bluuebunny/crossref_metadata_2025 huggingface dataset:
State of the art in deep mixing technology: part I. Basic concepts and overview
Authors: Porbaha A.
Published: July 2016

Today’s competitive construction industry is highly dependent on effective use of existing and innovative technologies. In many situations the key issue is not how to break through technological barriers but how to put existing concepts to the best possible use. Whereas the basic knowledge behind many developed techniques can be found in engineering textbooks, the complex issues related to know-how of analysis and design, construction techniques, and quality monitoring, developed based on regional experiences, have not been widely available to engineers working in different countries. In a series of papers, the aim is to examine issues, concepts, and the latest advancements in research and development of deep soil mixing technology. The focus is on presenting basic concepts, various application areas, considerations for analysis and design, construction techniques, methods of quality control, and so on. A large number of case histories of deep mixing projects, applied in different countries, are collected to portray various functions of deep mixing; along with references to exemplify the current practice and the present understanding of the technology. This first paper emphasizes basic concepts, definitions, classifications, and historical developments related to deep mixing technology around the world.
Shear strength characteristics of some Indian fly ashes
Authors: Sridharan A. , Pandian N. S. , Srinivasa Rao P.
Published: July 2016

Thermal power stations using pulverized coal as fuel produce enormous quantities of ash as waste products of combustion. In India, it is estimated that thermal power plants will produce about 100 million t of flyash per year by the year 2000. Hence the problem of ash disposal is expected to become acute due to the limited space available for ash disposal near most of the power plants. This calls for strategies to encourage and establish technological concepts for bulk utilization of fly ash which should not only be cost-effective but also environment friendly. This paper reports an experimental programme carried out to study the shear strength characteristics of fly ash using direct shear tests under different conditions so as to enable its bulk utilization in geotechnical engineering applications. The results are encouraging due to the low unit weight, good frictional properties, low compressibility and high permeability of fly ash.
Quality control of jet grouting on the Cairo metro
Authors: Morey J. , Campo D. W.
Published: July 2016

This paper presents a review of the jet grouting works of Line 2 of the Greater Cairo metro system. During the project over 80 000 m3 of ground was treated using the jet grouting method, making this one of the largest jet grouting endeavours worldwide to date. Demanding design requirements for the various jet grouting applications coupled with the difficult Cairo ground conditions provided new challenges to the current jet grouting technology. Inherent difficulties with jet grouting were identified when relying on the method for watertightness at great depths. This paper summarizes the main jet grouting applications used on Line 2 of the Cairo metro and the quality control solutions implemented to overcome difficulties in the work.
Compaction behaviour of fly ashes
Authors: Prashanth J. P. , Sivapullaiah P. V. , Sridharan A.
Published: July 2016

Fly ashes are used widely in many geotechnical applications. In most of the applications, compaction of the fly ashes is essential to improve their engineering behaviour. This paper presents the compaction behaviour of fly ashes along with the mechanisms controlling their behaviour. To this end, their compaction curves have to be presented on recently proposed volume-based parameters, namely solid volume occupation and water volume content, instead of weight-based parameters such as dry density and water content. For a given fly ash the variation in solid volume occupation with water volume content for any given compactive effort has been explained as being due to variation in the pore water pressure. Fly ashes resist the external compactive effort by shear resistance and positive pore water pressure development. The strength of fly ashes at any point on the dry side of optimum is the same, and on the wet side of optimum decreases with water volume content. The variation between the compaction curves of different fly ashes is essentially due to their differences in fineness and frictional characteristics.
Laboratory-scale soil mixing of a contaminated site
Authors: Al-Tabbaa A. , Evans C. W.
Published: July 2016

The interpretation of the results of full-scale testing of treated contaminated ground and the correlation of these results with those from laboratory treatability studies are complex because of site heterogeneities, both in terms of the soils and the contaminants. In addition, the high costs usually associated with full-scale testing make laboratoryscale model testing of site conditions an effective means of correlating laboratory and in situ results. This paper presents details of laboratory-scale modelling of an in situ soil-mixing treatment of a contaminated site, for which a laboratory treatability study and a full-scale pilot in situ treatment had been carried out. The objective was to develop a correlation between full-scale soil mixing, laboratory-scale soil mixing and the laboratory treatability study. The correlation is presented in terms of physical and chemical properties, namely unconfined compressive strength, leachability, leachate pH, durability, permeability, compressibility and microstructural analyses. The results showed that reduced-scale laboratory modelling of in situ soil mix treatment of contaminated soils should be an integral part of the treatability study. The modelling was successful in duplicating certain in situ conditions which were not possible with conventional treatability study procedures.
Deep soil mixing used to reduce embankment settlement
Authors: Bergado D. T. , Ruenkrairergsa T. , Taesiri Y. , Balasubramaniam A. S.
Published: July 2016

Severe settlement and stability problems characterize the problems of the 55 km Bangna–Bangpakong Highway in Thailand. To rehabilitate this major arterial road, the deep mixing method (DMM) with soil–cement using ordinary Portland cement has been utilized for foundation improvement. In the laboratory, trial mix designs were used with a specified unconfined compressive strength of 1000 kPa. In the field, the unconfined compressive strength of the cement piles was specified at 600 kPa. Detailed soil investigations and subsequent evaluations for Section 3 from km 28 + 000 to km 34 + 500 were done. Analyses were performed regarding the bearing capacity, total settlements and their rates, and stability analyses. The predicted vertical and horizontal deformations were compared and generally agreed with the corresponding values observed in the field.
Assessment of stabilised soil strength with geophysical methods
Authors: Åhnberg Helen , Holmén Martin
Published: July 2016

Soil stabilisation by deep mixing is performed to improve the strength and compression properties of soft soils. The determination of strength and of deformation moduli of stabilised soils in the laboratory can be performed in different ways. In addition to the unconfined compression test, which is the most common method for routine testing, seismic non-destructive methods may be employed. In order to evaluate strength parameters from these methods, correlations between the wave velocity and the undrained shear strength are required. At the Swedish Geotechnical Institute, the unconfined compression tests have routinely been preceded by shear wave velocity measurements with bender elements and resonant column free-free test to determine the shear wave and compression wave velocities in the same test specimens. This has allowed comparisons to be made of the results obtained with the two test methods. Fairly good and reliable relations between shear wave velocity and undrained shear strength have been established for stabilised clays of initial medium and high plasticity.
Seismic-resistant effect of cement-treated soil for quay wall
Authors: Takahashi Hidenori , Kitazume Masaki , Noguchi Takatoshi , Suzuki Noriyoshi
Published: July 2016

The application of cement-treated soil as a backfill material is becoming more common in Japan. The large shear strength of treated soil can reduce the earth pressure acting on the wall. In the present study, a series of dynamic shaking model tests using a centrifuge facility was performed to investigate the seismic characteristics of the sheet pile quay wall backfilled with the treated soil. In the case of subjection to horizontal seismic force the characteristics of vibration and earth pressure of treated soil are so complicated that the improvement effects of treated soil have not been clarified yet. In addition, the treated soil is anticipated to fail with tensile cracking due to its brittle characteristics, because the treated soil cannot follow any large deformation of the surrounding soft ground. The model tests revealed the failure mode of improved ground and the effects on the deformation behaviour of a crack and dimensions of cement-treated soil.
QA/QC for deep-mixed ground: current practice and future research needs
Authors: Terashi M. , Kitazume M.
Published: July 2016

The quality of deep-mixed soil (improved soil by in situ mixing) depends upon a number of factors including the type and condition of native soil, the type and amount of binder, and the production process. The quality assurance/quality control (QA/QC) practice which focuses upon the quality of deep-mixed soil was originally established in Japan and Nordic countries and has been accepted worldwide for more than three decades. It comprises a laboratory mix test, field trial installation, monitoring and control of construction parameters during production and the verification by measuring the engineering characteristics of deep-mixed soil either by unconfined compression tests on core samples or by sounding. Diversification of application, soil type and execution system, together with the improved understanding on the behaviour of deep-mixed ground in the past two decades make it necessary for our profession to review the current QA/QC practice. Based on the literature review and the International collaborative study, the authors discussed the similarity and differences in the QA/QC procedures employed in different parts of the world and proposed the future research needs in a keynote lecture at Okinawa 2009 Deep Mixing Symposium. The current paper is a summary of this keynote address.
Non-destructive technique for assessing cement-treated ground
Authors: Asaka Yoshiharu , Abe Tohru
Published: July 2016

A new, non-destructive technique for investigating the strength of cement-treated ground has been developed. The technique is based on the relationship between the unconfined compressive strength, qu, and the shear wave velocity, Vs, of cement-treated soil. Based on the Vs–qu relationship, the in situ strength of cement-treated ground can be estimated non-destructively and immediately by measuring the Vs value of the ground using bender elements in the field. To demonstrate the effectiveness of this technique, the ground at two actual construction sites was investigated using the technique. The variation coefficient of the measured Vs values ranged from 0·1 to 0·15, and was independent of the curing time and original soil type. The variation coefficient of the Vs values was smaller than that of the unconfined compressive strength estimated by conventional unconfined compression tests on specimens sampled from the same cement-treated ground. The quality estimated by the technique was consistent with the results of unconfined compression tests, indicating that the technique is a simple and useful means of inspecting the quality of cement-treated ground.
Performance of an embankment supported on soft soil reinforced by stone columns
Authors: Mohamedzein Yahia E.-A. , Al-Shibani Igbal Hassan
Published: July 2016

This paper presents a case study of a bridge approach embankment constructed on a soft soil reinforced by stone columns. The soft soil consisted of highly plastic clay with an undrained shear strength as low as 4 kPa. The thickness of the soft soil ranged from 2·5 to 8·5 m. The stone columns were installed through the soft soil by vibro-replacement technique. The stone columns were extended about 0·5 m into the underlying dense to very dense sand, sandstone or mudstone. The overall performance of the treated soil under the embankment load was evaluated using settlement plates. The field measurements were compared to the predictions of the analytical and finite-element methods. Most of the methods predicted settlements that are comparable to the measured values. Furthermore, the finite-element analysis shows that for deep deposits of soft soil, floating stone columns with a length/depth ratio of 0·5 can be as effective as the end bearing stone columns. Furthermore, the settlement reduction factor decreases with the increase in the area replacement ratio. Beyond an area replacement ratio of 0·4, the decrease in the settlement reduction factor is insignificant.
Considerations for ensuring the durability of chemically stabilised road materials
Authors: Paige-Green Philip
Published: July 2016

As the scarcity of good-quality materials for the construction of roads and the demand for recycling of existing pavement structures increases, the use of chemical stabilisation is becoming more frequent. However, it is essential to ensure that the long-term durability of the stabilised material is sufficient to provide the structural capacity required over the design life of the road. Experience gained in South Africa over the past 25 years has shown that many failures of stabilised materials are the result of a lack of understanding of fundamental processes related to materials and stabilisation, which can be overcome by better training and implementation of existing knowledge. Carbonation of stabilised materials is a particular problem that needs to be assessed. This paper discusses various problems, with proposed solutions based on the evidence of many years of laboratory and field investigations in an attempt to ensure the optimum durability of stabilised layers and to provide a source of material for a better understanding.
Low-temperature calcite precipitation in sand using CIPS
Authors: Palmén Anders , Price Graham , Axelsson Morgan , Larsson Stefan
Published: July 2016

The permeation grouting system CIPS (calcite in situ precipitation system) stabilises granular soil by hydrolysing the urea and causing calcite crystals to precipitate at the contact points of the grains. At low temperatures, the activity of urea hydrolysis is slow, causing concern that the CIPS system might not build sufficient strength in order to be an efficient soil stabilisation method. Most of the documented experience and research have been conducted in Australia; in order to examine the suitability of CIPS under Scandinavian climate conditions, where the operating temperature for the method needs to be adjusted to around 10°C, a laboratory study was conducted. The test cores were all treated and stabilised in a temperature-controlled room simulating Scandinavian ground conditions. After different lengths of curing time, some of the cemented samples were tested saturated for unconfined compressive strength (UCS); the other samples were allowed to dry at either 10 or 20°C before they were tested for UCS. The tests showed a rather obvious increase in strength especially after allowing the spent fluid to deplete, causing the samples to dry out; only a slight difference in UCS increase was recorded between the drying temperature of 10 and 20°C.
Strength indices of high-moisture soils using handheld gauges
Authors: Vahedifard Farshid , Howard Isaac L. , Badran Walaa H. , Carruth William D. , Hamlehdari Maysam , Jordan Brian D.
Published: July 2016

Large volumes of very high moisture content fine-grained soils (very high-moisture soils (VHMS)) are encountered annually. Stabilisation of these soils has been documented as a promising approach for disposal or reuse. Construction using stabilised fine-grained soils with high moisture contents is highly dependent on strength gain with time. This study evaluated the ability of handheld gauges to provide a rapid strength index in VHMS. The results obtained from pocket penetrometer, pocket geotester and pocket vane shear set were evaluated. Testing matrices included using three fine-grained soils and five types of Portland cement. Handheld gauges were used to measure a strength index for numerous cases, resulting in more than 2000 readings with each of the gauges. Approximately 300 unconfined compression tests were also conducted and the results were used to develop strength correlations to handheld gauge indices. The results showed that, in general, there was no considerable proximity difference between the pocket geotester and the pocket penetrometer, but there was a considerable difference relative to the pocket vane shear set. A comparison between the coefficients of variation showed the pocket geotester to be the most repeatable. It is noted that these devices only provide index values and additional tests are always recommended on field samples.
The swelling behaviour of lignosulfonate-treated expansive soil
Authors: Alazigha Dennis Pere , Indraratna Buddhima , Vinod Jayan S. , Ezeajugh Lambert Emeka
Published: July 2016

This paper presents results regarding the potential of lignosulfonate (LS) to control the swelling of expansive soil. One-dimensional swell tests were performed on untreated and LS-treated remoulded samples of Australian expansive soil from the state of Queensland. The test results indicated that LS has significant influence on the swelling behaviour of this expansive soil. The results were compared with those of identical cement-treated soil samples, and it was found that LS could be a economical and environmentally friendly alternative to traditional alkaline additives. In addition, the behaviour of LS-treated specimens during repeated freezing and thawing cycles was measured. The results indicated significant improvement in the percentage mass loss in LS-treated specimens compared with cement-treated specimens. The microstructural analysis of the untreated and the LS-treated samples showed soil surface area reduction in the treated specimens, which in turn reduced the affinity of the specimens towards moisture uptake, resulting in a reduction in the swell potential of the otherwise expansive soil. The use of LS as a novel non-traditional stabiliser for expansive soil appears to be a viable solution in view of the sustainable use of waste by-products and green construction.
Impact of managed realignment design on estuarine water levels
Authors: Pontee Nigel I.
Published: July 2016

Large realignment sites near the mouth of an estuary have the potential to raise water levels throughout the estuary. This increase is produced by the newly created intertidal area drawing additional water into the estuary on the flood tide. Although some of this additional water enters the realignment site, a proportion also bypasses the realignment site and continues upstream, thus increasing water levels in these areas of the estuary. The modelling results described in this paper suggest that an important determinant on estuary water levels is the rate at which the realignment site fills. Schemes that fill more slowly are predicted to have less impact than those that fill more rapidly, even if high water levels within the schemes are similar. For the schemes tested in this paper, the rate at which the site flooded appeared to depend less on breach dimensions and more on the width of the site that the flood waters had to cross in order to cause full inundation. It is proposed that those options with the shortest distances result in the flood tidal waters experiencing less frictional losses. These options showed a more rapid rise in water levels within the site, and produced a correspondingly larger increase in water levels within the estuary.
Sand erosion with a traversing circular jet
Authors: Weegenaar Robert A. , Keetels Geert H. , Winkelman Mark O. , van Rhee Cees
Published: July 2016

Trailing suction hopper dredgers (TSHDs) are the workhorses of the dredging industry. These ships trail a draghead over the seabed to excavate soil. It is now common for TSHDs to be equipped with water-jet assisted dragheads to enhance their production. These jets are vital for efficient dredging and are used to fluidise the soil. This reduces forces on the cutting teeth and makes the sand–water mixture more suitable for upward transport through the suction pipe. This research focuses on understanding the interaction of a horizontally moving, vertical jet with a (non-cohesive) sand bed. The aim is to predict the jet production, which is the mass flux of fluidised sand. Experiments have been executed at the Dredging Laboratory of the Delft University of Technology. The results were compared to an existing jet production formula. The formula states that the mass flux of fluidised soil is linearly dependent on the jet momentum flux. It is a simple and practical formula; however, it has not been validated thoroughly. More investigation was therefore needed. On average, the formula was shown to be in fairly good agreement with the experiments.
Wave loading on rock lighthouses
Authors: Raby Alison , Bullock Geoffrey N. , Banfi Davide , Rafiq Yaqub , Cali Federico
Published: July 2016

Historical and contemporary observations of wave-impact loading on rock lighthouses during storms are presented. With climate change potentially causing sea level rise and more energetic wave climates, the longevity of these heritage structures cannot be taken for granted. To obtain a better understanding of the wave–structure interaction, Plymouth University has been working with the General Lighthouse Authorities to develop monitoring and modelling techniques suitable for these isolated masonry structures. Details of the field campaign, in which 2978 impact events were recorded during the winter storms of 2013/2014, are presented together with an initial analysis that begins to shed light on the dynamic response of these iconic structures. The results indicate that the response can be sensitive to the type of wave impact and that the overall motion of the Eddystone tower was less than might have been expected. A finite-element model of the tower was able to reproduce accurately the frequencies of the first and third modes of vibration but, unlike the field data, failed to show response at a frequency near the second mode. Preliminary attempts to apply wave loads estimated on the basis of ISO 21650 show reasonable agreement between the model displacements and those measured.
Present-day use of an empirical wave prediction method
Authors: Lo Re Carlo , Cannarozzo Marcella , Ferreri Giovanni Battista
Published: July 2016

Knowledge of the offshore wave climate is key to the design of coastal engineering structures and to the study of shoreline evolution. To date, the available wave data have been limited both in time and space; even though there are several options for obtaining wave data calculated using complex numerical models at basin scale, design issues can in some cases be solved by means of simpler models. This paper shows whether, under certain conditions and in an enclosed basin, an old empirical model can provide results that are good enough to determine the design condition necessary for engineering purposes. The empirical model chosen to answer this question is called Sverdrup–Munk–Bretschneider modified (SMB-X) and was developed based on the indications of the Shore Protection Manual. The model was applied to an area off the northern coast of Sicily (Italy). The results were compared with measurements from a wave buoy. To evaluate whether the model is an efficient tool to calculate the ‘design wave’, a statistical analysis of extreme events is necessary. Such an analysis was performed on the measured wave parameters, on the wave parameters calculated by the empirical model and on those calculated by two spectral models that are as easy to use as the SMB-X.
Engineering of an island-style breakwater system for the Fort Pierce marina
Authors: Cox Jack C. , Czlapinski Richard E.
Published: July 2016

The push to create shore and harbour protection that is environmentally more compatible often puts the reality of the needs for resilience and strength at odds with the needs of nature. Softer protection schemes, such as floating wave attenuators and non-bottom-founded protection methods, are typically inadequate to resist the ravages of a storm, whereas the construction of solid ring breakwaters changes the texture of the shoreline and affects the biota. Out-of-the-box thinking was required to find an approach that could both emulate the natural environment and yet still be resilient enough to protect against hurricane events, promote ecology and offer safe and manageable navigation. The solution was found in building a protection system of artificial islands configured to create wave sheltering, oriented to reduce long-term sedimentation effects by controlling tidal flow patterns and executed to be a living island archipelago with both benthic and terrestrial habitat.
Spar concrete monolithic design for offshore wind turbines
Authors: Campos Alexis , Molins Climent , Gironella Xavier , Trubat Pau
Published: July 2016

Significant research efforts are now being directed at floating offshore wind turbines. The main challenge posed by floating wind turbines is the high construction and installation costs of the substructure, which make it too expensive for commercial exploitation in the current energy market. With the aim of achieving a cost-effective floating platform for offshore wind turbines, a new concept of a monolithic floating spar buoy is hereby presented. The monolithic concrete structure includes both the tower and the floater, built as a continuous single piece. This new concept offers a significant cost reduction during the construction phase and also while in operation, because the platform becomes almost free of maintenance during its lifetime. The main dimensions and the hydrostatic and hydrodynamic properties are presented, including a basic structural assessment of the platform to ensure its structural integrity. The construction and installation processes are presented, taking into account the special requirements of the monolithic design. Finally, a cost comparison between a steel and an equivalent concrete platform design has been performed, showing a material cost reduction larger than 60% in the case of the concrete design.
Non-linear analysis of quay wall combi-pile infill sheets
Authors: Ahmed Husham , Douglas Adrian
Published: July 2016

This paper describes an analysis of infill sheets of a combi-pile quay wall. Non-linear finite-element analysis of combi-pile infill sheets was required as the residual thickness of the selected infill sheet profile was thinner than the proscriptive requirements of the Eurocode base case and the geometric restrictions required wider infill sheets than permitted. The analysis enabled an assured design to be adopted. The variation of corrosion allowance down the pile was assessed in conjunction with the varying tidal lag behind the wall to determine the critical locations. The analysis required geometric and material non-linearities. The results of the analysis were compared with previous physical model testing. A simplified elastic analysis was validated for thin infill sheets under low water pressures.
Chloride penetration of RHA concrete under marine environment
Authors: Jayanti Dewi Sri , Mirza Jahangir , Jaya Ramadhansyah Putra , Bakar Badorul Hisham Abu , Hassan Norhidayah Abdul , Hainin Mohd Rosli
Published: July 2016

Chloride-ion penetration in rice husk ash (RHA)-blended cement in concrete that was exposed to a marine environment for 2 years was examined. RHA partially replaced Portland cement type I at 0, 10, 20, 30 and 40% levels based on the weight of the cement. Concrete samples sized 100 mm × 200 mm were cast and cured in water for 28 d, before being placed in the tidal zone of the Gulf of Malaysia. After being kept in the tidal zone for 3, 6, 9, 12, 18 and 24 months, the concrete cube samples were evaluated based on the depth of chloride ion and chloride penetration. Microstructural changes in the samples were also examined by scanning electron microscopy. The chloride ion and chloride penetration depth in Portland cement concrete was higher than that of RHA-blended cement concrete. It continued to decrease along with increasing levels of RHA replacement. Moreover, the use of 40% RHA in the cement resulted in better resistance to seawater when the concrete sample was exposed to the tidal zone for 2 years. The use of 10–40% RHA also effectively decreased the chloride penetration depth in the concrete from 16·8 to 11·3 mm.
The use and abuse of programmes in construction contracts
Authors: Kidd Andrew , Appelbe Stuart , Morgan Anthony
Published: July 2016

Many disputes arise on engineering and construction contracts due to the risks that are inherent in the realisation of complex projects in challenging environments. While contracts encourage collaboration between parties, the commercial consequences of managing risk and uncertainty can create tension. This paper reflects some of the authors’ experience of the use of programmes in international construction contracts. It identifies some of the issues that arise from integrating the rights and obligations set out in contract conditions with time, cost and risk management activities. It highlights the challenges that face project funders, contract administrators, project managers, designers, contractors and their suppliers in planning and reporting on the progress achieved in their project. This paper illustrates the tension between the commercial consequences of risk and transparency of contractor performance. It discusses how issues can arise that reduce the effectiveness of the programme as a collaborative management tool. It also proposes how some of these issues can be guarded against when establishing the contracting environment and in the subsequent administration of the contract.
Briefing: Taiwan high-speed railway and international contractors
Authors: Fleming Bernard
Published: July 2016

This briefing article describes the contract and management strategy adopted to encourage international contractors to participate in the US$16 billion Taiwan High Speed Rail Project, which opened for revenue service in January 2007. The paper concentrates on the civil works for the project, which consisted of 345 km of tunnels, elevated viaducts/bridges and embankment.
Sustainable procurement strategies for competitive advantage: an empirical study
Authors: Renukappa Suresh , Akintoye Akintola , Egbu Charles , Suresh Subashini
Published: July 2016

Procurement plays a key role in sustainability as policies and practices need to extend beyond organisations’ boundaries to incorporate their whole supply chains. There is, however, a paucity of empirical research on sustainable forms of procurement initiatives currently being implemented in the UK construction sector to improve competitiveness – which is the core driver of this paper. In order to achieve this aim, a mixed research methodological approach was adopted to collect and analyse data. The findings are based primarily on quantitative data obtained from 53 completed postal questionnaires and semi-structured interviews with 17 professionals from 12 UK construction organisations. As revealed by this study, sustainable procurement is becoming increasingly important in the UK construction sector. The paper concludes that the process of integrating sustainable procurement initiatives into existing business models is often a complex issue. Therefore, there is an urgent need to explore the drivers and impediments associated with the successful integration of sustainable procurement initiatives into existing construction business models. It is also suggested that there is a need for cross-sector collaboration to capture and share best and worst practices relating to sustainable procurement strategies.
Early contractor involvement in framework contracts
Authors: Laryea Samuel , Watermeyer Ron
Published: July 2016

Early contractor involvement (ECI) has been used for construction procurement in about 30 countries. The reasons for its adoption include collaboration, integration of design and construction, value for money and utilisation of market capacity. At least two models of ECI are reported in the literature. A different model of ECI has been used in framework contracts at Wits University in South Africa. The research aim was to analyse how this type of ECI works and its value to the success of projects. Data were collected through ten interviews, documentary analysis and observation of one ECI session. Through framework agreements, an opportunity is created to have ECI. Once concept designs and elemental cost estimates are prepared, the contractor is brought in to assist with value-engineering of the design and production drawings. ECI produced 12% cost savings in one project and 32% in another. Team integration and ECI are supported by framework agreements and NEC contracts. Although contractors receive no remuneration for the involvement in design development, they value the benefits of developing early cost models and production plans. Conditions for successful adoption are an intelligent client, a framework agreement, collaborative contracts, cost-based pricing strategies, the professional team’s flexibility and a committed contractor.
Line-of-balance against linear scheduling: critical comparison
Authors: Lucko Gunnar , Gattei Giovani
Published: July 2016

Among alternative scheduling techniques in construction management are linear and repetitive scheduling and line of balance (LOB). They are uniquely different from the dominant network-based technique because they have been developed for projects with repetitive units of work and crew operations. Notably, they feature quantitative measures of both work and time, which no network-based approach offers. However, a study of their origins – for example, the US Navy – reveals that their original use and capabilities deviate from current application, which is limited at best. Indeed, currently, the name-giving LOB is itself omitted. Therefore, this research has the goal to explore these scheduling techniques in detail. Its objectives are to delineate their modelling elements as described by original sources in a structured manner, to compare them in detail and identify any changes over time and to comment on implications for practical use and extract unsolved research questions. Its methodology follows a comparative research approach. Differences are found in how productivity and cyclic crew deployment are expressed, besides the glaring omission of the LOB itself in the construction use of this method. It is found that, historically, LOB was intended for manufacturing, but when introduced to construction, important characteristics of the production plan and progress chart became forgotten. In parallel, linear scheduling was developed for construction, whose similarities to LOB may have added confusion. Clarifying the complete methods by explicitly outlining their analytical capabilities will improve understanding to allow project managers to benefit from these powerful tools. It also enables future research to model LOB with singularity functions to yield a unified formulation of these alternative scheduling techniques.
The concept of partnering in public–private partnership projects in the United Arab Emirates
Authors: Khalifa Mohamed , Farrell Peter , Emam Hassan
Published: July 2016

The construction industry is known for poor performance and adversarial relations between its participants; traditional procurement processes based on competitive tendering are often blamed for this deficiency. Partnering was introduced in the literature as an approach that encourages co-operation across contractual boundaries. After two decades, it has arguably not been as successful as was hoped. This paper investigates the perception of contractors participating in public–private partnership (PPP) projects in the United Arab Emirates to enhance partnering implementation processes. The study focuses on project-level interactions on PPP projects. Two projects were examined in the field research as case studies through qualitative interviews with a total of five key personnel, in addition to collecting relevant data from contractors’ archives. The research identified agreements on some of the claimed advantages of partnering such as improved performance, optimum use of resources and improved client satisfaction. However, there was no consensus regarding many features of partnering, including co-operation, improving relations and developing trust between parties. This was attributable to the inadequate experience among project teams, the lack of management leadership and the gap between management and project teams’ perceptions of partnering. The research concluded that leadership, training and clear definition of responsibilities between the partners are among the main success factors for partnering projects.
A contract manager abroad: cultural awareness in Asia
Authors: Webb Eric
Published: July 2016

Western contract managers often enter the Asian construction sector with personal, as well as corporate ways of working that will almost certainly not be a perfect fit with both the new environment within which they have to perform and the dispersed multicultural contractual teams within which interaction is invariably necessary on large complex projects. The management style expected and required in Asia is unique and, for many, appears to be unstructured, unsystemised and autocratic, with varying strains of Chinese-based ethics and beliefs, including networking, trust, face and avoidance of confrontation heavily influencing management practices. To avoid unnecessary problems, managers need to overcome not only the obvious language difficulties but also differing corporate cultures, work methods, national cultures and beliefs. These problems can be best overcome by adopting a holistic approach, collective work style, understanding the importance of hard and soft management, and by accepting that neither the Western way nor the Eastern way is the only way to manage.
Briefing: Statutory adjudication for construction disputes: an overview
Authors: Chan Adrian
Published: July 2016

Following the success of the introduction of security of payment legislation in the United Kingdom, there has been rapid growth globally in the enactment of similar legislation to address the vexed issues of late payment and cash-flow in the construction industry. This article provides an overview of the intended purpose of security of payment legislation and compares the differences between jurisdictions. Particular attention is drawn to the ‘Statutory Adjudication’ regime, and its attempts to preserve cash-flow during a project by resolving payment disputes in an expeditious and provisional manner.
Precast workflow productivity measurement through BIM adoption
Authors: Nath Tushar , Attarzadeh Meghdad , Tiong Robert L. K.
Published: July 2016

Building information modelling (BIM) is acknowledged globally as a key computer-aided technology that expedites construction productivity enhancements. Consequently, the utilisation of BIM has been gaining precedence in Singapore’s construction industry during the past few years, aiding enhanced project management. Productivity improvement has been a concern for the construction industry in Singapore in the last decade, and the method of measuring productivity improvement is one of the major issues. This study adopts a quantitative research and development approach to determine the impact of BIM on the productivity of Singapore’s precast industry. On the basis of the observations of the authors on the workflows followed by three precast firms in Singapore, this study aims to propose and apply a fuzzy mapping technique to measure productivity improvement; furthermore, it also identifies the constrictions in the present workflow and proposed an improved workflow to address the prevalent constraints to facilitate the transition of the precast firms towards enhanced productivity. In this paper, the productivity gains obtained through the change in the workflow for specific activities were identified and recorded, and the critical activities deviating towards a lower percentage in terms of productivity were deemed essential to be diligently taken into account by the precast firms.
Briefing: A change for Construction Law Quarterly
Authors: Ramster Ben
Published: July 2016

In 2016, ICE Construction Law Quarterly begins publishing as part of the journal Proceedings of the Institution of Civil Engineers – Management, Procurement and Law. This change is designed to increase the amount of practice content carried annually by Management, Procurement and Law and to take ICE Construction Law Quarterly content to a wider international audience.
Estimating design wave for offshore structures in Italian waters
Authors: Barbaro Giuseppe
Published: July 2016

This paper describes a methodology for estimating the design wave parameters for offshore structures. For the estimation of the design wave height the concept of an equivalent triangular storm is discussed. It is shown how it overcomes the limitations of previous methodologies. For the estimation of the wave period a quasi-deterministic theory is applied. A description is given of the simple method proposed, which requires only the estimation of the significant wave height of the sea state in which the highest wave in the return period of the design wave will occur with the highest probability. Final discussions address examples of the estimation of design wave data to determine the size of offshore structures to be built along the coasts of Italy, the Pacific and Atlantic Oceans and Gulf of Alaska, using wave data gathered from instruments managed by the Environment and Territory Agency and the National Data Buoy Centre.
Collaborative governance in Greek infrastructure projects
Authors: Ojiako Udechukwu , Papadopoulos Thanos , Stamati Teta , Anagnostopoulos Dimosthenis , Marshall Alasdair
Published: July 2016

This study examines the key elements that underlie collaborative forms of governance in infrastructure project delivery. Data are obtained from interviews conducted with senior managers involved in the delivery of collaborative projects in Greece. The findings suggest that issues concerning inequality between partners, ownership of the delivery through collaborative governance and the time needed to take decisions and solve problems may hinder collaboration. The findings contribute to extant literature by showing that the challenges of adopting collaborative governance practices in Greece’s transitional economy may be related to under-developed systems that are not only unable to support the full exploitation of the practice, but also fail adequately to leverage emerging innovation. In terms of practical implications, the study contributes to an understanding of how stakeholders involved in public–private partnership projects view collaborative governance in project delivery, along with the conditions and difficulties that are present, and potential outcomes governance.
Calories and steps! How many days of walking/hiking in the Himalayas does ONE Christmas lunch translate to?
Authors: Pillay J D
Published: July 2016

Background. The festive season is a time when people are at risk of overeating and weight gain. An active break during this time can help maintain energy balance. Objectives. To determine steps taken during a walk/hike to Everest Base Camp and back and compare estimated activityrelated energy expenditure to a typical Christmas lunch. Methods. Five adults (39-70 years) completed an 11-day walk/hike. Pedometer-measured steps were recorded at two cadences: ‘aerobic’ (>100 steps/minute for 10 consecutive minutes) or ‘slower’ steps. Activity-related energy expenditure was estimated using generic values for walking uphill/downhill at each cadence. Energy intake of a typical Christmas lunch was estimated. Results. Participants accumulated a total of 143 770 steps, or 13 070 (SD 8 272) steps/day, 20% of which were ‘aerobic’. Total walk-related energy expenditure was estimated at 22 816  kcals, or 1 901 (SD 580) kcals/day. Conclusion. Estimated energy intake in one Christmas lunch equates to 1.7 days of walking/hiking. Keywords. Energy intake, physical activity, energy expenditure, pedometer
Gluteus medius kinesio-taping: the effect on torso-pelvic separation, ball flight distance and accuracy during the golf swing
Authors: Pearce B
Published: July 2016

Background. The kinesio-taping method, which is becoming increasingly popular, may provide support and stability to joints and muscles without inhibiting range of motion. Objective. The aim of the study was to determine the effect of kinesio-taping of the gluteus medius muscle on x-factor (torsopelvic separation), ball flight distance and accuracy (smash factor ratio). A specific aim was to determine whether a correlation exists between hip abduction strength and x-factor, ball distance and accuracy. Methods. This study is a one group pretest-posttest quasiexperimental design which took place at a golf facility. Twentynine amateur golfers with handicap of scratch ±2, who were between the ages of 18- and 25-years, participated in this study. Biomechanical outcomes were recorded with and without kinesio-tape applied on the gluteus medius muscle of the trail leg. Biomechanical golf swing analysis with the iClub™ Body Motion System determined the x-factor at the top of the backswing. Ball flight distance and accuracy were measured with FlightScope® and dominant hip abduction strength was measured with the MicroFET Hand-held Dynamometer. Results. Kinesio-tape is effective in improving the relative hip abduction strength (p<0.001), although the effect size was small (Cohen’s d=0.24). With regard to the biomechanical outcome measures, namely x-factor (p=0.28), ball flight distance (p=0.53) and accuracy (p=0.1), there was no significant improvement. Conclusion: Even though the relative hip abduction strength was improved, there was no effect on golf swing biomechanics. This can be explained due to the fact that x-factor, ball flight distance and accuracy are dependent on a combination of body movements to produce the golf swing. Keywords. Golf, X-factor, pelvic stability, taping