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) where A is a pore pressure parameter (−). The above expression can be utilized in the current study when the PWP can be calculated during the tests and the angle of initial internal friction of natural, and the mitigated samples are measured. Good

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cement paste, together with evaporation of capillary water, has a great influence on the build-up of high pore pressure, which can result to explosive spalling of concrete. The dehydration analysis of cement paste can be facilitated by the use of

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Low velocity surface layers can significantly increase ground accelerations during earthquakes. When saturated sandy sediments are present, because of pore pressure increase, decrease of soil strength or even liquefaction can occur. Some volume change follows the dissipation of excess pore pressure after the earthquake resulting surface settlements. To determine the liquefaction probability and post-liquefaction settlement is very important for critical facilities e.g. for the site of Paks Nuclear Power Plant, Hungary. Pore pressure increase and so the liquefaction and surface settlements depend on the characteristics of seismic loading and soil parameters. To quantify the extent of these phenomena is rather difficult. Uncertainties arise both from the probabilistic nature of the earthquake loading and from the simplifications of soil models as well. In the paper, the most important semi-empirical and dynamical effective stress methods for liquefaction and post-liquefaction settlement assessment are summarized. Most significant contributors to the uncertainties are highlighted, and particular examples through the investigation of Paks NPP site are given. Finally, a probabilistic procedure is proposed where the uncertainties will be taken into account by applying a logic tree methodology. At the same time, the uncertainties are reduced by the use of site-specific UHRS and stress reduction factors.

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Cone penetration tests are particularly useful to determine several soil parameters and identify the class of the soil. Generally, information on the current soil properties are given from laboratory and in-situ tests, but the stress history, state of consolidation and the lateral stress parameter at rest can also be important.There are several methods to determine the over-consolidation ratio using cone resistance, sleeve friction and pore pressure from cone penetration test. The methods are applicable to several special soils (intact clays and clean quartz soils), but none can handle all types of soils. The results produced by these the methods are very different, so it is important to analyze them.

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The western shoreline of the Danube from Érd to Mohács consists of loess bluffs up to 50 m high. These bluffs can be susceptible to landslides when groundwater conditions weaken the supporting loess. Often this will occur during periods of high rainfall, however morphological, geological and other factors are also important in triggering these movements.

Changes in pore water pressures related to precipitation, confined water levels driven by remote catchments, and river level fluctuations are widely recognized as important factors controlling the loess bank stability. This work aims to determine the interaction of rainfall, river level, drainage and local pumping on the pore pressure regime and stability of the bluffs.

As a first step, a realistic 2-dimensional infiltration and groundwater model was built that reflects the influence of river levels, rainfall patterns, and local pumping. Based on model results, initial and boundary conditions have a strong influence on seasonal pore pressures. Further study will better define those influences on slope stability along the bluffs.

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Abstract

In the context of verification of civil engineering structures stability and determination of sliding surface and safety factor, a careful analysis of several parameters was carried out to guarantee their safety against failure. To quantitatively forecast failure scope, the embankment dam located on Oued Rhiss in the province of Hocemia is chosen as the model of this study. A static stability analysis is performed by using the Slope/W software. A parametric study performed to evaluate the influence of dam's height, the height of water in the reservoir and the length of drains on the safety coefficient and pore pressures. Reliability analysis elaborated by using the Comrel application, and it allows to statistically quantifying the probability of failure by employing the Monte Carlo distribution. Results show that the dam structure has some weak zones and not strong enough as the safety factor is less than one, it is related to structure's parameters and the drainage system.

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. , Lee J. and Park , I. ( 2007 ), Energy-based evaluation of excess pore pressure using damage potential . International Journal of Offshore and Polar Engineering. [6]. M

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. J. Tóth R.F. Millar 1983 Possible effects of erosional changes of the topographic relief on pore pressures at depth Water

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Pollack Periodica
Authors:
Basim Jabbar Abbas
,
Talib K. Q. Alsheakayree
,
Hussain M. Ashour Al Khuzaie
, and
Hussein Kareem Sultan

improvement of effective angle of friction due to the decrease in pore pressure. The interaction between the columns group and the soft soil leads to improve the distribution of the load bearing capacity [ 11 ]. To decrease the maximum vertical displacement

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]; d b is the bit diameter [cm]; F j is the jet impact force, [N]; g p is the pore pressure gradient, [N/m 2 ]; h is the fractional bit tooth wear [%]; ρ c is the equivalent circulating density, [kg/m 3 ]; N is the rotary speed, [rpm]; R is

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