Study on the Blasting Excavation Method of Urban Shallow Tunnel

2014 ◽  
Vol 580-583 ◽  
pp. 1051-1055 ◽  
Author(s):  
Zi Qiang Li ◽  
Zheng Li
Keyword(s):  
Careful Consideration ◽  
Tunnel Construction ◽  
Shallow Tunnel ◽  
Railway Transport ◽  
Residential Areas ◽  
Construction Methods ◽  
Blasting Excavation ◽  
Core Soil ◽  
Shallow Buried Tunnel ◽  
The City

The construction method requires careful consideration in order to reduce impact of tunnel on the surface of the building in the city. It can have great significance in choosing appropriate blasting excavation method for the poor surrounding rock conditions and complicated ground constructions of shallow buried tunnel. This paper combines the Guanhui urban railway transport projects which the shallow buried tunnel through the dense residential areas, research on the influence of CD method and bench method with reserved core soil when use blasting excavation method on the surface buildings by finite element method. The suitability of two kinds of blasting excavation method in the urban shallow tunnels is analyzed and compared, eventually determine the CD method with blasting excavation is more suitable for the urban shallow tunnel construction, it provides reference and suggestion for future similar construction methods that tunnel construction under the city.

scholarly journals Hollow Effect of Ground Vibration Induced by Electronic Detonator in Shallow Tunnel

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Weijie Ding ◽  
Bei Jia ◽  
Dianshu Liu
Keyword(s):  
Field Experiments ◽  
Optimal Parameter ◽  
Ground Vibration ◽  
Dominant Frequency ◽  
Tunnel Construction ◽  
Shallow Tunnel ◽  
Horizontal Distance ◽  
Mode Decomposition ◽  
Blasting Excavation ◽  
Electronic Detonator

Blasting excavation is extensively used in tunnel construction, and the adverse effect of ground vibration induced by blasting on surrounding structures and inhabitants is a critical problem. This study aims to investigate the tunnel hollow effect on triaxial peak particle velocities (PPV) and dominant frequencies induced by electronic detonator. Field experiments were conducted in a shallow tunnel construction site and the ground vibration waveforms were recorded. Variational mode decomposition (VMD) was applied to denoise and correct the zero-drift phenomenon, and the proposed method of selecting the optimal parameter was verified. A series of statistical analyses and tests were performed to evaluate the differences of peak particle velocity and dominant frequency among various monitoring points. The results showed that the hollow effect on Z-axis PPV is significant, and triaxial PPV is also affected when the horizontal distance exceeds 30 m. The hollow effect on dominant frequency could not be identified since the hollow of tunnel is a free face, and the dominant frequency of reflected wave remains unchanged. An augmented factor of 1.229 is determined carefully as the hollow effect factor on PPV. Therefore, blasting vibration induced by electronic detonator of the excavated zone should be attached with greater importance, and hollow effect on PPV should be considered in the blasting design of tunnel excavation.

Perencanaan Sistem Pengurangan Sampah Permukiman Bantaran Sungai Cidurian Kota Bandung

2019 ◽  
Vol 4 (2) ◽  
Author(s):  
Raka Maulana ◽  
Yulianti Pratama ◽  
Lina Apriyanti
Keyword(s):  
Waste Management ◽  
River Basin ◽  
River Flow ◽  
Waste Reduction ◽  
Residential Areas ◽  
Community Based ◽  
Inorganic Waste ◽  
Waste Bank ◽  
The City

<p>Some areas in the city of Bandung is an area that dilitasi by the flow of the river, to prevent the introduction of garbage into the river basin is necessary to note the waste management systems in residential areas along the river. Cidurian river has a length of 24.86 Km along the river flow. Consists of the city of Bandung and Bandung regency. Administrative regions Cidurian River past eight (8) districts, from the region in the District Kiaracondong precisely Village Babakan Babakan Sari and Surabaya populous and the most densely populated. Thus, there should be community-based waste management in the form of a reduction in resources to prevent potential entry of waste into the river basin. Planning waste reduction will be divided into two, namely the reduction of inorganic waste with waste bank then the reduction of organic waste with absorption holes biopori, and bio reactor mini determination of the reduction is determined by the results of the analysis of the sampling covers the composition and garbage, then the result of the measurement characteristics test and analysis results questionnaire.</p>

Spatial Hotspot Analysis of Bucharest’s Urban Heat Island (UHI) Using Modis Data

2018 ◽  
Vol 18 (1) ◽  
pp. 14-22 ◽  
Author(s):  
Georgiana Grigoraș ◽  
Bogdan Urițescu
Keyword(s):  
Surface Temperature ◽  
Air Temperature ◽  
Land Surface Temperature ◽  
Hot Spots ◽  
Land Surface ◽  
Hot Spot ◽  
Monitoring Network ◽  
Residential Areas ◽  
Hotspot Analysis ◽  
The City

Abstract The aim of the study is to find the relationship between the land surface temperature and air temperature and to determine the hot spots in the urban area of Bucharest, the capital of Romania. The analysis was based on images from both moderate-resolution imaging spectroradiometer (MODIS), located on both Terra and Aqua platforms, as well as on data recorded by the four automatic weather stations existing in the endowment of The National Air Quality Monitoring Network, from the summer of 2017. Correlation coefficients between land surface temperature and air temperature were higher at night (0.8-0.87) and slightly lower during the day (0.71-0.77). After the validation of satellite data with in-situ temperature measurements, the hot spots in the metropolitan area of Bucharest were identified using Getis-Ord spatial statistics analysis. It has been achieved that the “very hot” areas are grouped in the center of the city and along the main traffic streets and dense residential areas. During the day the "very hot spots” represent 33.2% of the city's surface, and during the night 31.6%. The area where the mentioned spots persist, falls into the "very hot spot" category both day and night, it represents 27.1% of the city’s surface and it is mainly represented by the city center.

scholarly journals Who should be tested in a pandemic? Ethical considerations

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Sven Ove Hansson ◽  
Gert Helgesson ◽  
Niklas Juth
Keyword(s):  
Legal Status ◽  
Careful Consideration ◽  
Medical Services ◽  
Residential Areas ◽  
Test Quality ◽  
Ethical Considerations ◽  
Scarce Resources ◽  
Direct To Consumer ◽  
Strict Regulation ◽  
Consumer Test

Abstract Background In the initial phase of the Covid-19 pandemic, difficult decisions had to be made on the allocation of testing resources. Similar situations can arise in future pandemics. Therefore, careful consideration of who should be tested is an important part of pandemic preparedness. We focus on four ethical aspects of that problem: how to prioritize scarce testing resources, the regulation of commercial direct-to-consumer test services, testing of unauthorized immigrants, and obligatory testing. Main text The distribution of scarce resources for testing: We emphasize the use of needs-based criteria, but also acknowledge the importance of choosing a testing strategy that contributes efficiently to stopping the overall spread of the disease. Commercial direct-to-consumer test services: Except in cases of acute scarcity, such services will in practice have to be allowed. We propose that they should be subject to regulation that ensures test quality and adequate information to users. Testing of unauthorized immigrants, their children and other people with unclear legal status: Like everyone else, these individuals may be in need of testing, and it is in society’s interest to reach them with testing in order to stop the spread of the disease. A society that offers comprehensive medical services to unauthorized immigrants is in a much better position to reach them in a pandemic than a society that previously excluded them from healthcare. Obligatory testing: While there are often strong reasons for universal testing in residential areas or on workplaces, there are in most cases better ways to achieve testing coverage than to make testing mandatory. Conclusion In summary, we propose (1) decision-making primarily based on needs-based criteria, (2) strict regulation but not prohibition of direct-to-consumer test services, (3) test services offered to unauthorized immigrants, preferably as part of comprehensive medical services, and (4) broad outreach of testing services whenever possible, but in general not obligatory testing.

Continuous Belt Mucking Technology of China Railway Tunnel Construction

2012 ◽  
Vol 268-270 ◽  
pp. 664-672
Author(s):  
Ya Ting Sun ◽  
Zhi Rong Mei ◽  
Jun Wei Zhang
Keyword(s):  
Conservation Policy ◽  
The Other ◽  
Tunnel Construction ◽  
Frozen Ground ◽  
Railway Tunnel ◽  
Scheme Design ◽  
Construction Methods ◽  
Comprehensive Benefit ◽  
Equipment Configuration ◽  
Blasting Method

The conventional mucking system of tunnel construction in China has a series of deficiencies and stubborn problems. Tunnel mucking technologies matched with different tunnel construction methods have been analyzed systematically and the continuous belt mucking methodology which is appropriated with drilling-blasting method was presented. The continuous belt mucking technology includes mucking scheme design and mucking equipment configuration. Compared with the conventional mucking methods, the comprehensive benefit can be fully demonstrated by the new continuous belt mucking system. On the other hand, the predominance on environmental protection of the continuous belt mucking technoloty matches up with the conservation policy. The technology would be widely applied in long tunnels and tunnels embedded in frozen ground and located in bitter cold plateau. The economic benifis and contribution to society of continuous belt mucking technology would be remarkable.

RESTRUCTURING IN RESIDENTIAL AREAS AND TRANSFORMATION OF THE URBAN SPACE OF THE METROPOLIS

2021 ◽  
Vol 93 (1) ◽  
pp. 134-139
Author(s):  
A.A. STEPANENKO ◽  
Keyword(s):  
Economic Growth ◽  
Urban Space ◽  
Building Materials ◽  
Recycling Rate ◽  
Residential Areas ◽  
Construction Waste ◽  
Cycle Economy ◽  
City Population ◽  
Favorable Conditions ◽  
The City

The article considers the developed model of the closed-cycle economy, which, along with economic parameters, takes into account pollution and consumption of building materials suitable for recycling. The model reflects the idea that the economic growth of a society alone cannot maintain or improve the existing quality of the environment, and for this it is necessary to increase the recycling rate. The purpose of the study is to reveal the factors influencing the increase in the level of recycling when introducing efficient and environmentally friendly systems for managing construction waste in megacities. The results of the study will affect the improvement of the quality and standards of life of the city population, the creation of favorable conditions for a safe, healthy and the prosperous life of people while ensuring the economic growth of the city. The process of the managing the growing volume of construction waste is reflected, recycling is emphasized.

SPATIAL STRUCTURE TRANSFORMATION OF THE ULAN-UDE CITY WESTERN AND SOUTHERN SUBURBS

2021 ◽  
Vol 27 (5) ◽  
pp. 99-106
Author(s):  
А. Badmaev ◽  
◽  
В. Sharaldaev ◽  
Keyword(s):  
Spatial Structure ◽  
Road Transport ◽  
Residential Areas ◽  
City Center ◽  
Huge Number ◽  
Non Profit ◽  
Suburban Areas ◽  
Historical Factors ◽  
The Village ◽  
The City

The article analyzes the processes of suburbanization and transformation of the spatial structure of the city of Ulan-Ude. Modern trends in the growth of Western and historical factors of development, due to socio-economic and historical factors of development. In the 1990s-2000s, because of the decline in agriculture and, as a result, the lack of jobs, the rural population began to migrate massively to the Buryat Republic’s capital. However, the prices for houses and apartments in the city center were unbearable for many migrants, so the purchase of land plots and the construction of houses were affordable for many. The estrangement of agricultural lands and their inclusion in residential areas allowed the city of Ulan-Ude and suburban areas to somewhat expand the territory of settlements and create a huge number of GNPP (gardeners non-profit partnership) and DNPP (dacha non-profit partnership). The city and suburban areas were not ready for such a flow and were not able to provide the newly arrived migrants with social, road transport and communal infrastructure. As a result, the city was surrounded by a suburbia almost devoid of any infrastructure. There are some elements of false urbanization or squatter area, which is a type of urbanization in which the urban population rapid growth is not accompanied by a commensurate increase in urban functions. In recent years, the growth rate of suburban settlements has decreased, mainly due to mortgages, which have become more affordable for the population and the growth of multi-storey construction. In addition, the village is slowly depleting the human resources that feed the city and the suburbs. In other words, those who wanted to move to the city have already moved

Socio-political problems of residents of Вishkek residential areas

2021 ◽  
pp. 346-356
Author(s):  
Rita Bobuevna Salmorbekova ◽  
Dilshat Karimova
Keyword(s):  
Soviet Union ◽  
The State ◽  
Residential Areas ◽  
Sociological Study ◽  
Expert Survey ◽  
Education And Health ◽  
The Soviet Union ◽  
Rational Distribution ◽  
Internal Migrants ◽  
The City

The article examines the problems of the population of the residential areas of the city of Bishkek based on the sociological study. An expert survey carried out in four districts of Bishkek is presented. After the collapse of the Soviet Union, more than 50 new residential areas appeared in the city. Naturally, new residential areas do not have sufficient infrastructure for the population to this day. The current situation with internal migrants in Kyrgyzstan violates the regional demographic balance and the rational distribution of the population across the country. The population is moving actively at the interdistrict and interregional levels. As a result, the main influx of internal migrants moves to Bishkek and Chui Region. The problem of researching the state of the new residential areas in Bishkek is relevant for modern Kyrgyzstan. However, the official statistical base does not cover all citizens living in new buildings, since most residents do not have a residence registration in the area. 75–80 % of the population does not have education and health services. In many residential areas, social facilities, roads, and communications have not been built yet, and the infrastructure as a whole is not developed. Ignoring the issue on the part of the state can lead to a social explosion, expressed by protest actions, exacerbation of social and interregional conflicts among residents of the given area. Based on this, it was necessary to conduct an expert survey among the representatives of the municipal territorial authorities of each district. The main problems of residents of the new residential areas were studied as much as possible.

scholarly journals Migrations of city dwellers to suburban areas – the example of the city of Olsztyn

2012 ◽  
Vol 18 (18) ◽  
pp. 117-124 ◽  
Author(s):  
Agnieszka Szczepańska ◽  
Adam Senetra
Keyword(s):  
Spatial Structure ◽  
Precast Concrete ◽  
Residential Areas ◽  
Dominant Group ◽  
Migration Patterns ◽  
Rural Districts ◽  
Concrete Buildings ◽  
Suburban Areas ◽  
The City

AbstractThe migration of city dwellers to suburbs is a commonly observed phenomenon. The growth of residential areas on the fringes of cities is referred to as suburbanisation. In the present study, migration patterns were investigated in rural districts located in the direct vicinity of the administrative boundaries of Olsztyn over a 10-year timespan. Several hundred building plot purchase/sale transactions in the form of notarial deeds were analysed to determine the dwelling place of the buyer. The analysis of the transactions revealed that the dominant group of purchasers were owners of apartments in multi-family precast concrete buildings, located in the city quarter closest to the studied suburbs. Changes in the spatial structure of suburban areas were also noted.

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