Showing papers in "Bulletin of the International Association of Engineering Geology in 1985"
TL;DR: In this paper, the relation between mass movements, rainfall and interstitial pressures is examined to evaluate the relations between mass movement, rainfall, and the interstitial pressure in rock slides and earth slides.
Abstract: Old landslides in precarious conditions and new masses are moved or removed by particularly heavy rainfalls. Phenomena relative to rock slides and earth slides are examined to evaluate the relations between mass movements, rainfall and interstitial pressures.
77 citations
TL;DR: In this article, a scheme used to characterise the weathered rock mass and describes the engineering geological logging of the large diameter pile foundations on a deeply weathered granodiorite for a series of bridges in the New Territories, Hong Kong.
Abstract: In weathered rocks the determination of founding depth for the foundations of major structures is complicated by the highly variable nature of the material. In order to ensure that the properties of the soil or rock mass on which the structure is to be founded correspond to those assumed in design it is necessary to unambiguously characterise the mass. This paper outlines a scheme used to characterise the weathered rock mass and describes the engineering geological logging of the large diameter pile foundations on a deeply weathered granodiorite for a series of bridges in the New Territories, Hong Kong. The results of field and laboratory index and engineering tests carried out to determine the characteristics of the foundation rock are discussed. The drawbacks of use of RQD, percentage core recovery or probing tests as a means of determining and proving founding depth of piles are also discussed.
47 citations
TL;DR: In this article, nine stages of weathering of a porphyritic biotite granite bedrock material have been distinguished on the basis of differences of colour, texture and the extent of alteration of mineral grains.
Abstract: Nine stages of weathering of a porphyritic biotite granite bedrock material have been distinguished on the basis of differences of colour, texture and the extent of alteration of mineral grains. Determination of the distribution pattern of the different stabes of weathering of bedrock material within the weathering profile then allowed for recognition of six stages of weathering of the bedrock considered on the scale of the mass. Characterisation of the weathering profile over the prophyritic biotite granite bedrock thus involved recognition and definition of weathering of the bedrock, both on the scale of the hand specimen, i.e. as rock material, and on the scale of the mass, i.e. as rock mass.
40 citations
TL;DR: The point load test, developed over the last two decades, provides a practical and cheap method for laboratory or field determination of rock strength as mentioned in this paper, which is corrected to a standard thickness of 50 mm and the resultant I(50) values may be used to estimate uniaxial compressive strength.
Abstract: The point load test, developed over the last two decades, provides a practical and cheap method for laboratory or field determination of rock strength. Because of the size dependence of the test, results are corrected to a standard thickness of 50 mm and the resultant I(50) values may be used to estimate uniaxial compressive strength.
18 citations
TL;DR: In this article, the shear strength characteristics of a fine grained amphibolite derived laterite soil within an area of one square metre in the same horizon was investigated by means of consolidated undrained triaxial compression tests.
Abstract: Variability in the shear strength characteristics of a fine grained amphibolite derived laterite soil within an area of one square metre in the same horizon is investigated by means of consolidated undrained triaxial compression tests.
8 citations
TL;DR: In this paper, the authors proposed a method for soil structure estimation in SEM enabling to obtain quick and reliable quantitative structure characteristics of small size samples (≈0,5 cm3).
Abstract: The present structure estimation methods are rather long-termed and expensive; moreover, they are sometimes impossible to use in reason of difficulty of sampling large sized specimens. The soil structure estimation in SEM enabling to obtain quick and reliable quantitative structure characteristics of small size samples (≈0,5 cm3) are becoming very important at present. SEM investigation of identical areas on both conjugated surfaces of sample fracture, total binary SEM image with real structure of undisturbed sample, discrimination and digitization of the image and its processing by computer with specially designed algorithms is the core of this method. The quantitative structure analysis is made practically instantly and the following data may be obtained: the number of pores and particles, average perimeter, square and radius of pores and particles, porosity, specific surface, pore shape index, the number of contacts between particles, pore and particle distribution according to the sizes. The quickness and reliability of the results obtained as well as the application which enables to cover all kinds of soils is an evident advantage of the method. The most important factor is the tracing of soil genesis and the nature of the strengths.
8 citations
TL;DR: In this article, a new volumetric strainmeter system was developed for the measurement of true volusetric strains occurring in selected fresh and decomposed rock samples tested under computer controlled triaxial loading conditions.
Abstract: A new volumetric strainmeter system has been developed for the measurement of true volumetric strains occurring in selected fresh and decomposed rock samples tested under computer controlled triaxial loading conditions. The system is capable of resolving volume adjustments of the confining medium to within ±2.8 mm3 and maintain confining pressure deviations to ± 6.9 kPa. The results of the investigation have shown the inadequacy of the commonly used strain gauge method to represent the volumetric strains occurring in the whole of the test specimen and they have provided further experimental evidence for the continuity concept in the fracture mechanism of rocks. Even in the most decomposed samples tested, crack initiation and propagation starts at lower stress levels than previously recognised, in contrast to the generally accepted concept of critical stress levels which characterise and define the process of brittle fracture propagation in rocks.
7 citations
TL;DR: In this article, it is suggested that the Unified Soil Classification System should be extended to accomodate these new classes of soils, based mainly on the presence and quantity of gypsum or carbonate.
Abstract: Calcareous and gypsiferous soils from semi arid Australia have been studied. The geotechnical properties are greatly influenced by the presence of an appreciable proportion (approximately 20%) of carbonate and gypsum. The particle size distribution and the Atterberg limits do not supply reliable information for the proper identification and classification of these soils. Their classification should therefore be based mainly on the presence and quantity of gypsum or carbonate. It is suggested that the Unified Soil Classification System be extended to accomodate these new classes of soils.
4 citations
TL;DR: In this paper, a tentative tentative en choisissant des caracteristiques qui prennent en compte les conditions aux limites des sols constitues a la fois d'elements grossiers and d'une fraction fine.
Abstract: L'elaboration d'une classification des sols, fondee sur un petit nombre de coefficients est toujours delicate. Nous avons fait une tentative en choisissant des caracteristiques qui prennent en compte les conditions aux limites des sols constitues a la fois d'elements grossiers et d'une fraction fine.
3 citations
TL;DR: In this article, the authors studied some of the variations and suggested that there is enough reason to consider the time-dependent variations in site investigation and design practice in the tropical situation.
Abstract: Site investigation for rock slope design in Ghana has been based on experience from temperate areas of the world. Tropical weathering causes variation in engineering properties with time. This paper studies some of the variations and suggests that there is enough reason to consider the time-dependent variations in site investigation and design practice in the tropical situation.
3 citations
TL;DR: In this article, static-dynamic probing carried out in sandy soils of varying genesis and age is discussed, and a great similarity has been found in the natural compaction of these sediments.
Abstract: Results based on static-dynamic probing carried out in sandy soils of varying genesis and age are discussed. On the basis of site investigations carried out on the Holocence and Pleistocene terraces of the rivers Vistula and Odra, in delta formations and in the fluvio-glacial Pleistocene deposits of the upland, a great similarity has been found in the natural compaction of these sediments. Sand layers in loose condition were foundm reaching a depth of less than twenty metres in the Holocene sand formations, and down to 10 or 12 metres in the Pleistocene deposits.
TL;DR: In this article, the authors used model simulation techniques to investigate the stress-strain characteristics of a composite rock mass and established a relation between strength reduction and the presence of weaker components and the inclined discontinuities in the composite.
Abstract: Precambrian layered rocks consisting of quartzites, phyllites and metagreywackes of the Aravallis having a large variation in thickness, petrographic and strength characteristics constitute the foundation of the Kadana dam on the River Mahi, Gujarat, India. The nearly vertical formations are grouped into blocks and are considered as a composite rock mass system. Model simulation techniques were utilized to investigate the stress-strain characteristics of this composite rock mass. A relation has been established between strength reduction and the presence of weaker components and the inclined discontinuities in the composite. The experimentally determined values of the uniaxial compressive strength and the static modulus of elasticity of the models are compared with their values obtained by theoretical calculations and the ratio is termed “composit efficiency”. The “composite efficiency” when multiplied by those theoretical values of the prototype composite yield the estimated composite values of compressive strength and elastic modulus of the prototype. This method has shown that the strength deformation conditions of foundation rocks of a complex nature, differing both in lithology and structure, can reasonably be predicted from the model simulation studies. Such data are of immense value in the design of an engineering structure.
TL;DR: In this paper, les auteurs decrivent deux applications de l'analyse de la fracturation dans deux secteurs limites du bouclier arabe.
Abstract: Apres un bref rappel theorique des caracteristiques des zones de cisaillement, les auteurs, decrivent deux applications de l'analyse de la fracturation dans deux secteurs limites du bouclier arabe:
- le site de la vallee de Wadi Aridah, ou la realisation d'un barrage est en projet;
- le site d'Umm Hadid, ou une campagne de prospection miniere a ete menee.
TL;DR: In this paper, the authors describe the geodynamic evolution of the Corinthian graben with its successive enlargement and show the contribution of the tectonics, lithology and particular ground foundation conditions in the distribution of the seismic intensities.
Abstract: The 1981 seismic paroxysm of the Corinthian gulf was well inside the framework, of the geodynamic evolution of this graben with its successive enlargement The serious damage, the surface rupture and the secondary effects defined a seismic area of an E-W general direction, which coincides with the main tectonic axes The contribution of the tectonics, lithology and particular ground foundation conditions in the distribution of the seismic intensities has been clearly shown, after recording the damage, on the geological-tectonic map of a wider area and in maps, at a scale of 1∶2000, of four villages destroyed
TL;DR: In this paper, the authors present an analysis of the relationships deterministes ou probabilistes liant the evolution of a processus d'origine soit profonde (seismicite, deformations tectoniques, reajustements isostatiques, volcanisme, diapirisme), soit superficielle (alteration, erosion, sedimentation).
Abstract: Tout site de stockage de dechets nucleaires est soumis a une evolution naturelle inevitable dependant de son contexte geodynamique (s.l.). Cette evolution est sous le controle de processus d'origine soit profonde (seismicite, deformations tectoniques, reajustements isostatiques, volcanisme, diapirisme), soit superficielle (alteration, erosion, sedimentation). Les premiers sont a replacer dans le contexte geotectonique regional et global; les seconds sont conditionnes par les variations climatiques a toutes echelles. Les interferences entre les parametres, directes ou detournees; sont nombreuses. Elles peuvent aboutir a un renforcement ou a un affaiblissement de la barriere naturelle de protection. L'analyse qualitative et quantitative des divers facteurs et de leurs interactions conduit a l'elaboration de scenarios d'evolution. Its prennent en compte les relations deterministes ou probabilistes liant les processus. Les donnees chiffrees sont exprimees sous forme de fourchettes, ponderees, et injectees dans le modele. Celui-ci constitue un canevas assez vaste pour etre raffine ou simplifie en fonction du degre de complexite voulu. Cette prospective est menee sur plusieurs intervalles de temps: 0 a+3 siecles, 0 a + 104 ans, 0 a 105 ans. Elle est appliquee, a titre d'illustration, a un cas reel.
TL;DR: The Federal Capital Territory (FCT) of Nigeria is underlain by crystalline igneous and metamorphic rocks of Precambrian age as mentioned in this paper, and the most conspicuous structural features are a broad J-shaped fold traversing the eastern and central part of the territory and a north-trending shear zone along the eastern boundary.
Abstract: The 7,700-km2-area Federal Capital Territory, Nigeria, is underlain by crystalline igneous and metamorphic rocks of Precambrian age. Sandstone and claystone of Cretaceous age overlie Precambrian rocks in the southwestern part of the Territory. Laterite caps many hills of Cretaceous rock, some hills of Precambrian rock, and crops out near stream banks in the east and northeast. The most conspicuous structural features are a broad “J”-shaped fold traversing the eastern and central part of the Territory and a north-trending shear zone along the eastern boundary. The soils of the Territory are lateritic and belong to the SW-SP-SM (Unified Soil Classification System) groups covering Precambrian migmatites gneisses and granites and the SC group covering Cretaceous sediments and Precambrian mica-rich schists. The average penetrometer shear strength of the soil is 3.11 bars. The engineering characteristics of the rocks are (1) medium- to high-strength massive and gneissic rock, (2) low-to medium-strength bedded rock, and (3) low-strength foliated and sheared rock. An area of at least 800 km2 is free from apparent geological hazards and should be suitable for construction of a capital city, its environs and supporting facilities.
TL;DR: In this paper, le geotechnicien dispose d'une panoplie assez large de methodes confortatives, allant du simple renforcement local au remblayage integral.
Abstract: Sur le territoire francais, plusieurs milliers d'exploitations partielles par chambres et petits piliers abandonnes ont ete recensees. Ces anciennes exploitations, essentiellement de pierre de taille, sont aujourd'hui abandonnees et dans un etat de conservation extremement variable. En zone urbaine, elles menacent directement la securite des personnes et des biens, et doivent etre confortees. Le geotechnicien dispose d'une panoplie assez large de methodes confortatives, allant du simple renforcement local au remblayage integral. Nous nous interessons plus particulierement ici au methodes confortatives de l'element de base, le pilier, telles que le remblayage, le boulonnage, le cerclage et la projection de mortier ou de resine. Des experimentations en laboratoire ont montre que ces methodes ont toutes pour effet de confiner le pilier en bloquant partiellement les deformations laterales. L'analogie avec l'essai triaxial classique s'arrete la car la loi de comportement du materiau constitutif du pilier ne peut pas etre extrapolee au systeme composite pilier-confortement.
TL;DR: The landscape environment is presently formed by the system in which there are natural, as well as anthropogeneous components as discussed by the authors, and the possibility and method of construction of a technical work depends on specific natural conditions.
Abstract: The landscape environment is presently formed by the system in which there are natural, as well as anthropogeneous components. There is natural direct and inverse relation between them. The possibility and method of construction of a technical work depends on specific natural conditions. Of decisive influence are mainly the rock relief, groundwater and geodynamic processes, which Matula (1976) terms the main components of the engineering geological environment.
TL;DR: In this article, the authors deal with the different types of microstructure of discontinuity fillings and show the influence of different fillings on the stability of galleries in granitoides, gneisses and Lower Carboniferous sediments.
Abstract: Rock mass classification and the rock stability with respect to tunnels and underground openings depends usually not only on the petrology of the rock but also on the rock discontinuity analysis. The article deals with the different types of microstructure of discontinuity fillings. The microstructure of quartz and calcite of hydrothermal origin and tectonic clays as well as the slickensides in them were verified by means of SEM and by X-ray analysis. The examples of the influence of different discontinuity fillings on the stability of galleries in granitoides, gneisses and Lower Carboniferous sediments are also presented.
TL;DR: In this paper, the authors present a cartographie geotechnique of the region couverte, les proprietes majeures, telles the teneur en eau naturelle, resistance au cisaillement, sensibilite, le rapport de surconsolidation, lindice et le rapport of compression des depots argileux.
Abstract: Dans le contexte d'une cartographie geotechnique, il est essentiel de connaitre les facteurs geotechniques, lesquels influencent directement les sols et les structures que l'on y erige. L'etude presente, resume pour la region couverte, les proprietes majeures, telles la teneur en eau naturelle, la resistance au cisaillement, la sensibilite, le rapport de surconsolidation, l'indice et le rapport de compression des depots argileux.
TL;DR: In this article, le role of facteurs geologiques semble moins preponderant que celui des facteur geometriques et mecaniques in the stabilite of carrieres souterraines.
Abstract: La stabilite des carrieres souterraines est difficile a evaluer a moyen et long terme. Dans le but de connaitre les factuurs et d'expliquer les mecanismes qui sont responsables de son evolution, nous avons entrepris l'etude du role des phenomenes exogenes, des heterogeneites et des discontinuites du milieu et du mat⪻riau dans 4 carrieres souterraines de la Gironde (France). En nous appuyant sur l'analyse statistique des donnees, nous avons mis en evidence le role preponderant de la porosite et de la teneur en argiles dans le comportement mecanique du calcaire. A l'echelle de la carriere, le role des facteurs geologiques semble moins preponderant que celui des facteurs geometriques et mecaniques. C'est toutefois en les prenant en compte que l'on peut parvenir a une bonne comprehension du comportement du materiau vis-a-vis des phenomenes de fluage et de fatigue, dont le role semble, primordial dans la stabilite des carrieres souterraines.
TL;DR: The authors tire quelques enseignements generaux sur les types de mouvements de terrain survenus depuis 1930 sur les versants des collines de la Ville de Lyon (France).
Abstract: Cet article tire quelques enseignements generaux sur les types de mouvements de terrain survenus depuis 1930 sur les versants des collines de la Ville de Lyon (France). Ces mouvements sont superficiels et concernent des terrains naturels ou rapportes, retenus par des murs de natures diverses. Le role des eaux de pluie ou provenant de canalisation rompues est preponderant. Les mesures preventives appliquees sont exposees et discutees.
TL;DR: Les sediments de la riviere Grande-Baleine furent deposes dans une eau saumâtre, environ 7,000 years as mentioned in this paper.
Abstract: Les sediments de la riviere Grande-Baleine furent deposes dans une eau saumâtre, il y a environ 7 000 ans; la salinite n'etait pas moins de 8 g/l. Ces depots argileux ont ete souleves plus de 150 m au-dessus du niveau de la mer. Le sol est extremement sensible (St plus grand que 200 tel que mesure au cone suedois). L'indice de liquidite est souvent au-dessus de 2. A l'oedometre, ce sediment est tres compressible et presente un rapport de surconsolidation de plus de 2 et ce, avec peu de signes d'erosion. Les travaux de recherche ont donne un modele qui comprend differents processus tels que: une cimentation precoce durant ou tot apres la deposition et le lessivage jusqu'a l'actuelle salinite interstitielle de 0.5 g/l. Les deux procedes ont resulte en un sediment a une teneur en eau anormalement elevee (par rapport aux contraintes effectives) et un indice de liquidite eleve du en partie au lessivage. Des travaux sur le terrain et en laboratoire ont demontre que les processus responsables de la structuration de ce sol sont le lessivage et la cimentation (ou quoi que ce soit qui ait empeche ce sol de se consolider completement). Aucune evidence n'a pu etre trouvee qui suggererait l'action du processus de consolidation retardee. Aujourd'hui, ce sol est geologiquement normalement consolide (i.e. aucune erosion ou surcharge), et physico-chimiquement sous-consolide (i.e. une teneur en eau plus elevee que celle normalement retrouvee pour une meme pression sur un sol resedimente).
TL;DR: In this paper, geophysical, seismic and geoelectric investigations were carried out in the Messara district Crete, in order to determine the bedrock structure for the construction of a dam.
Abstract: Geophysical, seismic and geoelectric, investigations were carried out in the Messara district Crete, in order to determine the bedrock structure for the construction of a dam. The geophysical measurements resulted in the following experiences of probable universal validity for similar problems: seismic refraction measurements discover excellently the thickness and nature of the uppermost weathered zone. Electric measurements, however, throw light on the presence or absence of faults, breaks, with a high degree of certaity. The electrical measurements have also been proved more convenient for the acquirement of lithological composition data of the compact-bedrock, because they can distinguish between clay and sandstone formations.
TL;DR: Deccan volcanics cover vast areas of the subcontinent in parts of Central and Western India as discussed by the authors and these volcanics exhibit considerable variations in their overall charaterictics and mineralogy, which influence their engineering geological behaviour.
Abstract: Deccan volcanics cover vast areas of the subcontinent in parts of Central and Western India. These volcanics exhibit considerable variations in their overall charaterictics and mineralogy, which influence their engineering geological behaviour. Presently the Decan volcanics are being thoroughly investigated for their mass characteristic properties. The massive basalt flows are identified as belonging to Pahoehoe and Aa types. In the western margin of the Trap region trachytes, pyroclastic beds intertrappean sedimentaries and bole layers are interbedded with the flows, besides numerous intrusive dykes. Soil profiles of varying thicknesses have developed in different parts. At many places, the surficial deposits include bauxites, laterites, alluvium and recent deposits.
TL;DR: In this paper, the authors present the requirements of the highest construction and technological requirements in building the large pumped-storage systems, the considerable functional variety of their individual components, as well as their mutual interactions, create the necessity of an extremely responsible selection and evaluation of suitable engineering geological environments.
Abstract: The highest construction and technological requirements in building the large pumped-storage systems, the considerable functional variety of their individual components, as well as their mutual interactions, create the necessity of an extremely responsible selection and evaluation of suitable engineering geological environments. Of a great influence are mainly the lithological diversity and tectonic disturbances involved in the rock mass environments and the effects of the geodynamical phenomena (neotectonic activity, rock mass movements, etc.). The best understanding of geological conditions is of primary importance mainly in the first stages of investigation and site selection.
TL;DR: In this paper, a detailed estimation of engineering-geological properties of building soils should comprise the problems arising from specific features of these soils, especially if they are the so-called weak soils.
Abstract: A detailed estimation of engineering-geological properties of building soils should comprise the problems arising from specific features of these soils, especially if they are the so-called weak soils. Besides, engineering-geological research tends to be improved and the criteria are defined to expect the general features of soils in certain geological environments, that is in definite areas. During the present investigations fluvial flood deposits, muds, were examined. They are considered as weak soils and their unfavourable properties result from numerous factors: slight diagenesis, high moisture and considerable lithological variability. Holocene and recent muds were examined, coming from the valleys of the Vistula and the Odra as well as of their tributaries. Engineering-geological properties of muds were found to depend on lithology reflecting the conditions in the valley and the drainage basin during deposition. The following parameters were found to be the most significant: grain size composition (clay fraction in all soil types and sand fraction in not very cohesive soils), conten of organic matter (over 1 per cent), moisture, and, from the parameters that describe the soil state, liquid limit to reflect the physico-chemical properties of muds and their activity to water. The results obtained and recorded relationships should be applied among others during the preparation of maps and in engineering-geological regionalization of river valleys.
TL;DR: The legal and environmental principles that form the base of present and possibly future legislation and administration are described in this paper, and some problems are discussed and in particular that of legal retro-responsibility for wastes.
Abstract: Legislation and administration of waste disposal is primarily a State and Local Government responsibility in Australia. The legal and environmental principles that form the base of present and possibly future legislation and administration are described. Some problems are discussed and in particular that of legal retro-responsibility for wastes. New South Wales and Victoria have different legislative and administrative systems. Both are complex with many overlapping Acts.
TL;DR: The Love Canal hazardous waste site in New York State, U.S.A. became a benchmark for negative feelings towards the siting of future hazardous waste landfills and facilities as mentioned in this paper.
Abstract: During the late 1970's the Love Canal hazardous waste site in New York State, U.S.A. became a benchmark for negative feelings towards the siting of future hazardous waste landfills and facilities. At the present time social and political factors often dominate the siting process. There is growing anxiety being shown by the public about the location of waste facilities, and especially for hazardous materials. There are repeatable socio-political patterns associated with siting events and disposal agencies need to identify the appropriate «cast of characters» in the siting «play». There is an increasing need for the communication of disposal information to the community as well as their inclusion in the decision making process. More sympathetic consideration needs to be given to compensation strategies.