Methods In Engineering Geology Research Articles

Engineering Geological and Hydrotechnical Conditions of Primorsko Fishing Port, SE Bulgaria

The present study is related to the preparation of a project for the construction of a fishing port for small vessels in the area between the mouth of the Dyavolska River and Cape Kyupria (SE Bulgaria) with the aim of protecting the water area from dangerous wave loads, geological and meteorological impacts and creating conditions for safe docking, service and accommodation of the fishing vessels. The geological structure, geomorphology and physical-geological phenomena in the water area of Primorsko Fishing Port in the southern part of Cape Kyupria have been clarified. An engineering-geological project was prepared, the physico-mechanical indicators of the construction soils and the geotechnical characteristics of the ground base were determined. A complex package of scientific and engineering-geological methods was applied during the implementation of the project. Based on the obtained scientific and applied results, recommendations were made to the Municipality of Primorsko in connection with the construction of the port. The foundation conditions of the designed wharf with a walled pier are favorable for the construction of the wharf with gravity hydrotechnical facilities.

Stages and staging of the study of the seabed for earthmoving systems

The development and development of minerals and building materials in water areas, the laying of underwater communications, planning and dredging underwater are preceded by detailed surveys of soil massifs. They establish the lithology and genesis of deposits, bottom surface bathymetry, physicomechanical, acoustic and other properties of underwater soils. These studies are mainly subordinated to the tasks of geology. At the same time, for the development of the deep-water part of the World Ocean, it is planned to use soil development and transport equipment. The kinematic parameters of the equipment used for engineering and geological research do not correspond to the kinematics of existing or planned underwater systems. Despite some progress in the development of engineering-geological methods for studying the ocean, there are currently no reliable data on the mechanical properties of bottom sediments in natural occurrence. Practically the only way to identify the strength properties of deep-water soils is the sampling method (tubes, grabs, dredges). Soil characteristics are determined from samples brought to the surface in a shore or ship laboratory.
 One of the specific features of the tests being carried out is the consideration of hydrostatic pressure, the effect of which on three-phase soils is especially large. Therefore, it should be expected that the measurement errors of the characteristics of bottom sediments in atmospheric conditions due to the violation of their structural relationships during ascent from great depths can differ by an order of magnitude or more from the true values ​​of the parameters of the soil environment. Thus, in order to determine the operating conditions and set external loads on underwater digging machines, it is necessary to measure the strength, deformation and other characteristics of bottom soils in natural conditions under hydrostatic pressure. This paper considers the methods and technical means used for deep-sea exploration of the seabed. Particular attention is paid to engineering-geological methods, which make it possible at the stage of detailed exploration to obtain not only predictive estimates of the mineral resources of the World Ocean but also to determine the physical and mechanical properties of bottom sediments, on which deep-sea digging machines will have to work.

Design with Geo-Hazards: An Integrated Approach from Engineering Geological Methods

An engineering geological approach to analysed geo-hazards affecting engineering and planning design decisions is presented. The methodological procedures include hazard identification, hazard assessment, site vulnerability, economic cost, environmental impact, risk assessment, social acceptability, decision analysis and engineering design criteria. The practical application of the Engineering Geological Methodology (EGM) is shown in several case studies: dam safety problems due to slope instability and induced seismicity during reservoir filling; seismic hazard assessment in regions with insufficient seismic data and tectonic information; and large scale geo-hazards due to giant landslides and related tsunamis. The EGM approach can provide fundamental criteria for engineering decisions and territorial planning. Social acceptability should be included in the decision analysis being evaluated according with the hazard level of the geological process and the corresponding risk of the affected elements. Examples of geo-hazards and their social acceptability are presented.

Special purpose engineering geological methods for mapping and interpretation of rock mechanical phenomena : Brauer, V; Pahl, A Proc 6th International Congress International Association of Engineering Geology, Amsterdam, 6–10 August 1990V1, P567–574. Publ Rotterdam: A A Balkema, 1990

Special purpose engineering geological methods for mapping and interpretation of rock mechanical phenomena : Brauer, V; Pahl, A Proc 6th International Congress International Association of Engineering Geology, Amsterdam, 6–10 August 1990V1, P567–574. Publ Rotterdam: A A Balkema, 1990

Engineering geological methods applied in mountain road survey - an example from Baitadi-Darchula road project (Nepal)

Engineering geological studies were carried out for the Baitadi -Darchula Road in prefeasibility, feasibility, and detailed design stages. Methodology, application, and results from each stage are presented together with the geology and geomorphology of the region.

Main activities of engineering geologists in the field of radioactive waste disposal

The paper describes the work of engineering geologists during the planning and construction of underground repositories for radioactive wastes. Various engineering geological methods for the description of rock structure, for the measurement of thermo-mechanical parameters and for the quantitative demonstration of structural stability are discussed in detail. For a waste disposal mine, the load bearing capacity of the rock, the protective properties of the surrounding rock formations and the geological stability of the area are important factors in a safety analysis of which geotechnical stability analysis is a critical part. Such an analysis comprises an engineering-geological study of the site, laboratory and in situ experiments, model calculations, long term monitoring, and special geological and geochemical investigations. Some general criteria to apply in performing a geotechnical stability analysis have been developed on the b of theoretical consideration and practical experience. They have been used in preliminary repository design calculations for the Gorleben site and for proving the safety of the Konrad site, FRG. Some results of these calculations are given. According to the multi barrier principle, the geological setting must be able to contribute significantly to the waste isolation over long periods. The assessment of the integrity of the geological barrier can only be performed by making calculations with validated geomechanical models. Natural barriers (consisting of the soil or rock formations surrounding the waste) should ensure that the inflow of water capable of leaching and/or the outflow of contaminated water from the final repository into the biosphere either is fundamentally impossible or at least can be kept within acceptable limits as a result of the natural geohydraulic conditions Therefore, the determination of water conductivity and water permeability along discontinuities is necessary in order to evaluate the barrier efficiency of crystalline host rock. Various engineering geological data are required for the siting, for the design and construction, and for the safety analysis of a repository. These data can only be attained by the execution of a comprehensive site specific geomechanical exploration and investigation program. Recommendations for such a program are given.

Accumulation of heavy minerals in landslides in the Burgas area of the Black Sea coast

The combination of mineralogic and engineering-geological methods in the investigation of littoral landsliding in the Burgas region of Bulgarian Black Sea enabled us to specify the conditions of accumulation of some important heavy minerals. Numerous regularities are observed in the formation of the deposits in the shore profiles within the beach nip and in shallow waters. This mainly concerns the accelerated separation of the heavy minerals in relation to the evolution of the coastline and the dynamics of the landslides in the part of the slope above sea level. The most perfect separation of the magnetic fraction is observed along the Sarafovo coast. Here, the nip is the typical border line of differentiation of heavy minerals. In the coastal landslide area near Ravda, where a high rate of movement of sliding masses has been observed during the last several years, the sum of the heavy components in the sediments of the nip area was 5.6% in 1975, increasing to 10% in 1980. For the Sarafovo shore the sum is higher, 21.07% in 1975 and 96.6% in 1980. The landsliding shores of the Burgas area of the Bulgarian Black Sea coast are interesting models of natural separators of heavy minerals.