bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of a dynamic penetrometer as a ground investigation and design tool in Hertfordshire
Authors: Huntley S. L.
Published: April 2008

Dynamic penetrometer testing offers considerable practical advantages over conventional ground investigation techniques; however experience with the method is very limited, and correlations with other exploratory methods have not been made available in the UK literature. The technique is much more widely used in Europe. A Swedish Dynamic Sounding apparatus is described, and some examples of the successful applications of the technique in Hertfordshire are described. Use in design of the penetration resistance values obtained from the test are hampered by the absence of a mechanical classification system for soils commonly encountered in the United Kingdom. The results of a large number of investigations in East Anglia during the period 1983–1988 have led to a tentative classification system for cohesive soil, granular soil and chalk, which may be used for correlation with geological materials in adjacent boreholes.
The use of Swedish ram sounding and weight sounding in residual soils and weathered rocks
Authors: Pitts J.
Published: April 2008

During a series of investigations involving residual soils and weathered rocks in Singapore, correlations have been established between weight sounding test resistance (WST), ram sounding test resistance (RST) and the standard penetration test (SPT) resistance. Equality of blow counts between SPT and corrected RST is suggested for values of
N
less than 30. Above that, SPT blow counts were consistently higher, and a value of
N
SPT
= 1.5
N
RST
was more typical. Weight sounding results have also been found to correlate well with SPT blow counts.

The soil type aand the shape of tips used in each test are considered important in explaining the trends of the correlation curves. In sandy soils or soils with a low clay content, the dynamic friction is negligible. In stiff to hard cohesive soils, plugging of the SPT samples and dynamic friction effects on the interior of the tube may explain the high SPT blow counts compared with those from RST.

The main disadvantage of using ram and weight sounding methods rather than the SPT is that samples are not usually recovered. However, each provides continuous profiles of penetration resistance measured at closer intervals than SPT, both quickly and economically without a borehole.
Field testing of lime sediments and the interpretation of test data
Authors: Lewandowska Jolanta
Published: April 2008

The paper presents the results of field investigations comprising static cone penetration tests (CPT) and dynamic soundings using a probe with a vane tip which enabled shear strength testing. The tests were carried out on lime deposits, the material concerned being a waste product obtained in soda production and stored in large yards. The correlation between the cone resistance (
q
c
) and the undrained shear strength (
s
u
) has been studied, showing some scattering in the cone factor (
N
k
) and a mean of 20.
Geotechnical properties of soft clays from the Witch Ground Basin, central North Sea
Authors: Paul M. A. , Jobson L. M.
Published: April 2008

The Witch Ground Basin to the northeast of Peterhead is occupied by Late to Postglacial clays which reach a maximum thickness of over forty metres. High resolution seismic surveys have shown that the Sediments can be divided into two stratigraphic units on the basis of their acoustic signatures: the upper Witch Ground Formation shows in its lower part a finely detailed pattern of laterally continuous multiple reflectors, whereas the lower Swatchway and Coal Pit Formations present a disorganised signature in which few reflectors are continuous.

Profiles of bulk density, water content and undrained shear strength have been obtained from two continuously sampled, adjacent boreholes which penetrated the sediments to a depth of forty metres. These show that the deposits of the Witch Ground Basin comprise a single geotechnical unit with the properties expected of a fine grained sediment of glaciomarine origin. The principal geotechnical properties change gradationally as a result of changes in composition and from selfweight compression. The different seismic signatures on which the basin stratigraphy is based are not reflected by major geotechnical changes within the sediment, but may well result from secondary features of the geotechnical profile.
Waste disposal site selection techniques in Quaternary terraine Ontario, Canada
Authors: Cooper A. J.
Published: April 2008

Thick and predictable deposits of fine grained Quaternary materials have been used for the siting of waste management facilities in Ontario. The search for such sites is founded on the application of techniques in Quaternary geology and hydrogeology. Two examples are presented. Oxford County is located southwest of Toronto in an area of parallel morainic ridges separated by flat till plains. Conventional wisdom would focus on the till plains for thick, consistent fine grained Quaternary Sediments. However, the careful analysis of the Quaternary stratigraphy and glacial history revealed that better sites are located along the moraines. A site on the Ingersoll Moraine was studied in detail and defended at a public hearing. Concerns about the geology of the materials were allayed by the confirmation of homogeneous clayey silt materials exposed when the site opened in late 1986. A much wider ranging search was undertaken for a major hazardous and liquid industrial waste treatment and disposal facility for the Province of Ontario. Progressively more detailed investigations of the Quaternary geology were used to assist a multi-disciplinary site selection team. Initial interpretations covered an area of 75 000 km
2
at a scale of 1:250 000. Eight candidate sites were then selected for further investigation with five continuously sampled stratigraphic boreholes. The chosen site is located in a depression in the bedrock filled with 40 m of glaciolacustrine clayey silt. Site specific hydrogeological and geotechnical studies were integrated with a detailed geological investigation.
Groundwater in the Quaternary deposits of Scotland: a valuable resource and a potential engineering hazard
Authors: Robins N. S. , Ball D. F.
Published: April 2008

The Scottish Quaternary strata contain a wide range of lithologies with an equally wide spectrum of hydrogeological properties. The more permeable material contains valuable groundwater resources which increasingly are being exploited for rural and island communities. However, the common juxtaposition of high and low permeability strata, the occurrence of confined groundwater in clay-capped gravels, and the risk of ground subsidence due to dewatering, together provide a range of potential Engineering problems and hazards.
Lateral stress measurements in a glaciomarine silty clay
Authors: Sully J. P. , Campanella R. G.
Published: April 2008

The paper presents the procedure used for installation of spade-like total stress cells (TSC) in an overconsolidated silty clay and subsequent interpretation of the data obtained. Prior to installation, all the spade cells were calibrated in the laboratory for both pressure and temperature effects. After extraction from the ground, the stress cells were recalibrated and changes in the calibration characteristics were noted. These changes presumably result from the effects of installation. The stress cells were read over a period of three months. The measured stresses, pore pressures and temperatures are evaluated to provide a profile of the lateral stress coefficient for the site.
The influence of changes in sea level on coastal cliff instability in Devon
Authors: Kalaugher P. G. , Grainger P.
Published: April 2008

Major variations in sea level have resulted from climatic changes during the Quaternary. In addition, beyond the maximum limit of glaciation, periglacial climates in southern Britain have produced Quaternary deposits which can affect the nature of coastal slopes and their response to marine erosion. Examples are given of cliffs in head (solifluction) deposits which overlie raised shore platforms in Devon. The present styles and distribution of coastal landslide hazards, recorded in recent surveys, are directly related to past Quaternary sea levels and climatic fluctuations. Future trends in relative sea level are a significant factor in the determination of the hazards in the longer term, as there could be changes in the level at which marine erosion is effective. Rankings of the hazards, which should in any case be updated routinely by repeated monitoring of the landslide activity, ought to reflect expected changes in sea level.
Report on Session 2b
Authors: Petley D. J.
Published: April 2008

Introduction

No part of geological time has had a more profound influence on the engineering characteristics of soils and rocks than the Quaternary period. Large areas of the earth’s surface are covered by superficial deposits of Quaternary age, and almost all surface soils and rocks affected by the changeds in climate which occurred in the Quaternary retain characteristics which have implications for engineering works at the present time.

During the Quaternary period, at least five major glaciations occurred. During each glaciation, as the climate became colder, ice sheets spread from the poles and mountainous areas, to be followed by a retreat as warmer weather conditions prevailed during the inter-glacial periods. At the present time, in the Northern hemisphere, ice sheets cover approximately 10% of the total land area, but during the time of maximum glaciation in the Pleistocene, over 30% of the total land area was covered by ice.

The volume of water taken up by the ice sheets caused significant variation in sea-levels. It has been estimated that the maximum and minimum sea-levels during the Quaternary were +200 m and -150 m 0D respectively. Indeed, following the main postglacial transgression at the end of the Devensian, the sea has been within 3 m of its present level for only the last 4000 or 5000 years. These large variation in sea-level significantly influenced the development and stability of slopes in coastal areas and inland.
Glacigenic soils of the Taff Valley, South Wales: their geomorphology, geology and engineering properties
Authors: Lewis J. D.
Published: April 2008

The paper identifies the relationships that exist between glacigenic soils at the limits of glaciation, their landforms and engineering properties, using as a type example the predominantly granular soils of the Taff Valley.

Local and regional models of glacial and periglacial process Systems derived from engineering geomorphological mapping provide a means for optimizing site investigation design and practice. The models improve efficiency in delineating sample localities, aid the genetic Classification of the soils and assist with the specification of in situ and laboratory testing programmes to ensure maximum cost effectiveness.

By the application of Standard geological and geotechnical methods and techniques the soils are shown to exhibit textures, fabrics and ranges of engineering properties developed due to specific modes of genesis and post-depositional history. Consideration is given to dominant modal fractions and to the likely effect these have on the mass behaviour the soils.
Distribution and verification of Quaternary deposits in the Cairo Area
Authors: El-Sohby M. A. , Mazen S. O.
Published: April 2008

In previous research studies, the combined impact of the morphology of the surface, the River Nile and its changes, and the geological, environmental and historical development in the Cairo area, were considered. As a result, characteristic regions of soil formations were identified and classified by their origin, and their distribution produced on maps.

In present research work, the authors have examined a large number of borehole records to verify the previous Classification. These boring records were simplified and subsoil section drawn at different locations.

It was found that the simplified borehole records and subsoil sections are in complete agreement with the distribution of soils based on their origin. Thus, typical profiles representing classified types in Cairo area could be drawn and related to the stratigraphical sequence.

In order to fully appreciate the nature of alluvial and deltaic deposits in the Cairo area, important physical and mechanical properties of each sublayer of the defined soil formations were determined. This was done on the basis of soil mechanics test results of natural samples.
The geophysical investigation of Quaternary geological environments
Authors: Penn S.
Published: April 2008

There is a considerable Variation in the lithology and thickness of glacial and fluvial Sediments in Western Europe. This wide range of materials is associated with significant engineering problems and considerable economic interest from the extractive industries.

Geophysical techniques are widely applied to map and investigate areas with glacial deposits and fluvio-glacial sands and gravels. There are sheet-like outwash deposits, some with buried and therefore unpredictable Channels, and smaller fissure and pocket deposits in rock. An assessment of the geometry of a deposit can be accurately achieved with geophysical methods, and electrical techniques have been particularly successful. The nature of the deposit, layering within the deposit, lateral Variation of lithology, thickness and depth to bedrock may all be established quickly and with great cost effectiveness.

Numerous other problems occur with Quaternary environments particularly alteration and contamination of rock masses. Electrical techniques are also a powerful investigative tool in these situations.

The success of these techniques depends upon the geophysical properties of the material to be investigated and the geophysical properties of the underlying sediment or bedrock, the technique actually selected, professional field practice and interpretation. These factors will be discussed and illustrated with reference to a number of case studies.
An evaluation of seismic and borehole data available from onshore and offshore site investigations of relict glaciated areas
Authors: Stewart F. S.
Published: April 2008

Using late Quaternary ice marginal sites from the North Sea and Iceland a comparison of the sedimentary information available from subaerial and submarine site investigations was made. This was with regard to palaeo-environmental reconstructions of ice marginal Sedimentation processes. A detailed high resolution seismic survey in-the North Sea was compared to a similar subaerial site in Iceland. Submarine cores were compared with logged sections available from cliffs. These comparisons highlighted the differences in resolution of the structural information available and also the problems of applying existing modeis of glacimarine Sedimentation to offshore sites. This has raised questions concerning the accuracy of reconstructing palaeo-environments and processes in offshore sites presently under investigation. The implications of this for engineering projects in offshore areas requiring very precise site information about relict glaciated areas are significant.
Protection of the Pleistocene Sediments along the rim of the San Jacinto reservoir in Bolivia
Authors: Clarke I. D. , Roose K. , Riemer W.
Published: April 2008

Quaternary tectonic and volcanic activity, and glaciation, have created conditions in the Andes which have complicated the engineering of many dams. A notorious feature often encountered is the “paleocauce”, a former river bed blocked during Quaternary times and now filled with thick sediments, subsequent erosion having formed a new, displaced river bed. In many cases more severe problems have been caused by the presence of a paleocauce, particularly when this was only detected at an advanced stage of studies, than have arisen from the damming of the new river course,

The paper describes a particular problem which arose during design of the San Jacinto project in southern Bolivia, and was due to the dispersive character of the Pleistocene deposits filling the paleocauce of the river Tolomosa.

To fully evaluate the phenomenon of dispersivity, the Standard “pinhole test” has to be per formed, in conjunct ion with two other tests, on a large selection of samples. The results of these tests on samples from San Jacinto suggested that Classification diagrams for dispersive soils may have to be modified from case to case to reflect specific properties of the soil of the respective sedimentary facies.
Engineering geological aspects of the Quaternary deposits of an urban area in southwest Greece
Authors: Constantinidis C. V. , Sabatakakis N. , Tsiambaos G.
Published: April 2008

The paper presents the successive stages of the methodology which has been adopted for the interpretation of findings of an extensive geotechnical site investigation. This investigation was carried out in the urban area of the town of Kalamata, S.W Greece subsequent to the catastrophic earthquakes which occured in the area during September 1986. The scope of the wqrk was to determine the engineering geological characteristics of Quaternary deposits which mainly constitute the foundation materials beneath Kalamata, so that the various geotechnical groups could be presented in terms of consistent contour maps and cross-sections. To this end 25 boreholes were drilled to enable geotechnical profiling at several sites in the area of interest. Apart from borings, some 90 cone penetration tests (C.P.T.) were performed by using a mobile truck-mounted electronic cone penetrometer system with a capability of 200 KN. The cross-hole seismic technique was also used in certain boreholes to estimate Shear wave velocities (Vs), in the ground. Finally, a detailed laboratory Programme was carried out to determine the geotechnical parameters necessary for the grouping of soils in relation to their engineering behaviour.
Full scale trials of grid-reinforced soil foundations on alluvium
Authors: Jones R. H. , Lee R. G. , Dawson A. R.
Published: April 2008

Much undeveloped, low cost land is underlain by recent deposits on which development is inhibited by high foundation costs. A typical example is an industrial estate at Newport, Gwent, which is underlain to a depth of 8m by alluvium (clays, silts and peat) overlying Glacial Till and Mercia Mudstone. The superficial deposits are relatively soft and foundations are normally piled, thus increasing the overall cost of each structure by about £60/m
2
. Grid reinforced soil-foundations, in which trenches are backfilled with compacted clay or granular fill reinforced with layers of plastic coated welded wire mesh, were proposed as a possible cheaper alternative. Full scale instrumented trials have been undertaken at the Newport site to assess the viability of such foundations. The grid reinforced clay foundation which was loaded over a 5 year period proved unsuitable but information relevant to embankments was obtained. On the other hand granular soil foundations have shown considerable promise. Under a loading of approximately 300 kPa, the unreinforced foundation failed but the reinforced one was still serviceable. Thus the system was capable of achieving an allowable bearing pressure of at least 100 kPa and appears a viable and economic method of founding on sites underlain by soft Quaternary deposits.
A precompression method of soft ground improvement using dewatering
Authors: Kotera H. , Sakemi T. , Matsui T.
Published: April 2008

The background and geology of the Tokyo Bay area of Japan, and recent soil improvement methods used in Japan are described. The vertical drain method has frequently been used to improve thick quarternary deposits in this area. This paper describes a case history of a dewatering method in combination with the vertical drains and preloading in a major soft ground improvement project in the Urayasu area of the Tokyo Bay. The dewatering method is a vacuum consolidation method, which is tentatively applied to the soft clay ground.

In the combined dewatering method, the waterhead in a vertical sand drain is lowered by pumping the water from a sand layer within or below a soft clayey layer using deep wells. The dewatering applies negative water pressure to the soft clayey layer, promoting its consolidation.

The authors confirm the consolidation effect of the dewatering and establish the applicability of the combined dewatering method to the soft clay ground.

It is concluded that the dewatering method described significantly increases the shear strength and the consolidation yield stress of the soft clayey layer.
An investigation of the Nanyang swelling clays
Authors: Liu T. H. , Yan X. K.
Published: April 2008

Swelling clays are widely distributed in the area to the south of the Fu-Niu Mountain Range, in the Nanyang Basin, Henan Province, PRC. The clays are damaging to buildings, railways, highways, and hydraulic structures, due to their unusual properties. This paper presents some results of studies on Nanyang Clays based on site investigation and engineering practice. It describes the formation and distribution, mineral composition and cation exchange, structural characteristics, the shrinking and swelling index, the Variation of strength related to dimension effects, anisotropy, gradual reduction, cycling of expansive and shrinking and time effect.
Contractor-designed piles for the Toyota car plant in Derbyshire
Authors: Houston C. R. M.
Published: April 2008

The problems encountered in the interpretation of site geology, the selection of design parameters, and the design and performance of precast and continuous flight auger piles are considered for the contractor-designed piled foundations to the Toyota car plant in Derbyshire. Of approximately 2000 piles, about 800 precast and bored piles were installed as contractor-designed.

The complex geology of the site consists of Mercia Mudstones to the north and west, glacial clay deposits to the south and a fluvio-glacial channel running diagonally across the site. The site is further complicated by areas of cut and fill operations. The design of the piles was based entirely on penetration into either the glacial clays or Mercia Mudstones. The parameters for these materials were derived from comprehensive site investigation by over 150 boreholes. The performance of contract piles was proved by a series of pile tests.
Potential construction problems for bridge foundations in areas underlain by a complex marble formation in Hong Kong
Authors: Irfan T. Y.
Published: April 2008

Complex and varied geological conditions were encountered during the site investigation for a number of bridge foundations along the proposed route of a trunk road between two new towns in the North West New Territories of Hong Kong. Special care is needed in the construction of the deep foundations for these bridges, particularly in areas underlain by a marble formation which has a varied karstic surface underneath a thick superficial cover and locally contains solution features, including
large cavities. Foundation conditions are further complicated by varying lithology, weathering, dyke intrusions and the related alterations and thrust faulting.
Estimation of grout take for small-scale developments in areas of shallow coal mining: some examples from the East Pennine coalfield
Authors: Lloyd P. J. , Cripps J. C. , Bell F. G.
Published: April 2008

Large areas of the coalfields of the UK are underlain by ground from which coal has been formerly mined by shallow pillar and stall methods. At present the condition of these workings varies. In many the roof rocks above stalls have collapsed, giving rise to void migration and areas of disturbed ground. As such they pose a hazard to surface land use due primarily to the upward migration of voids and the compression of disturbed ground. Subsidence due to pillars punching into the roof or floor measures and occasional pillar collapse may also occur.

Before construction work can be carried out in such areas it is normal practice for the condition of the ground to be investigated and appropriate action taken if old mine workings are present. In the case of small-scale developments, for example low rise housing, this must be carried out within tight budgetary constraints. In such projects the presence and character of adverse features are usually determined by open-hole rotary drilling. Treatment, if needed, consists of backfilling with cement-sand-pulverized fuel ash grouts.

The problems experienced in investigating the presence and effects of shallow mining in the context of housing developments are considered. As the cost of treatment is strongly influenced by volumetric grout take, methods of estimating this quantity are reviewed. Various predictive formulae have been proposed; the efficacy of these is considered with reference to appropriate examples from the North Derbyshire and Yorkshire coalfields.
Foundations in Gault Clay
Authors: Marsh A. H. , Greenwood N. R.
Published: April 2008

Aspects of Gault Clay geology are reviewed with particular reference to engineering characteristics and a qualitative engineering geology assessment scheme for Gault Clays in foundations is presented. Geotechnical parameters including index, strength and compressibility properties are summarized. Results from a full-scale foundation load test in weathered Gault Clay are analysed. Site investigation techniques for Gault Clays are discussed and some of the most appropriate methods identified.
Aspects of highway rock engineering in the UK
Authors: Matheson G. D.
Published: April 2008

Aspects of highway rock engineering relating to excavation and slope stability, with emphasis on the evolution of successful design and construction techniques in the UK, are considered.

Early techniques for highway rock excavation were labour intensive and time consuming. New techniques of drilling and blasting, introduced in the 20th century, dramatically increased the ease with which rock could be excavated. However, these new techniques considerably damaged the host rocks, adversely affecting face stability and increasing the requirements for remedial work and maintenance. Effective rock engineering techniques have now been developed for designing slopes in harmony with the geotechnical environment and for harnessing the power of high explosives without imparting damage to the design slope. Such techniques include the optimized design technique and presplit blasting, important aspects of which are described.

Aspects other than final face stability must be taken into account when designing a rock excavation. These include the environmental impact and the possible requirements of new contract procedures such as design and build.
Design and construction of an embankment incorporating polystyrene and geogrid reinforcement
Authors: Campton A. L.
Published: April 2008

An 800 m long and 5 m high acoustic bund has been successfully constructed along the top of the A3 trunk road cutting in London Clay near Guildford, Surrey. The bund generally comprises geogrid reinforced fill with slopes of up to 60°. In an area of sheared and fissured London Clay the bund incorporates polystyrene fill, from a level of 1.0 m below the original ground level, to prevent any surcharging of the top of the cutting. Polystyrene was also used as a backfill material to a retaining wall positioned in the middle of the bund to prevent settlement of an adjacent structure. The choices of materials, the design procedures and the methods of construction are considered.
Rock engineering for Dundee Inner Ring Road
Authors: Davies T. P. , Smith T. J.
Published: April 2008

Stage XII of Dundee Inner Ring Road runs through a built-up part of the city of Dundee and includes a 145 m long cut and cover tunnel and a 355 m length of road in vertical open cut with retaining walls. Excavations extended 14 m below the level of adjacent ground. During construction, disturbance to nearby buildings and services had to be minimized; close attention was paid to the stability of the excavations and the selection of excavation techniques. This paper presents an outline of the site geology, describes the approach to geotechnical investigations and highlights certain aspects of design and construction, particularly the stabilization of the sidewalls and the role of detailed geotechnical mapping.

The route runs within a Devonian age sandstone-mudstone-shale-basic lava sequence dipping at 20 to 30 degrees. Historically, stability problems have occurred in these formations in the Dundee area. Site investigations included inclined coring to clarify the disposition of faults, exploratory trenching, cross-hole seismic surveys and rock anchor trials. Particular attention was paid to elucidating the discontinuity characteristics with reference to the presence of low shear strength planes. Rock classification techniques were used to assist in excavatibility studies and to provide guidelines for rock reinforcement selection.

Excavations were mapped in detail during construction, and supplementary rock testing was carried out. Updated interpretations were prepared, enabling the design for the temporary and permanent works to be kept under review and adjusted as work progressed.
Investigation and treatment of abandoned mine workings for underground excavations: an example from the Don Valley Intercepting Sewer scheme, Sheffield, England
Authors: Deaves A. P. , Cripps J. C.
Published: April 2008

The Don Valley Intercepting Sewer is being constructed to upgrade the sewerage system of the City of Sheffield. The principal objectives of the scheme are to alleviate flooding, reduce the frequency and amount of sewage discharges to the surface watercourses, provide adequate drainage capacity for present and projected flows and allow access to the existing sewerage system for cleaning, inspection, repair and renovation.

To achieve the operational objectives and provide favourable ground conditions for the construction of the scheme, the tunnels are driven at a low level in a sequence of Coal Measures strata which comprises the solid geological formation of the area. This sequence includes a number of coal seams, formerly of economic importance, which have been exploited by opencast and subsurface mining extraction methods from historical times to as recently as 1954.

Investigation were undertaken to establish the ground conditions in an area where a tunnel drive was to traverse a coal seam in which abandoned shallow mine workings were recorded. The data collected during the desk study and field investigations are discussed with reference to the design and construction of the tunnel works. Ground treatment was carried out by cementiteous grouting and a detailed account of the methods adopted is given.
Role of the contractor's engineering geologist in the construction of the New Studley Tunnel
Authors: Margerison R. J. , Eastaff D. J. , Norbury K. W.
Published: April 2008

The New Studley Tunnel is a replacement for part of the Elan Aqueduct, which carries water from mid-Wales to Birmingham. The 1.3 km long, 2.8 m diameter replacement tunnel was constructed through complex Carboniferous and Devonian strata affected by folding and faulting. The contractor's engineering geologist played a part in interpreting the ground conditions from the tender stage through to the completion of the works.
The Midge Hall Valley Sewer: a case history in tunnelling through Coal Measures rocks
Authors: Richardson M. , Eddleston M. , Arthur C. D. , Nguyen V. M.
Published: April 2008

Engineering geology plays an indispensable part in the planning and construction of tunnels. This is demonstrated by the construction of the Midge Hall Valley Sewer tunnel through Middle Coal Measures rocks in the vicinity of Rochdale, Greater Manchester.

A three-phased site investigation was carried out, at the planning, design and construction phases of the project. These lead to the determination of ground reference conditions, the choice of tunnelling method and the target cost of the tender.

Throughout the project good communication was maintained between the client, the engineer to the project and both the site investigation contractor and the tunnelling contractor. This invoked confidence in the prediction of ground conditions forward of the tunnel face, and in the excavation and support methods used during the works. This example demonstrates the high value of good quality engineering geological input throughout a high risk construction project such as tunnelling.
Masonry retaining wall reconstruction and rock face stabilization using soil nails, masonry and dowels
Authors: Gannon J. A.
Published: April 2008

The World Heritage Site of New Lanark Mills in Scotland is a living museum recreating the environment of a self-contained community which lived and worked in the village situated adjacent to the middle reaches of the River Clyde. The village buildings and infrastructure date from the early 19th century and owe their existence to the philanthropist Robert Owen. They are undergoing a long-term programme of restoration and repair. Much of the village is constructed of local Devonian sandstone
masonry, with timber and cast iron also much in evidence. The buildings comprise wool mills (the machinery of which was powered by water-driven turbines fed by the river), a school house, an engine house, a church and dwellings. The buildings carry listed status and all works of reconstruction proceed on the basis of replacing like for like.

Geological factors shaped the investigation, design and construction of remedial works to a rock face and retaining wall which were showing signs of instability. The technique of soil nailing is reviewed as a method of stabilizing masonry retaining walls, of which there are many hundreds of metres length on this site. The works were conceived, designed and brought to construction by geotechnical specialists aided by structural engineers.
Soil nailing in the Hastings Beds
Authors: Pedley M. J. , Pugh R. S.
Published: April 2008

At Peasmarsh in East Sussex a 70° cutting, between 6.5 and 11 m high, was made in the Hastings Beds using the soil nailing technique in conjunction with a seeded geomat to provide a green' finish. Engineering geological investigations led to the adoption of soil nailing, and the design and installation of the nails. The cut slope and selected nails were instrumented and the cutting's performance observed.
Application of a geomembrane leak location survey at a UK waste disposal facility
Authors: Mosley N. G. , Crozier F.
Published: April 2008

Electrical leak location surveys have been undertaken in the US for several years. 1993 has seen the first application of this technology on a newly constructed soil-covered HDPE geomembrane at a waste disposal site in the UK. The technology exploits the electrical insulating properties of geomembranes. A voltage placed across the geomembrane is surveyed to identify anomalies where electrical current is flowing through leaks in the liner. In its first UK application both ‘pin
hole’ leaks and larger cuts in the geomembrane were located and repaired prior to commissioning the waste disposal facility.
Engineering properties and disposal of gypsum waste
Authors: Griffin A. R.
Published: April 2008

This paper describes the investigation and design of a site for the safe disposal of solid gypsum waste derived as a by-product from the manufacture of titanium dioxide pigment. The site is on the east coast of Malaysia located on an area underlain by soft marine clays. The final design of the containment structure and final disposal scheme was dictated by the nature of the ground and the consequences of the detailed environmental assessment. The waste material has some similarities with FGD gypsum and phosphogypsum but the presence of a high iron content provides the material with additional beneficial properties for landfilling.
Evaluation of geotechnical and hydrogeological properties of wastes
Authors: Beaven R. P.
Published: April 2008

This paper uses evidence from three sources to evaluate the geotechnical and hydrogeological properties of waste. The effect of landfilling on leachate levels (through a reduction in refuse storativity) is illustrated using the results of leachate-level monitoring at two sites. The effect of landfilling on refuse permeability is shown by results from leachate pumping tests. The physical and hydrogeological properties of refuse were investigated using a large-scale compression cell. The design and operation of the compression cell are described and preliminary results from initial testing presented.
Geological and other influences on the design of containment systems in hard rock quarries
Authors: Mann D. C.
Published: April 2008

It is common practice in the UK to restore abandoned quarries by landfilling. Modern landfill facilities are designed on the principle of containment of wastes, leachate and gases, but, in hard rock quarries, there are particular problems which must be overcome. This paper describes the engineering design of the containment systems proposed for use in three hard rock quarries located in different parts of the UK. At each of the three sites the design has been influenced by the local geology and hydrogeology, and the use of indigenous materials has been a priority. The regulatory authorities have a statutory responsibility in the licensing of new landfill facilities, but are becoming increasingly involved in the early planning of these sites. Their influence on the evolution of the three designs is assessed by comparing the three containment systems.
Laboratory investigations into designated high-attenuation landfill liners
Authors: Bright M. I. , Thornton S. F. , Lerner D. N. , Tellam J. H.
Published: April 2008

The present UK landfilling policy of total containment of waste is likely to present long-term problems in terms of liner integrity, so that additional leachate control measures may become a necessity. The design of economic liners from natural materials with high-attenuation characteristics that could serve as a back-up for containment sites is discussed. Laboratory column experiments are currently underway to test the performance of proposed liner recipes using a range of widely available materials. The results obtained should indicate the extent to which it is possible to design a liner material on the basis of simple measurements.
Modelling
in situ
water uptake in a bentonite—sand barrier
Authors: Thomas H. R. , Rees S. W , Kjartanson B , Wan A. W. L , Chandler N. A.
Published: April 2008

An
in situ
experiment being carried out to investigate the hydraulic behaviour of a bentonite—sand engineered barrier is described. Hydraulic interactions between the barrier, surrounding granite and a concrete sealing plug are being measured some 240 m below ground level at AECL's Underground Research Laboratory (URL). Observations from the test to date indicate that the buffer mass is taking on moisture. Pore pressures in the near-field rock appear to be low but generally continue to change with time. In contrast, pore water pressures in the far-field rock essentially remain constant. Supporting numerical investigations are also described. An axisymmetric solution of Richards' pressure head based flow equation is used. The model was calibrated against known experimental results and subsequently used to provide the anticipated response of the
in-situ
experiment. The importance of the unsaturated hydraulic properties of the granite are revealed, leading to the conclusion that further data on these properties, when subject to high suction values, are required.
A geochemical data management system for radioactive waste repository feasibility investigations
Authors: Nathanail C. P.
Published: April 2008

The geochemistry and hydrogeochemistry of the ground is a prime influence in determining the suitability of a site for the underground storage of radioactive waste. Geochemical testing is carried out during and after drilling of investigation boreholes to determine the nature of the groundwater regime and the connectivity between the repository and the biosphere.

aim of this paper is to describe a data management system for the entry, validation and reporting of geochemical testing using dBase IV version 1.5 running under MS-DOS 5.0 on an IBMcompatible 486DX personal computer.

Data entry is in four phases for sample register details, tracer sample analyses, hydrochemical sample inventory details and hydrochemical sample analyses. Each record is committed on entry and then validated by a senior chemist. A six-stage validation scale was developed to track the progress of the analysis for individual determinands.

Results are reported in full for each sample and as a series of summary sheets for rapid assessment. The summaries display the QA status of each analysis from ‘not required’ through ‘pending’ to ‘fully documented procedures’. Output is to a laser printer and a series of Lotus 1-2-3 spreadsheet files for further analysis and interpretation. Reporting is both interim on a daily and fortnightly basis during testing and final upon completion of testing.

The conflicting requirements of security, quality assurance, ease of use and a rapidly evolving specification mean that communication between geochemists and the database programmer have to be effective and response times minimized.
Diffusion of contaminants through a clay barrier under acidic conditions
Authors: Mohamed A. M. O. , Yong R. N.
Published: April 2008

In this study, the characteristics of contaminant-soil interaction and retention regarding soil and influent pH values were examined. Leaching column tests were used to investigate the retention capacity of a natural clay soil. The laboratory tests showed good attenuation for Pb
2+
and Zn
2+
and lesser attenuation for Na
+
, K
+
, Ca
2+
and Mg
2+
salts under acidic conditions.

To calculate the diffusion parameters, a phenomenological approach was developed. The technique is based on an analytical solution via a Fourier series, a non-dimensional analysis and the measured experimental data. The calculated diffusion parameters were similar to values reported in the literature. The developed technique can be used to calculate diffusion parameters for both adsorption and desorption processes.
Waste disposal, regulatory policy and potential health threats
Authors: Yong Raymond N.
Published: April 2008

The issues with respect to development of a safe liner-barrier system for waste containment facilities in the land disposal of wastes are examined in relation to the need for minimization of potential health and environmental threats. The influence of regulatory policies or attitudes, e.g. the ‘Compliance (Mandated) Requirement’ and the ‘Performance Requirements’ attitudes, on the requirements for barrier system design and performance is seen to be very significant. Ensuring protection of public health and the environment is central to the construction and performance requirements and criteria of the barrier system. Regulatory control and measures designed to fulfil minimization of public health threats must address the basic question of ‘what constitutes a health threat’, especially since one needs to ensure proper and secure barrier performance for 250–500 years or more. The performance of substrate material and engineered landfill barriers as competent liner systems, particularly with respect to substrate control on waste leachate containment and transport, must be well understood if proper protection of public health and the environment is to be obtained.
Risk assessment: where are we, and where are we going?
Authors: Jefferies Michael , Hall David , Hinchliff John , Aiken Morag
Published: April 2008

This paper was presented as the keynote address to a subsequent session on ‘Investigation, hazard assessment and remediation of existing landfills’. As such, the paper is written as an overview to introduce risk assessment, and hopefully encourage and convince engineering geologists to adopt the techniques.

The paper outlines how modern risk-based management techniques are applied within the engineering geology of waste storage and disposal. Both current usage (‘where are we?’) and future developments (‘where are we going?’) are discussed. References and a discussion of useful software is provided to assist those starting out.
Imaging groundwater ‘steps’ in push moraines by georadar
Authors: Van Overmeeren R. A.
Published: April 2008

Georadar has proved to be a valuable new geophysical technique for non-destructive groundwater exploration in the Netherlands, yielding detailed continuous images to depths of 40 m under favourable conditions. During the Saalian, glacial action in the Netherlands deformed the fluvial deposits and created ice-pushed ridges or push moraines. Most of these displaced fluvial sediments are coarse-grained sands and gravels, but thin clay layers which acted as sliding planes during the glacial deformation are also present. The ice-pushed ridges are infiltration areas and the thick coarse sediments are important aquifers of the Netherlands. To be able to adequately manage these groundwater resources and forecast their depletion and contamination, the groundwater flow must be modelled in detail. Steeply dipping clay layers impede groundwater flow and create ‘steps’ in groundwater levels. Georadar surveying enables water tables to be imaged precisely and detects the exact location of such groundwater steps and vertical barriers.

During a georadar survey near the village of Epe on one of the major ice-pushed ridges of the Netherlands, a sudden and spectacular offset in the water-table reflector was observed. The jump in the reflector could be traced along a number of parallel lines. A series of nine boreholes drilled to verify the georadar results confirmed the presence of important steps in the water table and proved the georadar predictions on depths and offsets to be remarkably close to reality.
The use of Rayleigh waves to detect the depth of a shallow landfill
Authors: Butcher A. P. , Tam W. S. A.
Published: April 2008

This paper describes a case study to determine the extent of shallow landfill on a site that was to be traversed by a new road. Pre-contract estimation of the quantities of landfill to be removed were required and, though the approximate lateral extent of the landfill was known, the depth was not. An opportunity therefore presented itself whereby measurements of the depth of landfill could be made using a non-intrusive geophysical technique and the subsequent excavation would allow the physical measurement of the actual depth of the landfill.

The determination of the depth of shallow landfill using non-intrusive methods is difficult. Conventional surface geophysics needs high stiffness contrasts, consistent strata depths along the survey lines and experienced interpretation to achieve the best results. The Rayleigh wave technique offers the potential to obtain wave velocity against depth profiles at discrete points across a site so better enabling a section to be built up to show the extent of the landfill.

The paper outlines the Rayleigh wave technique, presents the data and compares the predicted sections with those produced from the site surveying data. The case study illustrates the cost effectiveness of good quality Rayleigh wave measurements with straightforward site specific interpretation to quantify the extent of shallow landfill.