Book•
Foundation analysis and design
01 Jan 1968-
TL;DR: In this paper, Fondation de soutenagement et al. presented a reference record for Dimensionnement Reference Record created on 2004-09-07, modified on 2016-08-08.
Abstract: Keywords: Fondation ; Mur de soutenement ; Pieux ; Capacite portante ; Ancrage ; Dimensionnement Reference Record created on 2004-09-07, modified on 2016-08-08
Citations
More filters
01 Jan 2008
7 citations
Cites background or methods from "Foundation analysis and design"
...This method of determining the angle of internal friction was determined by correlating the SPT value obtained during the soil exploration and using (Bowles, 1996) table for empirical values....
[...]
...According to Bowles (1996) “A cast-in-place pile is formed by drilling a hole in the ground and filling it with concrete....
[...]
TL;DR: In this article, the authors investigated the influence of placement conditions on various clays and demonstrated that the swelling of a particular clay type should not be predicted using information and trends obtained for other clays with different origins.
Abstract: The swelling of clay when it is subjected to moisture increase is a complicated process found to be influenced by several factors. The clay’s level of response is highly dependent on its mineralogical composition and structure. Practicing geotechnical engineers use the placement state and general index properties to forecast the swelling behavior of the soils. The purpose of this study was to investigate the influence of placement conditions on various clays and to demonstrate that the swelling of a particular clay type should not be predicted using information and trends obtained for other clays with different origins. Clay from Saudi Arabia was used to investigate the influence of initial moisture content and initial dry density on swelling. The prediction models created by other researchers were compared to the measured values in this study. The swelling behavior of both initially dry and wet prepared bentonite was examined, and the rate at which swelling developed in the bentonite clay was studied. The role of clay content in the volume change of sand–bentonite mixtures was also investigated. It was concluded that the prediction of clay-swelling parameters should not be based on the properties of other clays with different origins and mineralogical compositions. The trends published in the literature should be taken as a general guide only, and the influence of moisture content and dry density on swelling should be verified for individual sites. Because clay content significantly influences the overall volume change, it should be carefully assessed in each case.
7 citations
TL;DR: In this article, a finite element (FE) model of the tree response to static loading was developed, and the interaction between the stem and root-plate stiffness was analysed on three levels: longitudinal stem strains, root plate inclinations and stem deflection curve.
7 citations
TL;DR: In this article, the authors reviewed the progress and state-of-the-art relevant to footing interference investigations and applications and concluded that in general case, apart from well-known factors the footing interference effect depends on embedment depth, width and shape of footings, spacing between footings and differential load intensity on the footings.
Abstract: In practice, footings may be constructed near each other which results in an interaction between foundations and leads to significant effect on bearing capacity (BC), failure mechanism, footing settlement and tilting. This paper reviews comprehensively the progress and state-of-the-art relevant to footing interference investigations and applications. This review covers experimental and theoretical (analytical, numerical and statistical) and field studies which have been performed on the footing interference effects under static and seismic loads defining the variation of efficiency factor (ζ) and its influence on the BC, settlement and tilting of supported structures. The present study reveals the role of current research situation, existing deficiencies and future outlooks on the interfering footings. From the results of past findings and using optimization and statistical algorithm, some relationships for different cases are recommended to estimate the efficiency factor and extending classical equations for practical design. It has been concluded that in general case, apart from well-known factors the footing interference effect depends on embedment depth, width and shape of footings, spacing between footings, and differential load intensity on the footings.
7 citations
Dissertation•
01 Mar 2013
TL;DR: In this paper, a parametric study was carried out to evaluate the impact of change in backfill soil parameters and change in the season of construction on the earth pressures developed behind the abutment.
Abstract: Integral bridges are generally considered an attractive alternative to conventional bridges presenting the economic advantage of lower construction and maintenance costs. However, the concept of the integral bridge presents other challenges primarily arising from the monolithic connection that exists between the superstructure and the substructure. Thermal loading leads to daily cycles of expansion and contraction superimposed on seasonal cycles. This results in significantly higher soil-structure interaction activity that may lead to excessive earth pressures behind the abutment and potential failure of the soil and structure. A parametric study was carried out to evaluate the impact of change in the backfill soil
parameters and change in the season of construction on the earth pressures developed behind the abutment. The frequency of the daily and seasonal cycles of expansion and
contraction is such that granular soils respond as fully drained materials. This is seldom the case for fine grained soils. Excess pore pressures are developed and some drainage may occur. However, data and resource limitations make it not feasible to accurately model this over the long term. Further the need to make assumptions about the temperature cycles and the permeability characteristics weakens the strength of the analysis. Therefore, an
envelope of earth pressure generation was created in these parametric studies by modelling fine grained soils as fully drained and fully undrained. Plaxis 2D was used to model the
bridge and surrounding soil. In developing a realistic model of an integral bridge, the first stage was to simulate a constructed instrumented integral bridge which presented measured values of temperature, deformation and earth pressures in time. This allowed the model to be validated and the sensitivity of the analysis to the parameters assessed. A second simulation was undertaken
to compare the output of an integral bridge analysis using Plaxis 2D finite element software with a published study output carried out using the finite difference method.
There were a number of challenges to overcome in modelling an integral bridge. These are described in some detail, highlighting the impact the assumptions made within this studies, had upon the output. It was found that the backfill stiffness parameter was the dominant factor that controlled the magnitude of earth pressure. The parametric study revealed that the season of construction affected the earth pressures generated behind the abutment with autumn and summer construction often leading to cumulatively lower earth pressures than spring and winter respectively. In integral bridge construction, it is common to use granular soils in backfill construction. However, the use of granular soils in foundation construction may not be sustainable as a result of material availability and construction cost. Fine grained soils are alternatively used
where granular soils are not. It was found that modelling fine grained foundation soils as fully drained and fully undrained produced significant variations in the behaviour of the backfill soil and the resulting earth pressure pattern. It is therefore necessary to take into account the impact of thermal loading on the envelope of earth pressure to ensure that the capacity of the structure and soils are not exceeded or underutilised.
7 citations