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Three-dimensional finite element analysis for soil slopes stabilization using piles I-Hsuan Ho ABSTRACT This paper presents the analytical methods of slope-stabilising piles using the three-dimensional (3-D) finite element (FE) analysis with the strength reduction method (SRM). This 3-D FE model is employed to overcome the limitations observed in two-dimensional (2-D) FE analysis. The solutions obtained from 3-D FE analyses are verified to be less conservative in this paper. The 3-D analysis is considered to be of particular importance to pile-slope problems. The soil that flows between piles cannot be taken account properly in the 2-D FE analysis. The method adopted in this paper can avoid the assumption of soil movement and the pressure distribution along the piles subjected to soil movement. The numerical analysis employs the Mohr–Coulomb failure criterion with the strength reduction technique for soil and an elastic member for piles. The spacing effect of the pile is considered in the 3- D model, the S/D (S: centre to centre, ? diameter of pile) ratio, equal to 4.0, is found to be equivalent to the single pile stabilisation. The middle portion of the slope is identified as the optimal location to place the piles. The proper length of the pile, which can be used to stabilise the slope, is also examined using 3-D FE analyses. It is concluded that L/H greater or equal 0.70 is recommended (L: pile length, H: slope height). The numerical analyses are conducted based on a coupled analysis, which simultaneously considers both the slope stability and the pile response. The failure mechanisms of the pile-slope system subjected to the pile locations, pile head conditions and pile length are each discussed. The contact pressure, shear force and moment along the piles are presented to illustrate the pile stabilising mechanism herein. منبع @Civilbest_تحلیل_المان_محدود_شیب.pdf

Lateral Earth Pressure on Lagging in Soldier Pile Wall Systems Howard A. Perko, Ph.D, P.E., CTL|Thompson, Fort Collins, CO, USA hperko@ctlthompson.com John J Boulden, SGM, Inc., Grand Junction, CO johnb@sgm-inc.com Soldier pile and lagging is a conventional means of temporary excavation shoring. Timber lagging design has traditionally been based upon the designer’s experience or empirical rules. One such method is the Goldberg Zoino chart used by the Federal Highway Administration. Most of these methods restrict the designer to a consistent soil profile, certain pile spacing, construction grade timber lagging, and limited depth. The methods do not take into account surcharge loads or a variety of other factors that could arise. A designer working outside of ordinary circumstances with unusual loads, varying soil conditions, or alternate lagging materials has difficulty estimating lateral earth pressures. In rigid earth retention systems, lateral earth pressure is generally assumed to be constant along the length of the wall. In soldier pile and lagging systems, the lagging is often considerably less stiff than the steel soldier piles. As the lagging deflects, the soil tends to bridge between the stiffer elements resulting in a lower pressure on the lagging. Several previously published methods by others for determining this reduced pressure are summarized and discussed. These methods typically consist of using a portion of the active earth pressure in several different pressure distributions. A simple theoretical model is presented for determination of lateral earth pressures on wood lagging. The model is based on a three-dimensional “silo” shaped sliding wedge analysis. Results of the model are compared with other published methods. The model compares well with these methods which cover the normal spectrum of design situations. In addition, the model can be used to estimate lateral earth pressures outside typical situations. منبع Article 6 v4.pdf

FRP composite piles - Applications & Durability Considerations شمعهای مرکب FRP کاربردها و ملاحظات فایل پی دی اف به زبان انگلیسی در 44 اسلاید منبع bridge-14frppileapplication.pdf

ساخت و اجرای شمعهای کوبیدنی ( Driven Piles ) فایل پی دی اف در 52 اسلاید منبع دانلود Driven Pileswww.icivil.ir.zip