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The excavation of large-scale lacustrine soft soil in natural state in the Chengmenshan Copper mine, Jiujiang, China, is a challenging work and is illustrated in this paper. A geometrical model of the lacustrine soft soil was built based on data from more than 150 boreholes. A series of tests were conducted on the natural soft soil including compaction, consolidation and common test, and also remolded samples containing water contents of 10%, 13%, 16%, 21%, 25%, 30% and 37% were tested. Results showed that the cohesion and friction angle decrease rapidly with the increase in water content, but the consolidation pressure played a positive role to the increase in shear strength. To properly manage the soil properties and optimize the surcharge program, settlement and uplift during the infill construction were numerically analyzed by means of SIGMA/W. Based on the test and numerical simulation results, a long term in situ improvement method was proposed and performed. Finally, drilling sampling tests, settlement monitoring and slope stability analysis were conducted to evaluate the overall effects of the surcharge. The properties of the soft soil were improved greatly under the infill surcharge, especially the cohesion and frictional increased by 279.3% and 152.8% and almost reached the value of remolded soil after consolidation under pressure 300 kPa. The settlement rate decreased with the surcharge duration. The safety factor of slope after improvement also met the design requirement. Furthermore, the method proposed in this paper which have given consideration to economic conservation and environmental protection is significant for the soft soil excavation projects. [ABSTRACT FROM AUTHOR]

The prefabricated vertical drain (PVD) is an essential means to mitigate the settlement of soft soil foundations in coastal areas of South China. The commonly used elastoplastic analytical method cannot directly reflect the interaction of different PVDs and the resulting displacement of soft soil. At the same time, these elastoplastic analysis and numerical simulation methods are greatly influenced by the values adopted for rock and soil material parameters. In this paper, we present a stochastic medium model that can directly reflect the interaction of different PVDs and the resulting displacement of soft soil. It is not affected by the characteristics of rock and soil themselves and can also reflect the actual deformation process of soft soil. According to engineering practice, the settlement curves of soft soil foundations in coastal areas of South China with PVDs exhibited distinct normal distribution characteristics, which was consistent with the description of settlement by the stochastic medium model. Hence, based on the stochastic medium model, this paper analyzed the settlement mechanism of PVDs and established a stochastic medium model for the settlement calculation of PVDs. A function for the soft soil foundation in the coastal area of South China cross-section settlement curve was presented by back analysis of the PVD model. We chose the stochastic medium model based on this methodology to explore the interaction between different PVDs. The above models were then applied to an expressway in South China. Comparing actual settlement monitoring values to calculated values obtained with the PVD model, the error between the two models was less than 15%. This research provides a new settlement calculation method of PVDs in soft soil foundations in the coastal area of South China and a new basis for designing soft soil foundations. [ABSTRACT FROM AUTHOR]

This case study focuses on an International Circuit project in China where unmanned automobiles are to be tested in the future. The subgrade undergoes extensive settlement because of the widely distributed lacustrine deposits with high void ratio and compressibility. Prestressed high-strength concrete (PHC) pile-supported earth platforms are used for ground improvement in this area, but their effectiveness has not yet been confirmed. Associated with this adoption, the negative skin friction (NSF) of the piles and the related neutral plane (NP) position is of importance. Although NSF has been examined in detail, the NP position has not, especially with regard to its time dependence. This paper reports the settlement of the pile-supported soft soil subgrade as obtained from long-term observations of full-scale tests. The NP position is determined according to the layered settlement of the soil and the pile settlement, both of which are obtained from long-term field observations. The results reveal that the NP position has a clear time dependence that develops in stages. The NP is initially elevated with time, and then it gradually approaches a constant value. The existing models fail to predict this time dependence of the NP position in the studied sites. A exponential model is used, the fitting parameters of which have practical implications. The adopted model works well with the studied sites, especially in terms of reflecting the time dependence of the NP position and distinguishing the different stages of its development. This paper enhances the understanding of the NP and provides a reference data set for related engineering practices. [ABSTRACT FROM AUTHOR]

A reclamation project was undertaken in Zhuhai, China, covering an area of 11.35 km2 with a clay-slurry thickness of 30 m. It is interesting to find a good reinforcement method, which is more suitable for strengthening such a large-scale dredged clay-slurry ground. Evidence from engineering practice shows that vacuum preloading or vacuum preloading combined with surcharge preloading method technology has certain advantages. However, further data is required to verify their performance in the field. This paper presents a case study using the conventional vacuum preloading and vacuum preloading combined with surcharge preloading method (vacuum pressure of 90 kPa, surcharge height of 3 m) to improve the thick clay-slurry ground for a subgrade engineering project in Zhuhai, China. A series of field monitoring, in-situ tests, and laboratory tests were performed to evaluate their treatment effect by analysis of vacuum degree, ground surface settlement, layered settlement, consolidation degree, lateral displacement, excess pore water pressure dissipation, and vane shear strength. The results showed that the ground treated via vacuum preloading combined with surcharge preloading method was more effective than conventional vacuum preloading. The vacuum degree of vacuum preloading combined with surcharge preloading method was slightly lower than that of conventional vacuum preloading, decreasing with depth. The settlement is increased by 55.56%, average consolidation degree is enlarged by 40.9%, lateral displacement can be augmented by 2.4 times, pore water pressure coefficient is less than 0.6, and undrained shear strength is amplified by 22.2%. These findings can be used to guide the design of the combined preloading method of the subgrade engineering project along the east coast of China. [ABSTRACT FROM AUTHOR]

The site earthquake often causes serious soil liquefaction, especially results in volume change and surface subsidence to cause many secondary disasters. Different from the previous research on volume strain settlement of remolded clean sand after liquefaction, this paper adopts a gel push sampler to obtain undisturbed silt samples with fine particles in Xiong'an New Area of China. Dynamic triaxial tests are carried out on undisturbed and remodeling model soil samples. After the liquefaction failure of the test body occurs, the postliquefaction volumetric strain is measured. Based on the relevant test data, the volume strain characteristics of low plastic silt with fine particles after liquefaction are compared and discussed. The results show that cyclic stress ratio (CSR) is proportional to γmax at the time of failure. The threshold value of the maximum shear stress of the remolded sample is 3.75%, while it is about 7.5% for the undisturbed low plastic silt sample. The repeated shear stress of the undisturbed sample is higher than that of the remolded sample. When the shear strain increases to a certain value, the volume strain tends to a fixed value after liquefaction. The volume strain caused by liquefaction of low plasticity remolded and undisturbed samples is significantly higher than that of clean sand. The maximum shear strain increases with the decrease of liquefaction safety factor. It underestimates the settlement after liquefaction by remolded clean sand or remolded soil sample, and the undisturbed soil sample as the engineering design basis is more in line with the actual soil condition. [ABSTRACT FROM AUTHOR]

This paper draws on in-depth interviews undertaken eight years apart to provide a reflection upon the nature of transnational relationships and settlement over time. It follows the lives of five immigrant families between 1999 and 2007, and focuses in particular on the accounts provided by the women. These individuals migrated to Canada from Hong Kong or Taiwan during the 1990s, and then 'stuck it out', when most of their friends, in contrast, had returned home. The paper uncovers changes in their familial and personal circumstances as a consequence of migration to Canada and their subsequent experiences of transnationalism, and provides insights into the longevity and durability of transnational relationships. It contributes to debates around the persistence of transnationalism over time and the relationship between transnationalism and integration for migrants, whilst also making a methodological point about the need for more longitudinal qualitative accounts of immigrants' lives. [ABSTRACT FROM AUTHOR]

With the gradual densification of China's railway network, more and more railways are inevitably crossing active fault zones. Creep dislocation and stick–slip dislocation of the fault zones can lead to uneven deformation and cracks in the railway subgrade, threatening the sustainability of the railway. Therefore, a model test and numerical simulation were used to analyze the deformation mechanism and sustainability of the subgrade and foundation induced by a strike–slip fault dislocation in a flat site under different angles between the subgrade and fault strikes. The test and simulation results show that (1) under the influence of strike–slip fault dislocation, the horizontal direction of the subgrade appeared to have an S–shaped displacement. The top surface of the subgrade appeared to have a vertical settlement. Further, tension–shear cracks and compression crush zones appeared on the subgrade's surface. (2) When the angle between the fault and subgrade strikes increased, the subgrade's uneven deformations induced by fault dislocation first decreased and then increased. The angle between the main tension–shear crack on the top surface of the subgrade and the fault strike showed a trend of increasing and then decreasing. In addition, the compressive stress along the subgrade strike decreased, while the tensile stress along the subgrade strike gradually increased. (3) The tension–shear cracks in the subgrade and foundation were spiral and converged to the basement strike–slip fault along the depth direction. This study provides a reference for the safe operation and sustainability of railways near faults. [ABSTRACT FROM AUTHOR]

The Qinghai-Tibet railway, the highest railway in terms of elevation, was built under the harshest of weather conditions in the world. A new technique, called the ventiduct embankment, was used for the first time in railway construction in the Qinghai-Tibet permafrost region of China to overcome the specific difficulties of the permafrost plateau. To evaluate its effectiveness, several full-scale test embankments were constructed at a representative field site, the Qingshuihe experimental section. The effectiveness of the ventiduct embankment structure has been verified by comparing it with the performance of the nearby control embankment in terms of permafrost table, settlement, and thaw depth. These observations are presented in this paper. The ventiduct embankment structure based on this study has been adopted in Qinghai-Tibet permafrost railway construction. [ABSTRACT FROM AUTHOR]

Due to the rapid urbanization of China, many villages in the urban fringe are enveloped by ever-expanding cities and become so-called urban villages (UVs) with substandard living conditions. Despite physical similarities to informal settlements in other countries (e.g., slums in India), UVs have access to basic public services, and more importantly, villagers own the land legitimately. The resulting socio-economic impact on urban development attracts increasing interest. However, the identification of UVs in previous studies relies on fieldwork, leading to late and incomplete analyses. In this paper, we present three scene-based methods for detecting UVs using high-resolution remotely sensed imagery based on a novel multi-index scene model and two popular scene models, i.e., bag-of-visual-words and supervised latent Dirichlet allocation. In the experiments, our index-based approach produced Kappa values around 0.82 and outperformed conventional models both quantitatively and visually. Moreover, we performed multitemporal classification to evaluate the transferability of training samples across multitemporal images with respect to three methods, and the index-based approach yielded best results again. Finally, using the detection results, we conducted a systematic spatiotemporal analysis of UVs in Shenzhen and Wuhan, two mega cities of China. At the city level, we observe the decline of UVs in urban areas over the recent years. At the block level, we characterize UVs quantitatively from physical and geometrical perspectives and investigate the relationships between UVs and other geographic features. In both levels, the comparison between UVs in Shenzhen and Wuhan is made, and the variations within and across cities are revealed. [ABSTRACT FROM PUBLISHER]

Karst landscapes are widely distributed in China, and buried karst is widespread in Guangdong. This study mainly focuses on buried karst or karst caves which are underground at depths of up to 50 m and can significantly affect engineering construction activity. The karst caves, which are widely distributed in Guangdong Province, have the following features: high fissure water content, high rock permeability, prone to collapse, variable shapes, and irregular distribution. When a shield tunnel is constructed in this kind of environment, hazards, such as sink holes, the ingress of water or stones, and damage to the constructed tunnels may occur. Thus, karst caves need to be treated before tunnel construction. This paper presents a procedure for karst cave treatment to mitigate possible hazards during shield tunnelling in karst regions. The construction procedure includes field investigation, judgment, treatment, and effectiveness check. The treatment criteria, grouting material, construction steps, and effectiveness check for the karst cave treatment are introduced in detail. A field test on shield tunnelling excavation was conducted using the karst cave treatment in the karst region of Guangzhou, China. Field investigations include testing the unconfined compressive strength (UCS) of borehole samples of grouting materials, standard penetration test (SPT), core recovery (CR), ground surface settlement and building settlement. All of the UCS values of the borehole samples are greater than 0.2 MPa, the modified SPT values are more than ten, and the CR values are greater than 90 %. The measured values of ground surface settlement and building settlement are all within the allowable ranges. All of the test results demonstrate the applicability of this treatment process in karst regions. [ABSTRACT FROM AUTHOR]

Based on engineering practices of four typical traffic immersed tunnels built in China, this paper details the features of the four dominant foundation treatment methods for immersed tunnel construction: pile foundation, sand flow foundation, grouting foundation, and gravel bedding foundation. Subsoil stress time-history of different method are specified first, plus a summary of settlement assessment method for foundation quality control. Further, a comprehensive comparison of settlement and cost of these four foundation treatment methods is conducted to highlights the specific merits, disadvantages and conditions encountered in each foundation treatment method, based on real projects information. The findings of this article could henceforth be applied to foundation treatment work in immersed tube tunnel construction. [ABSTRACT FROM AUTHOR]

The relocation of rural people away from marginal or fragile lands is an increasingly common approach used in China to achieve environmental protection and development objectives. However at present few studies have been made of the social impacts of such resettlement projects in China. Several key social dimensions of a significant resettlement project in the Tibet Autonomous Region are therefore analysed and discussed in this paper. It was specifically posited that the research findings presented here would (1) provide useful guidance for local government offices and government staff workers who are engaged in poverty reduction and agricultural development work; and (2) help to give residents of the community under consideration more voice and opportunity to interact with the outside world. A field survey was designed and led by the lead author in June 2009, with semi-structured interviews and a questionnaire, to ascertain the present situation in the target village and thus help to provide a useful basis for future policy recommendations. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Engineering Geology & the Environment is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the increasingly stringent requirements lor environmental protection in China, the research on dredged soil treatment technology has become a hot spot. A new type of embankment with mud—sand interhedded structure is put forward in this paper. The dredged soil is filled with membrane bag and interhedded with sandy membrane bag, which gradually forms a new stable embankment core structure. Through the finite element simulation results, it is known that after 55 d of consolidation, the maximum displacement of mud—sand interhedded structure is 2.73 in, and the top surface of the mud—sand inteibedded structure is 1.9 in from the back surface. The compression of the mud—sand interhedded structure is mainly occurs in the middle of the body, and the bottom and top are less compressed. The design and construction of the embankment meets the engineering requirements, and it is a feasible and last embankment technology on soft soil foundation. [ABSTRACT FROM AUTHOR]

This paper considers economic models of migration in the context of current Chinese migration. We argue that using formally changing one's household registration (hukou) location is too narrow a definition of settlement for policy purposes. Instead we show that time in the city and co-residence with spouses and separately with children reveals systematic settlement behavior on the part of a subset of migrants. The empirical evidence offered is largely descriptive but shows that those migrants who were younger at the age of migration, who are currently married and self-employed spend more years in the city. Men who have been in the city longer and are self-employed are much more likely to be co-residing with their wife. Self-employment is also a predictor of co-residence with children for both mothers and fathers. [ABSTRACT FROM AUTHOR]

The driven cast-in-situ concrete thin-wall pipe pile (PCC) is a new technique for soft ground improvement and has been recently approached in China. It has become one of the most cost-effective soft soil improvement methods that can increase the bearing capacity and reduce the settlement of the soil. This paper presents a field application in a highway foundation improvement project. The field study has demonstrated that PCC pile composite foundation is a cost-effective way of improvement. The cast-in-PCC composite foundation piles; design theory, construction technology and monitoring are described. From the test results of cast-in-reinforcement it is clearly easier to control and the PCC technology is economically advantageous. The advantages of the method are proposed to be promoted in expressway construction to have greater social and economic benefits in the world. [ABSTRACT FROM AUTHOR]

When designing embankments over soft soils, geotechnical engineers face many challenges. These include potential bearing failure, intolerable settlement, and global or local instability. Pile-supported embankments have been emerged as an effective alternative successfully adopted worldwide to solve these problems. This paper focuses on three cases in which pile-supported embankments were used for constructing highways in the eastern coastal region of China. Each case provides a description of the soil profile, construction procedure, and field monitoring of the settlements, earth pressures, and pore-water pressures. Field monitored data from contact pressures acting on the piles and the soils, to the settlements of the piles and the soils are reported and discussed. The development of the earth pressures both on the piles and the soils shows that there was a significant soil arching in the embankment, and the measured earth pressures acting on the piles are much higher than that acting on the soils between the piles. The measured differential settlements between the piles and the soils are small. The pore-water pressures are not significant compared to the embankment loads. Most pore-water pressure dissipated after the complete of filling. The measurements have proven the effectiveness of this technique in reducing total and differential settlements. Finally, the available design standards and approaches are verified by three cases. [ABSTRACT FROM AUTHOR]

Constructing concrete-faced rockfill dams (CFRDs) with weak rocks has great advantages as a result of the use of local materials, cost-effectiveness, extensive adaptability, simple construction, and short construction period. However, the behaviors of CFRDs constructed with weak rocks are not well-understood. This paper reports the physical, mechanical, and hydraulic properties of weak rockfill during placement and compaction in three dam projects in China. These properties were obtained from laboratory and field tests. Important considerations, such as the control of crushing and crusting and the increase of the permeability of weak rocks, are discussed. Numerical studies on the settlements and slope stability of the dams were conducted and their results were compared with the field measurements. This study provides the opportunities for further understanding the behaviors of CFRDs with weak rocks. [ABSTRACT FROM AUTHOR]

This paper models consolidation of the foundation soils under a test embankment at the new Chek Lap Kok International Airport in Hong Kong. The modelling used a simplified finite element method and material parameters derived from results in the original site investigation report. Various features that need to be considered in applying the simplified method are illustrated through this case study. Good predictions of settlement results are obtained. Relatively large discrepancies in pore-water pressure predictions suggest that the nonlinear nature of hydraulic conductivity needs to be taken into account when large compressions are likely to occur. Geological conditions are shown to be a key factor in successful modelling of consolidation behaviour.Key words: consolidation, pore-water pressure, case modelling, finite element method, vertical drains, settlement.Cet article modélise la consolidation des sols de fondation sous un remblai d'essai au nouvel aéroport international Chek Lap Kok de Hong Kong. La modélisation a utilisé une méthode simplifiée d'éléments finis et des paramètres du matériau dérivés des résultats du rapport de l'investigation originale du site. Diverses caractéristiques qui doivent être considérées dans l'application de la méthode simplifiée sont illustrées dans cette étude de cas. De bonnes prédictions des résultats de tassement ont été obtenues. Des divergences relativement importantes dans les prédictions des pressions interstitielles portent à penser que la nature non linéaire de la conductivité hydraulique doit être prise en compte lorsque des compressions importantes peuvent vraisemblablement se produire. On montre que les conditions géologiques sont un facteur clé pour modéliser avec succès le comportement en consolidation.Mots clés : consolidation, pression interstitielle, modélisation de cas, méthode d'éléments finis, drains verticaux, tassement.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

The settlement of South China Sea disputes by the International Arbitration Board is a complex challenge. The South China Sea is a strategic area disputed by several countries in Southeast Asia. International Arbitration Bodies play an important role in handling these disputes. Arbitration proceedings began in 2013 and a decision was announced in 2016. Although the decree is legally binding, its implementation still faces political and diplomatic challenges. Cooperation between the countries involved is necessary to achieve an effective solution. [ABSTRACT FROM AUTHOR]

Suction caisson foundations are increasingly considered as a foundation solution for offshore wind farm development in China. This paper outlines the design considerations for developing a suction caisson supported jacket solution for an offshore wind farm in Southern China. Geotechnical analyses for four major aspects, ultimate limit state (ULS), serviceability limit state (SLS), fatigue limit state (FLS) and installation are discussed. The design challenges encountered in the project due to soft seabed and metocean characteristics (severe typhoon loading and dominant wind directions) and technical approaches adopted by the project are presented. Areas for further studies are identified and discussed. The purpose of this paper is to disseminate this knowledge and raise awareness of several important aspects. [ABSTRACT FROM AUTHOR]

This study examines the changing role of traditional employment sector and the access to employment‐related citizenship rights in affecting migrant workers' settlement intentions in China. Traditionally, migrants who are informally employed were viewed as unsettled groups in Chinese cities. However, the expanded employment‐related citizenship rights provide more diverse channels for pursuing permanent urban settlement. We use data from China Migrants Dynamic Survey in 2013 to investigate migrant workers' permanent settlement intentions, taking into account their access to employment‐related citizenship rights, employment sector, hukou status, social‐economic attachments at the places of destination and origin, and regional variations. We found that self‐employed and informally employed migrants held a stronger intention to pursue permanent settlement if they were protected by the local urban insurance schemes, the so‐called "de facto" employment‐related citizenship. The study suggests that the dichotomy of employment sectors, formal versus informal, in understanding migrants' settlement decision has been weakened in China. [ABSTRACT FROM AUTHOR]

Abstract: Settlement is one of the most important deformation characteristics of a high concrete-face rockfill dam (CFRD) and is regarded as a key indicator of dam safety. The time-dependent settlement behavior of the Shuibuya CFRD is studied on the basis of in situ settlement-monitoring records and displacement back-analysis. The goal of this work is to characterize actual deformation of the dam and to verify the back-analysis method used in this paper. The settlement-monitoring records were from seven control stations at the crest and 38 monitoring points inside the body of the dam and covered the construction period, the initial filling of the reservoir and 2years of operation. A displacement back-analysis for parameters is performed by hybrid generic algorithms (HGAs) and finite element method (FEM). Comparative studies of monitoring data and back-analysis show good agreement between measured settlements and computed settlements. Furthermore, the deformation in the next 3years is predicted on the basis of back-analysis. Overall, it is demonstrated that the deformation of the Shuibuya CFRD is basically stable and that the technique used to control the dam deformation is successful. [Copyright &y& Elsevier]

Abstract: An in situ testing of a selected railway embankment in Qingshuihe region, Tibet Plateau, is described where no artificial protection measure was employed. Based on the results obtained, characteristics of the distribution of geotemperature and settlement of the embankment are examined. An assessment of long-term stability of the embankment is made, and a kind of efficient engineering treatment is recommended in this paper. The study reveals: a) although the permafrost table did not move after embankment construction, the layer between ground surface and the permafrost table approached the phase-transition critical state, i.e. 0.0 °C. This layer is about 3.0 m thick, and is the major source of embankment settlement; b) the varying heat-absorption at different locations along the cross-section of the embankment leads to a differential settlement, and results in the longitudinal cracking; c) the settlement developed at a constant rate (about 0.06 m/year in the middle of the embankment) during the complete test period; d) the optimal railway embankment height differs from that for highways, and should be less. Further study of the optimal height should be carried out comprehensively and the results applied to engineering practice immediately, since this could not only keep the permafrost table stable but also limit the differential settlement to an acceptable level; e) asymmetrical protection measures should be employed to reduce the differential settlement and longitudinal cracking; f) it is most important that embankment construction in permafrost area be carried out during the cold season. [Copyright &y& Elsevier]

Rockfill dams are generally constructed on thick overburden layers in mountainous and valley areas due to their high adaptability to complex geological and geographical conditions. The safety of rockfill dams is a research focus worldwide, especially with the increase of dam heights. Significant differential settlement may be induced by different embankment materials in a dam body and various stratum properties in thick overburden layers. The accurate prediction of settlement is particularly important to guarantee the serviceability and safety operation of rockfill dams. Therefore, a novel settlement forecasting model is proposed in this study. This model can achieve a successful prediction of dam settlement during the construction and operation periods. Compared with the traditional model, the settlement influential factors in the proposed model are determined based on the existing theory of coarse-grained soil deformation calculation, causing the selection of factors to have clearer physical meanings. Additionally, the geometric characteristics of the dam, the different material properties in various zones of the dam and the foundation, and the complicated external loading conditions are all considered. Then, the improved regression model for forecasting the settlement of dams is proposed. The proposed settlement forecasting model is further employed to estimate the deformation of a high rockfill dam in China. The results prove that this novel method shows high accuracy and agrees well with the monitoring consequences, and this method is superior to the traditional statistical regression model in predicting dam settlement during the construction period. [ABSTRACT FROM AUTHOR]

China's high-speed railway has become world-famous, how to realize the safe operation of the high-speed railway passing through the mined-out areas in China will face many new challenges. To reveal the deformation and dynamic response characteristics of the track-structure and subgrade of the high-speed railway above the mined-out areas, the modeling method of transient vibration in ABAQUS was proposed, and the three-dimension computational model was built. The deformation characteristics, spatiotemporal evolution mechanism, and the law of interlayer separation under different wavelengths and amplitudes of uneven settlement of the subgrade of the high-speed railway were analyzed. The curvature radius was proposed to characterize the separation between the trackstructure and the subgrade comprehensively. Results show that the deflection of the track structure is comprehensively controlled by the wavelength and amplitude of the foundation settlement. When the wavelength is greater than 30 m and the amplitude is less than 0.9 m, the deflection of the track-structure increases from fast to slow and gradually tends to be stable, and it can keep a high following with the subgrade. The separation between the track structure and the subgrade is more prominent when the radius of curvature is less than 200 m. Otherwise, it is very weak. In addition, the dynamic response of the track structure in the separated section is more intense than that in the unseparated section. The conclusions obtained in this study can provide the reference for the construction of the high-speed railway above the mined-out areas. [ABSTRACT FROM AUTHOR]

In ancient China, as elsewhere, states did not simply occupy a given territory but actively engaged in the production of space by transforming landscapes, moving populations, and enacting territorial hierarchies, thus creating "state spaces," to borrow a term coined by James C. Scott. In the case of the early Chinese empires of Qin (221–207 BCE) and Han (202 BCE–220 CE), state-induced migration and settlement were key instruments of military control, administrative incorporation, economic intensification, and other processes connected with spatial distribution of state power. This article combines insights from transmitted texts, excavated documents, and archaeological evidence to explore factors and effects of migration in early Chinese empires, discussing the interconnection between state-organized resettlement and private migration as well as their embeddedness in the local geography. As the situation varies according to location, the present article introduces the approach and tests it on a case study, the Guanzhong metropolitan region. [ABSTRACT FROM AUTHOR]

Dredging activities in China produce a great deal of clay suspensions which are generally pumped into yards as filling materials to form reclaimed lands. Understanding the settlement behavior of clay suspensions during settling process is essential in engineering practice for meeting the design requirement on the storage capacity of reclaimed yards. To this end, this study performed 25 types of sedimentation tests on the clay suspensions with different liquid limits, initial water contents, and initial heights using different sizes of sediment columns. The experimental results indicate that the settlement–time curves of clay suspensions can be classified into three stages. It is found that the first stage can be ignored, and the sedimentation can be attributed to the second stage termed as settling stage in practice. Hyperbolic model is proposed for describing the settlement–time relationship during the settling stage, and a quantitative method of determining the settlement at the end of the settling stage is suggested. The changing trends of the settlement and the time at the completion of sedimentation are investigated with considering the effects of liquid limit, initial water content, and initial height. [ABSTRACT FROM AUTHOR]

Renminbi (RMB) internationalisation is at a new starting point for advancing further. Wider internationalisation of the renminbi necessitates enlarging the offshore basis. Hong Kong as the sole RMB offshore centre is not enough, given its limitations. This has sparked an intensive debate on where the next RMB offshore trading centre will be located. London has support from Chinese central government officials to develop into a second offshore RMB hub to complement Hong Kong. But other financial centres are also vying to become such a centre. A number of private- public initiatives have been launched such as the Hong Kong-London Forum (January 2012) and the so-called London-RMB Initiative (April 2012) to help realise that ambition technically. London offers a number of important advantages compared with other rivals. There is London's dominant position as the world's leading global financial centre, as well as the world's largest foreign exchange market. London also has well-developed infrastructure, a trusted legal system and respected (sound) regulatory framework. There are the 'natural' advantages of London's time zone, as well as English being the universal business language. Its attractiveness is further underpinned by key strengths such as size, depth, breadth as well as the high degree of openness of its financial markets. London is clearly making a big effort to establish itself as an offshore RMB centre for the west. A significant amount of RMB business is already being done in London. The City, however, encounters a number of obstacles that pose challenges for RMB business in London. These include the lack of RMB liquidity, absence of a clearing and settlement system for RMB repatriations in London, and the lack of a natural customer base for RMB. A more recent challenge for London is the expected end of appreciation for the RMB. [ABSTRACT FROM AUTHOR]

Seen in the built environment of village and towns, the plans of scientific texts and journals of modern animal husbandry, and in the programmes of state natural resource bureaucracies and international development projects, settlements constructed for nomadic peoples in China seem to index a historically and socially specific vision associated with modern political economic ideologies. Drawing on the work of James Scott (1996), one might argue that settlement is the vision of the Chinese state. Yet Scott's approach risks objectifying the embodied vision of the humans who constitute settlement. Indeed, many scholars have simplified the agency attributed to a range of actors within the experience of settlement. This article uses a phenomenological approach to make more complex our understandings of these phenomena by exploring perceptions of settlement among three distinct actors: officials from the Chinese states, personnel of international organizations which have funded and provided technical expertise in the implementation of settlements, and residents of settlements themselves – Chinese ethnic minority citizens. In conclusion, I offer three different but overlapping visions that make settlement as a totality possible, and yet distinct from an objectified vision of Chinese government officials. [ABSTRACT FROM AUTHOR]

This article discusses the sources, processes and impact of the quality assurance policy implemented in Hong Kong preschools. Regarded as a sort of policy alignment between the subsystems of pre-primary, primary and secondary education, the introduction of a quality assurance policy has been directly and indirectly transforming the settlements in the preschool context. The first section of this article examines the main shift in policy direction shaped by the global movement of supranational organizations and the local agenda of educational reform after 1997. The historical review of the changing parameters in the preschool field is provided in the second section as a backdrop for later discussion. The third section analyses how the local governance of education is subtly transforming the settlements in the preschool field. The fourth section discusses how the quality assurance policy is mediated with school-level realities. It is argued that the top-down approach adopted by policy-makers should be critically re-examined in the policy process in order to ensure the quality of preschool education. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Geotechnical Journal is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)