Using 3D seismic exploration to detect ground fissure

   As a kind of supergene geological phenomenon, ground fissure has brought great inconvenience to human life. In addition, it also has a close relationship with earthquake. However, it is very difficult to ascertain the extension depth of ground fissure since its concealment and uncertainty. In this paper, 3D seismic exploration is used to detect ground fissure in Shanxi Province of China. Specific parameters for seismic data acquisition, processing and interpretation are analysed. Firstly, seismic data acquisition method and its corresponding parameters are discussed. Small dose explosive sources and high frequency geophones are used. Small trace interval and appropriate fold are also adopted. Secondly, seismic data processing is processed from shot record to seismic profile. Multi-domain loop iteration de-noising is used to get high signal-to-noise ratio data. Accurate near surface model, interactive iteration and residual static correction are used to eliminate the impact of low velocity zone and the static correction problem. Large common middle point bin and small velocity analysis interval are used for high accuracy velocity spectrum analysis. The mute parameter of stretching distortion and the migration aperture are researched for shallow ground fissure detection. Thirdly, seismic data interpretation is processed to get ground fissure distribution. Fault enhanced filter is used to improve the signal-to-noise ratio effectively and the chimney cube is used to identify ground fissure automatically. Thus, the specific 3D seismic exploration method used in this paper is suitable for ground fissure detection.Cited as: Shi, S., Liu, Z., Feng, J., Feng, G., Li, M. Using 3D seismic exploration to detect ground fissure. Advances in Geo-Energy Research, 2020, 4(1): 13-19, doi: 10.26804/ager.2020.01.0

Long-term behaviour of twin tunnels in London clay

The assessment of ageing tunnels requires a deeper understanding of the long-term behaviour of twin tunnels, whilst lack of permeability data limits the accuracy of long-term predictions. This thesis therefore investigates long-term twin-tunnel behaviour through finite-element parametric analyses, and provides additional pereability data through laboratory studies. Permeability tests are performed on fissured London Clay, exploring the effect of isotropic stress cycles on the permeability of fissures. A model explaining the permeability–stress relationship is proposed to explain irrecoverable changes observed in fissure permeability, and is formulated mathematically for numerical implementation. Laboratory investigations are performed on grout from the London Underground tunnels, investigating permeability, porosity, microstructure and composition. A deterioration process is proposed to explain observations, consisting of acid attack and leaching. The deterioration had appeared to transform the grout from impermeable to permeable relative to the soil. The change in grout permeability with time would strongly influence long-term movements. The long-term behaviour of single tunnels is investigated in a finite-element parametric study. A new method is formulated to predict long-term horizontal and vertical surface displacements after excavation of a single tunnel, and incorporates an improved measure of relative soil-lining permeability. The study also predicts significant surface movements during the consolidation period, contradicting the lack of further building damage observed in the field. A further parametric study also investigates the long-term behaviour of twin tunnels. Key interaction mechanisms are identified, leading to the postulation of the long-term interaction behaviour under different tunnelling conditions. Long-term interaction is found to be complex and significant, and should be accounted for in numerical simulations.Supported by an EPSRC doctoral training award provided by the Cambridge University Engineering Departmen

Tunnel Engineering

This volume presents a selection of chapters covering a wide range of tunneling engineering topics. The scope was to present reviews of established methods and new approaches in construction practice and in digital technology tools like building information modeling. The book is divided in four sections dealing with geological aspects of tunneling, analysis and design, new challenges in tunnel construction, and tunneling in the digital era. Topics from site investigation and rock mass failure mechanisms, analysis and design approaches, and innovations in tunnel construction through digital tools are covered in 10 chapters. The references provided will be useful for further reading

Instrumented horizontal drilling for tunnelling site investigation

Imperial Users onl

Geotechnical Engineering for the Preservation of Monuments and Historic Sites III

The conservation of monuments and historic sites is one of the most challenging problems facing modern civilization. It involves, in inextricable patterns, factors belonging to different fields (cultural, humanistic, social, technical, economical, administrative) and the requirements of safety and use appear to be (or often are) in conflict with the respect of the integrity of the monuments. The complexity of the topic is such that a shared framework of reference is still lacking among art historians, architects, structural and geotechnical engineers. The complexity of the subject is such that a shared frame of reference is still lacking among art historians, architects, architectural and geotechnical engineers. And while there are exemplary cases of an integral approach to each building element with its static and architectural function, as a material witness to the culture and construction techniques of the original historical period, there are still examples of uncritical reliance on modern technology leading to the substitution from earlier structures to new ones, preserving only the iconic look of the original monument. Geotechnical Engineering for the Preservation of Monuments and Historic Sites III collects the contributions to the eponymous 3rd International ISSMGE TC301 Symposium (Naples, Italy, 22-24 June 2022). The papers cover a wide range of topics, which include: 　 - Principles of conservation, maintenance strategies, case histories - The knowledge: investigations and monitoring - Seismic risk, site effects, soil structure interaction - Effects of urban development and tunnelling on built heritage - Preservation of diffuse heritage: soil instability, subsidence, environmental damages The present volume aims at geotechnical engineers and academics involved in the preservation of monuments and historic sites worldwide

Tunnelling

Tunnelling has become a fragmented process, excessively influenced by lawyers'notions of confrontational contractual bases. This prevents the pooling of skills, essential to the achievement of the promoters' objectives. Tunnelling: Management by Design seeks the reversal of this trend. After a brief historical treatment of selected developments, t

Statistics of mines and mining in the states and territories west of the Rocky Mountains

Statistics of Mining West of the Rocky Mountains. [1424] Indians in New Mexico; Indians in Montana; Indian labor in eastern Nevada; etc

Mobilizing city-regional urbanization: The political economy of transportation and the Production of the metropolis in Chicago and Toronto

Studies of cities and urbanization are confronted with significant theoretical and methodological challenges as the urban question is reposed at the city-regional scale. Normative understandings of city-regions as sites of economic innovation and distinct political actors on the world stage belie the complex processes underlying their production. This has significant implications for social justice and political practice. This dissertation engages the challenges of city-regional urbanization through a critical comparative analysis of urban transportation institutions and infrastructure in the Chicago and Toronto city-regions. Focusing on long-term historical and spatial structures, the study demonstrates how multiscalar political, economic and social processes crystallize in specific urban formations and in tum, how processes of urbanization shape urban governance and practices of everyday life. The dissertation develops three central theoretical innovations. First, it introduces a geographical historical-materialist comparative framework to examine the contingent evolution of city-regional formations in space and across time using a cross-national perspective. Second, it reframes urban transportation as a key realm of political economy inquiry, redressing the limitations of traditional transportation geography and the poststructural approaches which dominate urban infrastructures literature. Third, it incorporates diverse urban, suburban and post-suburban spaces within an overarching theorization of city-regional urbanization as an expression of centripetal and centrifugal forces. Qualitative methods are used to uncover and analyze socially-entangled and geographically-disparate urban relations. The empirical analysis reveals that the prioritization of particular scales of mobility spurs the emergence of new city-regional topologies which do not neatly align with territorially-defined forms of state space. Strategies of regionalization are as likely to open new fissures in city-regional space as they are to fuse collective regional agency. The convergences and divergences witnessed between the Chicago and Toronto city-regions illustrate the place-specific path dependent properties of institutional and infrastructure fixes that highlight the importance of historically and geographically sensitive comparative research. The dissertation's dialectical and comparative contributions open the city-region as a multifaceted, multiscalar and multilayered object of analysis. It concludes by outlining how the study's dialectical approach to city-regional urbanization can inform debates on urban transformation and social change