bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relationship between electrical resistivity and basic geotechnical parameters for marine clays
Authors: Long Michael , Donohue Shane , L’Heureux Jean-Sebastien , Solberg Inger-Lise , Rønning Jan Steinar , Limacher Romaric , O’Connor Peter , Sauvin Guillaume , Rømoen Magnus , Lecomte Isabelle 
Published: October 2012

Recently, considerable efforts have been made in the attempt to map quick clay areas using electrical resistivity measurements. However there is a lack of understanding regarding which soil parameters control the measured resistivity values. To address this issue, inverted resistivity values from 15 marine clay sites in Norway have been compared with basic geotechnical index properties. It was found that the resistivity value is strongly controlled by the salt content of the pore fluid. Resistivity decreases rapidly with increasing salt content. There is also a relatively clear trend of decreasing resistivity with increasing clay content and plasticity index. Resistivity values become very low (≈5 Ω·m) for high clay content (>50%), medium- to high-plasticity (Ip ≈ 20%) materials with salt content values greater than about 8 g/L (or corresponding remoulded shear strength values greater than 4 kPa). For the range of values studied, there is poor correlation between resistivity and bulk density and between resistivity and water content. The data studied suggest that the range of resistivity values corresponding to quick clay is 10 to 100 Ω·m, which is consistent with other published limits. A comparison is made between two-dimensional electrical resistivity tomography (ERT) and resistivity cone penetration test (RCPTU) data for two of the sites and the two sets of data show similar trends and values irrespective of scale effect.
Optimum use of material: selection of limits for suitable earthworks fill: Irish experience
Authors: Rutty P. C. , Johnston T. P. 
Published: October 2012

Abstract
Most Irish earthworks fills consist of glacially derived soils with some excavated rock. Excavated rock and granular glacial soils will nearly always provide acceptable fill. Cohesive glacial soils are generally well-graded tills, characterized by low plasticity and relatively high undrained strength. These cohesive tills provide acceptable fills providing they can be placed and compacted to provide sufficient strength and stiffness, and achieve low air voids.
In standard earthworks specifications, acceptability limits for cohesive fills may be specified by moisture content, moisture condition value or undrained shear strength. The lower limit of strength or moisture content adopted ensures acceptable trafficability, compressibility and stability. Laboratory relationship testing is carried out to establish the relationship between the various test properties.
Experience has shown that simple measurements and descriptions of strength derived from data collected routinely during ground investigations are adequate for estimation at tender. For construction control, moisture condition value testing has been widely adopted, is suitable for the range of soils encountered and provides quick results allowing timely decision-making. Irish tills are moisture susceptible and on-site results allow marginal materials to be processed on site for re-use, providing care is taken to work only in dry weather and protect placed fill.
Use of tyre bales as lightweight fill for the A421 improvements scheme near Bedford, UK
Authors: Hodgson Ivan F. , Beales Stephen P. , Curd Martin J. 
Published: October 2012

Abstract
The A421 improvements scheme near Bedford in England requires construction of the new dual carriageway and a realigned side road over two former borrow pits that have been partially infilled with up to 20 m of soft clay. The side road was constructed using lightweight fill comprising ‘Maxit’ expanded clay aggregate and tyre bales manufactured from old vehicle tyres under a Standard that produces an engineering material from a former waste product.
A deskstop study and a series of ground investigations were carried out to establish the history of the site and the current condition of the infill and to provide parameters for geotechnical design. The solution was chosen after consideration of various options against a number of constraints. The bulk of the embankment was formed from layers of tyre bales with alternate thin levelling layers of ‘Maxit’. A period of surcharge with wick drains was incorporated to reduce settlements in the long term and a temporary toe berm provided for stability during construction. The use of tyre bales on this project provided a number of environmental benefits as well as practical benefits including cost and ease of storage, handling and placing.
Use of industrial by-products in earthworks in the Czech Republic
Authors: Krest František 
Published: October 2012

Abstract
The use of industrial by-products as a construction fill is set to increase in order to minimize the environmental impact of large infrastructure construction schemes. The Czech Republic is one of a number of countries where these products are now used. This paper gives a brief background to the use of colliery spoil, fly ash, blast furnace slag and PRESTAB, with particular reference to the construction of the D47 motorway and R48 expressway near Ostrava.
The use of deep counterfort drains as an effective method of stabilizing cuttings constructed in overconsolidated clays
Authors: Macdonald G. J. , Vooght A. R. , Parkin S. 
Published: October 2012

Abstract
Slope failures in cuttings constructed in heavily overconsolidated clays often occur after a period of 20 to 30 years due to the gradual dissipation of negative pore pressures and the effects of water ingress into the slopes. These slope failures are often stabilized with the installation of deep counterfort drains, which reduce the pore water pressures on the potential critical slip planes and act as a reinforcing element in the slope. Counterfort drains are normally designed using empirical methods. However there is little published data on drain performance. This paper summarizes the findings of a research project undertaken by Mouchel on behalf of the Highways Agency to assess the performance of counterfort drains installed in two highway cutting slopes that have been monitored over a number of years. The study has shown that measured pore water pressures can exceed the theoretical pressures, due mainly to what is believed to be the poor performance of the counterfort drains and that the apparent improved slope stability may be primarily due to the reinforcing effect of the drains within the slope. Further studies are required to determine the effects of construction techniques and materials used on the performance of counterfort drains before the efficiency of the existing empirical design methods can be fully assessed.
The use of soil moisture deficit as a trigger mechanism for targeted monitoring of earthworks slopes
Authors: Macdonald G. J. , Vooght A. R. , Parkin S. 
Published: October 2012

Abstract
Seasonal effective stress changes can result in progressive failure of clay embankments. These seasonal effective stress changes are reflected in the soil moisture deficit (SMD) values. This paper explores the relationship between slope failures and SMD for both embankment and cuttings and proposes an SMD trigger level at which more cost effective targeted monitoring of earthwork slopes, considered to be at risk of failure, should be undertaken. The paper presents a methodology for obtaining and reviewing SMD data and discusses the use of rainfall and temperature forecasts as a predictor of future short-term rapid changes in SMD.
Investigating the impacts of climate change on slopes: field measurements
Authors: Toll D. G. , Mendes J. , Gallipoli D. , Glendinning S. , Hughes P. N. 
Published: October 2012

Abstract
Climate change has the potential to have significant effects on the stability and serviceability of earthworks slopes, impacting on the performance of transport infrastructures. This paper describes how a unique facility for engineering and biological research was established in NE England through the BIONICS Project (Biological and Engineering Impacts of Climate Change on Slopes). It describes the building and monitoring of a full-scale embankment representative of road/rail embankments in the UK. The paper presents the results of monitoring of pore water pressure carried out between 2007 and 2009. The pore water pressures within the upper 3 m of the embankment have been largely positive, in some case approaching hydrostatic conditions after wetter periods. This is largely due to the wet nature of the summers in both 2007 and 2008 since monitoring began, as well as the application of artificial inundation using a climate control system. Negative pore water pressures (suctions) of the order of −30 kPa were recorded at greater depths below 3 m. The experimental facility provides essential field measurements that can be used to calibrate numerical models of soil responses to climatic changes and gain a better understanding of the response of engineered UK fills to climate events.
Revision of BS 6031: Code of practice for earthworks
Authors: Lamont Donald 
Published: October 2012

Abstract
The paper summarizes the work of BSI committee B/526/0-/0-/DG1 which is responsible for the current revision of BS 6031:1981 ‘Code of Practice for Earthworks’.

Explanatory note
: This paper was prepared in advance of the Earthworks Seminar whilst BS 6031 was in the process of public consultation and final revision prior to it being published in December 2009.
Stability of earthworks to Eurocode 7
Authors: Harris A. J. , Bond A. J. 
Published: October 2012

Abstract
The introduction of Eurocodes to engineering practice represents an importantchange in the approach to geotechnical engineering, as for the first time there is a unified set of codes dealing with the main structural materials including the ground. All of the Eurocodes adopt a limit state design philosophy which is different from the lumped factor of safety approach adopted by traditional geotechnical design practice. This paper examines the implications of the introduction of the Eurocodes, in particular EN1997, when assessing the stability of earthworks. It outlines the various committees responsible for the development of the codes and discusses the application of EN1997 to the assessment of the stability of slopes highlighting the difficulties in applying the various design approaches. Examples from practice are used to highlight where the code is different from traditional practice. A survey of practice in other European countries is outlined which indicates the differing approaches to ensuring adequate reliability being taken across Europe highlighting options that could be considered by the geotechnical community. The paper concludes that the introduction of the Eurocodes does not require a significant change to the way stability analysis is carried out.
Geotechnical risk and performance: with a focus on earthworks compaction and data management
Authors: Perry John 
Published: October 2012

Abstract
This paper discusses the various influences controlling risk and performance from new build to the in-service aspects of the transport infrastructure geotechnical asset of which earthworks are the major part. First it focuses on the risks associated with earthworks during construction. Compaction specifications, their origins and past supporting research results are described as are the advantages and disadvantages of the end-product. The method specification gives an insight into the development of earthworks design, construction and contracts. Recommendations are given based on modern practice and current contractual arrangements. Monitoring performance is critical to the management of geotechnical assets and the establishment of IT based methods in the UK is discussed to complete a ‘cradle to grave’ review of risk and performance aspects of earthworks.
Geotechnical asset management for the UK Highways Agency
Authors: Power C. M. , Patterson D. A. , Rudrum D. M. , Wright D. J. 
Published: October 2012

Abstract
This paper outlines the Geotechnical Asset Management Strategy of the Highways Agency (HA). The strategy operates in a series of key stages, from setting standards and advice, through data collection and analysis through to the ultimate aim of providing and maintaining an asset that meets the service level that it is required to attain. These key stages are outlined, and illustrated with examples where appropriate. The HA, and its managing agents, have progressed a significant way along the ‘roadmap’, but further work is still ongoing. A key tool for the delivery of the HA Geotechnical Asset Management Strategy is the Geotechnical Data Management System (HA GDMS). This is discussed throughout the paper, and examples of the functionality of the system are given.
Czech standards and specification for earthworks
Authors: Herle Vítězslav 
Published: October 2012

Abstract

General requirements for earthworks in the Czech Republic are given in the national standard
CSN 73 3050
‘
Earthworks
’ which has been in place since 1987. It provides information on excavation including the rather controversial seven excavatability classes, recommendation for slope and shoring of excavation, requirements for fill construction, control of compaction and tolerances of finished surfaces.

CSN 73 6133
‘
Design and execution of earth structures on roads
’ is currently being revised. Beside classical soil and rock fills it gives recommendations for the use of difficult or marginal materials such as uniform (wind drifted) sand, loess, colliery spoil, fly ash, slag.

Control of earthworks is described in
CSN 72 1006
‘
Compaction control of soils and other fills
’ which is valid for both highway and railway infrastructure as well as for buildings, landfills etc.

Apart from national standards, the Ministry of Transport supports publications of technical specifications for design (TP) and construction control (TKP) focused on certain material or technology used in highway and railway infrastructure. TP coversfor example soil improvement, soil reinforcement, use of fly ash, colliery spoil or lightweight fill. TKP givesfor example detailed requirements for the site quality control of earthworks, reinforced fill, soil nailed slopes and gabions.
The work of ISSMGE TC3 (Geotechnics of pavements) and how it links to earthworks
Authors: Correia A. Gomes , Quibel A. , Winter M. G. 
Published: October 2012

Abstract

The main goal of Technical Committee TC3 ‘
Geotechnics of Pavements
’ of the International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE) is to promote co-operation and exchange of information and knowledge about the geotechnical aspects in design, construction, maintenance and monitoring of pavements in transportation infrastructure (roads, railways, airports). Some of these aspects cover: earth structures in pavement and railway construction, compiling and homogenizing earthwork specifications, standardization of the continuous compaction control and promotion of the use of non-traditional by-products and recycled materials. This paper covers these main aspects and highlights the use of non-traditional materials in transportation earthworks.
Effects of Hemodynamics on Global and Regional Lung Perfusion
Authors: Cao Jie J. , Wang Yi , McLaughlin Jeannette , Rhee Peter , Passick Michael , Ngai Nora , Cheng Joshua , Gulotta Ronald J. , Berke Andrew D. , Petrossian George A. , Reichek Nathaniel 
Published: October 2012

Background—
Cardiac hemodynamics affect pulmonary vascular pressure and flow, but little is known of the effects of hemodynamics on lung perfusion at the tissue level. We sought to investigate the relationship between hemodynamic abnormalities in patients with left heart failure and global and regional lung perfusion using lung perfusion quantification by magnetic resonance imaging.

Methods and Results—

Lung perfusion was quantified in 10 normal subjects and 28 patients undergoing clinically indicated left and right heart catheterization and same day research cardiac magnetic resonance imaging. A total of 228 lung slices were evaluated. Global lung perfusion, determined as the average of 6 coronal lung slices through the anterior, mid, and posterior left and right lungs, was significantly lower in patients with reduced cardiac index (<2.5 L/min per m
2
): 94±30 mL/100 mL per minute versus 132±40 mL/100 mL per minute in those with preserved cardiac index (≥2.5 L/min per m
2
;
P
=0.003). The gravitational anterior to posterior perfusion gradient was inversely associated with left ventricular end-diastolic pressure (
r
=−0.728;
P
<0.001), resulting in a blunted perfusion gradient in patients with elevated left ventricular end-diastolic pressure, a finding largely attributed to the perfusion reduction in posterior lung regions. In a multivariate regression analysis adjusting for all hemodynamic variables, altered lung perfusion gradient was most closely associated with increased mean pulmonary arterial pressure (
P
=0.016).

Conclusions—
Increased left ventricular filling pressure and the resultant increase in pulmonary arterial pressure are associated with disruption of the normal gravitational lung perfusion gradient. Our findings underscore the complexity of heart-lung interaction in determining pulmonary hemodynamics in left heart failure.
Regional Changes in Wind Energy Potential over Europe Using Regional Climate Model Ensemble Projections
Authors: Hueging Hanna , Haas Rabea , Born Kai , Jacob Daniela , Pinto Joaquim G. 
Published: October 2012

AbstractThe impact of climate change on wind power generation potentials over Europe is investigated by considering ensemble projections from two regional climate models (RCMs) driven by a global climate model (GCM). Wind energy density and its interannual variability are estimated based on hourly near-surface wind speeds. Additionally, the possible impact of climatic changes on the energy output of a sample 2.5-MW turbine is discussed. GCM-driven RCM simulations capture the behavior and variability of current wind energy indices, even though some differences exist when compared with reanalysis-driven RCM simulations. Toward the end of the twenty-first century, projections show significant changes of energy density on annual average across Europe that are substantially stronger in seasonal terms. The emergence time of these changes varies from region to region and season to season, but some long-term trends are already statistically significant in the middle of the twenty-first century. Over northern and central Europe, the wind energy potential is projected to increase, particularly in winter and autumn. In contrast, energy potential over southern Europe may experience a decrease in all seasons except for the Aegean Sea. Changes for wind energy output follow the same patterns but are of smaller magnitude. The GCM/RCM model chains project a significant intensification of both interannual and intra-annual variability of energy density over parts of western and central Europe, thus imposing new challenges to a reliable pan-European energy supply in future decades.
Weakened Interannual Variability in the Tropical Pacific Ocean since 2000
Authors: Hu Zeng-Zhen , Kumar Arun , Ren Hong-Li , Wang Hui , L’Heureux Michelle , Jin Fei-Fei 
Published: October 2012

Abstract
An interdecadal shift in the variability and mean state of the tropical Pacific Ocean is investigated within the context of changes in El Niño–Southern Oscillation (ENSO). Compared with 1979–99, the interannual variability in the tropical Pacific was significantly weaker in 2000–11, and this shift can be seen by coherent changes in both the tropical atmosphere and ocean. For example, the equatorial thermocline tilt became steeper during 2000–11, which was consistent with positive (negative) sea surface temperature anomalies, increased (decreased) precipitation, and enhanced (suppressed) convection in the western (central and eastern) tropical Pacific, which reflected an intensification of the Walker circulation.
The combination of a steeper thermocline slope with stronger surface trade winds is proposed to have hampered the eastward migration of the warm water along the equatorial Pacific. As a consequence, the variability of the warm water volume was reduced and thus ENSO amplitude also decreased. Sensitivity experiments with the Zebiak–Cane model confirm the link between thermocline slope, wind stress, and the amplitude of ENSO.
Comparison of TRMM 2A25 Products, Version 6 and Version 7, with NOAA/NSSL Ground Radar–Based National Mosaic QPE
Authors: Kirstetter Pierre-Emmanuel , Hong Y. , Gourley J. J. , Schwaller M. , Petersen W. , Zhang J. 
Published: October 2012

AbstractCharacterization of the error associated with satellite rainfall estimates is a necessary component of deterministic and probabilistic frameworks involving spaceborne passive and active microwave measurements for applications ranging from water budget studies to forecasting natural hazards related to extreme rainfall events. The authors focus here on the relative error structure of Tropical Rainfall Measurement Mission (TRMM) precipitation radar (PR) quantitative precipitation estimation (QPE) at the ground by comparison of 2A25 products with reference values derived from NOAA/NSSL’s ground radar–based National Mosaic and QPE system (NMQ/Q2). The primary contribution of this study is to compare the new 2A25, version 7 (V7), products that were recently released as a replacement of version 6 (V6). Moreover, the authors supply uncertainty estimates of the rainfall products so that they may be used in a quantitative manner for applications like hydrologic modeling. This new version is considered superior over land areas and will likely be the final version for TRMM PR rainfall estimates. Several aspects of the two versions are compared and quantified, including rainfall rate distributions, systematic biases, and random errors. All analyses indicate that V7 is in closer agreement with the reference rainfall compared to V6.
Convective Bursts, Downdraft Cooling, and Boundary Layer Recovery in a Sheared Tropical Storm
Authors: Molinari John , Frank Jaclyn , Vollaro David 
Published: October 2012

Abstract
Tropical Storm Edouard (2002) experienced episodic outbreaks of convection downshear within the storm core in the presence of 11–15 m s−1 of ambient vertical wind shear. These outbreaks lasted 2–6 h and were followed by long periods with no deep convection. Flights from U.S. Air Force reconnaissance aircraft within the boundary layer were used to investigate the cause of one such oscillation. Low equivalent potential temperature θe air filled the boundary layer as convection ceased, creating a 4–6-K deficit in θe within the convective region. Soundings within 110 km of the center were supportive of convective downdrafts, with midlevel relative humidity below 15% and large downdraft CAPE. Deep convection ceased within 75 km of the center for more than 8 h. Tangential velocity reached hurricane force locally during the convective outbreak, then became nearly symmetric after convection stopped, arguably as a result of axisymmetrization, and the storm weakened. Nevertheless, the corresponding lack of convective downdrafts during this period allowed surface heat and moisture fluxes to produce substantial increases in boundary layer entropy. A new burst of convection followed. Consistent with recent papers it is argued that tropical cyclone intensification and decay can be understood as a competition between surface heat and moisture fluxes (“fuel”) and low-entropy downdrafts into the boundary layer (“antifuel”).