Engineering Geological Studies Research Articles

Rock Slope Stability Problems in Wadi Quaz-Dam Site No. 2, Jeddah-Saudi Arabia

The present investigation deals with the engineering geological studies of soil and rock masses in the Wadi Quaz area-Dam No. 2, East of Jeddah. Wadi Quaz area-Dam No. 2, East of Jeddah, Saudi Arabia often faces floods during rainy seasons, so it is so urgent to investigate the area before building any dam or preventing water from flow. Preventing water from flow will produce new dangerous factors such as uplift force which may cause the dam failure. To have a better understanding of the factors that may affect the slope stability, many rock slope locations are observed in detail to assess the effect of discontinuities formed in the rock masses. Fieldwork and Laboratory tests were carried out on soil and rocks. Soils included identification of soil type using unified soil classification system, permeability, water content and field density were done for soils. Rocks include identification of physical and mechanical properties such as: rock type, degree of weathering, rock strength, RQD, joint spacing measurements, and geometric properties (Dip, and Dip direction). Different methods were used to evaluate the potential failure in the studied area depending on rock mass rating and slope stability analysis. The well-known classification of rock masses titled Rock Mass Rating system [1] was used for categorizing the rock masses in the studied area besides slope mass rating [2] which would help to estimate the rock stability. The kinematical analysis was applied to investigate the potential failure mode which might occur in the dam abutments. This paper will provide the stability of dam abutments in both summer season and winter season besides general estimation of the seepage problems related to the soil and according to its permeability.

Інженерно-геологічна характеристика порід лесово-ґрунтової серії опорного розрізу Бояничі (Волинська височина)

Boyanychi key section is one of the most complete, most famous and best studied sections of periglacial loess-soil series of Volhyn-Podillia. An almost complete history of the formation of rocks for the last 600 000 years is represented here. There is total thickness of loess-soil series approximately is 25 meters in this section. This key section is stratotype of Sokal fossil soil. Pseudomorphs after the structures of cellular ice of Boyanychi palaeocryogenesis stage were allocated here for the first time for Volhyn-Podillia and individual significance of this stage was substantiated as one of the most ancient in the Pleistocene. Boyanychi key section was studied by the use of practically all methods which apply for the investigation of Pleistocene deposits (in particular, micromorphological, palaeocryogenic, palaeomagnetic, engineering-geological, palaeontological, methods of absolute dating of deposits etc.). Detailed description of the section and the results of engineering-geological studies of rocks of all selected loess and palaeosoil horizons were done. Individual properties of selected stratigraphic horizons and their dependence on the paleogeographic conditions of sedimentation were displayed. Key words: loesses, fossil soils, palaeogeographical conditions, palaeocryogenesis, engineeringgeological features, subsidence, Volhynian Upland.

Investigation of the geological and geotechnical characteristics of the Tanguyeh dam site in southeastern Iran

Tanguyeh dam, an embankment dam with a clay core, located in southeastern Iran, is the main hydraulic structure in Kerman Province. The study area, as one of the most active tectonic zones of Iran, is covered by coloured melange and pyroclastic rocks of different lithologies. In this study, we take into account the engineering geological properties of rock masses such as discontinuities, the degree of weathering, the hydraulic conductivity along the dam axis, and ancillary structures in order to determine likely problems and necessary precautions. The significance of this study lies in the complex geological conditions and existence of a heterogeneous rocky knob along the dam axis. For this purpose, field studies such as production of an engineering geological map, study of discontinuities, permeability tests of Lugeon and rock quality designations,and sampling of recovery cores for laboratory tests are implemented. Finally, the results of the field tests and engineering geological studies are investigated.

Improving female participation in professional engineering geology to bring new perspectives to ethics in the geosciences.

Many papers have been published related to the retention and advancement of women in sciences. Engineering geology is one of the professional areas where women have not yet broken the gender barrier. The research issues of this paper are focused on why female students “leak out” at the end of engineering geology studies, and what can be done to encourage them to complete their degrees with an engineering career in mind. The author has studied students’ preferences of the final year project required to complete their degree at the University of Salamanca (Salamanca, Spain). It has been found that most female students are choosing a more theoretical final project instead of a practical one relevant to professional employment, contrary to their male peers. Focus group meetings with the students showed that at the end of five years of engineering geology training, many female students, unsatisfied with the content of their courses, feel that their expectations had not been met. They often have preferences for traditional geology rather than applied branches of the subject. Also, they do not feel comfortable with future job prospects in the profession. From the findings of this research it is clear that tutoring and mentoring would be valuable from the beginning of studies to allow all students to become aware of the content and the potential outcomes of engineering geology studies. In the case of female students, it is particularly important for them to know from the very start that they are about to join what is still a man’s world but that they are capable of achieving just as much as men can in the profession. Most importantly, the involvement of more female engineers in professional engineering, including teaching duties, should serve as example and role models in students’ education and future careers.

Інженерно-геологічна характеристика порід лесово-ґрунтової серії опорного розрізу Коршів (Волинська височина)

Korshiv key section is one of the best studied and most complete sections of periglacial loess-soil series of Volhyn-Podillia. There is total thickness of loess-soil series approximately is 30 meters in this section. This key section is stratotype of Korshiv fossil soil complex and Lutsk fossil soil. Pseudomorphs after the structures of cellular ice of several stages of Middle Pleistocene palaeocryogenesis were allocated here for the first time for Volhyn-Podillia. Detailed description of the section and the results of engineering-geological studies of rocks of all selected loess and palaeosoil horizons were done. Individual properties of selected stratigraphic horizons and their dependence on the paleogeographic conditions of sedimentation were displayed. Key words: loesses, fossil soils, palaeogeographical conditions, engineering-geological features, subsidence, Volhynian Upland.

Engineering Geological Study of NWCT Tunnel in Iran with Emphasis on Squeezing Problems

This research is concerned with the assessment of squeezing potential along of North Water Convey Tunnel in Iran (NWCT) and its stability analysis has been carried out. In this study, the most suitable methods are utilized for the stability analysis and design of support of the tunnel. For the empirical investigation, the rock mass were classified based on RMR, RMi, GSI and Q systems. The geomechanical properties of the rock mass were determined from the laboratory and field investigations. The results obtained from the analysis show that the tunnel is highly unstable due to the presence of a fault and hence strong supports are need in these regions. Because of high overburden (up to 600 m) and the presence of faults and crushed zones, it was necessary to evaluate squeezing potential along the critical section of the tunnel (Lot2). Therefore, empirical and semi empirical approaches and a new method as critical strain have been used for evaluation of squeezing potential. Some experimental equations were used for estimation of critical strain and also Flac2D program has been used to calculate tunnel convergence. Consequently, squeezing index was estimated. This index is used for determination of squeezing degree. As a result, fair squeezing potential was found in crushed zones along the tunnel route.

Geotechnical Engineering Assessment of the Nargesi Damsite, Southwest Iran

This paper describes the results of the engineering geological investigations and geotechnical studies performed in the Nargesi dam site. The dam foundation located on the sedimentary rocks of Neogen period. To conduct this study, the steps including field and laboratory investigations, surface discontinuity surveying, drilled borehole data, and permeability were performed on dam foundation. Besides, the evaluation of the dam foundation was carried out by water pressure tests, which indicate the necessity of creating a grout curtain below the dam foundation. The permeability and groutability characteristics of the Nargesi dam foundation are significantly affected by geology of the site. The rock mass properties of the test section obtained from secondary permeability index (SPI) completed with the degree of jointing of the drill core acts as a useful reference for ground treatment design. Here, the performed laboratory tests were as: determination of density, moisture percent, porosity percent, water absorption, uniaxial compressive strength, Point-load strength index (Is50), p-wave velocity (Cp), s-wave velocity (Cs), deformability, and triaxial tests. The rock mass properties and classifications of the damsite is assessed using rock mass rating, the rock quality (Q), and the geological strength index classification systems. The strength and modulus elasticity of rock masses were determined through the equations proposed by different researchers. According to the findings of this work, except for some cases, there is a reasonable correlation between SPI and rock quality designation values. Based on these results, grout type and composition was suggested for the design of grout curtain.

Profiling of K0 lateral stress coefficient in soils using paired directional G0 ratios

Abstract Using a special database compiled from directional shear wave velocity measurements at 12 well-documented sites, the geostatic stress state and stress history are evaluated from shear stiffness ratios. At each site, a benchmark profile of lateral stress coefficient (K 0 ) was detailed using direct in-situ methods (i.e., self-boring pressuremeter, total stress cells, and/or hydraulic fracture), and/or laboratory methods (i.e., suction, consolidometer, and/or triaxial stress path testing). Also, the yield stress ratio (YSR), or more common parameter: overconsolidation ratio (OCR), was available either from series of consolidation tests on undisturbed samples procured from various depths and/or engineering geology studies, or both. Statistical expressions are derived to relate both K 0 and OCR in terms of the ratio G 0,HH /G 0,VH as well as other factors.

Udział Państwowe go Instytutu Geologicznego w rozwoju gospodarki narodowej

Wklad PIG w rozwoj gospodarki narodowej wyraza sie odkryciami kopalin uzytecznych, ktore są podstawą roznych galezi przemyslu, oraz wieloma osiągnieciami w zakresie badan hydrogeologicznych i geologiczno-inzynierskich. Do najwazniejszych osiągniec nalezą odkrycia unikatowych w skali światowej zloz: rud miedzi kolo Lubina, siarki rodzimej kolo Tarnobrzega, lubelskiego Zaglebia Weglowego, a takze wielu zloz: wegla brunatnego, soli kamiennej, polihalitow, cynku i olowiu, tytanomagnetytow z wanadem, kaolinu, barytu i duzej ilości zloz kopalin skalnych. Baza surowcowa Polski opiera sie na kopalinach uzytecznych umiejscowionych w ponad 4200 zlozach o lącznych zasobach powyzej 205 mld t. Na podstawie wartości wydobywanych surowcow mineralnych omowiono pozycje Polski wśrod krajow dysponujących wlasnymi surowcami mineralnymi. SHARE OF THE STATE GEOLOGICAL INSTITUTE IN DEVELOPMENT OF THE NATIONAL ECONOMICS During its 70 years of existence the State Geological institute has carried through the studies of a geological structure of the country to create the basis for exploration, exploitation and conservation of deposits and underground waters, and also for investigations of engineering-geological conditions. A harmonic development of the natural-cognitive assemblage of the Earth sciences connected with app lied and economic geology what is due to statutory foundations, ensures in suitable means for investigations and is a main factor that enables to receive good results of geological exploration works. A share of the institute in development of national economics is expressed by discoveries of deposits of mineral resources that form the basis for development of numerous industrial branches. Results of hydrogeological regional studies and investigations of restoration of underground water resources form also a very important achievement. These works gain a particular significance against common ecological impendency of waters. During reconstructing works and development of the country after the war, engineering-geological studies for large industrial objects as steelworks, electric power stations and hydrotechnical constructions have been of great importance. The most important achievements include unique in the world discoveries of copper ore deposits in the Lubin area, of native sulphur near Tarnobrzeg, of the Lublin Coal Basin and also of numerous deposits of brown coal, mine salt, polyhalites, zinc of numerous deposits of brown coal, mine salt, polyhalites, zinc and lead, titanomagnetites with vanadium, kaolin, barite and abundant deposits of rock materials. A resources basis of Poland is based on mineral raw materials located in over 4200 deposits, total resources of which exceed 205 mld tons. The analysis of values of exploited mineral products being subjected to international exchange proves that a total production value of the country constitutes 1% of the total world production and there-fore, Poland occupies the 22nd place in the world and 5th place in Europe. Abundance of the country in mineral products is larger than results from evaluation of the outpit as many resources (e.g. potash salts, some metal or chemical deposits) are not exploited. In spite of undoubted rich raw resources of Poland there are no sufficient deposits of natural oil and gas. These two products are the most valuable in the world production. If energetic resources are not taken into account (therefore also of the Polish hard and brown coals), then the value of the production of mineral resources puts our country at the 11th place in the world and the first one in Europe. A role played by the State Geological Institute in a discovery of these resources is undoubtful.

Application of the Engineering‐Geological Conditions in Land‐Use Plans in the Petrvald Region (Czech Republic)

AbstractThe objective of this paper is to demonstrate necessity to inform relevant parties about engineering‐geological conditions for various practical purposes, especially including appropriate land‐use planning. However, the relationship between relevant geological information and the geological environment is vital for foundation engineering purposes, especially where demanding structures are involved. This information is most conveniently structured when accumulated information concerning engineering‐geological zones is utilized. This necessarily includes knowledge of rock workability and also of the pre‐Quaternary bedrock, and these characteristics were then related to the current built‐up area and future development according to the land‐use plans in a case study are from the Petrvald Region (Czech Republic). The geological environment of area has been severely influenced by anthropogenic effects of deep black coal mining. Results of this research showed that future development should be founded on spoil banks, dumps, and settling basins. According to the land‐use plan, this zone occupies 44.9% of the area of interest, and its materials predominantly emanate from mining in the Ostrava–Karvina Coal District. For future foundation structures planned there, it is imperative to consult detailed engineering‐geological study. However, attention to and reliance on this necessity is not reflected in the existing land‐use plan.

Protection Control Scheme and Evaluation of Effectson Pipeline Crossing beneath Landslide Area

Long-distance natural gas transmission pipelines are planned to pass through the mountain area of midwest China, portions of which are threatened by severe landslide hazards. Therefore, the protection plan and control scheme for pipelines traversing and/or exiting landslide areas are of increasing interest and importance. A typical landslide in western China was used as an example to implement the strategy and evaluate the safety for a typical underground pipeline crossing the landslide area. The investigation and resulting control measures are based on the engineering geological study, and the numerical (finite-difference) interactive model of the pipeline and landslide, including the effect of soil arching. The effect of key design factors, including the spacing of antisliding piles, is determined by three-dimensional finite-difference numerical modeling. This technique also calculates the stability coefficient by use of the strength reduction method and calculation of stress and displacement fields. The results show that the recommended deployment of the antisliding piles can dramatically improve stability by reducing the effect of the landslide, thereby maintaining the displacement and stress of the pipeline within acceptable limits.

Engineering geological study of the second part of water supply Karaj to Tehran tunnel with emphasis on squeezing problems

This research is concerned with the assessment of squeezing potential along the second part of water supply Karaj to Tehran tunnel. One of the new components of water conveyance system in the north of Iran is the Karaj to Tehran water conveyance tunnel that has been excavated by a double shield TBM. This research has been performed on the second part of the tunnel with 14km long passes mainly through the pyroclastic and igneous rocks of Eocene age. The geological studies include field and laboratory investigations. Based on the results and for more exact investigation, tunnel alignment has been divided into 20 geological engineering units. Rock mass classifications have been performed for all units. Then, rock mass properties were calculated using empirical equations. Because of high overburden (up to 800m) and the presence of faults and crushed zones, it was necessary to evaluate squeezing potential along the critical section of the tunnel. Therefore, empirical and semi empirical approaches and a new method as critical strain have been used for evaluation of squeezing potential. Some experimental equations were used for estimation of critical strain and also Phase2 program has been used to calculate tunnel convergence. Consequently, squeezing index was estimated. This index is used for determination of squeezing degree. As a result, fair squeezing potential was found in crushed zones along the tunnel route.

Some observations about man-made features on natural terrain in Hong Kong

Much of Hong Kong is currently undeveloped and consists of vegetated, relatively steep hillsides, which are considered to be natural terrain. However, in many of these areas there is evidence in old aerial photographs of man-made features, which for the last 30–40 years or so have been hidden by dense vegetation. Before the 1970s the vegetation was considerably less dense than today and much of the ground surface was bare and clearly apparent. Preliminary study of old aerial photographs indicates some 10 types of man-made features, including agricultural, military, mining, prospecting, and other activities. Some are fairly recent, but relatively surprising is the widespread evidence of old to ancient land management practices, particularly on the more remote, elevated steep terrain away from existing villages. These features include stone walls, stone structures and a variety of stone terraces and unsupported earthen step-form terraces, some of which may have their origins with pre-Chinese aboriginal hill tribes. Their distribution, nature and occurrence provide an insight into the history of human settlement in Hong Kong, which is generally unknown within the earth science and engineering communities. These man-made features occur over extensive areas, with many on steep slopes and in natural drainage lines, and with some stone walls and agricultural terraces in excess of 3 m in height. These features should be recognized during natural terrain landslide hazard assessments and other engineering geological and geotechnical studies.

Current problems in the engineering-geological study of carbonate rocks in the territory of Moscow

A new approach to the study of carbonate rocks that takes stratigraphic sequences, cycles, and lithotypes into account is proposed. The main features of the geological structure of the model site in the territory of Moscow in accordance with the stratigraphic scheme are considered. In the considered section, the cyclicity in carbonate rocks is noted. In addition, the physical and mechanical properties of limestone and dolomite samples from the Neverovo and Shchurovo cyclites were studied on the basis of R. Dunham’s classification of carbonate rocks (1962). It was proven that the physical and mechanical rock properties are connected with rock lithotypes, which describe their inner structural morphology. In this case, regular changes in rock properties with depth are not noted, which can be associated with the position of the samples within the sequence. According to the results we obtained, the conclusion was made that it is necessary to compile an atlas-inventory of Carboniferous rocks for the territory of Moscow. For this purpose, the main key points for the implementation of this project are proposed.

A Comprehensive Approach to Investigate Maltese Coastal Landslides

SOLDATI, M., BONACHEA, J., BRUSCHI, M.V., CORATZA, P., DEVOTO, S., GONZÁLEZ-DIAZ, A., MANTOVANI, M., PASUTO, A., PIACENTINI, D., REMONDO, J and SCHEMBRI, J.A., 2011. A Comprehensive Approach to Investigate Maltese Coastal Landslides. In: Micallef, A. (ed.), MCRR3-2010 Conference Proceedings, Journal of Coastal Research, Special Issue, No. 61, pp. 472–473. Grosseto, Tuscany, Italy, ISSN 0749-0208.This paper presents geomorphological and engineering-geological studies carried out along the north-western coast of Malta by research groups belonging to the University of Modena and Reggio Emilia (Italy), the National Research Council (Italy), the University of Malta and the University of Cantabria (Spain). The research are funded by Fondazione Cassa di Risparmio di Modena and the European Centre for Geomorphological Hazards (CERG) and focus on the evolution of coastal landslides with emphasis on the issues of hazard and risk, with respect to the recreational infrastructures present in the area and to the several tourists that visit this stretch of coast.The area of study extends for about 12 km2 in Northern Malta and elevation ranges from the coast to about 110 m above the sea level. In this part of the Island, slope failures are abundant and strictly linked to lithological and structural factors. In fact, in the north-western area of Malta, between Paradise Bay and Gnejna Bay, three geological units outcrop that deeply control the morphological setting and the evolution of landscape: Globigerina Formation, Blue Clay Formation and Upper Coralline Formation. The Upper Coralline Limestone, the younger Formation of Malta Island, forms a karst plateau, bordered by vertical cliffs of varying heights, which ranges from a few meters to 30 m. At the foot of the limestone slopes Blue Clays Formation crops out which develops gently slopes that in some cases can reach directly the sea. The different mechanical behaviour of clays and limestone favours the development of lateral spreading phenomena, which occur in particular at Anchor Bay, at Ghajn Tuffieha Bay and along the western sector of Marfa Ridge. The occurence of this type of mass movement causes the presence of vertical joints and cracks near the calcareous slopes, due to the fragile response of rock material.Properties of the cracks, such as their aperture and persistence, depend on the different stages of lateral spreading phenomena; in the areas where the phase of evolution is more mature fractures reach lengths that can exceed 200 meters. A consequence of the presence of these wide discontinuities is the accumulation of large boulders along the coast, due to the detachament and fall of blocks from the vertical cliffs. The deposits are wide and the blocks are slowly scattered on the large terrace gently sloping towards the sea. In order to study and understand the complex evolution of coastal slope failures, a multidisciplinary approach has been applied and a complex system of monitoring has been installed. The research carried out so far has included a retrospective study of slope instability events along the north-west coast of Malta, collection and analysis of climatic data, multi-temporal analysis of aerial photos, geomorphological survey and mapping. In addition, the research plan foresees LIDAR surveys and radar interferometric analyses. The results obtained have permitted to outline the causes and evolution of coastal landslides in the north-western coast of Malta, with specific focus on rock spreading phenomena whose movement velocity and direction have been monitored since 2006 in two field sites. GPS network are located at Il-Qarraba and Anchor Bay. The analysis of monitoring data has shown that lateral spreading phenomena are active in both sites and that the displacements range from a few mm/yr to more then 3 cm/yr. The integration of new monitoring data to be acquired will permit the evaluation and mapping of landslide hazard. The final results of the research are aimin

Variations in the building site categories in the underground mining region of Doubrava (Czech Republic) for land use planning

In terms of demands and needs of ground investigation and foundation engineering, the engineering-geological conditions in the underground mining territories represent anthropogenically influenced areas in the most complicated manner, since they suffer the impacts from the underground mining of mineral resources. The subjects of observation are the so-called building site categories, which represent a certain risk factor that must be taken into consideration during foundation engineering and engineering-geological studies in the undermined territories. It is necessary to realise that underground mining is an anthropogenic geodynamic process which significantly varies over time due to mining change, and consequently with variations in the position, shape and size of subsidence in a subsidence basin. All the above mentioned variations should be mandatory knowledge for land use planners, engineering geologists, geotechnicians, foundation engineers and designers because of the evident logicality of these needs. This work presents a case study (Ostrava-Karvina Coal District in the north-east of the Czech Republic) of variations in the building site categories over time, and the results show that the chronology of the changes has a very significant influence in this area of interest. The results of the building site category evaluation imply that the majority of the interest area falls within relatively good conditions for founding all kinds of structures. However, it was then necessary to consider variations over time in the surface area of less suitable building site categories. A trend certainly confirmed the existence of the previously presumed mutual relationship between building site categories and subsidence size distribution. It is apparent from the analytic results of the relationship between building site categories and planned development that the negative impacts of mining have been only partly considered, or completely disregarded, in the development planning process. Consequently, future land use planners should carefully consider these particular building site categories as the most important and significant factors in the undermining of a region. In this manner, development can be successfully planned for present and future safety.

Engineering geological investigations for the foundations of large structures-examples of a concrete dam and a long bridge in Portugal

The safety of large structures requires adequate foundations, which implies a good knowledge of the geological and geotechnical conditions of the respective ground. In general, that is only possible through engineering geological studies which include proper site investigation techniques, adapted to the nature of the ground (rock mass or soil) and to the associated engineering problems. The paper illustrates the studies carried out for the design of the foundations of Ribeiradio 76 m high concrete gravity dam in a difficult rock mass and of Vasco da Gama Bridge, 13 km long, crossing the Tagus River in Lisbon, Portugal, through piles 75 m deep.

Geophysical exploration for a long deep tunnel to divert water from the Yangtze to the Yellow River, China

To identify problematic geological structures which would be encountered when driving tunnels in the high mountainous area of South West China, a joint geophysical and engineering geological study was made. The tunnels will form part of a project to divert water from the Yangtze to the Yellow Rivers. A controlled source audio-frequency magnetotelluric method (CSAMT) was carried out in 2004 between the Ma-ke and Jia-qu rivers in high, steep terrain. The paper discusses the method of data collection, processing, and analysis for the West route. The faults/fractures identified will need to be taken into account in the design and construction of the tunnel.

The use of the Ground Penetrating Radar (GPR) method in engineering-geological studies for the assessment of geological-cryological conditions

We present the results of the use of the Ground Penetrating Radar (GPR) method on saline and nonsaline soils in permafrost rock zones. GPR records are geologically interpreted during thermokarst and pingo study. The usefulness of the GPR method for mapping the top and bottom of permafrost rocks is explored for saline soils.

Undisturbed Strata Succession Sampling Technology and the Engineering Geological Characteristics of an Atoll in the Southern South China Sea

Coral reef calcareous sediment, a special category of rock-soil material, has representative geological structure and environmental characteristics. It is widely distributed in shallow areas of the tropical ocean; therefore the exploration instruments and technologies for engineering geology studies of coral reef calcareous sediments are very different from those used in land or deep-sea. Obtaining undisturbed cores from the Holocene unconsolidated stratum of coral reefs has been a key problem in the field of marine geology and environment surveying. The authors have designed a novel floating drilling platform equipped with a drilling machine, and successfully achieved undisturbed cores from both reef flats (with water depth 0.5 to 2 m) and a enclosed lagoon (with water depth 2–12 m) of Yongshu Reef (9°32–9°42 N, 112°52–113°04 E), southern South China Sea. Based on the detailed observation on the cores and the analysis from engineering geology, Yongshu Reef was split into reef three engineering geological zones: leading edge, reef flat (including outer reef flat, middle reef flat and inner reef flat) and lagoon. The sediments are classified in the stratum as fine sand, medium sand, coarse sand, gravel and weak-cemented reef limestone.