Tenders Are Invited For Repair Of Lysimeter Station In Colbitz: General Planning Services

Repair Of Lysimeter Station In Colbitz: General Planning Services. At The Beginning Of The 1960S, In Connection With The Construction Of The Colbitz Ii Waterworks, A Weighable Lysimeter Station Was Planned And Built On The Current Site Of The Infiltration Plant In The Colbitz-Letzlinger Heide. This Has Been In Operation Since October 1968 And Is Managed By The State Office For Flood Protection And Water Management Saxony-Anhalt (Lhw). It Includes 12 Weighable Soil Monoliths, Each With A Surface Area Of ​​1 M² And A Usable Depth Of 2 M, Which Are Planted With Heather-Typical Vegetation. Two Lysimeter Vessels Each Stand On A Total Of 6 Switching Weight Scales. The Facility Also Has Several Precipitation Collectors, A Bulk Collector For Recording Atmospheric Deposition And A Weather Station With Various Meteorological Sensors. The System Collects Basic Data For Water Balance And Substance Input Considerations Of Open Heathland And Makes Them Available For Scientific Evaluation. Since The Mid-1990S, The Previously Purely Manual Data Collection Has Been Supplemented Step By Step As A Forward Value Through Continuous Digital Recording And An Extension Regarding The Collection Of Meteorological Data. Due To The Almost Uninterrupted Monitoring Since The Facilitys Existence, A Scientifically Very Valuable Data Pool Has Been Created, Which Will Continue To Exist And Be Expanded. After More Than 40 Years Of Operation, Minor Concrete Spalling Occurred On The Structure, Which Was Treated Accordingly. In Recent Years, There Has Been Increasing Damage To The Concrete Body. In Addition To The Spalling, Which Was Increasing In Terms Of Area, Cracks Also Appeared In The Supports And Beams Right Down To The Steel Reinforcement. In Order To Clarify The Causes Of The Damage To The Structure And As A Basis For Developing Renovation Options, A Structural Analysis Was Commissioned In 2015, Including The Necessary Chemical, Mechanical, Static And Other Test And Laboratory Tests. As A Result, The Building Fabric Was To Be Evaluated. Here It Had To Be Determined That Due To The Constructive Unity Of The Beams And The Ceiling Of The Building, A Separate Demolition Of The Beams And New Construction Is Not Feasible And A Renovation As A More Cost-Effective Variant Is Not Feasible. Safety Measures Were Carried Out On The Structure At Short Notice To Ensure That The System Could Continue To Be Operated Without Risk. As Part Of A Feasibility Study From 2021, The Possibilities For A Partial Or Complete New Construction Of The Lysimeter System Were Examined And Variants For Its Implementation Were Developed. Furthermore, The Expediency Of Continued Operation Was Examined. The Feasibility Study Serves As The Basis For A Fundamental Decision About The Future Of The Lysimeter System. The Following 5 Project Variants Were Developed As Part Of The Study: Variant 1: 0 Variant (No Measures) Variant 2: Refurbishment Of Existing Building Shell And Technical Systems Variant 3: Replacement New Building With Old Test Arrangement Variant 4: Replacement Building With A New Test Arrangement Variant 5: Dismantling Without Replacement Construction For The Two Variants Of The New Replacement Building, A Further Comparison Of The Variants Was Then Carried Out With Regard To The Construction As A Reinforced Concrete Basement Or Pehd Container System. Taking Into Account The Expected Cost Framework Of The Preferred Variants And The Scientific Value Of The Series Of Measurements, The Trend Towards Their Continuation And The New Construction Of The System Is Clearly Recognizable And Justifiable. The Preferred Variant Is Variant 4: New Replacement Building With A New Test Arrangement In Pehd Container Construction. The New And Old System Should Initially Be Operated In Parallel For 4 Years In Order To Compare The Measured Values ​​Recorded. The Old System Will Then Be Dismantled. It Is The Dismantling Of The Lysimeter System And The Replacement New Building In Compliance With The Above To Plan Goals.