Engineering Geological Hazards Research Articles

Method of Evaluation for the Construction Geology of Transmission Line Based on Gray System Theory

A good engineering geological environment is the premise of engineering construction safety and security. The construction of transmission lines needs to take topography, stratigraphic lithology, engineering geological hazard, structural geology into consideration, but the survey personnel always judge the engineering geological environment roughly only based on individual subjective experience, personal professional level when selecting the transmission line route. We call this judgment process has a gray feature in the point of gray system, while the gray scale can be reduced by the calculation based on gray system, each factor play their role in the evaluation process in their respective weight, so the quantitative, clear results can be obtained. This paper constructs the index system of engineering geological factors of transmission line, using gray evaluation system, and with the help of AHP, the quantitative evaluation results are obtained, and provide a theoretical basis for geological environment evaluation of transmission line engineering. Finally, the geological evaluation is carried out by a real construction and realized the transformation of theory to tool.

ОЦЕНКА ИНЖЕНЕРНО-ГЕОКРИОЛОГИЧЕСКИХ УСЛОВИЙ БЕРЕГОВОГО НЕФТЕГАЗОКОНДЕНСАТНОГО МЕСТОРОЖДЕНИЯ

Актуальность исследования обусловлена необходимостью оценки существующих инженерно­геологических условий, процессов и опасностей, а также связанных с ними рисков и воздействий в отношении предполагаемого использования участка Берегового месторождения Пуровского района Ямало-Ненецкого автономного округа. Необходимым предварительным этапом при разработке проекта обустройства нефтегазоконденсатного месторождения является анализ данных территории строительства. Цель работы: построение карты инженерно-геологических условий территории месторождения для оценки состояния и прогноза изменений инженерно­геологических условий по результатам проведенных инженерно-геологических изысканий. Объектами исследования являются компоненты геологической среды, рассматриваемые при проектировании освоения Берегового месторождения. Методы исследования: анализ материалов инженерно-геологических изысканий, детальный литолого-генетический анализ территории, учет закономерностей пространственной изменчивости основных показателей инженерно­геологических условий (состав пород, температура грунтов, характер распространения многолетнемерзлых пород, инженерно-геологические процессы). Результаты. На основе дешифрирования космоснимка территории выделено шесть типов местностей: А (озерно­болотный); Б (хасырейный); В (приречный); Г (холмисто-увалистый); Д (линейно-грядовый) и Е (техногенные грунты). Результаты полевых работ и лабораторных исследований физико­механических свойств грунтов позволили детализировать предварительную оценку инженерно­геокриологических условий. Основная часть трассы проходит по приречному типу местности В. Наиболее неблагоприятными для строительства сооружений и прокладки трубопровода являются типы местности: А (встречается локально в низинах, представлен болотами с мощностью торфа до 2,2 м) и Б (имеет широкое распространение, представлен заболоченными участками, сложенными глинистыми грунтами с отсутствием поверхностного стока), типы Г и Д по трассе не встречены. По результатам выполненных работ рекомендовано размещать площадки строительства и трассы линейных сооружений на хорошо дренированных суходольных участках распространения талых грунтов.

Rockburst prediction in kimberlite using decision tree with incomplete data

Abstract A rockburst is a common engineering geological hazard. In order to predict rockburst potential in kimberlite at an underground diamond mine, a decision tree method was employed. Based on two fundamental premises of rockburst occurrence, σ θ , σ c , σ t , W E T are determined as indicators of rockburst, which are also partition attributes of the decision tree. 132 training samples (with 24 incomplete samples) were obtained from real rockburst cases from all over the world to build the decision tree. The decision tree based on 108 complete samples was built with an accuracy of 73% for 15 validation samples while another decision tree based on 132 samples (with 24 groups of incomplete data) shows an accuracy of 93% for validation samples. Hence, the second decision tree was employed for kimberlite burst prediction. 12 samples from lab tests and a numerical model were used as test samples. The results indicate a moderate burst liability which matches real situations at the diamond mind in question.

The deformation characteristics of saturated mucky clay under subway vehicle loads in Guangzhou

Since the long-term performance of subway tunnels is largely determined by the deformation of the soil around them, the study for the soil deformation characteristics under subway vehicle loads is important, especially in soft soil area. Based on a series of dynamic cyclic triaxial tests, the deformation characteristics of saturated mucky clay in Guangzhou were studied. The result shows that the failure cyclic stress amplitudes (CSA) and failure cyclic stress ratio occur when recoverable strain and accumulative plastic strain reaches approximately 0.22 and 15 %, respectively. Accordingly, the development of cyclic plastic strain is categorized into three types: steady state, rapid growth and instantaneous failure. When the stress level is below the failure CSA, the development of recoverable strain is nearly linear with accumulative plastic strain. To prevent and control engineering geological hazards induced by subway vehicle loads, vibration amplitudes of mucky clay around the subway tunnel axis must be closely monitored. More attention must be paid to soil deformation at the early operation stages of a subway line when mucky clay is sensitive to external loads. The strength of soil of the shallow ground should be considered as the basic parameters for study and design. The results of this paper can contribute to the design and maintenance of subway tunnels, as well as the prevention and control of tunnel axis deformation.

Hazards of mechanized tunnel excavation in H2S bearing ground in Aspar tunnel, Iran

Occurrence of hydrogen sulfide gas (H2S) is one of the most important engineering geological hazards during tunneling. Its hazards and consequent challenges are very difficult and costly to solve. During site investigation, one of the tasks for engineering geologists is prediction and evaluation of the risk of H2S gas in the underground spaces. In this study, water conveyance tunnel of Aspar, which was excavated in H2S-bearing environments, is discussed. The tunnel is excavated in the hydrocarbon formations. Applied experiments suggest that geological formations pertaining to hydrocarbon resources are crucial in formation and reservation of H2S gas. This paper briefly discusses hazards and geological sources of H2S, as well as remedial measures for decreasing the risks and problems in excavation of the tunnel. To predict the risk of H2S gas in the underground spaces, it is possible to use some precursors such as: sulfur springs, organic traces, organic argillaceous rocks, exposure of H2S odor from fresh surface of rock and smell of H2S during boreholes drilling. Controlling the inflow of groundwater into the excavation, diluting the concentration of H2S, training the personnel and utilization of some proper safety equipment have been used to mitigate risks and problems in tunnel excavation.

New rock stress factor for the stability graph method

A rockburst is a common engineering geological hazard. In order to predict rockburst potential in kimberlite at an underground diamond mine, a decision tree method was employed. Based on two fundamental premises of rockburst occurrence, σθ,σc,σt,WET are determined as indicators of rockburst, which are also partition attributes of the decision tree. 132 training samples (with 24 incomplete samples) were obtained from real rockburst cases from all over the world to build the decision tree. The decision tree based on 108 complete samples was built with an accuracy of 73% for 15 validation samples while another decision tree based on 132 samples (with 24 groups of incomplete data) shows an accuracy of 93% for validation samples. Hence, the second decision tree was employed for kimberlite burst prediction. 12 samples from lab tests and a numerical model were used as test samples. The results indicate a moderate burst liability which matches real situations at the diamond mind in question.

Engineering-geological hazards and management in the Mountain Crimea coastal zone

The main engineering-geological hazards and their factors of the Mountain Crimea coastal region are considered. A characteristic shore line site of Cape Kikineiz and its neighboring coastal area near the Katsiveli settlement has been studied in more detail. The important characteristic of the site is a high diversity of geological conditions with numerous manifestations of dangerous engineering-geological processes: shore and hydrological network abrasion, loss of slopes and rocks stability, etc. These processes have intensified during the last decades under the influence of natural and man-induced factors. The results of preliminary study of geo-environmental situation of the area are presented. The program for further research and possible recommendations for rational coastal hazard management and area ecological state improvement are outlined.

Integrated evaluation on highway engineering geological hazard in mountainous area of Enshi, Hubei

Aiming at the geological features of highway engineering in mountainous area of Enshi, Hubei Province, the principles to set up an integrated evaluation system for highway engineering geological hazard are formulated. Then, the integrated evaluation system for highway engineering geological hazard in mountainous area of Enshi is established. In the evaluation system, the first-level evaluation indices are geological development degree, geological conditions, and damaging power, whereas the second-level indices including key factors affecting main kinds of geological hazard. Meanwhile, the borders of indices are determined. At last, the method of Fuzzy Comprehensive Evaluation (FCE) is adopted to quantitatively evaluate the highway engineering geological hazard in mountainous area of Enshi.

Landslide hazard evaluation in and around the Ilam Hydropower Project, Eastern Nepal Himalaya

The paper describes the results of the engineering geological and landslide hazard evaluation studies carried out in and around the Ilam Hydropower Project, eastern Nepal. Various types of mass wasting phenomena such as gully erosion, bank undercutting, and landslides are observed along the Mai Khola, Puwa Khola and road corridors. Gully erosion and bank undercutting are common on the slopes adjacent to streams and gullies. Most of the landslides are located on the slopes of 25° to 40° whereas large rock falls are found on the slopes, which are steeper than 40°. South-facing dip slopes contain large landslides while north-facing slopes seem to be relatively stable. The population of translational slide is dominant in the study area and is found mostly on soil having a depth of 3-6 m. Most of the rock falls are confined in schistose gneiss and highly fractured quartzite. Generally, three sets of joints govern the failure pattern of rockslides. The main triggering factors for mass movement of the area are high intensity of rainfall, rock discontinuities, steep topography, poor vegetation and river scouring. Land use pattern of the area has also equally contributed to initiate the mass movements in the area. The high hazard zones for rock slopes were confined to the steep dip slopes with highly fractured rocks whereas soil slope hazard is confined to fault zones and south facing slope. The soil slope was found to be more hazardous than the rock slope. The main causative factors for the landslide hazard in the study area are steep slope, rock discontinuity, land use pattern, soil depth and rainfall.

Engineering Geology and the Environment: Proceedings of the 8th International Conference of the IAEG, Vancouver, British Columbia, Canada, 21–25 September, 1998

Moore, D. & Huyr, O. (eds) . Balkema, Rotterdam, 1998. 387 hardback, 6 vols, 5000pp. ISBN 90-5410-990-4. The proceedings are published in six volumes, although the sixth was not available at the time of this review. The first five volumes are divided into eight sections according to their subject matter: special session on Canadian geology (4 papers); new developments in site investigation (72 papers); engineering geology and natural hazards (121 papers); engineering geology and the environment (65 papers); construction materials (28 …

Geologic hazards of an embankment dam constructed across a major, active plate boundary fault

Abstract The geological structures associated with the site of the 55 million m 3 Karameh embankment dam constructed in the Jordan Valley and the tectonic effects on dam foundation and reservoir margins were reviewed. The dam crosses the strike-slip fault of the Jordan Valley Rift Zone. Trace evidence of the fault indicates a displacement of 8 to 15 m over a rupture length of some 130 km, which probably took place several centuries ago. Earthquakes with Richter magnitudes as great as 7.8 have occurred along the Jordan Valley Fault. Deterministic studies by Tapponnier (1992) indicated that the dam design should incorporate the possibility of a 7.8 event, a maximum horizontal rupture displacement on the fault of 10 m and a design peak ground acceleration (PGA) of 0.74 g at the site of the dam. These values are consistent with those which would be used in the USA for a similar case. However, the dam was actually designed by a consultant and constructed for a PGA of about a quarter of this value, based on seismic hazard analysis following guidelines of the International Committee on Large Dams (ICOLD) (1989). Moreover, the dam was designed for displacements of 6 m horizontal and 2 m vertically. Liquefiable sand layers were found in the dam foundation. A PGA of 0.50 g will trigger liquefaction of the sand layers in the dam foundation which would be expected to result in a crest settlement of 4.4 m. Slope stability analysis indicated deep failure planes in the foundation zone. The excavation of loose materials from under the dam foundation has not precluded the possibility of liquefaction occurring under the expected earthquake. Field mapping of geological features during the dam foundation excavation and construction revealed that: a) the most likely location of the Jordan Valley fault is in the area where the Wadi Mallaha stream crosses the dam axis, b) zones of en echelon type open fissures have been defined in the laminates sub-parallel to the Jordan Valley Fault Zone, c) at the Wadi Mallaha stream bed a parallel zone of faulting and warping of the Lisan Formation was identified, and d) the alignment is clearly confirmed by the exposure immediately upstream of the core at Ch 1375. The main wrench fault zone crosses the embankment footprint (upstream to downstream approximately) and reaches the surface around Ch 1375. The critical safety elements of the embankment are the core, the downstream fine filter, the chimney drain and the drainage blanket. To resist large earthquake events safely, the following safety measures should be implemented: 1. A freeboard of 7.0 m instead of the 5.0 m constructed. 2. The foundation of the dam should be stabilized against liquefaction. 3. The embankment internal zoning should be designed to accommodate damage resulting from earthquake events with a magnitude of 7.8. 4. The foundation needs relief measures downstream to lower the pore pressure. This paper describes the measures taken during construction as overall defense against future fault movements through a wide plastic core, an extensive upstream blanket, a 5.0-m thick downstream chimney filter and drain zones, a 5-m freeboard and an upstream crack stopper zone which may be critical for normal faults with a lateral extension component. The geological determination of the main wrench fault alignment resulted in the addition of an extra 2-m width to each of the already wide chimney filter and drain zones. In order to reduce potential seepage, local cut-off trenches or slush grouting were used for treatment of any open fissures at the upstream edge of the external blanket and the right bank ridge. The scale and scope of this dam and inherent engineering geological hazards are unprecedented. The design is considered deficient. This paper documents serious safety issues with the dam. The constructed dam presents serious safety risks and represents a case history of a disaster waiting to happen.

Present situation of the research and application of engineering multiwave seismic prospecting in China

In four aspects, which are the leading exploration of mine and tunnel; engineering geological hazard prospecting and engineering shock resistance; non-destructive testing of engineering quality; the measurement of rock physical properties, this paper gives a detailed summary and some comments on the present situation of the research and application of the ideas, theories and methods of engineering multiwave seismic prospecting. The content includes: the prospecting of coal field caved pillar, underground gallery, underground cavity and the fault ahead of tunnel; the exploration of earth surface Karst collapse, active fault, and shock resistance of underground lifeline engineering; the dynamic non-destructive testing of quality and bearing capacity of pile foundation, the non-destructive testing of strength, thickness and defects of concrete pavement, and the non-destructive testing of submarine tunnel engineering quality; the measurement of rock physical properties under high temperature and high pressure and the determination of physical properties of irregular rock samples. Some existing problems are discussed and the direction which should be developed in the future is proposed.

Engineering geology of North Lantau, Hong Kong

Abstract Results of an engineering geology study of the northern part of Lantau Island in the west of Hong Kong are described. Over the next few years this area will be subject to major changes as a result of the planned new international airport at Chek Lap Kok. As a consequence of the airport, high-speed road and rail links are also planned along the coast of North Lantau, together with two new towns, industrial developments and a major port development at the eastern end. The study identified specific engineering geological problems and hazards with major safety or economic implications for the planned developments. The western end of the island is mostly rugged mountainous terrain with elevations rising to more than 900 m above sea level. Towards the east, the topography is more subdued, although hillslopes are generally still steep. The solid geology of the area is dominated by volcanic and intrusive igneous rocks of Mesozoic age, including volcanic tuffs and lava, granites and quartzphyric and feldsparphyric rhyolite dykes. These have weathered and a mantle of saprolite and residual soil covers much of the terrain. The onshore superficial soils include colluvium and alluvium whilst offshore, thick deposits of Holocene marine muds and Pleistocene alluvium overlie the weathered bedrock. The main geological and geotechnical constraints to development on land in the North Lantau area are: the possible adverse effect of relict joints on the stability of cut slopes, potential stability problems on natural slopes due to steep, colluvium covered slopes, boulder fields and the possible remobilization of colluvium within drainage courses during rainstorms. Difficulties may also be encountered with piled foundations due to the presence of large boulders in deposits of alluvium and colluvium. Offshore, the presence of thick deposits of compressible marine mud represents the main difficulty for the planned reclamations along the coastline.

Engineering Geology, and Seismic and Volcanic Hazards in the Hijaz Railway Region--Syria, Jordan, and Saudi Arabia

Research Article| August 01, 1987 Engineering Geology, and Seismic and Volcanic Hazards in the Hijaz Railway Region—Syria, Jordan, and Saudi Arabia REGINALD P. BRIGGS REGINALD P. BRIGGS Geomega, Inc., P.O. Box 13127, Pittsburgh, PA 15243 Search for other works by this author on: GSW Google Scholar Environmental and Engineering Geoscience (1987) xxiv (3): 403–423. https://doi.org/10.2113/gseegeosci.xxiv.3.403 Article history first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation REGINALD P. BRIGGS; Engineering Geology, and Seismic and Volcanic Hazards in the Hijaz Railway Region—Syria, Jordan, and Saudi Arabia. Environmental and Engineering Geoscience 1987;; xxiv (3): 403–423. doi: https://doi.org/10.2113/gseegeosci.xxiv.3.403 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu nav search search input Search input auto suggest search filter All ContentBy SocietyEnvironmental and Engineering Geoscience Search Advanced Search Abstract A new standard-gauge railway from Damascus, Syria through Jordan to Medina, Saudi Arabia is under consideration by these three countries. The Feasibility Study for the railway, done in 1980, has been received favorably, though no further action is likely till the Iraq-Iran war is resolved. Three alternative routes were investigated, with potential system lengths, including branches, ranging from 1,621 to 1,701 km. The total length of corridors studied, without repetition of segments common to more than one, is 3,047 km. With a strip width of about 25 km, the area of geology treated at scale 1:250,000 thus was more than 75,000 km2. Engineering and other characteristics of the rocks were tabulated. An excerpt from this large geologic map and part of the engineering-geology table are included here.In the Hijaz Mountains of Saudi Arabia, bedrock largely is metamorphosed Precambrian volcanic and plutonic rock. Paleozoic sandstones dip northeastward from the Hijaz into southern Jordan. Central and northern Jordan chiefly exposed Cretaceous and Tertiary marine strata. Extensive Tertiary and Quaternary basalt fields are common in northern Jordan and southern Syria and overprint the Precambrian and Paleozoic terrain in the Hijaz Mountains. There are large intermontane plains in the Hijaz and sporadic coastal plains along the Red Sea. Water supply for the project is problematic.Tectonically, the region is dominated by the Red Sea graben and Dead Sea rift. The rift in particular is seismically active, so seismic risk is a factor in railway design. Volcanic eruptions are as recent as about 1850, and renewed activity is a possible, if remote, hazard to the proposed railway. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not currently have access to this article.

Engineering geology hazards of rock glaciers : Giardino, J R; Vick, S G Bull Assoc Engng GeolV22, N2, May 1985, P201–216

Engineering geology hazards of rock glaciers : Giardino, J R; Vick, S G Bull Assoc Engng GeolV22, N2, May 1985, P201–216

Identification and evaluation of geotechnical hazards : Oborn, L E Proc of the Symposium on Engineering for Dams and Canals, Alexandra, 24–27 Nov 1983V9, N4, P9.1–9.14. Publ New Zealand: Inst Prof Engr New Zealand, 1983

The New Zealand landscape presents a wide range of engineering geological hazards which investigators, designers, constructors and operators of hydro structures have to overcome. These hazards are a legacy of the country's complex geological history and its present seismotectonic and volcanological setting. These hazards include those that have resulted from the effects of past geological events and processes and mans activities (such as slope instability, large-scale loss of water and small-scale piping, subsidence and collapse of the ground's surface, and collapse of man-made underground openings), and those from events that can be expected some time in the future, but for which the place, timing and severity cannot be predicted on present day knowledge (such as strong earthquake induced ground motions, active faulting, ground deformation and volcanism). Investigations should be designed to identify and evaluate all hazards that could pose a threat to a project. This requires relevant regional and site engineering geological and engineering studies using conventional or appropriate engineering, geological, geomechanical, geophysical and geodetic techniques. These activities should be co-ordinated by a team of engineers and engineering geologists who have a deep sense of involvement, responsibility, and professionalism.

The Engineering Geology Hazards of Rock Glaciers

Rock glaciers are common, yet, because of the association with past periglacial and glacial activity, are often ignored as present day engineering hazards. As alpine development increases, rock glacier location and analysis becomes vital. Air and ground reconnaissance easily identifies rock glaciers using four characteristics: 1) slope angle somewhere between that of the adjoining rock face and the valley floor below; 2) surface of coarse rock fragments; 3) little or no surface vegetation; and 4) concave-upward slope profiles in the upper parts and strongly convex fronts. Active rock glaciers are best avoided because of rock glacier movement and ice melting and subsidence. Inactive rock glaciers may be built on or excavated depending on the presence of clear ice layers in the rock glacier and the amount of risk engineers are willing to assume. On inactive rock glaciers containing only interstitial ice, permafrost construction techniques may be effective.