Foundation Structure (foundation + structure)

Distribution by Scientific Domains


Selected Abstracts


Accounting for velocity anisotropy in seismic traveltime tomography: a case study from the investigation of the foundations of a Byzantine monumental building

GEOPHYSICAL PROSPECTING, Issue 1 2006
L. Polymenakos
ABSTRACT We estimate velocity anisotropy factors from seismic traveltime tomographic data and apply a correction for anisotropy in the inversion procedure to test possible improvements on the traveltime fit and the quality of the resulting tomographic images. We applied the anisotropy correction on a traveltime data set obtained from the investigation of the foundation structure of a monumental building: a Byzantine church from the 11th century AD, in Athens, Greece. Vertical transverse isotropy is represented by one axis of symmetry and one anisotropy magnitude for the entire tomographic inversion grid. We choose the vertical direction for the symmetry axis by analysing the available data set and taking into account information on the character of the foundations of the church from the literature and past excavations. The anisotropy magnitude is determined by testing a series of values of anisotropy and examining their effect on the tomographic inversion results. The best traveltime fit and image quality are obtained with an anisotropy value (Vmax/Vmin) of 1.6, restricted to the high velocity structures in the subsurface. We believe that this anisotropy value, which is significantly higher than the usual values reported for near-surface geological material, is related to the fabric of the church foundations, due to the shape of the individual stone blocks and the layout of the stonework. Inversion results obtained with the correction for anisotropy indicate that both the traveltime fit and the image quality are improved, providing an enhanced reconstruction of the velocity field, especially for the high-velocity features. Based on this enhanced and more reliable reconstruction of velocity distribution, an improved image of the subsurface material character was made possible. In particular, the pattern and state of the church foundations and possible weak ground material areas were revealed more clearly. This improved subsurface knowledge may assist in a better design of restoration measures for monumental buildings such as Byzantine churches. [source]


Spatial foundation structures over no tension soil

INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 14 2005
A. Baratta
Abstract The problem of the stress distribution induced in the soil by a single circular foundation structure is approached in a three-dimensional analysis. Since the soil is typically made by not-cohesive materials, its behaviour is modelled by means of the not resisting tension (NRT) hypothesis, thus assuming that its very low resistance to tensile stresses can be completely neglected and that it keeps linearly elastic under pure compression. After developing the problem from a theoretical point of view on the basis of an energetic approach, a numerical application,which is able to reproduce the stress distribution induced by a circular foundation on the soil,is performed. Copyright © 2005 John Wiley & Sons, Ltd. [source]


Contribution of geophysics to outlining the foundation structure of the Islamic Museum, Cairo, Egypt

ARCHAEOLOGICAL PROSPECTION, Issue 3 2005
A. M. Abbas
Abstract The Islamic museum was erected in 1896. The building is situated in the heart of Cairo (capital of Egypt) and holds marvellous Islamic antiquities and priceless ancient hand-writing and rare books. Recently, a restoration scheme has been planned to secure the old building which suffers from weakened foundations. In addition, the wooden roofs will be replaced by concrete ones and an extra floor will be integrated into the building. Unfortunately, the architecture construction charts were neither available nor obtainable. Therefore, the structure of the foundations and the base walls of the building had to be outlined. At the time of construction, three major fundamental wall designs were dominant and were to be considered during the work approach. Ground-penetrating radar (GPR) and dipole,dipole resistivity imaging have been integrated to (define the structure of the foundation walls of the building. A Ramac2 system connected to a 500,MHz antenna has been utilized for conducting the GPR survey. In addition, a Terrameter SAS 1000 single channel device has been used for performing the resistivity profiles. At accessible spaces around the building GPR and resistivity profiles were obtained. The GPR analysis has revealed the depth of the foundation walls to be about 0.9,m from the ground surface with a width close to 0.6,m. The wall design is close to a straight wall style. Furthermore, the analysis of the dipole,dipole resistivity measurements has matched the geology of the area, where subsoil anomalies may be due to the scattered limestone blocks that occur in the area. Moreover, the foundation walls have resistivity values that fall into the range of fractured limestone or limestone blocks. A step-wise or inclined foundation wall style has not been indicated through the parallel resistivity profiles. Copyright © 2005 John Wiley & Sons, Ltd. [source]


Spatial foundation structures over no tension soil

INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 14 2005
A. Baratta
Abstract The problem of the stress distribution induced in the soil by a single circular foundation structure is approached in a three-dimensional analysis. Since the soil is typically made by not-cohesive materials, its behaviour is modelled by means of the not resisting tension (NRT) hypothesis, thus assuming that its very low resistance to tensile stresses can be completely neglected and that it keeps linearly elastic under pure compression. After developing the problem from a theoretical point of view on the basis of an energetic approach, a numerical application,which is able to reproduce the stress distribution induced by a circular foundation on the soil,is performed. Copyright © 2005 John Wiley & Sons, Ltd. [source]


Über den Bodendruck erdgelagerter Behälter

BAUTECHNIK, Issue 5 2008
Gustav-Erich Rosemeier Prof. Dr.-Ing.
Es werden Probleme bodengelagerter Behälter behandelt, deren Unterbauten schalenförmig ausgebildet sind. Die physikalischen Bodeneigenschaften sollen dabei denen eines elastischen Halbraums entsprechen, wobei Randkorrekturen bei den Bodenpressungen berücksichtigt werden. The foundation pressure of shells based on the soil (ground tanks). The problem of ground tanks is discussed here, where the foundation structures are shells. The physical dates of the ground shells shall be described by an elastic half-space, whereas some corrective terms of the soil pressure at the boundaries of the tanks are considered. [source]