Showing papers on "Lateral earth pressure published in 2001"
TL;DR: In this paper, the results of an undrained passive pressure load test in stiff sandy silt and a well-graded gravel are compared with passive pressures computed using the methods discussed.
Abstract: The magnitude of the passive earth pressure that resists the movement of a structure is controlled by the amount the structure moves and the direction in which it moves, strength and stiffness of the soil that resists its movement, friction or adhesion on the interface between the structure and soil, and shape of the structure. The Log Spiral Theory, corrected for 3D effects, provides an accurate means of computing ultimate passive pressures. A hyperbolic expression, together with estimated values of soil modulus and ultimate resistance, provides a means of estimating the relationship between structural movement and passive resistance. It is essential that the soil strength and stiffness used in making these estimates should be appropriate for the soil and the drainage conditions involved. The results of an undrained passive pressure load test in stiff sandy silt and a drained passive pressure load test in well-graded gravel are compared with passive pressures computed using the methods discussed. Reasonable agreement between the calculated and measured values shows that the Log Spiral Theory, corrected for 3D effects, and the hyperbolic load-deflection relationship provide an adequate means of estimating passive resistance for a wide range of conditions.
202 citations
TL;DR: In this paper, an extensive series of centrifuge tests has been performed to evaluate the use of flexible subminiature pressure cells in the centrifuge environment and their subsequent use to measure lateral earth pressures behind retaining walls of narrow backfill width.
Abstract: Arching theory predicts a significant reduction in earth pressures behind retaining walls of narrow backfill width. An extensive series of centrifuge tests has been performed to evaluate the use of flexible subminiature pressure cells in the centrifuge environment and their subsequent use to measure lateral earth pressures behind retaining walls of narrow backfill width. Although the flexible earth pressure cells exhibit hysteresis and nonlinear calibration behaviour, the extensive calibration studies indicate that stiff diaphragm type earth pressure cells may be used with replicate models to measure earth pressures. Measurements of lateral pressures acting on the unyielding model retaining walls show good agreement with Janssen's arching theory. Tests on backfills bounded by vertical planes of dissimilar frictional characteristics indicate arching theory with an average interface friction angle provides a reasonable estimate of lateral earth pressures.Key words: fascia retaining walls, silos, earth press...
156 citations
TL;DR: In this article, the authors give a perspective of the evolution of retaining walls in general, and follow with results of a recent cost survey, showing that geosynthetic reinforced walls are the least expensive of all wall categories and at all wall heights.
128 citations
TL;DR: In this article, the performance of several modular-block reinforced soil retaining walls and reinforced slopes at the vicinity of the fault was evaluated and the failure cases were highlighted and the cause of failure was identified.
125 citations
TL;DR: By taking the failure surface as a combination of the arc of a logarithmic spiral and a straight line, passive earth pressure coefficients in the presence of a horizontal pseudostatic earthquake body were derived in this article.
Abstract: By taking the failure surface as a combination of the arc of a logarithmic spiral and a straight line, passive earth pressure coefficients in the presence of horizontal pseudostatic earthquake body...
103 citations
TL;DR: In this paper, a 3D coupled boundary element approach was employed to analyze the response of vertical piles subjected to passive loadings, such as soil shrink/swelling, soil surface surcharge, tunnelling, and cavity formation in soil.
68 citations
TL;DR: A 17 m-high steel strip reinforced soil retaining wall was instrumented to compare field measurements with predictions given by the design guidelines of the American Association of State Highway and Transportation Officials (AASHTO) 1996 Standard Specifications and the AASHO 1999 Interim Revisions.
Abstract: A 17 m-high steel strip reinforced soil retaining wall was instrumented to compare field measurements with predictions given by the design guidelines of the American Association of State Highway and Transportation Officials (AASHTO) 1996 Standard Specifications and the AASHTO 1999 Interim Revisions. The AASHTO models were conservative with respect to external lateral earth pressures and lateral earth pressures on the facing panels. On average, the AASHTO 1996 and 1999 models overestimated lateral pressure at the facing by 94 and 142%, respectively. Measured values of foundation bearing stress were generally in good agreement with values calculated using soil unit weight and depth, except that the average force from the facing panels on the leveling pad was twice that of the weight of the panels themselves. This discrepancy is attributed to shear stress on the back of the facing panels and vertical loads transferred to the panels through the strip connection clips. The location of the zone of maximum strip...
52 citations
TL;DR: In this paper, a series of centrifuge tests were conducted to investigate the seismic behavior of fixed-base, cantilever, retaining walls supporting saturated, liquefiable, cohesionless backfills.
Abstract: A series of centrifuge tests were conducted to investigate the seismic behavior of fixed-base, cantilever, retaining walls supporting saturated, liquefiable, cohesionless backfills. Accelerations, bending strains, deflections, and lateral earth pressures were measured on the walls. Accelerations, pore pressures, and surface settlements were measured in the soil. Parametric studies investigating effects of wall stiffness and magnitude of shaking on the wall-soil behavior were conducted. The magnitude and distribution of lateral earth pressures were determined. Experimental results demonstrated that excess pore pressures in liquefiable backfills contribute significantly to seismic, lateral, earth pressures. It was shown that the average rise in the dynamic thrust is well correlated to the excess pore pressures in the backfill but is insensitive to the range of wall stiffness. It was found that simple calculations, based on Coulomb's active earth pressure theory, can be used to estimate the dynamic thrust at...
49 citations
TL;DR: In this article, a wall consisting of anchored steel piles with horizontal timber laggings was selected to support a 16 m deep excavation with a length of more than three kilometres near Cologne in Germany.
33 citations
Journal Article•
TL;DR: In this paper, the results of analyses on the behavior of in situ walls, using the measured data collected from various deep excavation sites with multilayered ground conditions of soils overlying rock in Korea, were presented.
Abstract: This paper presents the results of analyses on the behavior of in situ walls, using the measured data collected from various deep excavation sites with multilayered ground conditions of soils overlying rock in Korea. A variety of in situ wall systems from .60 excavation sites were considered, covering a wide range of wall types, including H-pile, soil cement, cast in place pile, and diaphragm. The measured data were thoroughly analyzed to investigate the effects of wall and support types on lateral wall movements as well as apparent earth pressures. A series of 2D finite element analyses were also performed to provide insights regarding the in situ wall behavior. Based on the results, lateral wall movements and apparent earth pressures are related to primary influencing factors affecting the wall behavior and information is presented in forms to provide tools that can be used for design and analysis.
31 citations
TL;DR: In this paper, the authors compared the passive earth pressure coefficients given by the author with those obtained on the basis of the limit equilibrium technique by employing the composite logarithmic spiral failure surface both for the static (Kumar and Subba Rao 1997) and the pseudo-static cases.
Abstract: The author needs to be commended for his computational efforts in determining the passive earth pressure coefficients for both the static case as well as in the presence of pseudostatic earthquake forces. The upper bound theorem of limit analysis with the use of a kinematically admissible translational failure mechanism was formed as the basis for solving the problem. In this discussion, the passive earth pressure coefficients given by the author have been compared with those obtained on the basis of the limit equilibrium technique by employing the composite logarithmic spiral failure surface both for the static (Kumar and Subba Rao 1997) and the pseudo-static cases (Kumar 2001). The comparison of all of the results is given in Tables D1 and D2. The two approaches compare well with each other. The passive earth pressure coefficients generated on the basis of the upper bound limit analysis in most of the cases are found to be either almost the same or only marginally greater (for larger values of d) than those computed with the limit equilibrium approach. However, compared to the limit equilibrium technique, the limit analysis has an obvious advantage
TL;DR: In this article, the strut monitoring results were compared with the apparent earth pressure envelopes recommended by Peck, and it was concluded that the measured earth pressures relate reasonably well to the expected earth pressure envelope.
TL;DR: In this article, a series of experimental tests are conducted in a prefabricated large-scale drag box with dimensions 1.83 m 3 1.22 m, where model pipes 0.61 m long with diameters of 152.4, 228.6, and 304.8 mm are obliquely moved from an axial-longitudinal to lateral transversal direction in the drag box to study the associated soil restraints of the oblique pipes with various shallow embedded depths.
Abstract: This paper presents the soil friction restraint on oblique pipelines in loose sand. A series of experimental tests are conducted in a prefabricated large-scale drag box with dimensions 1.83 m 3 1.83 m 3 1.22 m. Model pipes 0.61 m long with diameters of 152.4, 228.6, and 304.8 mm are obliquely moved from an axial-longitudinal to lateral-transversal direction in the drag box to study the associated soil restraints of the oblique pipes with various shallow embedded depths. All the test results indicate that for the axial pipes, the longitudinal soil restraint could be estimated as the product of the average of the vertical and horizontal earth pressures at the centerline of the pipe and the tangent value of soil-pipe friction angle, whereas for the lateral pipes, the transversal soil restraint could be predicted by using the limit equilibrium model with the assumption of the planar sliding failure surface. The longitudinal and transversal soil restraints of the oblique pipes could geometrically be obtained by multiplying the corresponding cosine and sine values of the oblique angle with the associated longitudinal soil restraint of axial pipe and the transversal soil restraint of the lateral pipe, re- spectively. The findings also indicate that the scale effects are not significant for the size of the pipes tested herein.
TL;DR: In this paper, the vertical soil pressure measurements made in the Ohio University field study were compared with the predictions made by the elastic solutions, which showed that the zone of pipe-soil interaction may be confined to one to two pipe diameters from the pipe.
Abstract: When a flexible pipe is installed in a dense soil fill, stress redistribution takes place around the pipe because of pipe-soil interaction. The degree of this interaction is considered to be influenced by the stiffness ratio between the pipe and its surrounding soil. Classical theory based on elastic solutions shows that in an ideal installation condition, the zone of the pipe-soil interaction may be confined to one to two pipe diameters from the pipe. In 1999 a research team from the Ohio Research Institute for Transportation and Environment installed a total of 18 instrumented thermoplastic pipes at the deep pipe burial project site in Albany, Ohio. These pipes were placed under either a 6.1-m or 12.2-m (20-ft or 40-ft) embankment fill. During the pipe backfilling and subsequent embankment fill placement, soil pressure cells were placed at different fill heights above selected test pipes to measure the vertical extent of the pipe-soil interaction zone. The field-measured vertical soil pressure compared well with the predictions made by the elastic solutions. Summarized here are the information and data related to the vertical soil pressure measurements made in the Ohio University field study.
TL;DR: In this paper, a large excavated rectangular pile (barette) with lateral earth pressure and pore-water pressure cells was successfully constructed and tested in a sequence of marine, alluvial, and weathered granite soils.
Abstract: Over the last 15 years, barette foundations have become increasingly popular in parts of Asia, such as Hong Kong and Malaysia, for many civil engineering structures and tall buildings. A large excavated rectangular pile (barette) with lateral earth pressure and pore-water pressure cells was successfully constructed and tested in a sequence of marine, alluvial, and weathered granite soils. A soft base formed beneath the bottom of the barette permitted over 100 mm of vertical settlement, completely mobilizing the shaft friction at the barette-soil interface. During the vertical load tests, an unusual and complex response of pore-water pressures and earth pressures at the barrette-soil interface was measured. During each vertical loading cycle (except the last one) and before interface slippage of the barrette occurred, excess positive pore-water pressures were recorded in all soil layers. Upon the initiation of slip at the barrette-soil interface, a sudden drop in the measured pore pressures as well as a substantial drop in lateral earth pressures generally resulted. Subsequent loading and unloading slippage events did not show the same dramatic behavior unless a period of consolidation/recovery was allowed first. This implies that caution must be used in design of barrettes relying heavily on skin friction when shearing induces contractive soil behavior. The current test results indicated that the empirical uncorrected N-value measured by Standard Penetration Tests (SPT-N approach) and the deduced shaft friction coefficient (beta) value based on the effective stress principle (effective stress beta-method) were inconsistent.
TL;DR: In this article, a new method of solving earth pressure problems is proposed within the framework of the limit equilibrium approach, where the concept of the critical slip field (CSF) is introduced.
Abstract: A new method of solving earth pressure problems is proposed in this paper within the framework of the limit equilibrium approach. The concept of the critical slip field (CSF) is postulated: the act...
TL;DR: In this article, the lateral earth pressures acting against a small-scale retaining wall, with a backfill consisting of waste foundry sand (WFS) mixtures, were analyzed.
Abstract: This paper presents experimental data concerning the lateral earth pressures acting against a small-scale retaining wall, with a backfill consisting of waste foundry sand (WFS) mixtures. The instrumented retaining-wall facility at Dongeui College in Korea was used in the testing. Two different testing methods were employed in this study: the controlled-strain method and the natural-strain method. The lateral earth pressures on the wall depend on the backfilling sequence, the type and drainage characteristic of the WFS mixture, and the shear strength of the mixtures. The mixtures of Green WFS performed best, showing a decrease in the lateral earth pressures and an increase in cohesion with curing time. The measured thrust lateral earth pressure of WFS mixtures was less than that observed for common residual soils in Korea. The stability of the retaining wall with respect to overturning and sliding, calculated using the measured lateral earth pressures, increased substantially with curing time. Judging from the retaining wall model test, the backfilling of a 6-m high retaining wall can be completed in two days with two backfilling stages.
TL;DR: In this paper, the effects of soil yielding on the internal pile response during earthquakes are examined. But the authors do not consider the impact of the soil-pile interface on the seismic analysis of pile foundations.
01 Jan 2001
TL;DR: For many years engineering practice for earth retaining structures emphasized earth pressures and their application in choosing an appropriate design and support system as discussed by the authors, and there has been an increasing use of reinforcing elements, either by incremental burial to create reinforced soils or by systematic in situ installation to produce soil nailing.
Abstract: For many years engineering practice for earth retaining structures emphasized earth pressures and their application in choosing an appropriate design and support system. In the last 25 years there has been a dramatic growth in new construction technologies and products for retaining soil. In particular there has been increasing use of reinforcing elements, either by incremental burial to create reinforced soils or by systematic in situ installation to produce soil nailing. Rapid developments in polymer manufacturing have led to a wide range of polymeric products (geosyn-thetics) (see Chapter 7). These materials are now routinely used to reinforce the soil in retaining wall and slope applications, and to control soil drainage. Reinforced soils and soil nailing have changed the ways built-up and in situ walls are constructed by providing economically attractive alternatives to conventional methods. The use of these products in reinforced soil applications has led to many different earth retention systems.
TL;DR: In this article, an earth pressure cell (EPC) is designed to provide an estimate of normal stress in soil, and a scheme for calibration of EPCs and a procedure for field installation is presented.
Abstract: An earth pressure cell (EPC) is a device designed to provide an estimate of normal stress in soil. The practice of designing and manufacturing stress-measurement devices revolves around the study of the interaction between the measuring device and the host material. However, distribution of normal stress is not necessarily uniform across a given surface. Consequently, output from an EPC may be different under soil-loading conditions than under fluid pressure. In addition, depending on the design, as the cell deflects, an arching-type phenomenon may develop. A study was conducted to devise a scheme for calibration of EPCs and to recommend a procedure for field installation. A new testing device was designed to permit the application of uniaxial soil pressure to the EPC by using various types of soil and load configurations. Sensitivities computed from soil calibrations varied from those determined from fluid calibrations by as much as 30 percent. A field installation procedure was developed from model test...
TL;DR: In this paper, the deformation and pore-water pressure responses of clay-ey soils are studied for loading and unloading of a clay subjected to the loading of a load.
Abstract: The deformation and pore-water pressure responses of clayey soils are of great interest to civil engineers. In this paper, displacements and pore-water pressures of a clay subjected to the loading ...
TL;DR: In this paper, the pullout resistance of locally available nonwoven geotextiles taking into account different test parameters has been evaluated and the results indicated the existence of three stages of deformation in the geotexxtile under pull-out testing, which ultimately lead to the slippage of the entire geotetex strip.
Abstract: Sabkha soil is abundant along the Arabian Gulf and Red Sea coasts and is a problematic soil due to its acute water sensitivity and chemical aggressiveness. In many situations, it is required to improve the load carrying capacity of sabkha, and the use of geotextiles was found appropriate. The objectives of this research were to study frictional characteristics of sand-geotextile-sand and sabkha-geotextile-sand interfaces and to compare the pull-out resistance of locally available nonwoven geotextiles taking into account different test parameters. An experimental setup was developed to conduct the pull-out tests. These test results have indicated the existence of three stages of deformation in the geotextile under pull-out testing, which ultimately lead to the slippage of the entire geotextile strip. The use of the pull-out plate reduces the effects of the lateral earth pressure developed on the front wall of the pull-out box and ensures that the free geotextile is kept within the box and, thus, under the ...
Patent•
25 Dec 2001
TL;DR: In this article, a vertical filling method was proposed to provide a vertical retaining wall capable of having high durability against initial earth pressure despite a thin material obtaining critical stability and eliminating a soldier beam in the case of positioning of pile.
Abstract: PROBLEM TO BE SOLVED: To provide a vertical filling method retaining wall capable of having high durability against initial earth pressure despite a thin material obtaining critical stability and eliminating a soldier beam in the case of positioning of pile. SOLUTION: A process for constructing a vertical retaining wall 1, a process performing a cement stably treated fill 14 on the back of the retaining wall 1 at a predetermined interval to horizontally bury a first anchor bar 10 in the filling toward the retaining wall 1, a process for jointing the projected end from a filling layer of the anchor bar 10 and a second anchor bar 8 connected to the back of the retaining wall 1 and projected toward the filling side and a process for backfilling a gap formed between the filling and the back of the retaining wall with the filling of the cement stably treated earth after the filling has been cured are used for a repeated method, the retaining wall 1 comprises an earth retaining board 2 having the center curved and swelled in the shape of an arch toward the filling side and a holding steel material 3 placed to the ends of the earth retaining boards 2 adjacent to each other in the horizontal direction and holding the earth retaining boards 2, and the retaining wall connecting end of the second anchor bar 8 is fastened to the holding steel material 3 to connect between the earth retaining boards 2 adjacent to each other through the holding steel material 3 and, at the same time, the earth retaining board 2 is held in an independent state. COPYRIGHT: (C)2003,JPO
Journal Article•
TL;DR: Based on the thought of deformation control design and the characteristics of earth pressure changing with the displacement of retaining wall, the earth pressure computational method considering deformation is presented in this paper, where the agreement of resuts of calculation and centrifugal model test shows the reasonableness of the model.
Abstract: Based on the thought of deformation control design and the characteristics of earth pressure changing with the displacement of retaining wall the earth pressure computational method considering deformation is presented． The agreement of resuts of calculation and centrifugal model test shows the reasonableness of the model． At the end Rankine earth pressure model considering deformation is also derived．
TL;DR: In this paper, the effects of a tracked vehicle of total weight 9.8 kN mounted with a centrifugal or vertical oscillator on a high lifted decomposed weathered granite sandy soil were compared for a frequency of about 54 Hz.
Journal Article•
TL;DR: In this paper, three joint interaction models corresponding to different forms of joint between primary and secondary linings are suggested to calculate the stress of the linings, and the calculation results show that the assumption of secondary lining solely bearing the total water and soil pressure is not correct and may induce unsafe errors in lining design.
Abstract: Two kinds of load combination model are proposed for different situations of external water and soil pressure In the mean time three joint interaction models corresponding to different forms of joint between primary and secondary linings are suggested Programs for FEM to calculate the stress of the linings are coded The calculation results show that the assumption of secondary lining solely bearing the total water and soil pressure is not correct and may induce unsafe errors in lining design It is recommended that the commended that the coupling bwtween primary and secondary linings must be reinforced forming an integrated structure to bear the external pressure
01 Sep 2001
TL;DR: In this article, the effect of wall friction on bending moments computed using classical design procedures and one-dimensional soil-structure interaction is examined, and comparisons are made between different methods of computing soil pressures which incorporate the effects of surcharge loads.
Abstract: : This report presents the results of three separate investigations pertaining to anchored sheet-pile walls. The effect of wall friction on bending moments computed using classical design procedures and one-dimensional soil-structure interaction is examined. Also comparisons are made between different methods of computing soil pressures which incorporate the effects of surcharge loads. Finally, moment reduction curves from several different sources are compared.
Patent•
25 Oct 2001
TL;DR: In this article, an electric static cone penetration test is carried out at a representative point in an execution area; after the obtainment of cone end resistance before the driving of the pile or the sand compaction pile, a test for obtaining the cone end resistances after the driving was carried out by driving a plurality of test piles or test sand compaction piles; and the coefficient of the earth pressure at rest of sandy ground is calculated for evaluation from test results.
Abstract: PROBLEM TO BE SOLVED: To provide a method for evaluating a coefficient of earth pressure at rest of ground into which a pile or a sand compaction pile is driven, which allows the proper evaluation of an increase in the coefficient of the earth pressure at rest of the ground due to the driving of the pile or the sand compaction pile, and enables the coefficient of the earth pressure at rest to be properly and simply applied to a design. SOLUTION: In this method, an electric static cone penetration test is carried out at a representative point in an execution area; after the obtainment of cone end resistance before the driving of the pile or the sand compaction pile, a test for obtaining the cone end resistance after the driving is carried out by driving a plurality of test piles or test sand compaction piles; and the coefficient of the earth pressure at rest of sandy ground is calculated for evaluation from test results.