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Australian South Sea Islanders, the descendants of the Melanesians from (primarily) Vanuatu and Solomon Islands who were 'blackbirded' to Queensland and New South Wales (1847-1904) for their labour, have, through music and dance practices, come to identify as part of a global black 'transnation'. Studies of the 'Black Atlantic' point both to the transnational character of slavery and the importance of music as a medium of resistance. This article proposes that Australian South Sea Islanders' musical cultures might usefully be understood in terms of a parallel concept, the 'Black Pacific', in relation to which the Pacific's colonised and decolonised peoples have developed their own expressions of black pride and performed resistance. It argues that a more nuanced appreciation of Australian South Sea Islander performance culture as part of the Black Pacific will allow all Australians to better understand some of the vitally important yet obfuscated consequences of Australia's blackbirding past.

This chapter gives an overview of recent developments in the Monte Carlo-based modeling of the interaction of ionizing radiation with biologically relevant systems. Several track structure codes, such as Geant4 (GEometry ANd Tracking 4), Geant4-DNA, and LEPTS (Low-Energy Particle Track Simulation), are described. Main features, areas of application and current limitations of each tool are discussed. A special attention is focused on the energy range covered by primary and secondary charged particles and on the type of interactions included in the simulation. A recent development of LEPTS is presented, aimed at the simulation of full slowing-down of protons in water together with all molecular processes involving secondary particles. The utilized approach allows one to study radiation effects on the nanoscale in terms of the number and the type of induced molecular processes.

We present interaction probability data of low-energy secondary electrons and positrons produced due to the proton impact. The probability distribution functions serve as input data for the Low Energy Particle Track Simulation (LEPTS) approach which allows one to include the effect of low-energy species in medical applications of radiation and in ion-beam cancer therapy, in particular.

We present interaction probability data of low-energy secondary electrons and positrons produced due to the proton impact. The probability distribution functions serve as input data for the Low Energy Particle Track Simulation (LEPTS) approach which allows one to include the effect of low-energy species in medical applications of radiation and in ion-beam cancer therapy, in particular.

We present interaction probability data of low-energy secondary electrons and positrons produced due to the proton impact. The probability distribution functions serve as input data for the Low Energy Particle Track Simulation (LEPTS) approach which allows one to include the effect of low-energy species in medical applications of radiation and in ion-beam cancer therapy, in particular.

We present interaction probability data of low-energy secondary electrons and positrons produced due to the proton impact. The probability distribution functions serve as input data for the Low Energy Particle Track Simulation (LEPTS) approach which allows one to include the effect of low-energy species in medical applications of radiation and in ion-beam cancer therapy, in particular.

Ballast fouling is understood as major cause of track deterioration in many countries over the world. It decreases the drainage and load bearing capacity of the ballast layer. A series of large scale hydraulic conductivity tests were conducted with different proportions of fouling to access the drainage capacity of the track. A numerical analysis was conducted using SEEP/W to quantify the drainage capacity of ballast under different degrees of fouling. Subsequently, track drainage classification in relation to the degree of fouling, which is a very useful tool for practical engineers, is presented in this paper. The analysis showed that both the location and extent of fouling played an important role when assessing the overall drainage capacity of track. In order to establish the relationship between the extent of fouling and the associated strength-deformation properties, a series of large scale monotonic triaxial tests were carried out for different levels of fouling for three different confining pressures. Based on the laboratory findings, a novel empirical relationship between the peak deviator stress and VCI has been proposed to assist the practitioner in their preliminary track condition assessment. By considering drainage and strength aspects, a critical level of fouling to assist in track maintenance planning has been considered.

Ballast fouling is understood as major cause of track deterioration in many countries over the world. It decreases the drainage and load bearing capacity of the ballast layer. A series of large scale hydraulic conductivity tests were conducted with different proportions of fouling to access the drainage capacity of the track. A numerical analysis was conducted using SEEP/W to quantify the drainage capacity of ballast under different degrees of fouling. Subsequently, track drainage classification in relation to the degree of fouling, which is a very useful tool for practical engineers, is presented in this paper. The analysis showed that both the location and extent of fouling played an important role when assessing the overall drainage capacity of track. In order to establish the relationship between the extent of fouling and the associated strength-deformation properties, a series of large scale monotonic triaxial tests were carried out for different levels of fouling for three different confining pressures. Based on the laboratory findings, a novel empirical relationship between the peak deviator stress and VCI has been proposed to assist the practitioner in their preliminary track condition assessment. By considering drainage and strength aspects, a critical level of fouling to assist in track maintenance planning has been considered.

Ballast fouling is understood as major cause of track deterioration in many countries over the world. It decreases the drainage and load bearing capacity of the ballast layer. A series of large scale hydraulic conductivity tests were conducted with different proportions of fouling to access the drainage capacity of the track. A numerical analysis was conducted using SEEP/W to quantify the drainage capacity of ballast under different degrees of fouling. Subsequently, track drainage classification in relation to the degree of fouling, which is a very useful tool for practical engineers, is presented in this paper. The analysis showed that both the location and extent of fouling played an important role when assessing the overall drainage capacity of track. In order to establish the relationship between the extent of fouling and the associated strength-deformation properties, a series of large scale monotonic triaxial tests were carried out for different levels of fouling for three different confining pressures. Based on the laboratory findings, a novel empirical relationship between the peak deviator stress and VCI has been proposed to assist the practitioner in their preliminary track condition assessment. By considering drainage and strength aspects, a critical level of fouling to assist in track maintenance planning has been considered.

Ballast fouling is understood as major cause of track deterioration in many countries over the world. It decreases the drainage and load bearing capacity of the ballast layer. A series of large scale hydraulic conductivity tests were conducted with different proportions of fouling to access the drainage capacity of the track. A numerical analysis was conducted using SEEP/W to quantify the drainage capacity of ballast under different degrees of fouling. Subsequently, track drainage classification in relation to the degree of fouling, which is a very useful tool for practical engineers, is presented in this paper. The analysis showed that both the location and extent of fouling played an important role when assessing the overall drainage capacity of track. In order to establish the relationship between the extent of fouling and the associated strength-deformation properties, a series of large scale monotonic triaxial tests were carried out for different levels of fouling for three different confining pressures. Based on the laboratory findings, a novel empirical relationship between the peak deviator stress and VCI has been proposed to assist the practitioner in their preliminary track condition assessment. By considering drainage and strength aspects, a critical level of fouling to assist in track maintenance planning has been considered.

This colloquium describes an approach to incorporate into radiation damage models the effect of low and intermediate energy (0-100 eV) electrons and positrons, slowing down in biologically relevant materials (water and representative biomolecules). The core of the modelling procedure is a C++ computing programme named "Low Energy Particle Track Simulation (LEPTS)", which is compatible with available general purpose Monte Carlo packages. Input parameters are carefully selected from theoretical and experimental cross section data and energy loss distribution functions. Data sources used for this purpose are reviewed showing examples of electron and positron cross section and energy loss data for interactions with different media of increasing complexity: atoms, molecules, clusters and condense matter. Finally, we show how such a model can be used to develop an effective dosimetric tool at the molecular level (i.e. nanodosimetry). Recent experimental developments to study the fragmentation induced in biologically material by charge transfer from neutrals and negative ions are also included.

Rail tracks are conventionally built on compacted ballast and structural fill embankments overlying the natural subsoil. Ballast plays an important role in providing track stiffness to support heavy traffic loads, and providing rapid drainage. However, ballast deforms and degrades progressively under the heavy cyclic loading of passenger and freight trains, which may lead to a loss of track geometry, and require costly regular maintenance. In particular, track construction requires appropriate stabilization techniques for ballast, the extent of which depends also on the type of subgrade. Comprehensive field trials were carried out on two rail lines in Bulli and recently in Singleton, New South Wales, Australia. In these studies, several track sections were reinforced with different types of geosynthetics placed beneath the ballast embankment. Both fresh and recycled ballast was examined for varying subgrade conditions. Recoverable and irrecoverable deformations of the substructure were routinely monitored. It was found that geogrids and geocomposites can decrease the vertical strains of the ballast layer, resulting in reduced maintenance costs. This paper describes the comprehensive field instrumentation, construction procedures, and field performance evaluation of these full-scale geosynthetic- stabilized ballast embankments in Bulli and Singleton.

In Australia, railways offer the most prominent transportation mode in terms of traffic tonnage serving the needs of bulk freight and passenger movement. Ballast is an essential constituent of conventional rail infrastructure governing track stability and performance. However in recent times higher traffic induced stresses due to dramatically increased tgrain speeds and heavier axle loads have caused excessive plastic deformations and degradation of ballast. This seriously hampers safety and efficiency of express tracks, for instance, enforcing speed restrictions and effecting more frequent track maintenance. Installing layers of synthetic materials such geogrids and rubber pads (shock mats) in rail tracks can significantly reduce ballast degradation. Field trials were conducted on rail track sections in the towns of Bulli (near Wollongong city) and Singleton (near Newcastle) to measure track deformations associated with cyclic stresses and impact loads. This paper describes the results of large-scale laboratory testing as well as the observations from full-scale instrumented field trials characterising the behaviour of rail ballast improved by shock mats and synthetic grids.

Rail tracks are conventionally built on compacted ballast and structural fill embankments overlying the natural subsoil. Ballast plays an important role in providing track stiffness to support heavy traffic loads, and providing rapid drainage. However, ballast deforms and degrades progressively under the heavy cyclic loading of passenger and freight trains, which may lead to a loss of track geometry, and require costly regular maintenance. In particular, track construction requires appropriate stabilization techniques for ballast, the extent of which depends also on the type of subgrade. Comprehensive field trials were carried out on two rail lines in Bulli and recently in Singleton, New South Wales, Australia. In these studies, several track sections were reinforced with different types of geosynthetics placed beneath the ballast embankment. Both fresh and recycled ballast was examined for varying subgrade conditions. Recoverable and irrecoverable deformations of the substructure were routinely monitored. It was found that geogrids and geocomposites can decrease the vertical strains of the ballast layer, resulting in reduced maintenance costs. This paper describes the comprehensive field instrumentation, construction procedures, and field performance evaluation of these full-scale geosynthetic- stabilized ballast embankments in Bulli and Singleton.

In Australia, railways offer the most prominent transportation mode in terms of traffic tonnage serving the needs of bulk freight and passenger movement. Ballast is an essential constituent of conventional rail infrastructure governing track stability and performance. However in recent times higher traffic induced stresses due to dramatically increased tgrain speeds and heavier axle loads have caused excessive plastic deformations and degradation of ballast. This seriously hampers safety and efficiency of express tracks, for instance, enforcing speed restrictions and effecting more frequent track maintenance. Installing layers of synthetic materials such geogrids and rubber pads (shock mats) in rail tracks can significantly reduce ballast degradation. Field trials were conducted on rail track sections in the towns of Bulli (near Wollongong city) and Singleton (near Newcastle) to measure track deformations associated with cyclic stresses and impact loads. This paper describes the results of large-scale laboratory testing as well as the observations from full-scale instrumented field trials characterising the behaviour of rail ballast improved by shock mats and synthetic grids.

Rail tracks are conventionally built on compacted ballast and structural fill embankments overlying the natural subsoil. Ballast plays an important role in providing track stiffness to support heavy traffic loads, and providing rapid drainage. However, ballast deforms and degrades progressively under the heavy cyclic loading of passenger and freight trains, which may lead to a loss of track geometry, and require costly regular maintenance. In particular, track construction requires appropriate stabilization techniques for ballast, the extent of which depends also on the type of subgrade. Comprehensive field trials were carried out on two rail lines in Bulli and recently in Singleton, New South Wales, Australia. In these studies, several track sections were reinforced with different types of geosynthetics placed beneath the ballast embankment. Both fresh and recycled ballast was examined for varying subgrade conditions. Recoverable and irrecoverable deformations of the substructure were routinely monitored. It was found that geogrids and geocomposites can decrease the vertical strains of the ballast layer, resulting in reduced maintenance costs. This paper describes the comprehensive field instrumentation, construction procedures, and field performance evaluation of these full-scale geosynthetic- stabilized ballast embankments in Bulli and Singleton.

In Australia, railways offer the most prominent transportation mode in terms of traffic tonnage serving the needs of bulk freight and passenger movement. Ballast is an essential constituent of conventional rail infrastructure governing track stability and performance. However in recent times higher traffic induced stresses due to dramatically increased tgrain speeds and heavier axle loads have caused excessive plastic deformations and degradation of ballast. This seriously hampers safety and efficiency of express tracks, for instance, enforcing speed restrictions and effecting more frequent track maintenance. Installing layers of synthetic materials such geogrids and rubber pads (shock mats) in rail tracks can significantly reduce ballast degradation. Field trials were conducted on rail track sections in the towns of Bulli (near Wollongong city) and Singleton (near Newcastle) to measure track deformations associated with cyclic stresses and impact loads. This paper describes the results of large-scale laboratory testing as well as the observations from full-scale instrumented field trials characterising the behaviour of rail ballast improved by shock mats and synthetic grids.

Make seven walks up from my home to places where there are illegally dumped cars in the escarpment bush. On each occasion, cut out a square section of a car with an angle grinder and carry the piece home. This scheme provides the basis for a work that responds to the impure complexity of the local illawarra environment. The aim is not only to intervene, in a small way, within sites of vandalism, but also to descend down into the space where car and forest meet. The work takes shape partly as a set of sculptural samples and absences, and partly as field of action - walking, cutting, image-making and writing.

To reflect on the Illawarra culture of dumping rubbish in the local escarpment bush. To reflect on the limited capacity of art to effectively intervene in the culture of dumping – perhaps only through doubling and complicity is anything possible? To remediate Land Art traditions by intervening not in nature itself, but in a layer of impure addition and by deliberately avoiding the grand scale of 60’s US Land Art. The work also plays homage to the cutting works of Gordon Matta-Clark

This colloquium describes an approach to incorporate into radiation damage models the effect of low and intermediate energy (0-100 eV) electrons and positrons, slowing down in biologically relevant materials (water and representative biomolecules). The core of the modelling procedure is a C++ computing programme named "Low Energy Particle Track Simulation (LEPTS)", which is compatible with available general purpose Monte Carlo packages. Input parameters are carefully selected from theoretical and experimental cross section data and energy loss distribution functions. Data sources used for this purpose are reviewed showing examples of electron and positron cross section and energy loss data for interactions with different media of increasing complexity: atoms, molecules, clusters and condense matter. Finally, we show how such a model can be used to develop an effective dosimetric tool at the molecular level (i.e. nanodosimetry). Recent experimental developments to study the fragmentation induced in biologically material by charge transfer from neutrals and negative ions are also included.

Make seven walks up from my home to places where there are illegally dumped cars in the escarpment bush. On each occasion, cut out a square section of a car with an angle grinder and carry the piece home. This scheme provides the basis for a work that responds to the impure complexity of the local illawarra environment. The aim is not only to intervene, in a small way, within sites of vandalism, but also to descend down into the space where car and forest meet. The work takes shape partly as a set of sculptural samples and absences, and partly as field of action - walking, cutting, image-making and writing.

Rail tracks are conventionally built on compacted ballast and structural fill embankments overlying the natural subsoil. Ballast plays an important role in providing track stiffness to support heavy traffic loads, and providing rapid drainage. However, ballast deforms and degrades progressively under the heavy cyclic loading of passenger and freight trains, which may lead to a loss of track geometry, and require costly regular maintenance. In particular, track construction requires appropriate stabilization techniques for ballast, the extent of which depends also on the type of subgrade. Comprehensive field trials were carried out on two rail lines in Bulli and recently in Singleton, New South Wales, Australia. In these studies, several track sections were reinforced with different types of geosynthetics placed beneath the ballast embankment. Both fresh and recycled ballast was examined for varying subgrade conditions. Recoverable and irrecoverable deformations of the substructure were routinely monitored. It was found that geogrids and geocomposites can decrease the vertical strains of the ballast layer, resulting in reduced maintenance costs. This paper describes the comprehensive field instrumentation, construction procedures, and field performance evaluation of these full-scale geosynthetic- stabilized ballast embankments in Bulli and Singleton.

To reflect on the Illawarra culture of dumping rubbish in the local escarpment bush. To reflect on the limited capacity of art to effectively intervene in the culture of dumping – perhaps only through doubling and complicity is anything possible? To remediate Land Art traditions by intervening not in nature itself, but in a layer of impure addition and by deliberately avoiding the grand scale of 60’s US Land Art. The work also plays homage to the cutting works of Gordon Matta-Clark

In Australia, railways offer the most prominent transportation mode in terms of traffic tonnage serving the needs of bulk freight and passenger movement. Ballast is an essential constituent of conventional rail infrastructure governing track stability and performance. However in recent times higher traffic induced stresses due to dramatically increased tgrain speeds and heavier axle loads have caused excessive plastic deformations and degradation of ballast. This seriously hampers safety and efficiency of express tracks, for instance, enforcing speed restrictions and effecting more frequent track maintenance. Installing layers of synthetic materials such geogrids and rubber pads (shock mats) in rail tracks can significantly reduce ballast degradation. Field trials were conducted on rail track sections in the towns of Bulli (near Wollongong city) and Singleton (near Newcastle) to measure track deformations associated with cyclic stresses and impact loads. This paper describes the results of large-scale laboratory testing as well as the observations from full-scale instrumented field trials characterising the behaviour of rail ballast improved by shock mats and synthetic grids.

This chapter contains a laboratory assessment of the role of geosynthetics in the performance of railway ballast. The main objectives of this testing were to examine the actual potential of selected geosynthetic products for ballast stabilisation. A series of cyclic drained tests were carried out using a large scale prismoidal triaxial apparatus that was designed and built at the University of Wollongong, and is the most innovative cyclic process simulation testing equipment available in the world today. The effects of different types of geosynthetics, including bi-axial geogrid, non-woven geotextile and geocomposite (a combination of bi-axial geogrid and non-woven geotextile) have been evaluated as single layer and dual layer arrangements. The test findings revealed that bi-axial geogrid with aperture size of 40  40 mm and with minimum bi-directional strength that complies with the University of Wollongong recommendations, would be a suitable grid reinforcement to be placed under the ballast layer for track stabilisation. This particular non-woven geotextile offered an optimum separation function between the ballast and capping layers and maintained a higher resiliency during cyclic loading. Among the three types of geosynthetics tested, the use of geocomposite resulted in the least strain and particle breakage. The dual layer configuration reduced deformation and degradation better than the single layer configuration.

The goal of this work was to investigate the agreement of physical parameters related to the particle track structure on the nanometer scale, obtained by means of a detailed track structure simulation (PTra) as well as by a rapid analytical approach. Parameters describing the tracks of secondary electrons produced by 0.3 MeV/u C6+-ions were of particular interest as those particles are densely ionizing. For this purpose, the target volume in form of a nanometric water cylinder was positioned at different radial distances from the ion trajectory and track structure parameters were determined as function of the radial distance. While the fluence of electrons through the target surface and the mean ionization cluster size obtained by both approaches were in good agreement, the probabilities of specific cluster sizes (one, two and three) turned out to be rather different in the two approaches.

In Australia, quicker and more cost effective commuter and freight transports are essential to cater for the needs of travel demand and supply chains in the mining and agriculture sectors. Such development in coastal areas would necessitate the use of ground improvement techniques in response to environmental legislation and requirements for improved performance and sustainability. In coastal Australia the high cost of track maintenance is the main issue due to poor drainage of soft coastal soils, ballast degradation, fouling (e.g. coal and subgrade soil), differential settlement of track, pumping of subgrade soils and track misalignment due to excessive lateral movements. Hundreds of millions of dollars are spent each year on the construction and maintenance of rail tracks and the existing technical specifications, standards and design are often unable to address these problems. With increased train speeds, the capacity of the track is often inadequate unless more resilient tracks are designed to withstand the substantially increased vibration and cyclic and impact loads. The optimum use of maintenance funds is a challenging task due to the absence of comprehensive methods to predict track longevity even on terrain where the properties of the soils are well established. Until today, the vast majority of Australian track designs have considered ballast and structural fill as elastic granular media, and thus the designers have adopted predominantly empirical methods where true cyclic loading patterns and the onset of plasticity and degradation of track materials are ignored. In many European countries and some parts of Southeast Asia, especially among high speed rail networks, track vibrations are serious concerns. The mechanisms of ballast degradation and deformation, the need for effective track confinement, understanding the interface behaviour and the imperative need for flood protection, time dependent drainage and filtration properties of track materials requir

In Australia, quicker and more cost effective commuter and freight transports are essential to cater for the needs of travel demand and supply chains in the mining and agriculture sectors. Such development in coastal areas would necessitate the use of ground improvement techniques in response to environmental legislation and requirements for improved performance and sustainability. In coastal Australia the high cost of track maintenance is the main issue due to poor drainage of soft coastal soils, ballast degradation, fouling (e.g. coal and subgrade soil), differential settlement of track, pumping of subgrade soils and track misalignment due to excessive lateral movements. Hundreds of millions of dollars are spent each year on the construction and maintenance of rail tracks and the existing technical specifications, standards and design are often unable to address these problems. With increased train speeds, the capacity of the track is often inadequate unless more resilient tracks are designed to withstand the substantially increased vibration and cyclic and impact loads. The optimum use of maintenance funds is a challenging task due to the absence of comprehensive methods to predict track longevity even on terrain where the properties of the soils are well established. Until today, the vast majority of Australian track designs have considered ballast and structural fill as elastic granular media, and thus the designers have adopted predominantly empirical methods where true cyclic loading patterns and the onset of plasticity and degradation of track materials are ignored. In many European countries and some parts of Southeast Asia, especially among high speed rail networks, track vibrations are serious concerns. The mechanisms of ballast degradation and deformation, the need for effective track confinement, understanding the interface behaviour and the imperative need for flood protection, time dependent drainage and filtration properties of track materials requir

The goal of this work was to investigate the agreement of physical parameters related to the particle track structure on the nanometer scale, obtained by means of a detailed track structure simulation (PTra) as well as by a rapid analytical approach. Parameters describing the tracks of secondary electrons produced by 0.3 MeV/u C6+-ions were of particular interest as those particles are densely ionizing. For this purpose, the target volume in form of a nanometric water cylinder was positioned at different radial distances from the ion trajectory and track structure parameters were determined as function of the radial distance. While the fluence of electrons through the target surface and the mean ionization cluster size obtained by both approaches were in good agreement, the probabilities of specific cluster sizes (one, two and three) turned out to be rather different in the two approaches.

In Australia, quicker and more cost effective commuter and freight transports are essential to cater for the needs of travel demand and supply chains in the mining and agriculture sectors. Such development in coastal areas would necessitate the use of ground improvement techniques in response to environmental legislation and requirements for improved performance and sustainability. In coastal Australia the high cost of track maintenance is the main issue due to poor drainage of soft coastal soils, ballast degradation, fouling (e.g. coal and subgrade soil), differential settlement of track, pumping of subgrade soils and track misalignment due to excessive lateral movements. Hundreds of millions of dollars are spent each year on the construction and maintenance of rail tracks and the existing technical specifications, standards and design are often unable to address these problems. With increased train speeds, the capacity of the track is often inadequate unless more resilient tracks are designed to withstand the substantially increased vibration and cyclic and impact loads. The optimum use of maintenance funds is a challenging task due to the absence of comprehensive methods to predict track longevity even on terrain where the properties of the soils are well established. Until today, the vast majority of Australian track designs have considered ballast and structural fill as elastic granular media, and thus the designers have adopted predominantly empirical methods where true cyclic loading patterns and the onset of plasticity and degradation of track materials are ignored. In many European countries and some parts of Southeast Asia, especially among high speed rail networks, track vibrations are serious concerns. The mechanisms of ballast degradation and deformation, the need for effective track confinement, understanding the interface behaviour and the imperative need for flood protection, time dependent drainage and filtration properties of track materials requir

Two printing methods, extrusion and inkjet, are used to deposit tracks of PEDOT/PSS conducting polymer onto biopolymer films with a view to prepare implantable tissue mimics containing electronic devices. Extruded tracks offer lower printing resolution, but better electrical characteristics compared to inkjet printed tracks. The biopolymer–ink interaction results in narrower printed tracks compared to those on glass. This affects the final conductivity, which is lower for printed tracks on biopolymer than for lines printed on glass, due to the part of the track lying below the surface. Extrusion printing is used to embed tracks into a biopolymer matrix, resulting in significant improvement in electrical characteristics. The electrical conductivity of embedded tracks (17 S cm1) is an order of magnitude higher than for track deposition on the surface of biopolymer film and 3 times higher than for tracks on glass.

Two printing methods, extrusion and inkjet, are used to deposit tracks of PEDOT/PSS conducting polymer onto biopolymer films with a view to prepare implantable tissue mimics containing electronic devices. Extruded tracks offer lower printing resolution, but better electrical characteristics compared to inkjet printed tracks. The biopolymer–ink interaction results in narrower printed tracks compared to those on glass. This affects the final conductivity, which is lower for printed tracks on biopolymer than for lines printed on glass, due to the part of the track lying below the surface. Extrusion printing is used to embed tracks into a biopolymer matrix, resulting in significant improvement in electrical characteristics. The electrical conductivity of embedded tracks (17 S cm1) is an order of magnitude higher than for track deposition on the surface of biopolymer film and 3 times higher than for tracks on glass.

Two printing methods, extrusion and inkjet, are used to deposit tracks of PEDOT/PSS conducting polymer onto biopolymer films with a view to prepare implantable tissue mimics containing electronic devices. Extruded tracks offer lower printing resolution, but better electrical characteristics compared to inkjet printed tracks. The biopolymer–ink interaction results in narrower printed tracks compared to those on glass. This affects the final conductivity, which is lower for printed tracks on biopolymer than for lines printed on glass, due to the part of the track lying below the surface. Extrusion printing is used to embed tracks into a biopolymer matrix, resulting in significant improvement in electrical characteristics. The electrical conductivity of embedded tracks (17 S cm1) is an order of magnitude higher than for track deposition on the surface of biopolymer film and 3 times higher than for tracks on glass.

Two printing methods, extrusion and inkjet, are used to deposit tracks of PEDOT/PSS conducting polymer onto biopolymer films with a view to prepare implantable tissue mimics containing electronic devices. Extruded tracks offer lower printing resolution, but better electrical characteristics compared to inkjet printed tracks. The biopolymer–ink interaction results in narrower printed tracks compared to those on glass. This affects the final conductivity, which is lower for printed tracks on biopolymer than for lines printed on glass, due to the part of the track lying below the surface. Extrusion printing is used to embed tracks into a biopolymer matrix, resulting in significant improvement in electrical characteristics. The electrical conductivity of embedded tracks (17 S cm1) is an order of magnitude higher than for track deposition on the surface of biopolymer film and 3 times higher than for tracks on glass.

The necessity of keeping a competitive edge against other means of transportation has increased the pressure on the railway industry to improve its efficiency and decrease maintenance and infrastructure costs. A comprehensive research program was launched at the University of Wollongong (UoW), sponsored by the Australian Cooperative Research Center for Railway Engineering and Technologies to investigate various methods to stabalise tracks underlying soft soil formation. The research findings show that the bonded geogrids-geotextiles can improve the performance of ballasted tracks and the installation of prefabricated vertical drains in soft formation can reduce the preloading period significantly. According to experimental and field trial investigations it has been found that the ballast deformation and breakage can be reduced if appropriate ballast grading and track confining pressure are applied.

The necessity of keeping a competitive edge against other means of transportation has increased the pressure on the railway industry to improve its efficiency and decrease maintenance and infrastructure costs. A comprehensive research program was launched at the University of Wollongong (UoW), sponsored by the Australian Cooperative Research Center for Railway Engineering and Technologies to investigate various methods to stabalise tracks underlying soft soil formation. The research findings show that the bonded geogrids-geotextiles can improve the performance of ballasted tracks and the installation of prefabricated vertical drains in soft formation can reduce the preloading period significantly. According to experimental and field trial investigations it has been found that the ballast deformation and breakage can be reduced if appropriate ballast grading and track confining pressure are applied.

The necessity of keeping a competitive edge against other means of transportation has increased the pressure on the railway industry to improve its efficiency and decrease maintenance and infrastructure costs. A comprehensive research program was launched at the University of Wollongong (UoW), sponsored by the Australian Cooperative Research Center for Railway Engineering and Technologies to investigate various methods to stabalise tracks underlying soft soil formation. The research findings show that the bonded geogrids-geotextiles can improve the performance of ballasted tracks and the installation of prefabricated vertical drains in soft formation can reduce the preloading period significantly. According to experimental and field trial investigations it has been found that the ballast deformation and breakage can be reduced if appropriate ballast grading and track confining pressure are applied.

Assessment of condition of railway track is crucial for track design, repair, and effective maintenance operations. In-field dynamic testing in combination with track modelling represents an efficient strategy for identification of the current condition of railway track structure and its components. Field investigations for the dynamic characteristics of a railway track and its components were carried out and are presented in this paper. A non-destructive technique using impact excitation, so-called modal testing, was utilized in these trials. Integrated approach combining field measurements, experimental modal analysis, and finite element modelling to evaluate the dynamic parameters of the in situ railway track components are appended. A ballasted railway track site in Central Queensland managed by Queensland Rail (QR) was selected to perform the field tests. Six sleeper-fastening-rail assemblies were selected for dynamic testing. The frequency response functions (FRFs) were recorded by using Bruel Kjaer PULSE vibration analyser in a frequency domain between 0 and 1600 Hz. The data obtained were best fitted using the least-square technique to determine the dynamic stiffness and damping constants of the tested track components. In addition, the experimentally determined resonance frequencies along with the dynamic properties of the track components can provide an important input for determining the maximum speed and axle load for the future track upgrades. This paper also points out on how to judge the dynamic responses (e.g. FRFs) together with the visual inspection of existing conditions from the field experience. Examples of testing results representing the deficient integrity are additionally highlighted. Based on the results, the impact excitation technique is an efficient method susceptible to the structural integrity of railway track structures.>

Assessment of condition of railway track is crucial for track design, repair, and effective maintenance operations. In-field dynamic testing in combination with track modelling represents an efficient strategy for identification of the current condition of railway track structure and its components. Field investigations for the dynamic characteristics of a railway track and its components were carried out and are presented in this paper. A non-destructive technique using impact excitation, so-called modal testing, was utilized in these trials. Integrated approach combining field measurements, experimental modal analysis, and finite element modelling to evaluate the dynamic parameters of the in situ railway track components are appended. A ballasted railway track site in Central Queensland managed by Queensland Rail (QR) was selected to perform the field tests. Six sleeper-fastening-rail assemblies were selected for dynamic testing. The frequency response functions (FRFs) were recorded by using Bruel Kjaer PULSE vibration analyser in a frequency domain between 0 and 1600 Hz. The data obtained were best fitted using the least-square technique to determine the dynamic stiffness and damping constants of the tested track components. In addition, the experimentally determined resonance frequencies along with the dynamic properties of the track components can provide an important input for determining the maximum speed and axle load for the future track upgrades. This paper also points out on how to judge the dynamic responses (e.g. FRFs) together with the visual inspection of existing conditions from the field experience. Examples of testing results representing the deficient integrity are additionally highlighted. Based on the results, the impact excitation technique is an efficient method susceptible to the structural integrity of railway track structures.>

Assessment of condition of railway track is crucial for track design, repair, and effective maintenance operations. In-field dynamic testing in combination with track modelling represents an efficient strategy for identification of the current condition of railway track structure and its components. Field investigations for the dynamic characteristics of a railway track and its components were carried out and are presented in this paper. A non-destructive technique using impact excitation, so-called modal testing, was utilized in these trials. Integrated approach combining field measurements, experimental modal analysis, and finite element modelling to evaluate the dynamic parameters of the in situ railway track components are appended. A ballasted railway track site in Central Queensland managed by Queensland Rail (QR) was selected to perform the field tests. Six sleeper-fastening-rail assemblies were selected for dynamic testing. The frequency response functions (FRFs) were recorded by using Bruel Kjaer PULSE vibration analyser in a frequency domain between 0 and 1600 Hz. The data obtained were best fitted using the least-square technique to determine the dynamic stiffness and damping constants of the tested track components. In addition, the experimentally determined resonance frequencies along with the dynamic properties of the track components can provide an important input for determining the maximum speed and axle load for the future track upgrades. This paper also points out on how to judge the dynamic responses (e.g. FRFs) together with the visual inspection of existing conditions from the field experience. Examples of testing results representing the deficient integrity are additionally highlighted. Based on the results, the impact excitation technique is an efficient method susceptible to the structural integrity of railway track structures.>

Assessment of condition of railway track is crucial for track design, repair, and effective maintenance operations. In-field dynamic testing in combination with track modelling represents an efficient strategy for identification of the current condition of railway track structure and its components. Field investigations for the dynamic characteristics of a railway track and its components were carried out and are presented in this paper. A non-destructive technique using impact excitation, so-called modal testing, was utilized in these trials. Integrated approach combining field measurements, experimental modal analysis, and finite element modelling to evaluate the dynamic parameters of the in situ railway track components are appended. A ballasted railway track site in Central Queensland managed by Queensland Rail (QR) was selected to perform the field tests. Six sleeper-fastening-rail assemblies were selected for dynamic testing. The frequency response functions (FRFs) were recorded by using Bruel Kjaer PULSE vibration analyser in a frequency domain between 0 and 1600 Hz. The data obtained were best fitted using the least-square technique to determine the dynamic stiffness and damping constants of the tested track components. In addition, the experimentally determined resonance frequencies along with the dynamic properties of the track components can provide an important input for determining the maximum speed and axle load for the future track upgrades. This paper also points out on how to judge the dynamic responses (e.g. FRFs) together with the visual inspection of existing conditions from the field experience. Examples of testing results representing the deficient integrity are additionally highlighted. Based on the results, the impact excitation technique is an efficient method susceptible to the structural integrity of railway track structures.>

Discussing experimental procedures as well as theoretical aspects, Mechanics of Ballasted Tracks: A Geotechnical Perspective presents the state-of-the-art triaxial testing of ballast, including strength, deformation, and degradation aspects of fresh and recycled ballast. This book provides an in-depth examination of the effectiveness of geosynthetics in stabilizing recycled ballast. Incorporating particle breakage, it presents a new stress-strain constitutive model for ballast. Beneficial for practicing engineers as well as engineering students, this text also proposes a new range of particle gradations for future rail tracks that balances strength and permeability requirements.

Discussing experimental procedures as well as theoretical aspects, Mechanics of Ballasted Tracks: A Geotechnical Perspective presents the state-of-the-art triaxial testing of ballast, including strength, deformation, and degradation aspects of fresh and recycled ballast. This book provides an in-depth examination of the effectiveness of geosynthetics in stabilizing recycled ballast. Incorporating particle breakage, it presents a new stress-strain constitutive model for ballast. Beneficial for practicing engineers as well as engineering students, this text also proposes a new range of particle gradations for future rail tracks that balances strength and permeability requirements.

Discussing experimental procedures as well as theoretical aspects, Mechanics of Ballasted Tracks: A Geotechnical Perspective presents the state-of-the-art triaxial testing of ballast, including strength, deformation, and degradation aspects of fresh and recycled ballast. This book provides an in-depth examination of the effectiveness of geosynthetics in stabilizing recycled ballast. Incorporating particle breakage, it presents a new stress-strain constitutive model for ballast. Beneficial for practicing engineers as well as engineering students, this text also proposes a new range of particle gradations for future rail tracks that balances strength and permeability requirements.

Discussing experimental procedures as well as theoretical aspects, Mechanics of Ballasted Tracks: A Geotechnical Perspective presents the state-of-the-art triaxial testing of ballast, including strength, deformation, and degradation aspects of fresh and recycled ballast. This book provides an in-depth examination of the effectiveness of geosynthetics in stabilizing recycled ballast. Incorporating particle breakage, it presents a new stress-strain constitutive model for ballast. Beneficial for practicing engineers as well as engineering students, this text also proposes a new range of particle gradations for future rail tracks that balances strength and permeability requirements.