The term "Geotechnical Processes" (or Geotechnical engineering) has its origin in the English speaking economy. Geotechnical processes include planning, exploration, specialized heavy construction methods, equipment and machines, construction and maintenance of geotechnical buidings. Geotechnical test of the preconditions for its use is what all is about.
processes are an interface between Specialized heavy construction, disposal site construction, rehabilitation of abandoned industrial sites and water handling, especially for acid mine water. The combination of loose and solid rock as building ground and building material and the
Because of our experience of both, as costumer and as enterprise, we do know the problems in the planning and construction stages. Therefore we do have a good basis to construct geotechnical buildings which are optimized in function, life time, investment costs and running costs.
One has to keep in mind, that products of geotechnical processes are determined by the given building ground. That means that an insufficient description or exploration of the building ground leads to a product which probably does not fulfil the required properties. The same is true if the method is not proberbly used, equipment are not properly used or unsuited materials are used. Therefore quality assurance (for instance in gravel stone columns) and perpetuation of evidence (for instance in filling and closure of openings in old mining), are also components of geotechnical processes. Therefore it is absolutely necessary to determine all properties (parameters of condition) of the building ground in the exploration stage as precise as possible. Furthermore all parameters of conditions have to be given to all involved partners completely. But, most of the exploration of the building ground is done at pointwise or linewise exploration of condition (for instance exploration by drilling, sampling, ram-sounding, pressure sounding). Most of these methods are indirect methods. The examples show, that soil mechanical properties are not determined directly but by help of calibrations, conclusions from field tests and comparisons with other results. One example is the indirect determination of the compactness and/or the void ratio from cone pressure, skin friction and pore water pressure profiles of a cone penetration test (CPT): With the assign of core drillings to soil profiles and the summary in a geotechnical report results are available for the planning and geotechnical engineer as well as the company. The is solid base for the following geotechnical process.
Beside others , the following standards define necessary exploration methods and the number of necessary tests:
- DIN 4020 - Geotechnical tests for construction works,
- DIN 4021 - Exploration with trenches and drill-holes as well as sampling,
- DIN 4094 - Exploration with sounding measures etc.
Another important problem arises with the construction of spacious geotechnical buildings, especially works in rehabilitation of former mining sites. The measures for the creation of the soil mechanical and/or hydro-mechanical stability of extensive areas under mining law which have been carried out in the process of rehabilitation of abandoned brown coal mining sites in East Germany have been accompanied by a lot of measurements and in situ tests. The result from measurements or tests at pointwise or linewise have to be summarized. The conclusions have to be made for the rehabilitation areas (building ground). Statistics and probability theory are used to get representative, significant results. But especially during the rehabilitation of abandoned open cast mining sites it has to be kept in mind that the building ground is inhomogeneous and anisotropic. Anomalies in the building ground are always possible. Such anomalies can be detected with geophysical tests like geo-electric and geo-seismic. Detected anomalies can be tested in detail. The result from field tests can improve the statistics from other areas. But are geophysical methods also suitable for the calibration of non-soil-mechanical field tests? Here is given a reference to .
For the disign planning and evaluation of geotechnical buildings (strain-, stress-, consolidation calculations, safety proofs etc.) are available the program systems and their modifications:
- FEEREPEGT (extended and modify) FEMDIS, 
- PLAXIS, Plaxis B.V., Delft, Niederlande
- FLAC, Intasca Consulting Group, Inc., Minneapolis, Minnesota, USA
- MATHCAD, Mathsofts Engineering and Consulting, Inc.
La Conchita, California, 1995; 350 m long, 120 m wide,
1.300.000 cbm volume;
Photo by R.L. Schuster, U.S. Geological Survey
Los Vaqueros Dam,California, USA,
place of large rocks (rip-rap) on the upstream-face
Left: CPT, cone pressure (pc) behaviour (line): pc as function of the depth and the time, pc=f(h,t), r=const.;
Right: CPT, cone pressure (pc) behaviour (field), pc as function of the location and the time; pc =f(h,r,t), h=const.