Ground Settlement in Urban Structures Exposed to Geo-environmental and Anthropic Hazards: A Case Study for Galati

This paper presents a case history of observed performance of highway embankment over soft marine clay in Wenzhou, China. During the embankment construction, the changes of ground settlement, ground displacement, and lateral displacement of subsoil with the construction time were monitored and analyzed. The monitoring results indicate that the ground settlement and lateral displacement of subsoil account for about 75% in the process of embankment construction. The measured maximum values of ground settlement, ground displacement, and lateral displacement of subsoil are 37.88 mm, 21.50 mm, and 23.56 mm, respectively. After the completion of the embankment construction, the settlement gradually tended to be stable. It is suggested that the monitoring data of settlement and displacement of embankment are smaller than the design requirements, and the embankment stability is also ensured.

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Ground Settlement of High-Permeability Sand Layer Induced by Shield Tunneling: A Case Study under the Guidance of DBN

Geofluids ◽

10.1155/2020/6617468 ◽

2020 ◽

Vol 2020 ◽

pp. 1-26

Author(s):

Cong Zhou ◽

Wei Gao ◽

Shuang Cui ◽

Xiaochun Zhong ◽

Chengjie Hu ◽

...

Keyword(s):

Influencing Factors ◽

Ground Settlement ◽

High Permeability ◽

Shield Tunneling ◽

Factors Affecting ◽

Settlement Prediction ◽

Correlation Degree ◽

Improvement Measures ◽

Cutter Head

During the shield construction of Harbin Subway Line No. 3 Project, the average ground settlement exceeds the warning value. In order to find the cause of settlement and improve it, this paper establishes a settlement prediction model to analyse the potential influencing factors based on the Deep Belief Network (DBN) and calculated the correlation degree between influencing factors and settlement through sensitivity analysis. It was found that the permeability coefficients of layer and cutter head torque are the main factors affecting settlement. Then, corresponding muck improvement measures were made according to the analysis of the layer conditions, which successfully reduced the permeability and shear strength of the muck, thereby controlling the surface settlement value within the warning range. The research results in this paper illustrate the applicability and robustness of DBN in tunnel engineering, and the related research ideas can be applied to other projects.

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Method for Quantifying Supply and Demand of Construction Minerals in Urban Regions—A Case Study of Hanoi and Its Hinterland

Sustainability ◽

10.3390/su12114358 ◽

2020 ◽

Vol 12 (11) ◽

pp. 4358

Author(s):

Georg Schiller ◽

Tamara Bimesmeier ◽

Anh T.V. Pham

Keyword(s):

Urban Areas ◽

Building Materials ◽

Raw Materials ◽

Supply And Demand ◽

Flow Analysis ◽

Material Flow Analysis ◽

Resource Efficiency ◽

Raw Material ◽

Urban Structures

Urbanization is a global trend: Since 2007 more than 50% of the world’s population have been living in urban areas, and rates of urbanization are continuing to rise everywhere. This growth in urbanization has led to an increased demand for natural resources, in particular non-metallic minerals such as stones, sand and clay, which account for one third of the entire flow of materials. Generally, these materials are traded within regional markets. This close geographical link between the demand for building materials in urban areas and the material supply in the hinterland leads to massive interventions in the natural environment and landscape. These urban–rural linkages can be revealed by applying Material Flow Analysis (MFA) to the built environment in order to trace the flows of building materials. The objective of this paper is to present a method for quantifying regional material flows by considering the supply and demand of building materials. This will be applied to the Vietnamese case study area of Hanoi and its hinterland province Hoa Binh. The results indicate a consumption of almost 60% of the construction mineral reserves in total secured by planning in the hinterland province considering a period of 15 years. However, this does not allow for the general conclusion that raw materials are sufficiently available. The sand reservoirs are only sufficient for eight years and clay reserves are used up after four years. This increases the need to exploit further raw material reserves, which are becoming increasingly scarce and results in stronger interventions in nature In order to safeguard the hinterland from the negative impacts of urbanization, a new understanding of resource efficiency is needed—one that acknowledges both resource efficiency in the construction of urban structures and appropriate resource conservation in the provision of the raw materials from the hinterland. This will require the creation of new integrated planning approaches between urban and regional planning authorities. Regional MFA is one way of realising such an approach.

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Correlation between Land Use and Urban Public Transport: Case Study of Zagreb

PROMET - Traffic&Transportation ◽

10.7307/ptt.v26i2.1471 ◽

2014 ◽

Vol 26 (2) ◽

pp. 179-184 ◽

Cited By ~ 2

Author(s):

Gordana Štefančić ◽

Slavko Šarić ◽

Robert Spudić

Keyword(s):

Land Use ◽

Public Transport ◽

Urban Land Use ◽

Theoretical Assumption ◽

Adequate Model ◽

Urban Structures ◽

Analysis And Synthesis ◽

Urban Public Transport ◽

Travelling Time

Investment in the transport system with the aim of fostering attractiveness and land use in urban structures is of great interest for planners and investors. Investment in urban public transport would especially contribute to revitalising distinct city areas. The samples of high population density and diversified area use are organised around accessible means of urban public transport.The main objective of this case study was to find an adequate model for the solution of urban public transport on the location Novi Jelkovec in Zagreb after the construction of a new urban settlement, with the aim to revitalise the peripheral parts of the city. The theoretical assumption on the influence of better organised transport on land use is hereby researched through the example of correction of timetables and reduction of travelling time between nodes on the line in the Novi Jelkovec settlement. In preparing this paper the following methods were used: analysis and synthesis, mathematical and statistical methods, methods of interviewing. The theory of correlation of land use and urban public transport is based on models that develop the “compact city”. The obtained research results confirm the significance of the correlation between urban land use and urban public transport. It can be concluded that this paper proves the influence of the correlation between land use and urban public transport on the concrete example of Novi Jelkovec. Its implementation could result in solving the concrete traffic problem and along with it a faster urbanisation of the new settlement.

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Anthropogenic Stressors in Upland Rivers: Aquatic Macrophyte Responses. A Case Study from Bulgaria

Plants ◽

10.3390/plants10122708 ◽

2021 ◽

Vol 10 (12) ◽

pp. 2708

Author(s):

Gana Gecheva ◽

Karin Pall ◽

Milcho Todorov ◽

Ivan Traykov ◽

Nikolina Gribacheva ◽

...

Keyword(s):

Plant Communities ◽

Vascular Plants ◽

Aquatic Macrophytes ◽

Aquatic Macrophyte ◽

Base Flow ◽

Urban Structures ◽

Anthropogenic Stressors ◽

Biological Responses ◽

Riparian Habitats

Upland rivers across Europe still exhibit undisturbed conditions and represent a treasure that we cannot afford to lose. We hypothesize that the combination of pristine and modified conditions could demonstrate biological responses along the stressor gradients. Thus, the response of aquatic macrophyte communities to anthropogenic stressors along upland rivers in Bulgaria was studied. Six stressors were selected out of 36 parameters grouped into hydromorphological, chemical variables and combined drivers (catchment land use). The stressors strongly affected species richness on the basis of biological type (bryophytes vs. vascular plants) and ecomorphological type (hydrophytes vs. helophytes). Hydrological alteration expressed by the change of the river’s base flow and altered riparian habitats has led to a suppression of bryophytes and a dominance of riverbank plant communities. Seventy-five percent of mountain sites were lacking bryophytes, and the vegetation at semi-mountainous sites was dominated by vascular plants. It can be concluded that hydropeaking, organic and inorganic pollution, and discontinuous urban structures caused important modifications in the aquatic macrophyte assemblages. Macrophyte abundance and the biological and ecomorphological type of aquatic macrophytes reflect multi-stressor effects in upland rivers.

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The dynamics of population distributions in cities based on daily mobile phone operations: A case study of some Moravian cities

Moravian Geographical Reports ◽

10.2478/mgr-2021-0006 ◽

2021 ◽

Vol 29 (1) ◽

pp. 71-86

Author(s):

Gabriel Kopáčik ◽

Antonín Vaishar ◽

Eva Šimara

Keyword(s):

Mobile Phone ◽

Urban Areas ◽

Urban Structure ◽

Residential Areas ◽

Urban Structures ◽

Population Distributions ◽

Dynamics Of Population ◽

The City ◽

Permanent Residents

Abstract Analyses of the changes in the presence of persons in different central and residential parts of urban areas are subject to evaluation in this paper. Case studies of the cities of Brno, Ostrava and Zlín during the day and night are highlighted. Data from a provider of mobile phone services were used for the analyses. It appears that the data can be important for the comparison of different urban structures. The results demonstrate that the organisation of urban structure affects the number of visitors and thus the area attractiveness. It was confirmed that the number of mobile phone users in the city cores is higher than the number of permanent residents. The greatest differences between the day and night in the city cores were found in Brno, a concentric city with the most important central functions among the cities studied. Differences between the day and night in residential areas were not as large as expected. City neighbourhoods in Brno showed some specific rhythmicity.

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Monitoring Data Analysis and Structural Reliability of Foundation Pit During Construction: A Case Study

10.21203/rs.3.rs-877543/v1 ◽

2021 ◽

Author(s):

Guowang Meng ◽

Hongbin Qiu ◽

Yajie ZHao ◽

Bo Wu ◽

Da Gao ◽

...

Keyword(s):

Structural Reliability ◽

Evaluation Method ◽

Side Wall ◽

Reliability Evaluation ◽

Effective Solution ◽

Ground Settlement ◽

Foundation Pit ◽

Structure Deformation ◽

Reliability Level

Abstract In order to solve the problem that only considering the deformation of the side wall or the ground settlement of a single factor of the reliability evaluation may lead to insecurity, a deformation reliability evaluation method considering both the deformation of the side wall and the ground settlement is proposed. This evaluation method is used to evaluate the reliability of foundation pit structure deformation of Jinan metro in Shandong Province, China. Through the study of the deformation of the side wall and ground settlement loss on six profiles, the influence of the coefficient (λ、α and β) on the reliability is considered, and the recommended value of the coefficient (λ、α and β) is given. The reliability of six profiles is evaluated and the reliability level is obtained successfully. The reliability evaluation method can solve the problem that considering a single failure mode may lead to insecurity, and can provide an effective solution to the reliability evaluation of foundation pit retaining structure deformation.

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ON IMPLEMENTATION AND PERFORMANCE OF AN ANISOTROPIC CONSTITUTIVE MODEL FOR CLAYS

International Journal of Computational Methods ◽

10.1142/s0219876213420097 ◽

2014 ◽

Vol 11 (02) ◽

pp. 1342009 ◽

Cited By ~ 2

Author(s):

MAJID T. MANZARI ◽

KARMA YONTEN

Keyword(s):

Constitutive Model ◽

Pore Pressure ◽

Field Measurements ◽

Ground Settlement ◽

Element Analysis ◽

Foundation Soil ◽

And Performance ◽

Fully Coupled ◽

Anisotropic Constitutive Model

Numerical implementation of an anisotropic constitutive model for clays (SANICLAY) is presented. Moreover, a case study in which a soil embankment is placed on a K0-consolidated over-consolidated clay is analyzed by conducting an elastoplastic fully-coupled finite element analysis. It is shown that anisotropy has significant impact on the ground settlement caused by the placement of soil embankment and on the pore pressure generation and dissipation within the foundation soil. The simulations using SANICLAY favorably compare with the field measurements of ground settlement and pore pressure. The drawbacks of the use of an isotropic elastoplastic model (Cam Clay) are also demonstrated.

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Semianalytical Solution and Parameters Sensitivity Analysis of Shallow Shield Tunneling-Induced Ground Settlement

Advances in Materials Science and Engineering ◽

10.1155/2017/3748658 ◽

2017 ◽

Vol 2017 ◽

pp. 1-8

Author(s):

Jifeng Liu ◽

Huizhi Zhang

Keyword(s):

Stress Field ◽

Influence Factors ◽

Analytic Solutions ◽

Ground Settlement ◽

Shield Tunneling ◽

Circular Tunnel ◽

Factors Analysis ◽

Nonuniform Stress Field

The influence of boundary soil properties on tunneling-induced ground settlement is generally not considered in current analytic solutions, and the hypothesis of equal initial stress in vertical and horizontal makes the application of the above solutions limited. Based on the homogeneous half-plane hypothesis, by defining the boundary condition according to the ground loss pattern in shallow tunnel, and with the use of Mohr-Coulomb plastic yielding criteria and classic Lame and Kiersch elastic equations by separating the nonuniform stress field to uniform and single-direction stress field, a semiempirical solution for ground settlement induced by single shallow circular tunnel is presented and sensitivity to the ground parameters is analyzed. The methods of settlement control are offered by influence factors analysis of semiempirical solution. A case study in Beijing Metro tunnel shows that the semiempirical solution agrees well with the in situ measured results.

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