bluuebunny/crossref_metadata_2025 huggingface dataset:
Fracture mechanics in ground improvement design
Authors: Schnaid F. , Spinelli L. de F. , Iturrioz I. , Rocha M. M.
Published: November 2009

This paper discusses the mechanical response of shallow footings on a double-layer system where the upper layer is artificially cemented. The study combines measurements from small-scale laboratory models and results from numerical analysis based on a discrete element method. Both experimental and numerical evidence identifies the propagation of fractures within the cemented layer as having a dominant effect that controls the load-settlement response of the footing. A discrete method of fracture propagation was applied to soil mechanics and proved to be capable of capturing essential features of the failure mechanism developed under the footing. Data from various thicknesses, degrees of cementation and compaction energies of the cemented layer are reported, the combined analysis of which yields detailed and pertinent information on the design of strip footings on a double-layer system.

Cet exposé examine la réponse mécanique d'assises peu profondes sur un systéme à double couche où la couche supérieure est cimentée artificiellement. L'étude combine des mesures prises sur des modéles de laboratoire à petiteé chelle et les résultats d'analyses numériques basées sur une meéthode d'éléments discrets. Les preuves expérimentales et numériques montrent que la propagation de fractures au sein de la couche cimentée a un effet dominant qui gouverne la réponse charge-affaissement de l'assise. Une méthode discréte de propagation de fracture aété appliquée aux mécaniques du sol et s'est révelée capable de saisir les caractéristiques essentielles du mécanisme de défaillance développé sous l'assise. Nous rapportons les donneées avec diversesé paisseurs, divers degrés de cimentation et diversesé nergies de compaction, données dont l'analyse combinée produit une information pertinente et détaillée sur la construction des assises en bandes sur un systéme à double couche.
Model studies of embedded circular footing on geogrid-reinforced sand beds
Authors: Sitharam T. G. , Sireesh S.
Published: November 2009

This paper describes laboratory model tests to determine the bearing capacity of an embedded circular footing supported by multiple layers of geogrid-reinforced sand beds. The embedment depth ratio of the footing was varied from zero to 0·6. The tests were conducted with one variety of geogrid in sand compacted to 70% relative density. Besides load settlement data, deformations on fill surface, strain in geogrid layer and pressure distribution in soil subgrade (below the geogrid layers) were measured. The test results demonstrate that the ultimate bearing pressure increases with embedment depth ratio of the foundation. With the provision of multiple layers of geogrid reinforcement in the sand bed, high-performance improvement is obtained, in terms of both increase in bearing capacity and reduction in surface deformation. Also, the footing pressure is redistributed more uniformly over a wider area on the subgrade soil. Strain measurements in the geogrid layers indicate that the geogrid reinforcement is more effective in the region below the footing width.

Cet exposé décrit des essais sur modèle de laboratoire visant à déterminer la capacité porteuse d'une assise circulaire enfouie, supportée par des couches multiples delits de sables renforcés par des géogrilles. Nous avons fait varier le taux de profondeur d'enfouissement de l'assise entre zéro et 0,6. Les essais ont été conduits avec une variété de géogrilles dans un sable compacté avec densité relative de 70%. Outre des données d'affaissement de charge, nous avons mesuré les déformations sur la surface de remplissage, les déformations de la couche à géogrilles et la distribution de la pression dans la couche de forme (sous les couches géogrillagées). Les résultats des essais montrent que la pression porteuse ultime augmente proportionnellement avec le taux d'enfoncement de la fondation. Avec plusieurs couches de renfort géogrillagé dans le lit de sable, on obtient une amélioration à haute performance, à la fois en termes d'augmentation de la capacité porteuse et de réduction de la déformation de surface. De plus, la pression de l'assise est redistribuée plus uniformément sur une zone plus vaste sur la couche de forme. Les mesures de déformation dans les couches géogrillagées indiquent que le renfort à géogrille est plus efficace dans la zone située sous la largeur de l'assise.
Seismic behaviour of micropile systems
Authors: Shahrour I. , Juran I.
Published: November 2009

This paper includes analysis of the performance of micropile systems under seismic loading. It presents results of both centrifuge model testing and three-dimensional finite element modelling carried out within the FOREVER research programme. The experimental and numerical results were analysed to study the effect of the main controlling parameters of the micropile-soil-structure systemsuch as the kinematic interaction, the group effect, the influence of micropile inclination, and performance assessment of micropile systems in liquefiable soils. Analysis shows that micropile systems offer effective engineering solutions for construction in seismic areas.

Cette étude est constituée d'analyses de performances pour des systèmes à micropiles soumis à des charges sismiques. Elle présente les résultats d'essais sur modéle centrifuge ainsi que les résultats d'une modélisation en trois dimensions d'éléments finis, le tout effectué dans lecadre du programme de recherche FOREVER. Nous avons analysé les résultats expérimentaux et numériques afin d'étudier l'effet des principaux paramétres de contrôle du système micropile-sol-structure, comme l'interaction cinématique, l'effet de groupe, l'influence de l'inclinaison des micropiles et afin d'évaluer la performance des systémes à micropiles dans des sols liquéfiables. Les analyses montrent que les systémes à micropiles offrent des solutions d'ingénierie efficaces pour la construction dans des zones sujettes aux séismes.
An advanced experimental set-up for studying a monodirectional grout injection process
Authors: Dupla J.-C. , Canou J. , Gouvenot D.
Published: November 2009

In this paper, an advanced experimental set-up is presented for studying the monodirectional grout injection process in sand matrices. The prototype presented is based on the use of sand pluviation for the reconstitution of vertical sand columns (80 mm in diameter and 104 cm in height), which makes it possible to obtain, within the whole column, a good homogeneity of the sand at a controlled preselected state of density. Also, the pore fluid pressure is measured at five equidistant points on the columns, which provides useful information on the injection process. The procedure used to perform a test is described in detail, and the result of a typical test carried out on a medium-size silica sand with a cement-bentonite grout is presented, showing the importance of the filtration mechanism with progressive plugging of the sand matrix for the injection process and for the mechanical properties of the grouted material. Finally, some comments are made on the influence of grain size distribution curve on the injection process.

Dans cette étude, nous présentons un montage expérimental sophistiqué pour é tudier le processus d'injection monodirectionnel d'un coulis dans des matrices de sable. Le prototype présenté est basé sur l'utilisation de la pluviation sableuse pour la reconstitution de colonnes de sable verticales (de 80 mm de diamètre et 104 cm de hauteur) ce qui permet d'obtenir, dans toute la colonne, une bonne homogénéité du sable à un é tat présélectionné et contrôlé de densité. De plus, nous mesurons la pression de fluide interstitiel en cinq points équidistants sur les colonnes, ce qui donne une information utile sur le processus d'injection. La procédure utilisée pour effectuer un test est décrite en détail et nous présentons le résultat d'un test type effectué sur un sable de silice de taille moyenne avec un coulis au ciment bentonite, montrant l'importance du mécanisme de filtration, avec obturation progressive de la matrice sableuse, pour le processus d'injection et pour les propriétés mécaniques du produit cimenté. Enfin, nous faisons certaines observations sur l'influence de la courbe de distribution des dimensions de grains sur le processus d'injection.
Observational method of assessing improvement of marine clay
Authors: Arulrajah A. , Nikraz H. , Bo M. W.
Published: November 2009

The ongoing Changi East Reclamation Project in Singapore consists of land reclamation and ground improvement works of the foreshore for the future expansion of the Changi International airport and associated facilities. Reclamation works in the project involve the hydraulic placement of sand-fill over the seabed, which is underlain by thick, highly compressible Singapore marine clay. Ground improvement works in the project comprise the installation of vertical drains and the subsequent placement of surcharge to accelerate the consolidation of the underlying marine clay. A pilot test site was carried out in the project, comprising three sub-areas that were installed with vertical drains at various spacings, plus a fourth untreated sub-area. The four sub-areas were surcharged simultaneously and preloaded for a duration of 32 months. A comprehensive field instrumentation programme was implemented in the pilot test site, comprising settlement plates, deep settlement gauges, piezometers and water standpipes. The degree of improvement attained by the foundation soil at each sub-area was determined and assessed during the process of consolidation and 32 months after surcharge placement using the observational method. This paper describes the applications and comparisons between the Asaoka method, the hyperbolic method and piezometers in monitoring the improvement of marine clay under reclamation fills.

Le projet de récupération de terre qui se poursuit à Changi East à Singapour consiste en une récupération des terres et une amélioration des sols du littoral dans le but d'agrandir l'aéroport international de Changi ainsi que ses installations associées. Les travaux portent sur la mise en place hydraulique d'un remblai de sable sur le fond de mer, qui est recouvert d'une argile marine é paisse, très compressible, de Singapour. Les travaux d'amélioration des sols consistent à installer des drains verticaux et à leur imposer ensuite une surcharge afin d'accélérer la consolidation de l'argile marine sous-jacente. Un site d'essai pilote a é té réalisé dans le projet, comprenant trois sous zones qui ont é té é quipées de drains verticaux placés à diverses distances les uns des autres et une quatrième sous zone non traitée. Les quatre sous zones ont subi une surcharge simultanée et une pré-charges pendant 32 mois. Un programme d'instrumentation complet sur le terrain a é té mis en uvre dans le site d'essai pilote, comprenant des plaques de tassement, des jauges profondes d'affaissement, des piézomè tres et des remontées d'eau. Le degré d'amélioration atteint par le sol de fondation dans chacune des sous zones a été déterminé et é valué pendant le processus de consolidation et 32 mois après le placement de la surcharge en utilisant la méthode observationnelle. Cet exposé décrit les applications et comparaisons entre la méthode Asaoka, la méthode hyperbolique et les piézomètres pour suivre l'amélioration de l'argile marine sous remblais de récupération.
Model testing of strip footings with structural skirts
Authors: Al-Aghbari M. Y. , Mohamedzein Y. E.-A.
Published: November 2009

Tests on footing models were carried out to study the behaviour of strip footings with structural skirts resting on sand. The use of structural skirts improved the bearing capacity of strip footings by a factor of up to three. The improvement depends on the geometrical and structural properties of the skirts and footing, and the soil characteristics and interface conditions of the soil-skirt-foundation system. To account for these factors, a modified bearing capacity equation was proposed for skirted strip foundations on dense sand by the authors. The predictions of the proposed equation are in excellent agreement with the experimental results. The experimental results showed that the use of structural skirts reduced the settlement by a factor of up to three depending on the skirt depth, geometrical properties of the skirt and footing, soil characteristics and the applied load. The structural skirts modified the load-settlement curve for the footing by increasing the strain at failure to about 22%.

Nous avons fait des essais sur des modèls d'assises afin d'étudier le comportement d'assises à bandes avec des jupes structurales reposant sur du sable. L'utilisation de jupes structurales a amélioré la capacité porteuse des assises à bande par un facteur de 3. L'amélioration dépend des propriétés géométriques et structurales des jupes et des assises ainsi que des caractéristiques du sol et des conditions d'interface du système sol-jupe-fondation. Pour rendre compte de ces facteurs, les auteurs proposent une é quation modifiée pour la capacité porteuse des fondations à jupe sur du sable dense. Les prédictions de l'équation proposée sont en accord parfait avec les résultats expérimentaux. Les résultats expérimentaux ont montré que l'utilisation de jupes structurales réduisait le tassement par un facteur allant jusqu'à 3, selon la profondeur de la jupe, ses propriétés gé ométriques et son assise, les caractéristiques du sol et la charge appliquée. Les jupes structurales modifiaient la courbe charge-tassement pour l'assise en augmentant la déformation à la rupture jusqu'à environ 22 %.
Uniformity of lime-cement columns for deep mixing: a field study
Authors: Larsson S. , Dahlström M. , Nilsson B.
Published: November 2009

A field study of the mixing process of lime-cement columns for deep mixing has been carried out at a test site in Håby, Sweden. The study aimed to investigate the influence on the stabilisation effect and the coefficient of variation for excavated columns, when a number of factors related to the installation process were varied. The influencing factors investigated were the retrieval rate, number of mixing blades, rotational speed, air pressure in the storage tank, and diameter of the binder outlet hole. A large number of hand-operated penetrometer tests were carried out on the excavated column cross-sections. Statistical multifactor analyses were used to evaluate the influence on the stabilisation effect and the coefficient of variation of the varied factors. The results showed that the retrieval rate and the number of mixing blades were found to have a significant effect. The effect of rotational speed and the diameter of the outlet hole were found to be insignificant. The field study showed that the strength and deformation properties of the soil and the upper pair of mixing blades, with respect to the binder outlet hole, had a major influence on the binder dispersion over the column cross-section. The blade rotation number can be used as an indirect value of the mixing work and can be used as a measure of the mixing tool effectiveness.

Nous avons réalisé une étude de terrain sur le processus de mixage des colonnes chaux-ciment à mixage profond sur unsite d'essai de Håby en Suède. L'étude avait pour but de déterminer ce qui se passait pour l'effet de stabilisation et le coefficient de variation, pour des colonnes excavées, lorsqu'un certains nombre de facteurs liés au processus d'installation étaient variés. Les facteurs étudiés étaient le taux de récupération, le nombre de pales de mixage, la vitesse de rotation, la pression de l'air dans la cuve de stockage et le diamètre du trou de sortie de l'agent liant. Nous avons réalisé de nombreux essais au pénétromètre manuel sur des coupes de colonnes excavèes. Nous avons utilisé desanalyses statistiques multi-facteurs pour é valuer l'influence sur l'effet de stabilisation et le coefficient de variation de ces facteurs variés. Les résultats ont montré que le taux de récupération et le nombre de pales de mixage avaient un effet significatif. L'effet de la vitesse de rotation et du diamètre du trou de sortie sont apparus comme insignifiants. L'étude sur le terrain a montré que la résistance et les propriétés de déformation du sol ainsi que la paire supérieure de pales mélangeuses, par rapport au trou de sortie de l'agent liant, avaient une influence majeure sur la dispersion de l'agent liant sur la coupe transversale de la colonne. Le nombre de rotations des pales peut être utilisé comme valeur indirecte du travail de mixage et peut être utilisé comme mesure de l'efficacité de l'outil de mixage.
Reclamation and soil improvement on ultra-soft soil
Authors: Bo M. W. , Choa V. , Wong K. S.
Published: November 2009

In recent years more and more reclamations have been carried out on waste ponds or mine tailing ponds. The deposits in these ponds are ultra-soft and may still be undergoing self-weight consolidation. Reclamation and soil improvement works in these areas are very challenging. They require special attention. Conventional reclamation and soil improvement methods are no longer workable. This paper highlights the experience obtained from reclamation and soil improvement works on such soil in a project in Singapore. The fill was placed using a sand spreader, and the ultra-soft deposit was strengthened with a high-strength geotextile. Prefabricated vertical drains and staged construction were used to accelerate the consolidation process. The monitoring of settlement and pore pressure requires modification of conventional instruments to cater for the low strength of the ultra-soft soil and the large strain of deformation. The paper also outlines a new method to estimate the settlement based on large-strain theory. Finally a case study is presented to validate the proposed method in the determination of settlement magnitude and the time rate of settlement.

Depuis quelques années, on récupè de plus en plus de terrains sur les bassins de rejets ou les bassins de décharge des mines. Les dépô ts de ces bassins sont extrêmement mous et peuvent même ê tre en cours de consolidation autochargée. Les travaux de récupération et d'amélioration des sols dans ces zones posent beaucoup de problémes. Ils demandent une attention spéciale. Les méthodes conventionnelles de récupération et d'amélioration ne sont pas efficaces. Cet exposé présente l'expérience obtenue apre's des travaux de récupération et d'amélioration de ces sols dans un projet à Singapour. Le remblai é té placé en utilisant une dispersion de sable et le dépô t mou a é té renforcé par un géotextile à haute résistance. Des drains préfabriqués verticaux et une construction é tagée ont é té utilisés pour accélérer le processus de consolidation. Le suivi du tassement et de la pression interstitielle demande la modification des instruments conventionnels afin de prendre en compte la faiblesse du sol mou et la grande déformation. Cet exposé présente aussi une nouvelle méthode basée sur la théorie de grande déformation et servant à é valuer le tassement. Enfin nous présentons une é tude de cas pour valider la méthode proposée pour déterminer la magnitude du tassement et la durée du tassement.
Field performance of fly ash stabilised subgrades
Authors: Parsons R. L. , Kneebone E.
Published: November 2009

Class C fly ash has been used to improve the properties of subgrade soils for several decades. This report contains a summary of the results of a study to quantify the level of improvement provided by Class C fly ash and the degree to which those improvements are effectively permanent. A series of dynamic cone penetrometer values were obtained for 12 streets with fly ash treated subgrades, and for five streets with untreated subgrades. Streets ranged in age from zero to nine years. For subgrades with fly ash the penetration resistance was recorded for the fly ash treated layer and the untreated soil beneath. Higher strengths were recorded for all fly ash treated subgrade layers than for the untreated soil beneath. No deterioration with age was observed for the subgrades evaluated. Laboratory and field testing of soils treated with fly ash also showed that fly ash contributed to soil strength and stiffness while plasticity and swell potential were reduced, although swelling was not eliminated.

La cendre volante de classe C est utilisée depuis plusieurs décennies pour améliorer les propriétés des fonds de forme. Ce rapport résume les résultats d'une é tude visant à quantifier le niveau d'amélioration apporté par la cendre volante de classe C et le degré de permanence de ces améliorations. Une série de valeurs obtenues par pénétromé tre à cone dynamique a é té obtenue dans 12 rue possédant des fonds de formes traités à la cendre volante et dans cinq rues avec fonds de forme non traitées. Les rues avaient de zéro à neuf ans. Pour les fonds de forme traités à la cendre volante, la résistance à la pénétration a é té enregistrée pour la couche traitée à la cendre volante et pour le sol non traité en dessous. Pour toutes les couches de fonds de forme traitées à la cendre volante, des résistances plus é levées ont é té enregistrées que sur le sol non traité en dessous. Aucune détérioration due à l'âge n'a é té observée pour les fonds de forme é valués. Les essais de terrain et en laboratoire sur sols traités à la cendre volante ont montré que la cendre volante contribuait à la résistance et à la rigidité du sol tandis que la plasticité et le potentiel de gonflement se trouvait réduit, bien que le gonflement ne soit pas totalement éliminé.
Numerical simulation of geocell-reinforced sand and clay
Authors: Saride S. , Gowrisetti S. , Sitharam T. G. , Puppala A. J.
Published: November 2009

A numerical simulation of laboratory model tests was carried out to develop an understanding of the behaviour of geocell-reinforced sand, and soft clay foundation beds under a circular footing. The influence of the geometrical parameters of the geocell (width, b and height, h) on the overall performance of the footing was investigated and the pressure–settlement responses of geocell-reinforced foundation beds were predicted and compared with the unreinforced test results. Simulations were also carried out on conventional-type planar geogrid reinforcement to study the relative performance of both reinforcement forms. The influence of the boundary constrains on the behaviour of the foundations was also studied. In all the cases, good agreement between the results obtained from numerical simulations and laboratory experiments was observed. The results demonstrated that the geocell mattress redistributed the footing pressure over a wider area thereby improving the performance of the footing. The pressure–settlement responses corresponding to geocell-reinforced beds were found to be much stiffer in comparison with the unreinforced case indicating that a substantial reduction in footing settlement can be ascertained. The influence of rigid boundaries on the results of reinforced foundation beds in this study was found to be negligible.
Bleeding and channelling in bored piles
Authors: Kog Y.C.
Published: November 2009

Bleeding is known to occur in bored piles. The generally accepted view is that bleeding in piles is confined to the upper part of the pile only. Extensive integrity tests consisting of 244 sonic logging tests and 80 dynamic load tests on bore piles as well as continuous corings from top to bottom of the piles revealed that some 28 bored piles were found to have channelling of concrete at various depths. Most of them were larger diameter piles. This paper attempts to propose a theory for the bleeding and channelling of concrete to explain the mechanics of the occurrence of channelling in bored piles. The theory is verified by the close correlation of the predictions of the theory with field observations of the integrity tests. Based on the proposed theory, recommendation with regards to the quality of concrete will be made to avoid the occurrence of channelling of concrete in large diameter bored piles.
A new steel jacketing method for RC columns
Authors: Choi E. , Park J. , Nam T.-H. , Yoon S.-J.
Published: November 2009

This paper introduces a new steel jacketing method for reinforced concrete (RC) columns with lap splice and evaluates its performance by a series of axial tests of concrete cylinders. At first, 45 concrete cylinders were fabricated with varying design compressive strengths of 21, 27 and 35 MPa and then part of them was jacketed with two split-steel jackets under lateral confining pressure. The parameters in the first test were the steel jacket's thickness and the existence of adhesive between steel and concrete surface. In the second test, whole steel jackets were used to wrap cylinders with lateral pressure. Also, a double-layered jacket consisting of two steel plates was introduced; a cylinder was jacketed by two steel plates one after another. The effect of the new method was verified through comparing the results of the compressive tests for plain and jacketed cylinders. The steel jacket built following the new method showed good results of increasing the compressive strength and ductility of the jacketed cylinders with respect to the plain cylinders. The thicker steel jackets showed that the increased compressive strength, and the ductility at failure depended on the welding quality of the steel jackets. The adhesive between steel and concrete surface reduced the confining effect of the steel jackets. The whole jacket showed more ductile behaviour than the two split jackets. The double-layered jackets were estimated to possess an equal performance to that of a single steel jacket having the same thickness of the double-layered jacket. Finally, the experimental results were compared with the constitutive model of steel-jacketed concrete; which showed a good agreement between the experimental results and the models.
Shear strength of reinforced concrete corbels
Authors: Lu W.-Y. , Lin I.-J. , Hwang S.-J.
Published: November 2009

In this study, 15 reinforced concrete corbels with shear span-to-depth ratio greater than unity were tested. Test results indicate that the shear strength of corbels increases with increase in compressive strength of concrete, parameter of main reinforcement and parameter of vertical stirrups. The shear strength of corbels also increases with decrease in shear span-to-depth ratio. An analytical model for determining the shear strength of reinforced concrete corbels is also proposed in this paper. Both the shear strengths predicted by the proposed model and the approach of the ACI code are compared with available test results. The comparison shows that the proposed model can predict more accurately the shear strength of reinforced concrete corbels than the approach of the ACI code.
Saltmarsh loss and maintenance dredging in estuarise
Authors: Pontee N. I.
Published: November 2009

The removal of sediment from estuaries by maintenance dredging has the potential to be detrimental to habitats such as saltmarshes. This paper examines the case for environmental reparation with respect to maintenance dredging activities in two estuaries within the western Solent in England. These two examples suggest that the detrimental impacts of maintenance dredging and requirement for beneficial use schemes may have been overstated in some areas of the UK. The examples also demonstrate that beneficial use schemes themselves can potentially have deleterious impacts on estuary systems and therefore should not be viewed as a universal panacea for estuary management.
Determination of the efflux velocity from a ship's propeller
Authors: Hamill G. A. , McGarvey J. A. , Hughes D. A. B.
Published: November 2009

The wash produced by a ship's rotating propeller is known to cause scouring of the seabed. The design of suitable armour units to prevent such scouring requires an understanding of the velocities within the wash. Key to predicting velocity at any position within the wash is an accurate method for determining the maximum velocity as the wash exits the propeller. This value is known as the efflux velocity. This paper details a study that was undertaken to provide a means by which a more accurate estimation of this velocity can be obtained.
Accounting for random wave run-up in overtopping predictions
Authors: Hedges T. S. , Reis M.T.
Published: November 2009

The paper describes a method for predicting the rates of overtopping of seawalls by random waves. The procedure links the overtopping rate to information on wave run-up. Output from the procedure is compared with physical model data not used in its original calibration, and with the results from two other methods commonly employed for predicting overtopping discharges. The output is shown to be in good agreement with the new data, despite the fact that these measurements cover a much wider range of incident wave steepnesses and storm durations than those used in the original calibration. The method is also shown to predict lower overtopping rates than the two alternative procedures for both low and high relative seawall freeboards, together with similar or higher overtopping rates in the middle range of free-boards for which most physical model data are available.
Modelling directional random wave propagation inshore
Authors: Kuang C.-P. , Stansby P.K.
Published: November 2009

Long-term nearshore wave climate prediction requires an efficient solution method for the propagation of directional random waves from offshore. Predictions of laboratory data for waves over submerged shoals indicate that waves with broad, but not narrow, directional spread are well predicted without taking diffraction into account, and an efficient parabolic, ‘ray-tracing’ solver may thus be used. Application to the complex coastal bathymetry off East Anglia indicates that inshore wave climate is generally only slightly affected by the degree of directionality, tidal currents, and wind forcing over the propagation region. It thus seems realistic to define inshore wave climate for a range of offshore conditions, defined only by wave height, period and direction, and of course tidal level, using an efficient parabolic solver.
Seismic response of a rubble mound breakwater in Turkey
Authors: Yüksel Y. , Çetin K. Ö. , Özguüven O. , Isik N. S. , Cevik E. , Sümer B. M.
Published: November 2009

This paper presents analyses of seismically induced deformations at Ereğli Fishery Port breakwater during the 1999 Kocaeli (İzmit), Turkey earthquake. The paper discusses: (a) observed ground deformations and displacements after the earthquake; (b) the results of field investigations by means of borings including standard penetration tests; (c) analyses of observed deformation mechanisms by a suite of methods; and (d) the possible contribution of soil liquefaction rupture on the observed deformations.
Modelling wave reflection on sloping foreshores with sea walls
Authors: Lawrence J. , Chadwick A. J.
Published: November 2009

This paper presents the findings of a study on the mechanics of wave reflection on sloping foreshores with sea walls. A series of numerical experiments have been performed using a weakly non-linear 1-D finite difference model of the Boussinesq equations. The capabilities of the model have been investigated and the underlying hydrodynamic processes assessed. The model has also been tested against full-scale experimental data. The results show that a Boussinesq model can be used to model the wave field in front of a reflecting structure with good accuracy. Further analysis of this situation shows that the cross-shore profile of the wave velocity skewness for this case is a function of the nature of the sloping bed. These changes in skewness will have a significant effect on the morphodynamics of the foreshore.
Planning and implementing coastal management in Sri Lanka
Authors: Hettiarachchi S. S. L. , Samarawickrama S. P.
Published: November 2009

Sri Lanka is one of the island states to have developed very early, and operated fully, a coastal management plan on a national scale. The Coast Conservation Department, by Act of Parliament, has full responsibility for the implementation of the plan. The plan is periodically revised to incorporate emerging challenges, current and projected development trends, in refining policies and guidelines. The paper presents a review of planning and implementation of the coastal zone management in Sri Lanka. It focuses on the approach to coastal zone management via regulation of development activities and environmental protection, second-generation and current initiatives, challenges and constraints. The paper concludes with the future outlook, focusing on the role of the Coast Conservation Department and the relevance of the use of integrated coastal zone management frameworks.
Using NEC contracts to manage risk and avoid disputes
Authors: Patterson R.
Published: November 2009

NEC contracts provide an excellent basis to encourage and support risk management through all stages of any project or service provision. Partly because they are good for risk management, NEC contracts have anecdotally helped avoid disputes. After more than 12 years of use for possibly billions of pounds worth of work in probably tens of thousands of projects in more than 20 countries there remains only one piece of case law relating to the use of the NEC. The aim of this paper is to explain how NEC contracts can be used to reflect the particular risk allocation intended by the parties to the contract through the use of the options within the contract. It then explains the key tools and processes in the contract for the ongoing management of risk, including the NEC’s ‘Risk Register’ and the allocation of risk in quotations for the effects of events at the client’s risk.
Engineer’s role in resolving disputes in offshore projects
Authors: Ma A.
Published: November 2009

Offshore construction and supply projects involve complex contractual arrangements regulating the relationships of operators, contractors, subcontractors and suppliers. Although every effort is made to prevent the occurrence of disputes when parties enter into contract, it is a fact of life that disputes do arise. This paper explains the role of engineers in the dispute resolution process. It highlights the features of disputes which arise out of the offshore construction and supply industry by way of inclusion of a description of: the life cycle of a typical offshore development; a typical engineering, procurement, construction, installation and commissioning project; the engineer’s involvement in the contractual process; types of frequently occurring disputes; and the role of engineers in dispute avoidance. By way of introducing the various methods of disputes resolution, including litigation, arbitration, adjudication, expert determination, mediation, the engineers’ functions in these processes are highlighted.’The paper concludes that engineers are indeed important if not crucial to every stage of an oil and gas construction project. They have every opportunity to assist in dispute avoidance by being more aware of the contractual relationship between various parties and the project procedure. They can be factual witnesses to set out the chain of events that happened, expert witnesses to assist the court or tribunal in understanding the technical issues, and they are also well placed to judge the rights and wrongs of the parties given their technical backgrounds in understanding the day-to-day running of a project.
Measurable success in best value
Authors: Bovaird T.
Published: November 2009

The best value pilot initiative in local government was launched in 1997 and securing best value in the delivery of services is a statutory duty upon local authorities from April 2000. This paper explores how these pilot initiatives have fared to date and how their success might be measured. It explores the meaning of ‘best value’, the way in which the National Evaluation Team is assessing the performance of the pilots and the Government's performance indicators for best value.
Best value and management practice in local government: a reality check
Authors: Wills N.
Published: November 2009

This paper is an assessment of best value and how it needs to be implemented. The tools which have been developed to help councils and their heads of service are described. The purpose of this paper is to discuss problems and propose solutions.
City of Lincoln Best Value Pilot—the aftermath
Authors: Shardlow R.
Published: November 2009

This paper outlines the course of action that the City of Lincoln has pursued following the award of Best Value Pilot status. The paper focuses on the corporate roll-out of best value, the review of corporate aims, the re-alignment of services to corporate aims, service reviews, and the outcome of the Best Value Pilot.
Transport planning performance indicators, democracy and best value
Authors: Nisbet A.
Published: November 2009

The duty of best value requires local authorities to provide services that are in tune with the needs and wishes of their communities. At the same time, the Government requires local authorities to develop local transport plans that comply with national policy on integrated transport. However, there is evidence to suggest that the transport system that local communities want does not necessarily meet the guidelines set by central government. As part of the best value process, local authorities will be measured against a series of performance indicators. Critically, for transport, no strategic indicator has been suggested. This is curious since transport planners have considerable experience of setting strategic objectives and evaluating their plans against them. The local transport plan system could be developed to double as a performance plan for transportation and, through this, the development of local solutions could provide feedback to inform and develop national policy.
Finding the finance—a perspective on the issues surrounding public–private wastes management partnerships in the era of best value
Authors: Kilduff D.
Published: November 2009

The purpose of this paper is to examine some of the issues that influence authorities wishing to secure funding for major waste management projects in a commercial, effective and affordable way. In doing so, the paper will reflect upon background issues that influence the way in which such schemes are brought to the market as well as waste and sustainable development policy. The recently published National Waste Strategy for England and Wales and the continuing impact of EU and domestic legislation (including the effect of landfill tax) will be a major driving force for the promotion of innovative and integrated waste management solutions.
Sustainable reuse of highway materials in hot and cold bituminous mixtures
Authors: Woodside A. R. , Woodward W. D. H. , Phillips P. , Mills A.
Published: November 2009

In the last few years there has been growing concern about the increasing demand placed upon finite resources. Many organizations and types of industry now encourage the practice of sustainability. With the introduction of the landfill tax, aggregate tax and the increasing cost of bitumen, highway authorities must now consider other methods to achieve better value for money. In highway engineering, reduction in use of aggregate and bitumen resources can be achieved by better understanding of pavement design and choice of materials used. It may also be facilitated by the reuse of bituminous materials that have been removed from the pavement structure as part of a maintenance programme. This is termed reclaimed asphalt pavement (RAP) and is permitted in hot-mix asphalt in accordance with the Specification of Highway Works Clause 902. A combination of these two approaches will enable the maximum reuse of this type of material without turning the highway into what may be termed a waste disposal location. This paper shows how clients such as local highway authorities are maximizing reuse opportunities. It also gives an example of how suppliers are now collaborating with academic institutions to develop new technologies to solve the client's problem. Two experimental trial road sections are detailed which were designed and constructed to evaluate the use of RAP in a hot and a cold bituminous mixture. This has enabled the authors to quantify the benefit of using recycled materials and technologies.
Community involvement—the role of the community engineer
Authors: Planner B. C.
Published: November 2009

Consultation and community involvement are becoming an ever more important aspect of the delivery of public services. This paper draws attention to the key aspects of a consultation strategy being developed by Swale Borough Council and the methods that can be applied to undertake consultation and effectively involve the community in the delivery of services. The paper provides examples of projects carried out within the council's Engineering Services Unit where engineers have played an increasingly important role in involving the community in the delivery of projects and services. The paper also discusses the politician's role in the consultation process.
Community involvement—a politician's perspective
Authors: Varden A.
Published: November 2009

This paper assesses the increasing importance of the consultation process when planning new engineering projects with particular reference to the Integra Project in Hampshire.
Time to rethink?
Authors: MacGregor R.
Published: November 2009

Rethinking Construction, the 1998 report of the Construction Task Force, has established a radical new agenda to improve UK construction performance. This paper explains the work of the Local Government Task Force in seeking to deliver the Rethinking Construction agenda to local authorities.
Innovative partnership: Dorset County Council and Buro Happold
Authors: Winter M.
Published: November 2009

The Department of the Environment, Transport and the Regions' Guide to Best Value, Circular 10/99 lists a range of possible future service delivery options that should be considered as part of any best value review. One such option is the creation of a public/private partnership. This paper describes the steps taken by Dorset County Council to form an innovative, strategic alliance between its engineering consultancy division and the private sector consultant, Buro Happold.
Partnering with community—an option for infrastructure procurement
Authors: Sohail M. , Baldwin A.
Published: November 2009

This paper is about community partnered procurement (CPP) of infrastructure. It looks at a changing role for the community in a general sense, but for householders in settlements in particular. The paper puts CPP in the broad context of different procurement options. It describes the mechanisms, both conventional and unconventional, governmental and non-governmental, that have been adopted to deliver improved urban services in partnership with community. The mechanisms and processes of agreements, procedures and contracts, which are the basis for implementation of infrastructure improvement in low-income communities, are also introduced. The specific focus of the paper is the situation where communities have undertaken the role of the contractor. The paper provides both general experience and case study evidence from Sri Lanka, Pakistan and India. The potential benefits and implications of adopting CPP are described.
Appropriate wastewater collection, treatment and reuse in developing countries
Authors: Mara D.
Published: November 2009

Some two billion people in developing countries lack adequate sanitation. In the low-income high-density periurban areas of cities and towns (and the world is periurbanising rapidly), often the most appropriate technical solution to wastewater collection is simplified sewerage—small-diameter sewers laid in-block at fairly flat gradients; for example, a 100 mm diameter sewer laid at a gradient of 1 in 200 can serve around 1000 people at low cost. Four billion people lack waste-water treatment—that is, around two-thirds of the world's population. Most of these four billion live in developing countries where energy-intensive electromechanical wastewater treatment, of the type favoured in industrialised countries, is too expensive and too difficult to operate and maintain. In many situations in developing countries more appropriate technologies will have to be used. These include: waste stabilisation ponds, upflow anaerobic sludge blanket reactors, wastewater storage and treatment reservoirs (or some combination of these). High-quality effluents can be produced which are especially suitable for crop irrigation and fish culture. In the twenty-first century ‘from sewage to soya’ will have to become more common as the world's population relentlessly increases.
Increasing car dependency of children: should we be worried?
Authors: Mackett R. L.
Published: November 2009

Children are becoming increasingly dependent on the car. This is occurring because of the complexity of modern life and the resulting shortage of time which often means that a child is taken to school by car, sometimes as part of a longer trip. Many parents are concerned about the safety and security of their children. The weather also plays a key role. This increasing car use by children has several implications: children lose opportunities to gain road-based skills and independence from their parents; they lose some social opportunities; parental time is spent taking children by car; there is extra traffic on the road, particularly during the morning peak; children will have a reduction in their physical activity, which has health implications; and, they may grow up with little or no experience of using alternatives to the car. This will have significant adverse impacts on future policies aimed at reducing car use. The situation is likely to worsen. Car ownership will increase further, with a greater increase in households with children than those without. Car use by children is likely to increase considerably. This is a very worrying trend.
Marketing and the British bus industry
Authors: Enoch M. , Potter S.
Published: November 2009

The development of public transport services is a key element of all local sustainable transport strategies. Achieving modal switch from car users requires marketing systems be changed to identify and target suitable non-users of public transport, rather than just enlarging custom by existing users. However, in the public transport field, marketing is still essentially designed to only address the existing customer base. This is particularly acute among bus operators, who rarely even market effectively to their existing customer base, and have a poor image among car users. This paper draws on the practical experience of some of the relatively few local bus operators and local authorities that have identified and won new markets, including modal shift from car. It looks at the sort of services they have developed, the marketing strategies adopted, and at how the stake-holders worked together. In addition, it provides hard evidence as to the benefits of marketing bus services properly, suggesting that patronage gains of around 5–7% should be possible, even without major investment or legislative change. In conclusion, seven key features of good practice are identified that need to be part of developing bus services to serve sustainable transport policies. These are customisation, co-operation, clear vision, clarity (to the user), core market, culture, and continuity.