Geological and geotechnical information

There is an important difference in geological and geotechnical required data for the analysis of a borrow area compared to the data required for the analysis of a reclamation area. 

Tests done in the borrow area are mainly aimed at determining the quality, quantity and dredgeability of the soil. The soil properties (e.g. grading) might change during dredging and therefore not all tests are useful or at least need to be treated with care (e.g. Particle size distribution tests). 

Test done in the reclamation area are mainly aimed at estimating settlements caused by the placement of the reclamation fill and at checking the stability, bearing capacity and liquefaction resistance of the reclamation area and its edges (revetments, retaining walls, bunds etc.). 

In the sections 3.4.2.1 and 3.4.2.2, the geotechnical data requirements for borrow areas and reclamation areas are treated separately. 

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Each of these soil categories requires its own approach. A first guideline when evaluating the required geological and geotechnical information for a dredge area can be found in Table 3.1. 

Geological and geotechnical information of the subsoil in the reclamation area... 

Site characterization is the initial phase of the site specific ground response analysis involves acquiring, processing and interpretation of quaUtative and quantitative information of the site such as geological, geotechnical, seismic and seismotectonic details to evaluate the hazard based on level of site response. The scope of site characterization varies from simple to complex depending upon several major factors including... 

The traditional geotechnical survey is characterized by discrete information. It means that old survey methods cannot provide comprehensive data on the geological structure, substance composition and properties of the whole pipeline route. This principle is not observed in all the three main gas pipeline cases. The technical documentation of the Baku-Tbilisi-Ceyhan pipeline, the South-Caucasus Pipeline system, and particularly of the North-South Caucasus Gas Pipeline does not include longitudinal geotechnical profiles of the route and the pipeline corridor in the geotechnical maps. Trial pits and boreholes that are arranged approximately 1,5-... 

Thematic geological maps tailored for engineering purposes with pertinent information on lithological properties are essential. These geotechnical features that should be displayed are, for instance, general foundation suitability of dilferent terrain for preliminary assessment on suitability for foundation work and relative compressibUity/settlement of different terrain. 

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