Begrensning av skader som følge av grunnarbeider

BegrensSkade aims to develop new construction methods and improve cooperation between stakeholders, in order to minimize damage that may be caused by geotechnical and foundation work within construction projects. The project has a broad spectrum of involvement within the Norwegian construction industry, with 23 partners representing clients, contractors, consultants and insurers, as well as research institutes and universities. The background for the project is extensive industry experience of projects where geotechnical and foundation works have caused unexpected damage to nearby buildings and structures. Damage is especially common after the installation of drilled piles and anchors, as well as other foundation works. There is a clear and significant potential for improvement in the industry from the development of new and improved methods, which can eliminate or minimize ground deformations during construction projects. Such improvements can lead to direct cost savings due to reduced damage, operations that are more efficient, fewer delays and avoidance of disputes. The project has collected data and observations from a large number of key construction projects in order to map causes of damage. The analyses show that drilling for anchors and piles for geotechnical and foundation works significantly increases the risk of excessive settlements. In addition, the data show that drainage to deep excavations, causing pore pressure reductions in the soils, is not adequately assessed and accounted for. The project has focused on providing guidelines and recommendations on how to reduce the risk of excessive settlements by choosing alternative construction methods, planning and executing mitigating measures and using improved drilling methods and procedures. BegrensSkade has focused on studying the potential negative effects caused by drilling; the erosion of soil particles and the disturbance of clay, in addition to drainage and pore pressure reduction. Analyses of data have been undertaken for a full-scale field test and several on-going construction projects. The results show that the specific drill method and procedure are essential for the deformations. BegrensSkade has summarized recommendations on methods and procedures to reduce the risk of excessive settlements. In addition it is recommended that automatic logging of data should be required in projects where drilling is undertaken. It is also necessary to introduce certification requirements for drill rig operators within the industry. Thorough planning and focus on risk assessment are key factors for obtaining successful construction projects. In spite of this, systematic risk analyses are generally not carried out in projects that include geotechnical and foundation works. Evaluations of the effects on the surrounding areas required for tunneling projects should also be mandatory for temporary works such as deep excavations. BegrensSkade has developed a tool for risk assessment and management, which can be used in all project phases; planning, design and building, to reduce the risk for damage. The project has also included an assessment of the communication and cooperation, by interviewing the stakeholders in several completed construction projects. The conclusions from the study were that the most important factor for the success of a project, is that all stakeholders have a reasonable contract, which builds trust and simplifies cooperation. In addition, it is important that all stakeholders have the right qualifications and get involved in the communication. As a result of the BegrensSkade project, the Norwegian Geotechnical Association (NGF) has taken the initiative to develop and release a new Guideline for deep excavations (Byggegropsveilederen), which will contain results and recommendations from BegrensSkade. The guideline will act as a reference document which will be used as a standard by the clients, consultants and contactors within the industry.

Prosjektet har som mål å utvikle nye utførelsesmetoder og forbedre samhandlingsprosesser for å begrense skader som følge av grunnarbeider. Det oppstår for mange uønskede skader i dag, f.eks. ved utførelse av stagboring og setting av stålkjernepeler. Det l igger betydelige besparelser i å utvikle nye metoder og prosedyrer for å begrense skader innenfor bygg, anlegg og eiendomsbransjen. Prosjektet ser på hele kjeden av årsaker og forbedringsmuligheter, og består av å (1) samle inn data og erfaringer fra utf ørte prosjekter og kartlegge årsaker til skader, (2) utvikle nye metoder og tiltak som begrenser skader, (3) utvikle verktøy for fare-, sårbarhets- og risikovurdering knyttet til valg av optimal løsning, og (4) forbedre samhandling i bygg- og anleggsprose ssen med både nye kommunikasjons- og formidlingsmåter og nye prosesser for dialog og tillitsbygging. For å utvikle de nye metodene, veiledningene og samhandlingsmetoder, er det oppnådd en bred tilslutning fra den norske BAE-bransjen. Prosjektet arbeider m ed å: . etablere årsaker til skader som følge av grunnarbeider eller grunnforhold; . utvikle nye metoder og tiltak for å begrense skader; . utarbeide prosedyrer for setting av stag, stålkjernepeler og borede stålrørspeler; . dokumentere at de nye metode r reduserer skader uten negative effekter; . utvikle risikobasert(e) metode(r) og utarbeide veiledning; . utvikle nye kommunikasjons-/formidlingsmåter i bransjen; . lage veiledere for utførelse i praksis. Partnerne vil kunne ta i bruk de nye metoder så f ort de er utviklet og dokumentert, og dermed oppnå innsparinger allerede fra høsten 2013. Dette i form av færre skader, raskere gjennomføring, færre forsinkelser og færre tvistsaker. Når de nye metoder for utførelse, ny risikovurdering og beslutningstakin g i byggeprosjekter og styrkede samhandlingsprosesser settes i samspill i 2015, vil de nye veiledere for prosjektering og utførelse, opplæringsplan og forhåpentligvis et nytt forum i hele bransjen realiseres.