bluuebunny/crossref_metadata_2025_split huggingface dataset:
Geotechnical aspects of sabkha at Jubail, Saudi Arabia
Authors: James A. N. , Little A. L. 
Published: November 2007

Abstract
A large industrial complex was planned to be sited at Jubail on the Gulf Coast of Saudi Arabia. The sabkha here is essentially a near sea level, fiat area of fine grained soils, partially cemented by salt (sodium chloride) and calcium sulphate. Very little carbonate was found. The rest of the site was covered by sand dunes which, further inland, reached a height of 30 m.
The presence of artesian water, detected and measured at widespread locations, probably conducted through fissures in the underlying Hadrukh bedrock, was a particularly note-worthy feature of the area, having an important influence on the design of foundations and submerged structures of which examples are given. The artesian condition has been reported by a few observers for other sabkha areas. Jubail sabkha does not appear to conform in other ways with conditions at other sabkhas; for example, no traces were found of algal filaments, nor does it fit currently accepted ideas of formation or classification.
At Jubail, numerous site investigation boreholes were sunk to assist the design of installations. Measurements in many of these boreholes showed artesian heads, some up to 6 m or more above ground level in sabkha areas and up to 15 m above sabkha level in dune areas. Analyses have been developed in the paper to give rates of upward flow and limits of rise of artesian water in sabkha areas.
For construction reasons, sabkha was covered with 1.5 m to 3 m of compacted dune sandfill; further evidence for the underlying artesian condition was the discovery (predicted by the authors) of the rise of groundwater above the original ground surface and into sandfill. Calculations gave average rates of rise between 0.2mm/day and 1 mm/day. These artesian conditions are believed to receive a significant contribution from the sand dunes where high water tables have been recorded. Ideas have been put forward which could form a basis for a revised theory of the origin and continued existence of sabkhas at Jubail and at other similar locations.
The influence of artesian water on the design of installations at the industrial complex is discussed.
The estimation of rock rippability
Authors: MacGregor F. , Fell R. , Mostyn G. R. , Hocking G. , McNally G. 
Published: November 2007

Abstract
This paper presents the results of research into the rippability of rock by bulldozers carried out at the University of New South Wales. A database of detailed ripping and geological data gathered from highway and mine sites in New South Wales, Australia, has been used to determine the influence of different factors on the ripping productivity of bulldozers. The dominant factors affecting productivity have been found to be the unconfined compressive strength of the rock, the degree of weathering, seismic velocity, joint roughness and strength and the spacing of joints and bedding in the unripped rock, and bulldozer mass. The database has also been used to assess several commonly used rippability prediction methods. These are shown to be generally poor predictors of both ripping productivity and difficult ripping conditions. The forces involved in ripping have been measured in the laboratory on a quarter scale model of a tine, and in the field on an instrumented full scale tine, and the relationship between force and unconfined compressive strength and depth of penetration of the tine determined. Using this information, and a multiple variable regression analysis of the database, a method has been proposed for estimating productivity and for identifying difficult ripping conditions. This paper presents the method used to gather information for the database, the results of analysis of the database to assess the influence of individual factors on ripping productivity, a review of the available methods for predicting rippability, the results of multiple variable regression analysis, and the proposed prediction method.
Mechanism of creep in a volcanic saprolite
Authors: Irfan T. Y. 
Published: November 2007

Abstract
Clay mineralogy, mass structural features (e.g. relict discontinuities) and human activity all contributed to the initiation and retrogression of a creep-type instability in a saprolitic soil of volcanic rock origin at a landslip site in Hong Kong. Continuous creep resulted in the formation of a shear surface in the saprolite which then acted as a sliding surface when the slope was undercut. Shear zones have rarely been reported in saprolitic soils.
The morphology, geometry and kinematics of Judgement cliff rock avalanche, Blue Mountains, Jamaica, West Indies
Authors: Maharaj Russell J. 
Published: November 2007

Abstract

Judgement Cliff rock avalanche (JCRA) occurred during the latter part of 1692, during which 131-181 x 10
6
m
3
of faulted Miocene white limestone with chert nodules and minor sandstones and mudrocks, on a 38° overdip slope was detached on the eastern bank of the Yallahs River near Llandewey. The rock mass failed by a combination of sliding, free fall and toppling, impacted and disintegrated near the base of the original slope and flowed downslope subsequently damming the Yallahs River. Seismic loading followed by high water pressure in clefts are thought to be the main triggers for the event. The debris travelled horizontal and vertical distances of 1.763 km and 0.44 km respectively, accumulating over an area of 1.09 x 10
6
m
2
. The height/length and depth/ length values, hummocky surface topography and highly disintegrated nature of the deposit suggests that it was emplacement by flow of relatively dry debris.
The Franklands Village landslide
Authors: Morris Stevenson 
Published: November 2007

Between 23 December 1993 and 5 January 1994 a major landslip movement developed in Franklands Village which is situated on the eastern side of Haywards Heath, West Sussex. The approximate Ordnance Survey map reference is TQ 342/236.
The site of the landslide is set on the eastern slopes of a north-south trending valley. The existing development comprises blocks of two-storey fiats and semi-detached houses. The development for the Franklands Village Housing Association (FVHA) was constructed in the 1930s.
A development comprising a block of two-storey sheltered housing (Charles Bennett Court) was constructed by the Hanover Housing Association between 1991 and 1992, on the higher valley slopes to the southeast of the landslide.
Southern Testing Laboratories Limited (STL) were called in by Messrs K. A. Marshall & Partners, Consulting Engineers to the FVHA, to investigate cracking and foundation movement that had been developing in the Franklands Village properties during December 1992.
In general terms the valley slopes fall towards a small stream, towards the northwest at overall slopes of between 13 and 16° . Terracing, carried out to facilitate the initial development, steepened locally to between 30 and 45°. An investigation comprising hand-excavated trial holes, shell and auger boreholes (using a specially adapted restricted access rig), piezometers, slip indicator and monitoring of surface reference stakes, laboratory testing and geological and engineering analysis was undertaken by STL between January and April 1993.
The solid geology comprises the Upper Tunbridge Wells Sands at the crest of the slope, overlying the clays of the
An unfamiliar alkali-aggregate reaction from Trinidad
Authors: Eglinton, M. S. , Higginbottom I. E. , Pettifer G. S. 
Published: November 2007

Abstract
Blemishes rapidly developed on the surface of freshly poured structural concrete in Trinidad. The affected concrete was unsightly and suffered some loss of strength. Laboratory investigations showed that apparently inert natural sand and gravel aggregates used in the concrete were in fact coated or impregnated with an organic-iron complex which could be mobilized by cement alkalis to stain the concrete and retard the hydration of the surrounding cement. The reaction occurred when the total alkali content of the cement exceeded about 0.500y mass, expressed as Na~O equivalent. Lithologically similar aggregates from a neighbouring deposit were found to be predominantly non-reactive. When these were substituted for the original source, there was no recurrence of the problem. This paper describes the procedures which were used in the investigations, and discusses the character and occurrence of the alkali-reactive material. A simple test is suggested for the identification of aggregates which might react in this way. The authors are not aware of any published account of this reaction, although similar environmental factors might occur widely in tropical regions.
Technical Note Hydraulic conductivity of a tropical residual soil prone to landslides
Authors: Bronders J. 
Published: November 2007

Abstract

Saturated hydraulic conductivity or the coefficient of permeability (κ) of a residual soil prone to landslides was determined for a study area in Fiji. The techniques used were not new but the approach and the resulting κ-values may be useful for other studies (e.g. landslides). Inverse auger-hole tests are used to estimate κ-values. Tests conducted in sandy silty soils indicate values in the order of 10
-6
ms
-1
. No significant difference was found between calculated values at the surface and at 3 m depth. Infiltration tests showed saturated infiltration rates of 10
-5
ms
-1
.
Geotechnical properties of the Pleistocene clays of the Pappadai Valley, Taranto, Italy
Authors: Cotecchia F. , Chandler R. J. 
Published: November 2007

Abstract
This paper presents a set of experimental data that characterizes the Lower Pleistocene Pappadai Blue Clay in the Pappadai Valley, Taranto, southern Italy.
Basic geotechnical classification data are given, along with the results of chemical and mineralogical analyses which describe the variations of the properties of the clay for various vertical profiles through the deposit. These results reflect the near complete history of a sedimentary basin, add to the database for the blue clays of the Apulian Region, and provide a full description of the distribution of properties of a blue clay deposit. The variations of the properties of the clay can be related to the depositional history, to micropalaeontological studies, and to weathering process subsequent to deposition. The microstructure of the clay is studied using a scanning electron microscope.
Of particular interest are the relationships between the geological history of sedimentation, which is known with reasonable accuracy, and aspects of the mechanical behaviour of the clay.
Forms of hydraulic fractures created during a field test in overconsolidated glacial drift
Authors: Murdoch L. C. 
Published: November 2007

Abstract
Hydraulic fractures as long as 13 m were created at depths of 2 m in overconsolidated silty clay glacial drift during a field test using equipment designed to create hydraulic fractures in oil wells. The vicinity of each fracture was excavated, typically revealing a continuous fracture whose geometry was defined by four zones: a vertical fracture adjacent to the parent borehole; a flat-lying fracture in the vicinity of the borehole; a gently dipping fracture that assumes a preferred direction of propagation away from the borehole; a vertical fracture that intersects the ground surface. The hydraulic fractures were gently dipping with a preferred direction of propagation that apparently was controlled by loading of the ground surface; the fractures propagated away from a back hoe parked next to the parent borehole. Sand pumped into some of the fractures formed permeable layers that could increase flow into or out of low-permeability soils or rock, suggesting that sand-filled hydraulic fractures could have a variety of geotechnical or environmental applications.
The investigation of dissolution subsidence incorporating microgravity geophysics at Ripon, Yorkshire
Authors: Patterson D. A. , Davey J. C. , Cooper A. H. , Ferris J. K. 
Published: November 2007

Abstract
Dissolution subsidence affords some of the most difficult ground conditions with which engineering geologists have to deal. Within the UK, areas underlain by gypsiferous Permo-Triassic strata, most notably around Ripon in Yorkshire, are prone to dissolution structures and resultant building failures are well documented.
Conventional drilling of such unstable sites is often a ‘hit and miss’ affair and most geophysical techniques do not provide sufficient resolution to offer adequate confidence in the results. Proposals for the redevelopment of a site within the urban area at Ripon could not rely on such frequently inconclusive methods and it was necessary to implement a phased approach to site investigation. Following a desk study, high-resolution microgravity geophysics was carried out both inside and outside the existing building. This indicated a major negative anomaly of peak amplitude -74 μGal. Subsequent static core probing, rotary drilling and trial trenching confirmed the existence of a potentially unstable breccia pipe which could therefore be taken into account in the engineering design.
The genesis of the brown boulder clay of Dublin
Authors: Farrell Eric R. , Coxon Peter , Doff David H. , Prieďhomme Laurent 
Published: November 2007

Abstract
This paper presents the results of a study into the physical, chemical and mineralogical composition of two glacial sediments in Dublin, Ireland which are colloquially called Dublin ‘brown’ and ‘black boulder clays’. The objective of this study was to ascertain whether the ‘brown’ was formed through weathering of the ‘black boulder clay‘ or whether it represents a depositional feature. The study included fabric, clast lithological and microscopic analyses as well as X-ray diffraction. This work has shown that the sedimentology and fabrics of both are of the same glacigenic origin and that the lithology and mineralogy are identical apart from oxidation of the clay particles in the ‘brown’. It is therefore concluded that the ‘brown boulder’ clay arises from the weathering processes affecting the upper levels of the ‘black boulder clay’. This finding is consistent with the differences in the geotechnical parameters.
A geoteehnical survey of phase 1A of the Lesotho Highlands Water Project
Authors: Bell F. G. , De Graaf P. J. H. , Haskins D. R. 
Published: November 2007

Abstract
The purpose of Lesotho Highlands Water Project is primarily to supply water from Lesotho to the Pretoria-Witwatersrand-Vereeniging industrial region of South Africa. In addition, the hydroelectric scheme at Muela will supply enough electrical power to meet the needs of Lesotho.
The project consists of a number of dams, reservoirs and tunnels, and a hydroelectric scheme which will be constructed in four phases. Construction operations, if the project runs to completion, will last until around 2020. Phase IA commenced in 1987 and consists of the Katse Dam, a Transfer Tunnel from the impounded reservoir to Muela hydroelectric power station, the Muela Dam, and a Delivery Tunnel from the latter dam to the outfall on the Ash River, which is part of the Vaal River system. The tunnels total some 81 km in length.
The Katse Dam and Transfer Tunnel are constructed in the basalts of the Drakensberg Formation. Many of these basalts have been subjected to deuteric alteration and consequently contain expansive clay minerals. Their presence can mean that the basalts disintegrate rapidly on exposure, which has led to increased excavation at the dam site, and slabbing and spalling from the perimeter of the tunnel. The Delivery Tunnel South was constructed in sandstones of the Clarens Formation. These sandstones presented few problems during excavation and this tunnel was bored 20 months ahead of schedule. It was anticipated that the Delivery Tunnel North would be the most difficult to excavate as it runs through a succession of mudstones and sandstones. Hence this tunnel is being excavated by a double-shielded tunnel boring machine which can bore through varied ground and provide protection against rock falls, while simultaneously installing precast lining segments.
Effect of stiffness and amount of reinforcement on strength of sand
Authors: Al-Omari Raid R. , Nazhat Yahya N. , Dobaissi H. H. 
Published: November 2007

Abstract
High-quality geosynthetics of high-stiffness materials are being increasingly used in developing countries although they are not always readily available. An alternative approach in some situations is to use a larger amount of low-stiffness reinforcement. Triaxial tests have been performed on plastic mesh reinforced sand. The sand density, mesh stiffness and the number of reinforcing layers were varied. From these tests it was concluded that there may be a limiting reinforcement stiffness, influenced by the number of reinforcing layers after which there will he no further gain in strength. The density of sand reinforced using plastic mesh is found not to control strongly the strength. The results also revealed that the use of multiple layers of low-quality material can be more effective than the use of fewer layers of high-stiffness reinforcement.
Stabilization of an arid, saline sabkha soil using additives
Authors: Al-Amoudi Omar Saeed Baghabra , Asi Ibrahim Mohammed , EI-Naggar Zaghloul Raghib 
Published: November 2007

Abstract
This paper describes the results of an investigation on the effect of five stabilizing agents, namely limestone dust, marl, emulsified asphalt, cement and lime, on the properties of an arid, saline sabkha soil from eastern Saudi Arabia. Standard compaction and unconfined compressive strength tests were performed, the latter on wrapped specimens that had been allowed to cure for seven days. The results indicated that the density of sabkha mixtures could not be used as a primary criterion in any stabilization programme and the maximum strength of sabkha mixtures was attained at moisture contents much lower than the optimum. Despite the sabkha's coarsegrained nature, neither addition of marl nor of emulsified asphalt gave any significant improvement in the properties of sabkha and the effect of adding limestone dust was marginal. However, the addition of either lime or cement in the range of 2.5 to 100y weight of soil increased the strength between and 22 times.
Chalk fracture system characteristics: implications for flow and solute transport
Authors: Younger P. L. , Elliot T. 
Published: November 2007

Abstract
Bulk groundwater flow and solute advection occur in the fractures of the UK Chalk, and a knowledge of the frequency and aperture of these fractures is crucial to understanding these two key processes in the Chalk. Fracture frequencies in the Chalk of southeast England have been assessed regionally by means of outcrop scanline measurements. Measurements of radon dissolved in Chalk groundwaters allow the estimation of fracture apertures in the saturated zone. These data provide valuable controls on the conceptualization and estimation of hydraulic properties for the Chalk aquifer. In particular, standard hydraulic models of fractured rock permeability applied on the basis of these data are shown to be insufficient to explain the higher permeabilities measured in the unconfined Chalk beneath valley axes. In these settings, conduit flow mechanisms must be invoked; this in turn implies that modifications to standard matrix diffusion models are required to describe solute transport accurately.
Modelling of rising groundwater levels in the Chalk aquifer of the London Basin
Authors: Lucas H. C. , Robinson V. K. 
Published: November 2007

Abstract
The rising groundwater level in the confined chalk aquifer of the Central London Basin syncline has been the subject of study and concern for over a decade. Settlement effects in deep foundations and the flooding of tunnels are seen as the main problems arising from resaturation of the London Clay. The Thames Region of the National Rivers Authority has undertaken to formulate a strategy to monitor and control the rise in groundwater levels. Using a finite element, multi-layer computer model of the London Basin aquifer, various scenarios involving groundwater abstraction have been modelled and analysed up to the year 2040.
The objective of the study has been to optimize the location of potential groundwater abstraction points and the quantities pumped to provide the most effective control of regional groundwater levels. The water available is seen as a valuable resource for public water supply in an area where there is a demand deficit. The economics of utilizing this resource are complicated, however, by variations in water quality, the cost of treatment and the availability of lower cost water from other resources in some areas.
Statistical analysis of water table variations in Bahrain
Authors: Mahmood H. R. , Twigg D. R. 
Published: November 2007

Abstract
This paper reviews and discusses the factors causing the changes of water levels in the aquifers from which Bahrain extracts a large proportion of the water required for human consumption, agriculture and industrial use. These include noteonly geological and climatic features but also the effects of agricultural irrigation, coastal reclamation and leakages from the water supply network, sewer pipes and septic tanks. The results of statistical analyses carried out on water levels obtained from 125 boreholes over a 12-year period, in order to determine any underlying trends in water table movements, are presented and discussed. These analyses have shown that, in general, levels in the deeper aquifers are falling at rates ranging from 78 mm to 277 mm per annum. Variations in the near-surface aquifer are shown to be more complex but with the water table rising under areas associated with land reclaimed from the sea. If levels continue to rise at their present rate, the water table is predicted to be at or very close to the surface by the end of the century. This could lead to various geotechnical, structural, agricultural or health problems.
Hydrocarbon pollution control and remediation of groundwater: a brief review
Authors: Clark L. 
Published: November 2007

Abstract
Pollution of groundwater by petroleum products is widespread in the industrialized nations. Such pollution is likely to be found wherever petroleum products have been stored, used or refined. The scale of a pollution incident can, therefore, range from relatively minor beneath an oil storage tank to major beneath a refinery. The remediation of oil pollution is a large industry actively pursued by environmental agencies, oil users and the oil industry itself. There is a voluminous literature concerning such remediation, including manuals of remediation practice and environmental consultants' brochures. Unfortunately there is a paucity of published case histories of remediation programmes to show the effectiveness of various remediation practices. The remediation of pollution from a fuel spill at Heathrow is discussed and this, together with experience from other sites, is used to examine the cause and effect of such pollution incidents. The effect of the oil pollution, and the difficulty of remediation, vary with the location of the incident and the hydrogeological situation. The difficulty of remediation, for example, will increase with depth of the water table and with the proximity of urban areas. The possible strategies of remediation under various scenarios are discussed on the basis of experience in the investigation and remediation of oil pollution.