Keywords: Fondation ; Mur de soutenement ; Pieux ; Capacite portante ; Ancrage ; Dimensionnement Reference Record created on 2004-09-07, modified on 2016-08-08

Two or more strip footings are quite often built close to each other, due to which there will be overlapping of stresses in zones or at points between the footings. There is a non-uniform pressure distribution in the foundation soil beneath the footings, in the space between the footings and beyond. There is also an increase in confining pressure of the soils between the footings. All these result in the tilt of the footings. This numerical study looks into the tilt of the already existing strip footings due to the construction of an adjacent new strip footing on the surface of cohesionless soils. A parametric study is conducted including the effect of geogrid reinforcement/s beneath the new footing. One of the footings representing an already existing foundation is loaded with half of the estimated failure load of a single-strip footing, and adjacent new strip footing is loaded up to failure. The property boundary line is assumed to be midway between the two footings. Geogrid reinforcement layers beneath the new footing are considered to be extending equally beyond the footing on either side, up to the property line. Both unreinforced and reinforced sands are considered beneath the new footing for analyses. Tilts are observed to increase with the width of footing. At closer spacings, tilt was found to be more in case of loose sand. Results of this study indicate that there is a considerable increase in the tilt of the old footing in the presence of reinforcements beneath the new footing.

methods

Foundation analysis and design

Studies on Tilt of Closely Spaced Strip Footings on Unreinforced and Reinforced Sands

Added stresses due to adjacent structure should be considered in foundation design and stress control in soil under the structure. This case is considered less than other cases in design and calculation whereas stresses in implementation are greater than analytical stress. Structure load are transmitted to earth by foundation and role of foundation is propagation of load on the continuous and half extreme soil. This act cause that, present stresses lessen to allowable strength of soil. Some researchers such as Boussinesq and westergaurd by using of some assumption studied on this issue, theorically. Target of this paper is study and evaluation of added stresses under structure due to adjacent structure. For this purpose, by using of assumption, theoric relation and numeral methods, effects of adjacent structure with 4 to 10 storeys on the main structure with 4 storeys are studied and effect of parameters and sensitivity of them are evaluated. Keywords— stress, soil, adjacent structure, foundation, loading.

Study and Evaluation of Added Stresses under Foundation due to Adjacent Structure

In this study, equation of calculating vertical stress increment developing in underneath of the embankmentdue to the extension of embankment width was derived through the use of theory of elasticity. Concept of the originof plane was adopted to simplify derivation procedure for obtaining the equation. Comparing the results of the equation for calculating vertical stress increment with those of the numerical analyses, differences in the magnitudesof vertical stress increments decrease as the depths below embankment increase. Comparing the vertical stress increments with horizontal distances which correspond to certain depth, vertical stress increments obtained from thederived equation were slightly greater than those of numerical analyses. Keywords : Extension of embankment, Vertical stress increment, Origin of plane, Numerical analysis * Corresponding Author : Eung-Seok Kim(Sunmoon Univ.)Tel: +82-41-530-2325 email: hydrokes@sunmoon.ac.kReceived July 10, 2015 Accepted October 8, 2015Revised September 1, 2015Published October 31, 2015

Additional excerpts

Study on the Method of Determination of Vertical Stress Due to Extension of Embankment Width

Experimental Study on Pile Group Efficiency in Various Types of Soil Using a Small–Scale Physical Model

عوـن هـس زا هـلاقم نـيا رد .تـسا کـينکتوئژ يـسدنهم ياـجرب ياـه شيامزآ نـيرت مهم زا يـکي ،يرتمويـسرپ شـيامزآ -هدـیکچ يـبصع هکبـش زا ادـتبا رد .تـسا هدـش هدافتـسا يرتمويـسرپ شـيامزآ جـياتن ريـسفت روـظنم هـب )ANN( يـعونصم يـبصع هکبـش هدافتـسا يعاعـش ياـنبم عـبات يـبصع هکبـش زا ناـياپ رد و هدـش هـتفرگ هرـهب يزاـفورن هکبـش زا هـمادا رد ،نورتپـسرپ هـيلا دـنچ ياه هکبـش فـلتخم ياـه لدم ناـياپ رد .دنا هدـش ليکـشت يـجورخ کـي و يدورو 5 ياراد يـلک راتخاـس زا اـه لدم .تـسا هدـش مـيمعت تردـق يـبايزرا یارـب .تـسا هدـش صخـشم هتـشاد ار درـکلمع نـيرتهب هـک يا هکبـش و هدـش هـسياقم رـگيدکي اـب يـبصع يـنتبم ياـه لدم .تـفرگ رارـق هـسياقم دروـم يـبرجت جـياتن اـب هدـشن هـبرجت ياـه هداد لـباقم رد رـظن دروـم هکبـش درـکلمع ،لدـم ماـجنا اـب شـهوژپ نـيا رد .دـنهد يمن يـجورخ رـب يدورو ياـهرتماراپ رـثا يـگنوگچ دروـم رد يـحيضوت يـبصع ياه هکبـش رـب .دوـش هداد خـساپ لاوـس نـيا هـب يدودـح اـت تـسا هدـش يعـس هدـش يـفرعم لدـم هـنيهب راتخاـس يوررـب تيـساسح زـيلانآ

Foundation analysis and design

Citations

Studies on Tilt of Closely Spaced Strip Footings on Unreinforced and Reinforced Sands

Study and Evaluation of Added Stresses under Foundation due to Adjacent Structure

Study on the Method of Determination of Vertical Stress Due to Extension of Embankment Width

Experimental Study on Pile Group Efficiency in Various Types of Soil Using a Small–Scale Physical Model

Application of artificial neural networks in interpretation of pressuremeter test results

Related Papers (5)

Soil mechanics in engineering practice

Theoretical Soil Mechanics

Pile Foundation Analysis and Design

Principles of Foundation Engineering

Analysis of Ultimate Loads of Shallow Foundations