What’s in a Geotechnical Investigation
Establish the right basis and assess the data.
In most cases, a geotechnical investigation starts as a desk study, with an investigation of the history of the site, using geological, hydrogeological maps and historical evidence from the literature as well as geotechnical data from past studies, which have been carried out at the area of interest.
As soon as the most efficient way to obtain the geological and geotechnical information, which are necessary for the project, is specified, an on-site visit and recording of the geotechnical or geological information of the area is scheduled. Sampling bore holes, static or dynamic penetrometer tests, exploratory wells, geophysical tests; chemical analyses are carried out supplemented by any other method, which is required in each case, for the appropriate investigation of the project’s geotechnical conditions.
Depending on the requirements and the nature of the project, in situ tests are executed, or monitoring devices are installed for the recording of the behavior of the soil, the response of the manmade structures and the ground water table fluctuations with time.
During the execution of the sampling bore holes and pits, soil, rock and underground water samples are collected as well as any other specimen, which is considered necessary for the appropriate investigation of the geotechnical conditions of the project. Subsequently, a preliminary evaluation of the geotechnical conditions and the soil stratigraphy is carried out on the site. Additionally, the soil samples, as well as any other observation or information which may be useful for the best evaluation of the project are thoroughly recorded. Following this detailed recording of the onsite conditions, it is decided which laboratory tests will be further performed. The soil samples are wrapped and then transported to the laboratory in such a way so that their natural composition and structure are not disturbed. Based on the laboratory testing program, the samples are prepared and the necessary laboratory tests are executed, following the current National and European guidelines. Our company owns a certified (ΕΛΟΤ EN ISO 9001:2008) soil and rock mechanics, as well as concrete control laboratory.
Upon completion of the lab tests, the geotechnical investigation report is compiled, where all the data are analyzed and evaluated in detail, the required geotechnical calculations are performed and the necessary geotechnical evidence and construction guidelines for the completion of the project are outlined.
Depending on the project’s conditions and the client’s requests, a special foundation, retaining, underpinning and/or restoration study is also compiled, following the data and the geotechnical challenges of the project.