scholarly journals Ultimate Lateral Resistance of Anchor Plates in Cohesionless Soils

1966 ◽  
Vol 6 (04) ◽  
pp. 299-307
Author(s):  
A.O.P. Casbarian
Keyword(s):  
Ground Surface ◽  
Earth Pressure ◽  
Resistance Factor ◽  
Cohesionless Soil ◽  
Cohesionless Soils ◽  
Dimensionless Variable ◽  
The Earth ◽  
Theory Of Plasticity ◽  
Lateral Resistance ◽  
Ultimate Resistance

Abstract An analytical method is developed to determine the variation of the ultimate lateral resistance of a plate in a cohesionless soil with depth. This analysis is based on a modification of Rankine's classical earth pressure theory and the theory of plasticity as applied to soils. The ultimate resistance is defined as the product of the effective stress at the midpoint of the plate, the area of the plate and a dimensionless variable termed the ultimate resistance factor. This variable has been plotted vs the depth ratio; i.e., the ratio of the depth of embedment vs the height of the plate. The resistance of a plate may then be calculated using the values of the ultimate resistance factor from the chart provided or the equation may be programmed for use in an analysis of anchor systems in cohesionless soils. It is emphasized that the analysis is semitheoretical. The theory has been compared with experimental results reported in the literature and results indicate general agreement. Actual field tests are necessary to further verify this theory. INTRODUCTION With the exploration for oil offshore in waters all over the world, it is of importance to determine the behavior of the various soils in relation to their ultimate resistance to deformation. Examples of such problems are the holding capacity of anchors and the lateral resistance of piles. Very little information is available in the published literature on the design and performance of anchors, in either cohesive or cohesionless soils. The analysis developed in this report is the first step in obtaining a solution for the determination of anchor holding capacity in a cohesionless material. DISCUSSION The theory used in the analysis is based on the ultimate strength of the soil and is the maximum resistance developed by the plate against further movement. In such a state the elastic deformations are disregarded in comparison with the plastic deformations. Hence, the plate can be considered as completely rigid. The theory of plasticity determines the three unknown stresses at any point by means of two equilibrium conditions for a small earth element in combination with the failure condition. However, the exact solutions can only be carried out in a few simple cases such as, for example, when the rupture or failure lines are straight (Rankine theory) or with spiral and straight rupture lines (Prandtl theory ).1 Kötter2 derived a single equation expressing the variation of the stress in any given rupture line. To utilize this equation, it is necessary to know the stress in the rupture line at a certain point. Unfortunately, this is difficult to obtain unless the rupture line intersects the free surface at a certain angle or when the earth is cohesionless and unloaded. A method to overcome this is to consider only the boundary conditions at both ends of a rupture line without investigating the equilibrium of the earth above the rupture line. This assumes that the rupture lines meet the surface at statically correct angles, so that boundary stresses may be determined. As Kötter's equation furnished a relation between these stresses, the unit earth pressure may be calculated at the point where the rupture line meets the wall. Another way in which Kötter's equation may be applied is in investigating the equilibrium of a soil mass above a rupture line. This method assumes that the failure or rupture line is known and that the boundary stresses in the rupture line at the ground surface can be determined. In this case it is possible to determine the earth pressure from the equations of equilibrium.

Ultimate Resistance Against a Rigid Cylinder Moving Laterally in a Cohesionless Soil

1962 ◽  
Vol 2 (04) ◽  
pp. 355-359 ◽  
Author(s):  
Lymon C. Reese
Keyword(s):  
Complete Solution ◽  
Earth Pressure ◽  
Additional Research ◽  
Cohesionless Soil ◽  
Soil Resistance ◽  
Offshore Structure ◽  
Rigid Cylinder ◽  
Laterally Loaded Pile ◽  
Laterally Loaded ◽  
Ultimate Resistance

Abstract The ultimate resistance against a rigid cylinder which is moved laterally in a cohesionless soil is a function of the geometry of the cylinder and the properties of the soil. An approximate method is developed for computing this resistance and is tested against results of laboratory experiments. Satisfactory agreement between the method and experiment was obtained. Not only was the ultimate resistance against the cylinder measured, but careful measurements were made of the shape of the rupture surfaces. These measurements should allow the development of a more rigorous computation procedure. Introduction A critical aspect in the design of offshore drilling platforms is assuring the stability of the platform during a hurricane. The large horizontal loads from waves and wind make a severe loading condition. Piles are generally employed as the foundation since they can be effective in resisting both horizontal and vertical loads. Spuds are sometimes used with a mat foundation, where the spuds are designed principally to resist horizontal loads and the mat designed principally to resist vertical loads. The research reported in this paper is related to one aspect of the problem of laterally loaded piles or spuds in sand. The complete solution to the problem of the laterally loaded pile in sand would require the prediction of soil resistance against the pile as a function of pile deflection; only the ultimate resistance against short piles is considered in this paper. A considerable amount of additional research will be necessary to obtain a complete solution to the problem of the laterally loaded pile in sand; however, the work reported here should be useful as a guide in the performance of some of the additional research. ULTIMATE LATERAL RESISTANCE AGAINST A LONG WALL IN SAND To aid in the understanding of the theory which is developed for a cylinder, the theory for earth pressure against a wall is reviewed. In Fig. 1(a), a long wall of height H is shown embedded in soil. Soil resistance will develop as the wall is deflected, and the soil resistance will increase with deflection until some limiting value is reached. In this discussion, and those following, it is assumed that all points on the wall deflect equal amounts. A possible shape of the real curve which relates soil resistance to deflection is shown by the dashed line in Fig. 1(b); however, as a means of simplifying the discussion, an idealized curve (shown by the unbroken lines) is drawn. If such a wall as this were furnishing the horizontal support for an offshore structure, the dashed curve in Fig. 1 would be the information needed in performing a foundation analysis, with the idealized curve possibly being an acceptable substitute. SPEJ P. 355^

An examination of some theories of earth pressure on shaft linings

1977 ◽  
Vol 14 (1) ◽  
pp. 91-106 ◽  
Author(s):  
E. G. Prater
Keyword(s):  
Pressure Coefficient ◽  
Earth Pressure ◽  
Failure Surface ◽  
Cohesionless Soils ◽  
The Earth ◽  
Earth Pressures ◽  
Coulomb Type ◽  
Earth Pressure Coefficient ◽  
The One ◽  
Similar Theory

Various theories for determining the earth pressure on shaft linings in cohesionless soils are discussed, and results are presented for a Coulomb-type analysis with a conical sliding surface. The assumed shape of the failure surface approximates closely the one given in published results obtained by the method of characteristics. The simplicity of the cone permits an investigation of a number of parameters, e.g. the earth pressure coefficient on radial planes, which turns out to be a decisive parameter in the analysis, and accounts for the widely differing published values for earth pressures on shaft linings. Certain theories could lead, especially at greater depths, to rather conservative designs.A similar theory is also presented for earth pressures on shafts in cohesive soils. In this case the possibility of base failure must be considered as well, and it is shown that this might be the deciding failure mechanism.

Determination of apparent earth pressure diagram for anchored walls in c–φ soil with surcharge

2020 ◽  
Vol 17 (4) ◽  
pp. 481-489
Author(s):  
Seyyed Pouya Alavinezhad ◽  
Hadi Shahir
Keyword(s):  
Retaining Wall ◽  
Ground Surface ◽  
Earth Pressure ◽  
Ground Level ◽  
Content Type ◽  
Lateral Earth Pressure ◽  
The Earth ◽  
Real Distribution ◽  
Strain Modeling

Purpose The purpose of this study is to present a diagram for the lateral earth pressure of c–φ soils exerted on anchored walls in presence of surcharge. Design/methodology/approach To this end, two-dimensional plane strain modeling of anchored wall was carried out in Plaxis software. To validate the numerical model, two excavations with different specifications were simulated and the model results were compared with the available results. Subsequently, a parametric analysis was done and based on its results, a diagram was proposed for the lateral earth pressure of c–φ soils including the surcharge effects. Findings The proposed diagram without the surcharge and cohesion effects is a trapezoidal with zero value at the ground surface that is linearly approaching the apparent earth pressure of sand according to Terzaghi and Peck (1967) at 0.1H (H: wall height). The surcharge and cohesion effects at the ground level is 4 Ka*q and 0, respectively, and below 0.1H, they are treated as the same way for lateral earth pressure of a retaining wall. It should be emphasized that the apparent pressure diagram for design does not resemble the real distribution of earth pressure against the wall and it is for calculating the values of the anchors loads. Originality/value The available diagrams to determine the earth pressure exerted on the anchored walls are related to sandy or clayey soils and do not take the presence of surcharge into account. Thus, the proposed diagram is quite original and different from the previous ones.

Control of Water and Sand Gush in Tunnelling with Earth Pressure Balanced Compound Type Shield

2011 ◽  
Vol 243-249 ◽  
pp. 3349-3354
Author(s):  
Jin Shan Lei ◽  
Li Ping Yan ◽  
Xiu Zhu Yang ◽  
De Zhi Liu
Keyword(s):  
Ground Surface ◽  
Earth Pressure ◽  
Fine Sand ◽  
Sand Layer ◽  
High Permeability ◽  
Foam Material ◽  
Front End ◽  
The Earth ◽  
Compound Type ◽  
Tunnel Shield

The sixth line of Guangzhou Metro Subway is partially located in silty fine sand layer, which is incompact, rich in water, and has high permeability and low bearing capability. When tunnelling in this section, it is easy to bring about gush of water and sand, which will cause the ground surface to settle. Therefore, a two-staged helical conveyer was used to control this phenomenon during tunnelling. First, both the dregs outlets of helical conveyer are turned off to prevent water and sand from rushing forth, then foam material is injected into the earth cabin and the front-end of helical conveyer to keep the cabin pressure from decreasing. Secondly, drain outlet of the second helical conveyer is turned on and the water is drained, then dregs outlet of the second helical conveyer is turned on to discharge the dregs. Finally, dregs outlet of the first helical conveyer is turned on to discharge the dregs in the earth cabin. Such technique was used successfully in tunnelling the section from Datansha to Ruyifang of the sixth line of Guangzhou Metro Subway. It ensured that sinking of the ground surface was avoided while the tunnel shield went through the silty fine sand layer that is rich in water.

Coordinated optimization control of shield machine based on dynamic fuzzy neural network direct inverse control

2020 ◽  
pp. 014233122098027
Author(s):  
Xuanyu Liu ◽  
Wentao Wang ◽  
Yudong Wang ◽  
Cheng Shao ◽  
Qiumei Cong
Keyword(s):  
Fuzzy Neural Network ◽  
Control Method ◽  
Earth Pressure ◽  
Screw Conveyor ◽  
Inverse Control ◽  
The Earth ◽  
Coordinated Optimization ◽  
Optimization Control ◽  
Fuzzy Neural ◽  
Shield Machine

During shield machine tunneling, the earth pressure in the sealed cabin must be kept balanced to ensure construction safety. As there is a strong nonlinear coupling relationship among the tunneling parameters, it is difficult to control the balance between the amount of soil entered and the amount discharged in the sealed cabin. So, the control effect of excavation face stability is poor. For this purpose, a coordinated optimization control method of shield machine based on dynamic fuzzy neural network (D-FNN) direct inverse control is proposed. The cutter head torque, advance speed, thrust, screw conveyor speed and earth pressure difference in the sealed cabin are selected as inputs, and the D-FNN control model of the control parameters is established, whose output are screw conveyor speed and advance speed at the next moment. The error reduction rate method is introduced to trim and identify the network structure to optimize the control model. On this basis, an optimal control system for earth pressure balance (EPB) of shield machine is established based on the direct inverse control method. The simulation results show that the method can optimize the control parameters coordinately according to the changes of the construction environment, effectively reduce the earth pressure fluctuations during shield tunneling, and can better control the stability of the excavation surface.

The earth pressure behind full-height integral abutments

2005 ◽  
Vol 90 (6) ◽  
pp. 55-58 ◽  
Author(s):  
Ming Xu ◽  
Alan G. Bloodworth
Keyword(s):  
Earth Pressure ◽  
The Earth ◽  
Integral Abutments ◽  
Full Height

Comportement de pieux d'essais instrumentés sous charge horizontale

1993 ◽  
Vol 30 (1) ◽  
pp. 1-11
Author(s):  
R. Frank ◽  
H. Zervogiannis ◽  
S. Christoulas ◽  
V. Papadopoulos ◽  
N. Kalteziotis
Keyword(s):  
Pile Foundation ◽  
Bending Moment ◽  
Standard Penetration Test ◽  
American Petroleum Institute ◽  
Full Scale ◽  
Test Method ◽  
Cohesionless Soil ◽  
Penetration Test ◽  
Cohesionless Soils ◽  
Final Design

This paper describes the behaviour of two test piles (one bored and postgrouted and one simply bored, both 31.7 m long and 0.75 m in diameter) subjected to horizontal loads. These full-scale pile tests were carried out for the actual design of the pile foundation of a pier of the Evripos cable-stayed bridge. This bridge will link the Euboea Island to mainland Greece. The two piles have already been subjected to bearing capacity tests under axial loadings. The inclinometer measurements, taken during the present tests, yielded, in particular, the deformed shape of the piles as well as the bending moments. Conclusions could be drawn for the final design of the pile foundation with respect to horizontal loadings. Furthermore, various calculation methods using p–y reaction curves for cohesionless soils have been checked: the Ménard pressuremeter method, the method of the American Petroleum Institute recommendations, and the Standard penetration test method of Christoulas. These pile tests show that simple measurements, taken on construction sites, can yield interesting results on the actual behaviour of horizontally loaded piles. Key words : pile, horizontal loading, full-scale test, horizontal loads, bending moment, subgrade reaction modulus, p–y curve, cohesionless soil, Standard penetration test, pressuremeter test.

Experimental Study on Earth Pressure of Corrugated Steel Culvert under High Fill Embankment

2013 ◽  
Vol 405-408 ◽  
pp. 1815-1819
Author(s):  
Wen Sheng Yu ◽  
Zhu Long Li ◽  
Xiao Ru Xie ◽  
Li Yuan Guo
Keyword(s):  
Mechanical Property ◽  
Experimental Study ◽  
Reinforced Concrete ◽  
Concrete Slab ◽  
Earth Pressure ◽  
Reinforced Concrete Slab ◽  
The Earth ◽  
Filling Height ◽  
Test Points ◽  
Better Than

To analyze the earth pressure of corrugated steel culvert under high fill embankment, a field test was taken and the change law was got with the filling height increasing, the force state when geotechnical grilles were laid on the top of corrugated steel culvert was compared to that of reinforced concrete slab culvert. Results show that the pressure on the top of corrugated steel culvert is smaller than that on the external in same level when test points are near to culvert, the values of test points above and below geotechnical grilles are close, and the pressure of corrugated steel culvert is smaller than that of reinforced concrete slab culvert when filling height is above 7.3 m. So analysis indicates corrugated steel culvert spreads the upper load better, the geotechnical grille can reduce the pressure effectively through earth pressure redistribution, and the mechanical property of corrugated steel culvert is better than reinforced concrete slab culvert under high fill embankment.

Sign in / Sign up

Export Citation Format

Share Document