Objectif The aim of the project is to extend in a reliable manner the technique of controlled pressure grouting to the improvement of pile capacities of offshore structures and to develop new pressure grouting technologies in order to decrease the installation cost of offshore and possibly subsea structures.So far grouting techniques used in the offshore industry are very conservative and have not evolved in decades. New innovative technologies will lead to lower installation costs and improved performances of the pile foundation.It is difficult to present any brief, comprehensive conclusion to the study by reason of the diversity of approaches and work undertaken.It will be recalled that the study was to focus on the issue of pile grouting, in a two-pronged approach :1. theoretical analysis combined with triaxial testing and a computer program on claquage in ground subjected to grout pressure ,2. development, ie, design, construction and testing, of appropriate pilegrouting technologies.Both these approaches cover a vast area, one because of the ambitious programme covering the subject of widespread specialist controversy for many decades, and the other because of the multiplicity of the potential subjects of study.The claquage tests and its computer modelling have been brought to an advanced stage of development (although they cannot claim to be completed because of the complexities involved), and have yielded valuable information on the conditions to be observed for proper grouting.Many technological developments and improvements have been generated, by means of :1. an exhaustive laboratory study on grout mix design, followed by validation tests,2. research into chck valves and packers, which are the basis for selective grouting,3. modifications to grout mixing and pumping plant for precise and accurate proportioning on a floating platform,4. grouting parameter monitoring and recording,5. modifications to these techniques to suit (a) deep boreholes and (b) driven pile grouting.The analysis of the state of the art of pressure grouting and of potential problems existing in the offshore piling industry led to the selection of pressure grouting techniques which are developed under 3 aspects :- theoretical analysis of pressure grouting- detailed study of grouts for offshore applications- development of new technologiesThe theoretical research is related to the phenomenon of soil "cracking" and is divided in three stages :- the first stage is dedicated to a naturalistic description of the involved mechanisms.- the second stage consist of using an elasto-plastic consolidation finite element computer program to study the "cracking" phenomenon.- in the third stage "cracking" laboratory tests are to be performed on small scale models and interpreted with the help of numerical computations in order to produce a mathematical model of the "cracking" phenomenon.The detailed study of grouts for offshore applications consists of :- checking the suitability ofgrout used onshore for offshore application- developing new grouts for specific offshore applicationThis part of the project is mostly experimental and it involves intensive laboratory treating to determine all the grout properties which are essential for offshore use.The development of new technologies involves :- reviewing all the components of existing pressure grouting systems (i. e. pressure grouting units, non return valves, packers, grouting lines. . . ) and adapting them to offshore use. This phase consists in designing, building and testing components. - defining and testing inventive and low cost pressure grouting techniques and technologies to solve specific offshore piling problems. Programme(s) ENG-HYDROCARB 1C - Programme (EEC) of Community projects in the hydrocarbons sector, 1973-1985 Thème(s) 1.10 - ENVIRONMENTAL INFLUENCE Appel à propositions Data not available Régime de financement DEM - Demonstration contracts Coordinateur BELGIAN OFFSHORE SERVICES NV Contribution de l’UE Aucune donnée Adresse SCHERMERSTRAAT 46 2000 Antwerpen Belgique Voir sur la carte Coût total Aucune donnée
