering if others have also found this issue, and whether people beleive changing to the DICL section is a better design? TIA

by Shoalhaven City Council Joined 01-01-0001 12:00 AM Posts 24

SMClander, SW has used PE for most of our trunk main and some retic main replacements of the last 15 or so years. We typically use DICL thrust restraints due to the problem you have explain however some earlier projects were constructed with thrusting on bends ect and we havent experienced any issues. We also utilise PE thrust restraints in the later projects and havent seen any failures to date. If you are concerned the DICL thrust restraint is a proven solution but I havent found any issues with PE options to date. Matt Kidd Shoalhaven Water