bluuebunny/crossref_metadata_2025_split huggingface dataset:
Coastal erosion and slope instability at Downderry, south-east Cornwall: an outline of the problem and its implications for planning
Authors: Coard M. A. , Sims P. C. , Ternan J. L. 
Published: April 2008

Abstract
The Quaternary head deposits which overlay a wave-cut shore platform along a 2 km sector of coast between Seaton and Downderry in south-east Cornwall, have been subjected to significant coastal erosion over many years. As a result, a number of landslips have occurred with considerable damage and even loss of cliff top dwellings. An outline of recent investigations conducted on the cliff and landslip sections with regard to slope stability and the nature of the head deposits is presented. Attention is drawn to the need for adequate drainage of the cliff material, particularly in the siting of gutter soakaways from the cliff top settlements.
Despite the history of landslipping in this coastal sector, planning permissions have been granted and a number of new dwellings have been constructed on the cliffs. Ultimately, these properties will be affected by the receding cliff edge and associated slope failures.
The paper thus reviews the efficacy of both public and private coastal defence schemes, particularly in relation to the overall stability of the head materials, beach sediment budgets and the ‘natural’ protection provided by longshore sediment transport at the foot of the cliffs.
An overview of site investigation and long-term tunnelling-induced settlement in soil
Authors: Attewell P.B. 
Published: April 2008

Abstract
Ground settlement amplitudes and distributions in clay soils depend both on ground losses at the tunnel and on longer-term consolidation effects. In granular soils there is a dependency on an initial density state. The problem of the degree of ground movement transfer into structures, building foundations and buried pipelines, can be examined both analytically (Winkler-style modelling) and numerically (finite element modelling). Finally, it is noted that published damage criteria for buildings are not accurately applicable to tunnelling-induced damage.
Induced subsurface movements associated with the presence of natural and artificial underground openings in areas underlain by Cretaceous Chalk
Authors: Edmonds C. N. 
Published: April 2008

Abstract
Induced subsurface ground movements in areas of pre-existing metastable ground conditions associated with natural solution features and underground mining in the Chalk, commonly produce dolines (sinkholes) and crown holes (subsidence pits) at the surface, respectively. Although the nature of underground movements differs between natural and artificial sources, the range of subsidence triggers is generally the same. Man’s Activities via urban development can increase the incidence of subsidence, and, therefore, subsurface movements too. Considerable damage to buildings, and even loss of life, can result from induced subsurface movements. New hazard mapping techniques are available to predict zones where the subsidence hazard due to these movements is greatest, hence ground investigations, foundations and drainage measures can be purpose-designed to take account of possible ground movements. This approach greatly improves the engineering geological understanding of ground movements at chalkland sites and gives confidence that the most critical zones of ground have been both accurately delineated and correctly assessed.
A study of the effects of mining relatively shallow overlying longwall panels with staggered inter-panel pillars at Sigma Colliery, South Africa
Authors: van der Merwe J. N. 
Published: April 2008

Abstract
When two coal seams in close proximity are to be mined by longwall, a number of alternatives regarding the placing of the panels relevant to one another are possible. The main factors influencing the final choice are gate road stability, face conditions and the extent of surface deformation.
The paper describes the rationale and investigations leading up to the decision to stagger overlying longwall panels at Sigma Colliery. A two dimensional boundary element program was used to predict the stability of gate roads, after having obtained excellent correlation between predicted and actual conditions in a test case. Observations to date also confirm the prediction of stability conditions in the staggered panel’s.
Surface deformations were measured in detail. A computer program was written which permitted the analysis of a huge volume of data in a very short time. The results of the analysis confirm that less damaging surface disturbance is caused by staggering the panels, compared with superimposing them.
Subsidence prediction by the use of influence functions
Authors: Bell F. G. , Coulthard J. M. 
Published: April 2008

Abstract
Surface subsidence occurs as a result of extraction of a mineral resource at some depth below the surface. Most coal is mined in this way in the United Kingdom and such coal workings are responsible for the great majority of subsidence and associated damage that occurs. Hence it has become necessary to develop methods of predicting the amount of subsidence likely to develop due to coal mining.
Many methods have been advanced, dating back to the latter part of the last century. However, they can be separated into three groups, namely, the theoretical, the empirical and the semi-empirical methods. A number of these methods were reviewed with the object of selecting one which lent itself to the development of a relatively simple computer program that could be used on a microcomputer.
The complementary influence function method was chosen and, although by no means a perfect method, a program was developed to predict a complete subsidence profile for a given set of circumstances. The concept of complementary influence functions considers not only the influence of the extracted elements on a surface point but also the influence of the material remaining after extraction. The subsidence of a surface point then is found by integrating the response of every element in the area of influence, whether mined or not. The mined region is divided into a number of mined and unmined elements. Summing the influence of all the elements on a particular point yields a picture of subsidence at that point. If this is done for a number of points across the proposed extraction area, then a complete picture of the subsidence over the area can be obtained.
The geology of Castlefields Mine, Dudley, and its effect on the stability of the mine roof
Authors: Forster A. 
Published: April 2008

Abstract
The mining of the Wenlock Limestone, which has taken place in the West Midlands during the last two hundred years, has resulted in a long and continuing history of subsidence and crownhole formation in a mainly urban area.
In 1983, as part of a major study of the abandoned limestone mines, a programme of micro-seismic emission monitoring of rock falls and of rock paste infilling trials was started at the Castlefields Mine near Dudley.
The mine is in Upper Wenlock Limestone with an overburden of approximately 22 m comprising about 1.5 m Passage Beds overlain by Lower Ludlow Shale. A number of stages of instability were observed, ranging from initial slabbing failure of the Passage Beds to extensive upward void migration through the Lower Ludlow Shale to within a few metres of the surface.
The pattern of joints, and their condition, plays an important role in controlling the instabilities in a mine. Five joint sets, with varying degrees of dilation, movement and infilling, were identified in a survey of structural discontinuities in Castlefields Mine. One master joint set, characterized by uneven dilation and clay infilling, was found to exert a major influence on the position and development of roof instabilities within the mine.
In this paper, the lithology, geological and mining history and structure of Castlefields Mine are described and their influence on mine stability discussed.
A case study on past shortwall mining methods and the risk of ground subsidence in the Lanarkshire Coalfield, Scotland
Authors: Evans J. A. , Lawrence M. S. 
Published: April 2008

Abstract
A site investigation involving archival research and a borehole drilling programme was carried out in order to assess the risk to surface stability from abandoned shallow shortwall mineworkings at a proposed housing development site located on the Lanarkshire Coalfield.
Of the exploitable coal seams present below the site, the Ell coals were confirmed to be at shallow depth and were mined into the mid-1950’s from the adjacent Thankerton Colliery. The Ell coal in this part of the coalfield occurs in three distinct leaves, the uppermost of which crops through the site and was not mined. The investigation confirmed the extent of mining in the Mid and Lower Ell seams which were proved to be no more than 0.5 m apart with a combined unworked thickness of 1.5 to 1.9 m.
The mine records indicate that the Mid and Lower Ell seams were mined by shortwall methods, individual panels having been worked from a network of main roadways or headings with subsidiary side or haulage roadways. Due to the thin partings between the seams, a method of mining each seam from common roadways extending to the full height of combined seams was used in addition to single seam workings of the thicker Mid Ell. From the abandonment information it has been deduced that mining involved the total extraction of the Mid Ell whilst maintaining the integrity of the roadways. Subsequently, the same roadways allowed access to the Lower Ell for extraction below the collapsed Mid Ell workings.
The investigations recorded the shortwall panels to be largely consolidated but also noted that several panels had been undeveloped with respect to the lower seam and that some roadways were confined to the Mid Ell seam. The borehole investigation together with the use of down-the-hole closed circuit television (CCTV) also confirmed the presence of broken ground and open voids of 0.3 to 2.0 m height along former roadway alignments.
A risk to surface stability was identified from these open voids and development constraints zones are discussed in relation to the likely mining methods. Seam depths, void heights, condition of roof strata and thickness of superficial cover are considered in the assessment of void migration mechanisms arising from such a past mining situation.
Consolidation characteristics of clays from self-boring pressuremeter tests
Authors: Clarke B. G. 
Published: April 2008

Abstract

The self-boring pressuremeter can be used to determine in situ consolidation characteristics of clays (Clarke
et al.
1979). The test procedure includes undrained loading from which total horizontal stress, shear modulus and strength can be determined. Excess pore pressures are generated during loading. These decay during the holding portion of the test when the membrane is held at about 10% cavity strain. The rate of decay is used together with a theoretical prediction of consolidation around a cavity to determine the horizontal coefficient of consolidation. The main disadvantage of this is the difficulty with measuring the pore water pressure. As the excess pore pressures dissipate the total applied pressure within the membrane is reduced. The total pressure can be monitored more accurately than the pore pressure and, hence, holding tests based on total pressure decay would be a preferred field technique. This paper discusses work carried out at the SERC Bothkennar soft clay site where undrained SBP and holding tests were carried out down to a depth of 19.6 m. The tests have been interpreted using total pressure observations. The tests have also been interpreted using a finite element package which includes the Cam Clay model and coupled consolidation. This interpretation allows a comparison to be made between the use of pore and total pressure decay in the analysis and recommendations for an alternative test procedure are made.
Self-boring pressuremeter testing in London Clay
Authors: O’Brien A. S. , Newman R. L. 
Published: April 2008

Abstract
With the large amount of literature on London Clay, it is generally assumed that its properties are both well understood and well documented. However, there are few reports of how man-made features, such as tunnels, can alter the in situ horizontal stress field and stiffness of London Clay. This paper describes the self-boring pressuremeter tests carried out at a site in north east London at locations in close proximity and remote from a London Underground Ltd tunnel. Two aspects are considered; firstly, the analysis, assessment and interpretation of data and, secondly, the effect of the tunnel on the profiles of in situ horizontal total stress and coefficient of earth pressure at rest.
The analysis of the test data has indicated that interaction between the instrument and the soil may effect the measured ‘lift off’ pressure. Methods of interpretating the test data are suggested. The variation with depth of the ratio of shear modulus (at a particular cavity strain) to mean effective stress proved to be a useful method of checking the reliability of the test data.
During the pressuremeter tests unload-reload loops were performed to measure shear modulus. Because of the nonlinear stress-strain behaviour of London Clay it is recommended that the magnitude of cavity strain imposed during the unload-reload loop is taken into account during the assessment of shear modulus. Finally, in situ stress and stiffness from the self-boring pressuremeter tests are compared with case history data.
Self-boring pressuremeter in situ lateral stress assessment in London Clay
Authors: Corke D. J. 
Published: April 2008

Abstract
Recently a considerable amount of self-boring pressuremeter testing has been carried out in London Clay. This paper considers the results of tests from four sites and the methods for obtaining the in situ total lateral stress, undrained shear strength, limit pressure and shear modulus are reviewed.

In order to provide some means of checking the consistency of results produced from self boring pressuremeter tests, the normalized parameters
C
u
/
P
I
(shear strength/limit pressure) and
P
0
/
P
1
(in situ total lateral stress/limit pressure) have been assessed and found to be reasonably consistent with depth within the London Clay for a wide range of shear strengths.

On all of the sites considered, the measured lateral pressures were generally higher than would have been assumed from published information. During the course of the erosion of what is generally considered to have been several hundred metres of material, it is possible that passive conditions could have existed and may have had a controlling influence on in situ lateral pressures both in the past and at present. The self-boring pressuremeter tests generally indicate that plastic deformation of the soil commences at pressures only slightly higher than the measured in situ lateral stress. Also, the values of passive pressure calculated using the pressuremeter are similar in value to those stresses. It is concluded that at some locations London Clay may be at, or near to, the passive condition.
It is recommended that long-term monitoring of ground pressures on deep structures is undertaken to provide independent confirmation of the findings of this paper. Also, a field study of the effects that self-boring can have on the ground, particularly in very stiff and hard clays is needed. This would clarify the influence these effects may have on the test results.
Some recent in situ stress testing experience with strong clays and weak rocks in Britain
Authors: Stevenson M. C. , Martin J. H. , Squire P. O. 
Published: April 2008

Abstract

Intensive pressuremeter testing at two sites in lower Lias clays, together with laboratory testing has enabled general conclusions to be drawn about strength-stress compatibility in heavily overconsolidated materials. Three limit states of effective horizontal stress are described which demarcate in situ test results into four distinct ranges relating to the stress history of the material. These may be used to validate pressuremeter measurements. The
in situ
test results for the two sites are related to the regional geomorphology and the results of conventional geological logging.
The interpretation of standard penetration tests in geologically aged sands
Authors: Barton M. E. 
Published: April 2008

Abstract
The standard penetration test represents a traditional and convenient method for the assessment of the engineering properties of cohesionless soils for the purpose of foundation design. This test, however, is not a direct measure of the static load/displacement characteristics of a sand and hence it is an empirical one in which the blow count is correlated firstly with the in situ density and shear strength obtained by other methods and, secondly, with case records of foundation performance. Most, if not all, of the existing correlation charts are based either on measurements of density and shear strength in remoulded sands or on the performance of fills or recent sands. The unique properties of sands which have geologically aged (that is been subjected to a variety of diagenetic processes) are often ignored with the erroneous assumption that the correlation charts will apply equally to all sands.
The paper examines the penetration resistance of uncemented sands in Southern Britain ranging in age back to the Jurassic. It is seen that there is a marked difference between tests carried out well above the groundwater table (dry tests) and those either below or in close proximity to it (wet or saturated tests). Only dry tests give the high resistances expected from the very dense and strong geologically aged sands. These results show an exponential increase in blow count versus depth and vertical effective pressure. Reasons for the reduced resistances measured in water filled boreholes are discussed. Of significant influence is the markedly moisture sensitive strength behaviour of ancient sands. In addition, the conditions of the test are such that other adverse effects, inevitable with conventional boring operations, can be operative and hence weaker foundation characteristics may be assumed than is actually the case in the undisturbed sand.
Applications of continuous dynamic probing in ground investigation
Authors: Card G. B. , Roche D. P. , Herbert S. M. 
Published: April 2008

Abstract
Four case histories are described where the continuous dynamic probing technique has been applied in chalk and non-cohesive deposits. The results are correlated with adjacent conventional boreholes for which standard penetration test (SPT) data have been obtained. The applications of this technique are discussed and reviewed, and consideration is given to the degrees of consistency and inconsistency in the results obtained, particularly the correlation with SPT.
Use of a dynamic penetrometer as a ground investigation and design tool in Hertfordshire
Authors: Huntley S. L. 
Published: April 2008

Abstract
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

Abstract

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

Abstract

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

Abstract
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.