Assessment of ground conditions with respect to mechanised tunnelling for the construction of the extension of the Athens Metro to the city of Piraeus

2009 ◽  
Vol 68 (1) ◽  
pp. 17-26 ◽  
Author(s):  
P. G. Marinos ◽  
M. Novack ◽  
M. Benissi ◽  
G. Stoumpos ◽  
D. Papouli ◽  
...  
1988 ◽  
Vol 15 (1) ◽  
pp. 91-97 ◽  
Author(s):  
I. C. Goulter ◽  
A. Kazemi

The spatial and temporal patterns of water distribution pipe failure in the City of Winnipeg are examined. The failures are shown to be strongly clustered in space, where 22% of the total failures examined occur within 1 m of another failure and 46% occur within 20 m of another failure. A strong temporal clustering is also apparent, with 42% of all failures that occur within 1 m of another found also to occur within 1 day of the initial failure in the group. An exponential decrease in the marginal rates of failure with respect to both the temporal and spatial interval parameter is also observed. Earlier failures in a particular location appear to be an important key to assessing potential failures in that vicinity. These results suggest that a fruitful area for further examination for the reduction of failure rates is the change in the ground conditions resulting from an initial leak and its subsequent repair. Key words: failures, groupings, marginal rates, pipes, space, time, water distribution, Winnipeg.


2005 ◽  
Vol 21 (1_suppl) ◽  
pp. 125-136 ◽  
Author(s):  
Mohammad Kazem Jafari ◽  
Mohammad Reza Ghayamghamian ◽  
Mohammad Davoodi ◽  
Mohsen Kamalian ◽  
Abdollah Sohrabi-Bidar

The site amplification characteristics of the 2003 Bam, Iran, earthquake were investigated based on geological studies as well as geophysical, microtremor and aftershock measurements conducted by IIEES in the study area. A site effect microzonation map was prepared classifying the ground conditions of the city into five distinct categories, based on their stiffness, thickness, and frequency characteristics. The highest percentage of damage was concentrated in sites with stiff shallow and medium depth soils, which possessed considerable amplification potentials in high frequency ranges.


2013 ◽  
Vol 1 (5) ◽  
pp. 5881-5910 ◽  
Author(s):  
S. V. Samsonov ◽  
P. J. González ◽  
K. F. Tiampo ◽  
N. d'Oreye

Abstract. Fast ground subsidence in southern Saskatchewan (Canada) between the City of Saskatoon and Rice Lake was observed with the RADARSAT-2 Interferometric Synthetic Aperture Radar (InSAR) during 2008–2011. We collected 23 ascending Multi-Look Fine 3 Far (MF3F) and 15 descending Standard 3 (S3) RADARSAT-2 images and performed time series analysis utilizing SBAS and MSBAS methodologies. We observed two well-defined circular regions located a few km apart and subsiding with the nearly constant rate of about 10 cm yr−1. MSBAS decomposition revealed presence of both vertical and horizontal ground displacements. For further analysis we selected two highly coherent interferograms spanning from November–December 2009 until April 2010 that due to particularly favorable ground conditions displayed superior coherence. We performed modeling and inversion assuming spherical and sill source models in order to determine the source location, depth and strength. The smallest residual of about 1 cm yr−1 was achieved with the sill model when both, ascending and descending, interferograms were used. This model suggested sources located at 1.3 and 1.2 km depth with radius of 1.0 and 1.3 km for eastern and western areas, respectively. The spherical model suggested slightly shallower sources located at 0.9 and 0.8 km. We could not precisely identify the cause of this deformation but the observed subsidence rate and source depth suggest mining related origin. Topographic changes produced by this subsidence rate over a long time may produce shallow groundwater redistribution and flooding of agricultural lands.


Author(s):  
В.Б. Заалишвили ◽  
Д.А. Мельков ◽  
В.Д. Макиев

Проявление каждого ощутимого землетрясения несет в себе уникальную информацию о его реальном проявлении на исследуемой территории. Поэтому сбор и анализ всех имеющихся данных о проявлении сейсмически событий на исследуемой территории является важным по оценке сейсмической опасности. В работе рассмотрено проявление наиболее сильного землетрясения, произошедшего в современное время – Рачинского землетрясения 29 апреля 1991 г. на территории г. Амбролаури. Показано усиление сейсмического эффекта, обусловленного влиянием грунтовых условий. Рассмотрено проявление слабого землетрясения 2005 г. на территории г. Владикавказа и выполнено сопоставление с действующей картой сейсмического микрорайонирования. Использование современных информационных технологий позволило по признакам проявления слабых воздействий выделить отдельные участки, в которых сейсмический эффект может быть обусловлен индивидуальными локальными особенностями грунтовых условий, а также спектральными особенностями воздействия и состояния застройки Macroseismic evidence of each significant earthquake carries a unique information about its actual impact on the investigated territory. Therefore, the collection and analysis of all available data on the occurrence of seismic events in the study area is important in assessing seismic hazard. The paper shows the manifestation of the strongest earthquake that occurred in modern times – the Racha earthquake on April 29, 1991 in the territory of Ambrolauri city. The increase in the seismic effect due to the influence of ground conditions is shown. The manifestation of a weak earthquake in 2005 in the territory of the city of Vladikavkaz is considered and a comparison is made with the current seismic microzoning map. The use of modern information technologies made it possible, on the basis of manifestations of weak effects, to single out individual areas in which the seismic effect can be caused by individual local features of ground conditions, as well as the spectral features of the impact and building conditions


2015 ◽  
Vol 94 (4) ◽  
pp. 399-417 ◽  
Author(s):  
J. Schokker ◽  
M.A.J. Bakker ◽  
C.W. Dubelaar ◽  
R.M. Dambrink ◽  
R. Harting

AbstractAmsterdam is situated on the coastal-deltaic plain of the western Netherlands. Its geographical position brought the city prosperity, but also created huge challenges associated with heterogeneous and often adverse ground conditions. This paper explores the geology of Amsterdam to a depth of c. 100 m, based on the output of the 3D geological subsurface models DGM and GeoTOP. The model results are used to create a geological map of the area, to determine the extent and depth of the foundation levels that are in use for buildings in the city centre and to detect the source of filling sand on which part of the more recent expansion of the city was founded. It is shown that subsurface conditions have had a profound effect on both landscape development and historical city growth. Geomodels like DGM and GeoTOP provide an easily accessible way to obtain a better understanding of the shallow subsurface.


2008 ◽  
Vol 8 (4) ◽  
pp. 779-788 ◽  
Author(s):  
D. Raucoules ◽  
I. Parcharidis ◽  
D. Feurer ◽  
F. Novalli ◽  
A. Ferretti ◽  
...  

Abstract. In the present study SAR interferometric techniques (stacking of conventional interferograms and Permanent Scatterers), using images from satellites ERS-1 and 2, have been applied to the region of Thessaloniki (northern Greece). The period covered by the images is 1992–2000. Both techniques gave good quantitative and qualitative results. The interferometric products were used to study ground surface deformation phenomena that could be related to the local tectonic context, the exploitation of underground water and sediments compaction. The city of Thessaloniki shows relatively stable ground conditions. Subsidence in four locations, mainly in the area surrounding the city of Thessaloniki, has been detected and assessed. Two of the sites (Sindos-Kalochori and Langadhas) were already known from previous studies as subsiding areas, using ground base measurements. On the contrary the other two sites in the northern suburbs of Thessaloniki (Oreokastro) and in the south-east (airport area) were unknown as areas of subsidence. A further investigation based on fieldwork is needed in these two areas. Finally, an attempt to interpret the observed deformation, according to the geological regime of the area and its anthropogenic activities, has been carried out.


1999 ◽  
Vol 27 (2) ◽  
pp. 202-203
Author(s):  
Robert Chatham

The Court of Appeals of New York held, in Council of the City of New York u. Giuliani, slip op. 02634, 1999 WL 179257 (N.Y. Mar. 30, 1999), that New York City may not privatize a public city hospital without state statutory authorization. The court found invalid a sublease of a municipal hospital operated by a public benefit corporation to a private, for-profit entity. The court reasoned that the controlling statute prescribed the operation of a municipal hospital as a government function that must be fulfilled by the public benefit corporation as long as it exists, and nothing short of legislative action could put an end to the corporation's existence.In 1969, the New York State legislature enacted the Health and Hospitals Corporation Act (HHCA), establishing the New York City Health and Hospitals Corporation (HHC) as an attempt to improve the New York City public health system. Thirty years later, on a renewed perception that the public health system was once again lacking, the city administration approved a sublease of Coney Island Hospital from HHC to PHS New York, Inc. (PHS), a private, for-profit entity.


ASHA Leader ◽  
2013 ◽  
Vol 18 (7) ◽  
pp. 46-48

This year's Annual Convention features some sweet new twists like ice cream and free wi-fi. But it also draws on a rich history as it returns to Chicago, the city where the association's seeds were planted way back in 1930. Read on through our special convention section for a full flavor of can't-miss events, helpful tips, and speakers who remind why you do what you do.


ASHA Leader ◽  
2017 ◽  
Vol 22 (7) ◽  
Author(s):  
Sean Sweeney
Keyword(s):  

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