Showing papers on "Lateral earth pressure published in 1969"
TL;DR: For relatively shallow anchors in undisturbed dense and stiff soils, general shear along a convex, torical slip surface is observed as mentioned in this paper, which degenerates into a cylindrical surface for remolded, compressible and semiliquid soils.
Abstract: Soil resistance to withdrawal is found to be greatly affected by failure patterns. For relatively shallow anchors in undisturbed dense and stiff soils general shear along a convex, torical slip surface is observed. For remolded, compressible and semiliquid soils this pattern degenerates into a cylindrical surface. For deeply embedded objects punching shear failure is observed. In semiliquid soils this is accompanied by flow of soil into the vacuum created by withdrawal of the object. Theoretical analysis considering soil to be rigid-plastic near the surface and elastic-plastic at greater depth appears to give reasonable estimates in soft and loose soils; it underestimates the breakout resistance in stiff and dense soils. The least understood components of breakout force are those attributed to soil suction and adhesion between the object and surrounding soil. It appears that the problem of soil suction can be handled as a problem of pore-pressure difference on two sides of the pulled object.
246 citations
TL;DR: In this article, the authors presented a study of a model with glass sides to determine the RUPTURE SURFACES and the DISTRIBUTION of PRESSURES on a RIGID RETAINING WALL.
Abstract: RESULTS ARE PRESENTED OF A STUDY PRESSURE MODEL WITH GLASS SIDES TO DETERMINE THE RUPTURE SURFACES AND THE DISTRIBUTION OF PRESSURES ON A RIGID RETAINING WALL. EMPHASIS IS LAID ON THE EFFECT OF ROTATION OF THE WALL ON THE MAGNITUDE AND DISTRIBUTION OF PRESSURE AND SHAPE AND SIZE OF THE RUPTURE WEDGE. IT IS CONCLUDED THAT THE TYPE OF WALL DISPLACEMENT IS ONE OF THE IMPORTANT FACTORS AFFECTING THE PRESSURES AND THE RUPTURE WEDGE. FURTHER, IT IS POINTED OUT THAT THE COMMON EARTH PRESSURE THEORIES ARE INADEQUATE TO ASSESS PASSIVE PRESSURES CORRECTLY. /ASCE/
50 citations
TL;DR: In this article, Larkin investigated the reason for the discrepancy in the BEARING CAPACITY results reported by the author and in other studies and found that the root strength of the SOIL ABOVE the base of the FOOTING in the SLIP LINE FIELD can be attributed to the presence of very shallow footprints.
Abstract: THE REASON WAS INVESTIGATED FOR THE DISCREPANCY IN THE BEARING CAPACITY RESULTS OBTAINED BY THE AUTHOR AND IN OTHER STUDIES THE AUTHOR TAKES THE SHEAR STRENGTH OF THE SOIL ABOVE FOUNDATION LEVEL INTO ACCOUNT, BUT ACCORDING TO A PRESENTED FIGURE, THE RANKINE ZONE IS SIMPLY EXTENDED ABOVE THIS LEVEL, AND IT IS ALSO IMPLIED THAT A PASSIVE EARTH PRESSURE CORRESPONDING TO A PERFECTLY SMOOTH WALL IS ACTING ON EACH OF THE TWO VERTICAL FACES AB OF THE FOOTING THIS PROBLEM IS UNDER STUDY AT THE DANISH GEOTECHNICAL INSTITUTE THE THEORETICAL CALCULATION OF BEARING CAPACITIES FOR CIRCULAR FOOTINGS ARE OPEN TO DOUBT ON TWO POINTS WHICH ARE DISCUSSED THE HAAR AND VON KARMAN HYPOTHESIS IS INCOMPATIBLE WITH THE PROPORTIONALITY BETWEEN THE PLASTIC STRAIN AND THE DEVIATOR STRESS TENSORS POSTULATED BY REUSS, AND THE USE OF THE HAAR AND VON KARMAN HYPOTHESIS IMPLIES THAT THE FRICTION ANGLES FOR WHICH THE AVERAGE BEARING PRESSURES ARE CALCULATED ARE THOSE CORRESPONDING TO A TRIAXIAL STATE OF STRAIN MR KARAFIATH COMMENDS THE NUMERICAL METHOD USED BY THE AUTHOR TO INVESTIGATE THE THEORETICAL BEARING CAPACITY OF SHALLOW FOOTINGS IT IS RECOMMENDED THAT THE COMPUTER PROGRAM BE ADAPTED TO VARIOUS BOUNDARY CONDITIONS, AS THE AUTHOR ADAPTED THE METHOD TO INCLUDE THE SOIL ABOVE THE BASE OF THE FOOTING IN THE SLIP LINE FIELD RATHER THAN CONSIDERING IT AS A SURCHARGE THE WRITER AGREES WITH THE AUTHOR THAT OTHER FACTORS, SUCH AS ROUGHNESS OF THE FOOTING, ALSO HAVE SIGNIFICANT INFLUENCES ON BEARING CAPACITY THIS EFFECT MAY BE EASILY INVESTIGATED BY THE NUMERICAL METHOD REFERENCES: THEORETICAL BEARING CAPACITY OF VERY SHALLOW FOOTINGS, LAWRENCE A LARKIN, ASCE PROCEEDINGS PAPER 6258, NOVEMBER, 1968
36 citations
TL;DR: In this paper, the authors described the stress-strain characteristics of dry sands under cyclic loading and showed that the soil deformation state primarily of shear deformation, and that the magnitude of the principal stress ratio above which large strains may develop under vibration, is dependent on the confining pressure.
Abstract: The stress-strain characteristics of dry sands under cyclic loading is described. Within the range of stress and acceleration studied, the soil deformation state primarily of shear deformation. While the volumetric compression of the soil always increases under cyclic loading, its contribution to the total strain remains small. The magnitude of the principal stress ratio, above which large strains may develop under vibration, is dependent on the confining pressure. At a low confining pressure (7 psi) this ratio is about 1/2 of the principal stress ratio for failure in static tests. At a higher confining pressure (20 psi), it is about 3/4 of the static ratio for foundation vibration problems, the strong influence of the confining pressure implies that a rather important size effect may arise. For two foundations of unequal size, loaded to equal unit pressure, the zone of stressed soil beneath the larger foundation would extend to a larger depth. The average confining pressure on the soil in this zone would also be greater.
21 citations
01 Mar 1969
Abstract: LARGE DIAMETER DRILLED SHAFTS ARE USED EXTENSIVELY IN MANY AREAS OF THE WORLD TO SUPPORT AXIAL LOADS; HOWEVER, THE BEHAVIOR OF THESE SHAFTS IS NOT WELL UNDERSTOOD. FREQUENTLY THEY ARE DESIGNED AS POINT-BEARING SHAFTS ONLY, WITH NO ACCOUNT BEING TAKEN OF LOAD DISTRIBUTED ALONG THE SIDES OF THE SHAFT. QUESTIONS ARISING WITH REGARD TO THE DESIGN OF SUCH SHAFTS CONCERN THE INTERACTION OF WET CONCRETE WITH SOIL, THE POSSIBLE SHRINKAGE OF CONCRETE ON DRYING, THE EVENTUAL EARTH PRESSURE AT THE INTERFACE OF THE SHAFT AND THE SUPPORTING SOIL, AND THE MECHANICS OF THE INTERACTION OF THE SHAFT WITH THE FOUNDATION. THIS REPORT DESCRIBES A COMPREHENSIVE INVESTIGATION AIMED AT GAINING MORE INFORMATION RELATED TO THE ABOVE QUESTIONS. A 30-INCH BY 28.5-FOOT DRILLED SHAFT WAS INSTRUMENTED WITH ELECTRICAL RESISTANCE STRAIN GAGES, MECHANICAL STRAIN GAGES, EARTH PRESSURE CELLS, AND THERMOCOUPLES AND WAS SUBSEQUENTLY TESTED UNDER AXIAL LOAD. THE INSTRUMENTS WERE READ FOR A SERIES OF LOAD INCREMENTS. THE SHAFT WAS TESTED FIVE TIMES WITH LOADS RANGING UP TO ALMOST 1,000 TONS. THE TEST DATE WERE ANALYZED TO OBTAIN CURVES GIVING DISTRIBUTION OF AXIAL LOAD ALONG THE SHAFT AS A FUNCTION OF DEPTH AND CURVES SHOWING LOAD TRANSFER AT VARIOUS DEPTHS AS A FUNCTION OF DOWNWARD MOVEMENT OF THE SHAFT AT THAT DEPTH. RESULTS OF THESE ANALYSES WERE CORRELATED WITH SOIL PROPERTIES OBTAINED FROM TEXAS HIGHWAY DEPARTMENT CONE PENETROMETER TESTS. A TENTATIVE DESIGN PROCEDURE IS PROPOSED AND THE LOAD-SETTLEMENT CURVES COMPUTED BY THIS DESIGN PROCEDURE ARE COMPARED WITH THE OBSERVED CURVES. /AUTHOR/
17 citations
TL;DR: In this article, the seismic force is first assumed to act in a certain direction from the vertical, and this direction is optimized so that its effect is maximum on the earth pressures.
10 citations
01 Jan 1969
4 citations
Book•
01 Jun 1969
TL;DR: In this paper, the authors present a method of measuring positive and negative pressure in soil using an end-to-end test. But, the authors do not consider the effect of changing soil conditions.
Abstract: AN ACCURATE METHOD OF MEASURING PORE PRESSURE IN SOILS IS NECESSARY FOR DETERMINING STRESS WHEN DESIGNING SOIL STRUCTURES. THE BUREAU OF RECLAMATION HAS MADE THE FOLLOWING ADVANCES IN MEASURING NEGATIVE PORE PRESSURES. IN THE EXPOSED END PLATE METHOD OF MEASURING THE INITIAL NEGATIVE PORE PRESSURE OF SOILS, THE NEGATIVE PORE PRESSURE CAN BE DETERMINED ON A ROUTINE LABORATORY TESTING BASIS ON SPECIMENS WITHOUT DAMAGING THEM FOR FURTHER TESTING. CAPILLARY PRESSURE IS MEASURED THROUGHOUT THE VOLUME CHANGE RANGE AS THE UNDRAINED (SEALED) SPECIMENS ARE COMPRESSED FROM INITIAL NEGATIVE PORE PRESSURE TO THE POINT WHERE THE CAPILLARY PRESSURE BECOMES ZERO AT SATURATION. RESULTS OF THIS TEST CONDUCTED ON ONE OF A SERIES OF SPECIMENS, TOGHETHER WITH RESULTS OF THE EXPOSED END PLATE TEST ON EACH SPECIMEN OF THE SERIES ARE APPLIED IN THE ANALYSIS OF SOIL STRENGTH FROM SHEAR TEST RESULTS. IMPROVED ACCURACY IS ACHIEVED IN MEASURING PORE AIR PRESSURE BY SEPARATING THE WATER FILM IN THE SOIL FROM THE END PLATE MEASURING DEVICE AND CONTROLLING THE END PLATE SO THAT WATER IS NOT DRAWN INTO OR FROM THE SOIL. VARIABLE SOIL STRESS CONCITIONS THAT WOULD BE INTRODUCED BY CHANGING SOIL MOISTURE CONDITIONS ARE ELIMINATED. /AUTHOR/
3 citations
TL;DR: In this article, a solution is presented for finding the result of Earth's pressure against BRACING using the LOGARITHMIC SPIRAL METHOD, which is based on the MOHR-COUlomb FAILURE CRITERION.
Abstract: A SOLUTION IS PRESENTED FOR FINDING THE RESULTANT EARTH PRESSURE AGAINST BRACING USING THE LOGARITHMIC SPIRAL METHOD. THE SOLUTION CONSIDERS BOTH ADHESION AND FRICTION BETWEEN THE BRACING AND THE SOIL. THE ANALYSIS IS ON A TOTAL STRESS BASIS ONLY. THE SHEARING RESISTANCE OF THE SOIL IS BASED ON THE MOHR-COULOMB FAILURE CRITERION. THE SOLUTION IS OBTAINED BY TRIAL AND ERROR, USING A DIGITAL COMPUTER AND VARYING THE POSITION OF THE FAILURE SURFACE UNTIL MAXIMUM PRESSURE AGAINST THE BRACING IS OBTAINED. THE VARIABLES USED FOR THE SOLUTION ARE: THE ANGLE OF INTERNAL FRICTION OF THE SOIL, THE ANGLE OF WALL-FRICTION, THE RATIO OF THE DISTANCE FROM THE BOTTOM OF THE EXCAVATION TO THE POINT OF APPLICATION OF THE RESULTANT EARTH PRESSURE TO THE TOTAL HEIGHT OF THE VERTICAL FACE, AND THE PRODUCT OF THE UNIT WEIGHT OF THE SOIL AND THE TOTAL HEIGHT OF THE VERTICAL FACE. VALUES FOR THE MAGNITUDE OF THE RESULTANT EARTH THRUST ARE PRESENTED IN A TABLE.
3 citations
Journal Article•
TL;DR: In this paper, the authors investigate the effect of different levels of stress on the performance of loading and reloading of a bicycle in four different states of the United States, and conclude that the effect increases with higher stress levels.
Abstract: THE OBJECTIVE WAS TO DETERMINE THE INFLUENCE OF DENSITY, GRADATION, CONSOLIDATION STRESS LEVEL, AND LOAD HISTORY ON THE COEFFICIENT OF EARTH PRESSURE AT REST. A CONSOLIDATION APPARATUS IS DESCRIBED THAT PERMITS GRADUAL LOAD APPLICATION AT A DESIRED RATE OF LOADING, WHILE VERTICAL AND LATERAL STRESSES ARE SIMULTANEOUSLY OBSERVED UNDER THE CONDITION OF NO LATERAL YIELDING. THE FRICTION LOADS INHERENT IN THE NORMAL CONSOLIDATION TESTING WERE ALSO OBSERVED AND THEIR MAGNITUDE IS REPORTED TO BE HIGHER FOR LOOSE AND FINER GRAIN SOILS THAN FOR THE DENSE AND COARSER GRAIN SOILS. FOUR GRANULAR SOIL SPECIMENS WERE TESTED IN LOOSE, MEDIUM COMPACT AND COMPACT STATES. THE RESULTS CLEARLY DEMONSTRATE THAT THE COEFFICIENT OF EARTH PRESSURE AT REST IS LESS FOR THE DENSE STATE THAN FOR THE LOOSE STATE AND THAT IT DECREASES WITH HIGHER CONSOLIDATION STRESS LEVELS. THE INFLUENCE OF GRADATION IS ALSO APPARENT FROM THE RESULTS, BUT IT IS LESS PRONOUNCED. APPROXIMATE VALUES OF POISSON'S RATIO WERE COMPUTED ON THE BASES OF THE ZERO LATERAL STRAIN CONDITION WHICH EXISTS IN CONSOLIDATION AND THE ASSOCIATED RATIO OF THE VERTICAL AND LATERAL STRESS. THE STRESS HISTORY STUDIES, SIMULATED BY PERFORMING A NUMBER OF UNLOAD ANDD RELOAD CYCLES DEMONSTRATED THE 'LOCKED-IN' OR RESIDUAL STRESS PHENOMENON WHICH IS ASSOCIATED WITH CONSOLIDATION OF SOILS SUBJECTED IN THEIR LOAD HISTORY TO UNLOADING AND RELOADING CYCLES. THESE STUDIES POINT OUT THE IMPORTANCE OF CONSIDERING THE STRESS CONDITIONING OF SOILS THAT MAY BE CAUSED BY ROLLING OF EMBANKMENTS OR PAVEMENT LAYERS. REPRODUCING THIS STATE OF STRESS AS AN INITIAL TEST CONDITION IS CONSIDERED ESSENTIAL IN ANY SIGNIFICANT TESTING OF PAVEMENT OR EMBANKMENT MATERIALS. /AUTHOR/
Book•
01 Jan 1969
TL;DR: In this article, the authors investigated the bearing capacity of a soft clay soil and the analysis of the failure of an earth dam during construction, and showed that the failure was caused by the underdrainage of London clay.
Abstract: Contents:On railway cuttings and embankments with an account of some slips in London Clay .../CH Gregory; The actual lateral pressure of earthwork/B Baker; On the horizontal thrust of a mass of sand/GH Darwin; The lateral pressure and resistance of clay, and the supporting power of clay foundations/AL Bell; The shearing resistance of soils/LF Cooling & DB Smith/ Soil mechanics-a new chapter in engineering science/K von Terzaghi; The ultimate bearing pressure of rectangular footings/HQ Golder; A laboratory study of London clay/LF Cooling and AW Skempton; Soil mechanics and site exploration/LF Cooling; An investigation of the bearing capacity of a soft clay soil/AW Skempton; The analysis of the failure of an earth dam during construction/LF Cooling & HQ Golder; The settlement of London due the underdrainage of the London clay/G Wilson & H Grace; The basic principles of soil compaction and their application/AHD Markwick; Particle-size in silts and sands/R Glossop & AW Skempton; Earth pressure and earth resistance/S Packshaw; The choice of expedients in civil engineering construction/HJB Harding
TL;DR: In this paper, field studies were made of an ARCH CULVERT EMBEDDED in a DEEP EMBANKMENT and SURMOUNTED by LAYERS OF STRAW.
Abstract: FIELD STUDIES WERE MADE OF AN ARCH CULVERT EMBEDDED IN A DEEP EMBANKMENT AND SURMOUNTED BY LAYERS OF STRAW. QUASITHEORETICAL INTERNAL STRESSES RESULTING FROM MEASURED SOIL PRESSURES ACTING AT THE EXTRADOS WERE CORRELATED WITH MEASURED STRAINS. INTERNAL STRESSES WHICH MIGHT RESULT FROM VARIOUS HYPOTHETICAL HYDROSTATIC LOADINGS WERE COMPUTED AND COMPARED WITH THOSE DUE TO ACTUAL LOADINGS, AND THE INDIVIDUAL INFLUENCES OF MEASURED SOIL PRESSURES AND OBSERVED DIFFERENTIAL FOOTING MOVEMENTS WERE EVALUATED. BEHAVIOR OF THE SOIL MASS WITH RESPECT TO THE RIGID ARCH CULVERT IS SHOWN TO BE HYDROSTATIC IN NATURE TO THE EXTENT THAT SOIL PRESSURES ACTING ON THE BARREL WERE LINEAR FUNCTIONS OF EMBANKMENT HEIGHT. NEGLIGIBLE CHANGES IN SOIL PRESSURES WERE OBSERVED FOLLOWING COMPLETION OF EMBANKMENT CONSTRUCTION. THREE CAUSES OF OBSERVED DISTRESS IN THE PROTOTYPE ARE INDICATED. /AUTHOR/
TL;DR: Soil has its origin in physical processes of comminution and abrasion of rock masses and in chemical processes of solution and recrystallization of rock minerals as mentioned in this paper, and it is transported and distributed by a variety of agencies before subaerial or subaqueous deposition.
Abstract: Soil has its origin in physical processes of comminution and abrasion of rock masses and in chemical processes of solution and recrystallization of rock minerals. After formation it is transported and distributed by a variety of agencies before subaerial or subaqueous deposition. Generally, soils experience a number of cycles of sedimentation, uplift, erosion and redeposition. Their mechanical behaviour under the stresses imposed by engineering structures varies with the type of soil. Both the deformation and failure of soils are of interest in the design of structures and these properties must be studied by special laboratory tests. The solution of a soil engineering problem therefore involves a field investigation and sampling programme to define the boundaries of the soil involved, laboratory testing of the soil, and analytical or computer calculations to determine the displacements and stresses which will occur in the soil and structure. Problems of particular interest include slope failures, the design of earth dams, retaining walls and piled structures, the displacement and failure of soil under buildings and the determination of soil properties on the surface of the moon and other planets.