Tenders Are Invited For Canal Construction – Retentionsbodenfilteranlage

Canal Construction – Retentionsbodenfilteranlage. The New Retention Soil Filter (Rbf) To Be Built Has A Total Filter Area Of ​​Approx. 1,700 M2. With The Planned Impoundment Height Of 1.25 M, The Retention Volume Is Approximately 2,500 M3. To Achieve The Retention Volume, The Pool Must Be Constructed At A High Position. A Dam Must Be Built Along The Norfbach. The Dam Crest Was Set At 40.00 M Above Sea Level. It Is Then Around 0.30 To 0.50 M Above The Current Top Edge Of The Ground In The South Of The Pool Location And Around 1.70 M Above The Current Top Edge Of The Ground In The North Of The Pool Location. In The South Of The Pool Location, For Reasons Of Space, A Retaining Wall Made Of In-Situ Concrete Will Be Built Instead Of An Embankment Along The Entire Length Of The Pool. Due To Insufficiently Stable Subsoil Conditions In Parts Of The Foundation Base Of The Pool, The Soil Is Improved Using Mixed Binder Milled Into The Subsoil. The Entire Retention Floor Filter Is Sealed Against The Substrate With A Plastic Sealing Membrane (D = 2 Mm). The Plastic Sealing Membrane Is Chosen Because Of The High Demands On The Long-Term Durability Of The Seal And The Potential Dangers Of Rooting And Penetration By Animal Passages. The Sealing Membrane Is Pulled Up To At Least Above The Maximum Water Level In The Rbf And Secured Against Slipping In A Surrounding Trench. To Protect The Sealing Membrane, A Protective Fleece Is Laid On Both The Bottom And Top Sides. An Additional Geogrid Prevents The Topsoil Slopes From Slipping. In The Area Of ​​Buildings, The Sealing Membrane Is Attached To The Building Wall Using Clamping Rails. Where Pipes Penetrate The Sealing Membrane, They Are Made Of Pe-Hd So That A Wall Collar Can Be Welded All Around, To Which The Sealing Membrane Is Then Welded. Sand 0/2 With A Steep Grain Line And Limited Fine And Coarse Content Should Be Used As The Filter Substrate. In Addition, The Filter Sand Is Provided With A Carbonate Content Of > 20% In Accordance With The Retention Soil Filter Manual. If The Natural Carbonate Content Is Too Low, Carbonate Is Added. The Installed Filter Substrate Must Be Filter-Stable To The Drainage Body And Must Not Be Compacted During Installation. The Height Of The Filter Structure Is 0.75 M. A 5 Cm Thick Carbonate Cover Layer Is Arranged Above The Filter Structure. The Upper Edge Of The Filter Is At A Height Of 38.25 M Above Sea Level And Therefore About 1.0 M Below The Current Top Edge Of The Ground (38.50-39.50 M Above Sea Level) At The Location Of The Retention Soil Filter. The Filter Drain Structure Is Arranged At The End Of The Retention Soil Filter, From Where It Is Drained Into The Norfbach. From A Water Level Of 36.88 M Above Sea Level In The Norfbach (Corresponds Approximately To An Hq1), A Backflow Flap At The Outlet Of The Drain Channel Into The Norfbach Prevents A Backflow Into The Filter Drain Structure. At The Same Time, The Level Measurement Provided In The Norfbach Registers A Water Level