scholarly journals Numerical Study on Uniaxial Compression Behavior of Geobags

2019 ◽  
Vol 8 (4) ◽  
pp. 137-148
Author(s):  
N. Hataf ◽  
M. Javahery
Keyword(s):  
Bearing Capacity ◽  
Coastal Erosion ◽  
Mechanical Characteristics ◽  
Numerical Study ◽  
Load Capacity ◽  
Computer Software ◽  
Compressive Load ◽  
Friction Angle ◽  
Test Results ◽  
Compression Behavior

Geobags have been used as coastal erosion control and flood preventing measures during the last decades. More recently engineers have used geobags to improve the bearing capacity of soft soils. In this paper, a study was performed to investigate the behavior of geobags under compression loadings utilizing a finite element computer software. The numerical modeling was verified by simulating reported laboratory compression test results. The effects of various parameters such as geobag’s dimensions, mechanical characteristics of filling soil and bag material properties on the ultimate bearing capacity of geobags were investigated. It was shown that increasing the friction angle of filling soil and the tensile strength of textile lead to an increase in the geobag ultimate compressive load capacity. On the other hand, an increase in dilation angle of filling soil, Poisson's ratio and the height of geobag lead to a decrease in the ultimate compressive load capacity of geobags.

scholarly journals ANALYSIS OF THE FIELD TESTS RESULTS OF BORED CONICAL PILES UNDER THE ACTION OF VARIOUS TYPES OF LOADS

2018 ◽  
Vol 3 (3) ◽  
pp. 24-29
Author(s):  
Ирина Рыбникова ◽  
Irina Rybnikova ◽  
Александр Рыбников ◽  
Aleksandr Rybnikov
Keyword(s):  
Bearing Capacity ◽  
Load Capacity ◽  
Normal Component ◽  
Cone Angle ◽  
Field Tests ◽  
Side Surface ◽  
Test Results ◽  
Head Diameter ◽  
Cylindrical Piles ◽  
Bored Piles

One of the methods of improving the bearing capacity of bored piles is giving them a taper. The feature of these (wedge-type) piles is that under load they work "as a thrust" and transfer part of the load due to the normal component to the inclined side surface. Three sizes of tapered bored piles were tested, with the length of 4.5 m, head diameter 0.4; 0.5; 0.6 m and with cone angle 1o and 2,5o. The test results were compared with the test results of cylindrical piles, 4.5 m long, with head diameter 0.4 m and 0.6 m. It has been discovered that with the increasing cone angle, the bearing capacity of piles against the pressing load, especially the specific load capacity for 1 m3 of material, as compared to cylindrical piles, increases significantly. It has been determined that the larger is the diameter of the head of the pile, the higher is the bearing capacity against the horizontal load, and the bearing capacity against the pullout load is equal to the breakout force of a pile from the soil.

scholarly journals Numerical Study of Strip Footings Behavior on Compacted Sand

2019 ◽  
pp. 1-10
Author(s):  
Nasser A. A. Radwan ◽  
Khaled M. M. Bahloul
Keyword(s):  
Finite Element ◽  
Bearing Capacity ◽  
Layer Thickness ◽  
Numerical Study ◽  
Computer Software ◽  
Strip Footing ◽  
Loose Sand ◽  
Strip Footings

The aim of this research is to investigate numerically the effect of using compacted sand as soil replacement layer beneath a strip footing on its bearing capacity. Finite element computer software Plaxis 2D version 8.6 was used to predict the behavior of strip footing resting on loose sand and on compacted sand. Study was conducted for footing widths of 1 up to 2 meters and various depths ranging from 1m up to 2m, also the effect of replacement layer thickness was investigated. It was found that using replacement layer beneath strip footing increases its bearing capacity for different widths and depths of footing. This improvement is observed up to thickness of replacement layer equal to 3 times the footing width (H/B=3), where further increase in replacement layer thickness does not affect significantly bearing capacity of footings.

scholarly journals Pressure Settlement Behaviour and Bearing Capacity of Asymmetric Embedded Plus Shaped Footing on Layered Sand

2021 ◽  
Vol 31 (3) ◽  
pp. 152-176
Author(s):  
Priyanka Rawat ◽  
Rakesh Kumar Dutta
Keyword(s):  
Bearing Capacity ◽  
Numerical Study ◽  
Friction Angle ◽  
Thickness Ratio ◽  
Embedment Depth ◽  
Loose Sand ◽  
Dense Sand ◽  
Comparison Of The Results ◽  
Abaqus Software ◽  
Settlement Behaviour

Abstract The aim of the present numerical study was to analyse the pressure settlement behaviour and bearing capacity of asymmetric plus shaped footing resting on loose sand overlying dense sand at varying embedment depth. The numerical investigation was carried out using ABAQUS software. The effect of depth of embedment, friction angle of upper loose and lower dense sand layer and thickness of upper loose sand on the bearing capacity of the asymmetric plus shaped footing was studied in this investigation. Further, the comparison of the results of the bearing capacity was made between the asymmetric and symmetric plus shaped footing. The results reveal that with increase in depth of embedment, the dimensionless bearing capacity of the footings increased. The highest increase in the dimensionless bearing capacity was observed at embedment ratio of 1.5. The increase in the bearing capacity was 12.62 and 11.40 times with respect to the surface footings F1 and F2 corresponding to a thickness ratio of 1.5. The lowest increase in the dimensionless bearing capacity was observed at embedment ratio of 0.1 and the corresponding increase in the bearing capacity was 1.05 and 1.02 times with respect to the surface footing for footings F1 and F2 at a thickness ratio of 1.5.

Numerical study of ultimate bearing capacity of rectangular footing on layered sand

2020 ◽  
Vol 1 (101) ◽  
pp. 15-26
Author(s):  
V. Panwar ◽  
R.K. Dutta
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Bearing Capacity ◽  
Numerical Study ◽  
Friction Angle ◽  
Ultimate Bearing Capacity ◽  
Loose Sand ◽  
Sand Layer ◽  
Element Analysis ◽  
Dense Sand

Purpose: The purpose of this study is to investigate the ultimate bearing capacity of the rectangular footing resting over layered sand using finite element method. Design/methodology/approach: Finite element analysis was used to investigate the dimensionless ultimate bearing capacity of the rectangular footing resting on a limited thickness of upper dense sand layer overlying limitless thickness of lower loose sand layer. The friction angle of the upper dense sand layer was varied from 41° to 46° whereas for the lower loose sand layer it was varied from 31° to 36°. Findings: The results reveal that the dimensionless ultimate bearing capacity was found to increase up to an H/W ratio of about 1.75 beyond which the increase was marginal. The results further reveal that the dimensionless ultimate bearing capacity was the maximum for the upper dense and lower loose sand friction angles of 46° and 36°, while it was the lowest for the upper dense and lower loose sands corresponding to the friction angle of 41° and 31°. For H/W = 0.5 and 2, the dimensionless bearing capacity decreases with the increase in the L/W ratio from 0.5 to 6 beyond which the dimensionless ultimate bearing capacity remains constant for all combinations of parameters. The results were presented in nondimensional manner and compared with the previous studies available in literature. Research limitations/implications: The analysis is performed using a ABAQUS 2017 software. The limitation of this study is that only finite element analysis is performed without conducting any experiments in the laboratory. Further the study is conducted only for the vertical loading. Practical implications: This proposed numerical study can be used to predict the ultimate bearing capacity of the rectangular footing resting on layered sand. Originality/value: The present study gives idea about the ultimate bearing capacity of rectangular footing when placed on layered sand (dense sand over loose sand) as well as the effect of thickness of top dense sand layer on the ultimate bearing capacity. The findings could be used to calculate the ultimate bearing capacity of the rectangular footing on layered sand.

scholarly journals The Bearing Capacity of Circular Footings in Sand: Comparison between Model Tests and Numerical Simulations Based on a Nonlinear Mohr Failure Envelope

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Sven Krabbenhoft ◽  
Johan Clausen ◽  
Lars Damkilde
Keyword(s):  
Bearing Capacity ◽  
Yield Criterion ◽  
Friction Angle ◽  
Triaxial Tests ◽  
Test Results ◽  
Finite Element Program ◽  
Model Foundation ◽  
Element Program ◽  
Confining Pressures ◽  
Good Agreement

This paper presents the results of a series of triaxial tests with dry sand at confining pressures varying from 1.5 kPa to 100 kPa at relative densities of 0.20, 0.59, and 0.84. The results, which are in reasonable accordance with an equation given by Bolton, show that the friction angle is strongly dependent on the stress level and on the basis of the test results, a nonlinear Mohr failure criterion has been proposed. This yield criterion has been implemented in a finite element program and an analysis of the bearing capacity of a circular shaped model foundation, diameter 100 mm, has been conducted. Comparisons have been made with results from 1g model scale tests with a foundation of similar size and a good agreement between numerical results and test results has been found.

scholarly journals Calculations of compressed rods considering experiments over last 100 years

2021 ◽  
Vol 263 ◽  
pp. 02049
Author(s):  
Denis Konin
Keyword(s):  
Bearing Capacity ◽  
Ultimate Load ◽  
Compressive Load ◽  
Cost Effective ◽  
Test Results ◽  
Fe Modelling ◽  
The Past ◽  
Wide Range ◽  
Line Diagram ◽  
Design Cost

The article presents the results of testing and FE-modelling of rods calculated for the central and eccentric compressive load. More than 600 tests have been analysed over the past 100 years, including made by author, in a wide range of slenderness made of steels with a yield strength of up to 1000 MPa. It is established that the existing Russian calculation methods allow us to accurately determine the bearing capacity of the rod for steel of any strength. Verification of calculation method was carried out not only by stresses and ultimate load-bearing capacity, but also by the deformations of the tested rods. It is established that for H-beams and thin- walled pipes, clarification of the design codes is required to be able to design cost-effective designs, since the code formulas give a margin. This is especially true for elements of low flexibility with small eccentricities. To clarify the codes, a method for modelling a three-line diagram of steel operation, verified with the test results, is proposed.

scholarly journals Behavior of Hollow Thin Welded Tubes Filled with Sand Slag Concrete

2016 ◽  
Vol 2016 ◽  
pp. 1-8
Author(s):  
Noureddine Ferhoune ◽  
Meriem Senani ◽  
Abdelhamid Guettala
Keyword(s):  
Bearing Capacity ◽  
Local Buckling ◽  
Compressive Load ◽  
Considerable Effect ◽  
Test Results ◽  
Eccentric Load ◽  
Natural Sand ◽  
Composite Columns ◽  
Ordinary Concrete ◽  
Steel Section

This paper presents the axial bearing capacity of thin welded rectangular steel stubs filled with concrete sand. A series of tests was conducted to study the behavior of short composite columns under axial compressive load; the cross section dimensions were 100 × 70 × 2 mm. A total of 20 stubs have been tested, as follows: 4 hollow thin welded tubes were tested to axial and eccentric load compression, 4 were filled with ordinary concrete appointed by BO columns, 6 were filled with concrete whose natural sand was completely substituted by a crystallized sand slag designated in this paper by BSI, and 6 were tucked in concrete whose natural sand was partially replaced by a crystallized sand slag called BSII. The main parameters studied are the height of the specimen (300 mm–500 mm), eccentricity of load and type of filling concrete. Based on test results obtained, it is confirmed that the length of the tubes has a considerable effect on the bearing capacity and the failure mode. In all test tubes, fracture occurred by the convex local buckling of steel section due to the outward thrust of the concrete; it was observed that the sand concrete improves the bearing capacity of tubes compounds compared to those filled with ordinary concrete.

Bearing capacity of E-shaped footing on layered sand

2021 ◽  
Vol 2 (105) ◽  
pp. 49-60
Author(s):  
S. Nazeer ◽  
R.K. Dutta
Keyword(s):  
Finite Element ◽  
Bearing Capacity ◽  
Shear Failure ◽  
Numerical Study ◽  
Lower Layer ◽  
Friction Angle ◽  
Ultimate Bearing Capacity ◽  
Loose Sand ◽  
Dense Sand ◽  
Square Footing

Purpose: The purpose of this study is to estimate the ultimate bearing capacity of the E-shaped footing resting on two layered sand using finite element method. The solution was implemented using ABACUS software. Design/methodology/approach: The numerical study of the ultimate bearing capacity of the E-shaped footing resting on layered sand and subjected to vertical load was carried out using finite element analysis. The layered sand was having an upper layer of loose sand of thickness H and lower layer was considered as dense sand of infinite depth. The various parameters varied were the friction angle of the upper (30° to 34°) and lower (42° to 46°) layer of sand as well as the thickness (0.5B, 2B and 4B) of the upper sand layer. Findings: The results reveal that the dimensionless ultimate bearing capacity was found to decrease with the increased in the H/B ratio for all combinations of parameters. The dimensionless ultimate bearing capacity was maximum for the upper loose sand friction angle of 34° and lower dense sand friction angle of 46°. The results further reveal that the dimensionless bearing capacity of the E-shaped footing was higher in comparison to the dimensionless bearing capacity of the square footing on layered sand (loose over dense). The improvement in the ultimate bearing capacity for the E-shaped footing was observed in the range of 109.35% to 152.24%, 0.44% to 7.63% and 0.63% to 18.97% corresponding to H/B ratio of 0.5, 2 and 4 respectively. The lowest percentage improvement in the dimensionless bearing capacity for the E-shaped footing on layered sand was 0.44 % at a H/B = 2 whereas the highest improvement was 152.24 % at a H/B = 0.5. Change of footing shape from square to E-shaped, the failure mechanism changes from general shear to local shear failure. Research limitations/implications: The results presented in this paper were based on the numerical study conducted on E-shaped footing made out of a square footing of size 1.5 m x 1.5 m. However, further validation of the results presented in this paper, is recommended using experimental study conducted on similar size E-shaped footing. Practical implications: The proposed numerical study can be useful for the architects designing similar types of super structures requiring similar shaped footings. Originality/value: No numerical study on E-shaped footing resting on layered sand (loose over dense) were conducted so far. Hence, an attempt was made in this article to estimate the bearing capacity of these footings.

scholarly journals Influence of slenderness ratio and sectional geometry on the axial compression behavior of original bamboo columns

2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Yuhan Nie ◽  
Yang Wei ◽  
Linjie Huang ◽  
Ying Liu ◽  
Fenghui Dong
Keyword(s):  
Bearing Capacity ◽  
Axial Compression ◽  
Slenderness Ratio ◽  
Local Buckling ◽  
Ultimate Bearing Capacity ◽  
Thickness Ratio ◽  
Material Strength ◽  
Test Results ◽  
Compression Behavior ◽  
Load Bearing

AbstractBamboo has been widely used as a load-bearing material in construction; however, there are limited studies on the stability of slender original bamboo columns. Based on the experimental investigation of thirty-nine original bamboo columns, parametric analyses were conducted to investigate the influence of the diameter–thickness ratio, cross-sectional area and slenderness ratio on the axial compression behavior of original bamboo columns. The test results indicate that the failure modes of the columns are substantially affected by the slenderness ratio and diameter–thickness ratio. For columns with the same diameter–thickness ratio, the ultimate bearing capacity was negatively correlated with the slenderness ratio, and the highest reduction rate for the load-bearing capacity caused by the slenderness ratio was 44.39%. Under the same slenderness ratio, when the diameter–thickness ratio increased by 18.75%, the ultimate bearing capacity increased by 82.65%. An excessive slenderness ratio may result in local buckling, leading to underutilization of the material strength when failure occurs and substantially reducing the load capacity of bamboo columns. Local buckling can be mitigated by decreasing the slenderness ratio and increasing the diameter–thickness ratio. According to the test results, the model predicting the compressive bearing capacity of the original bamboo column was proposed considering the slenderness ratio and diameter–thickness ratio, and it was indicated that the proposed model can provide satisfactory predictive results.

Discharge-pulse Geotechnical Electro Discharge Technology of Bases Strengthening

2020 ◽  
Vol 787 (12) ◽  
pp. 63-65
Author(s):  
N.S. Sokolov
Keyword(s):  
Bearing Capacity ◽  
Mechanical Characteristics ◽  
Discharge Pulse ◽  
Zero Values ◽  
Traditional Technologies ◽  
Negative Friction ◽  
Geotechnical Problems ◽  
Physical And Mechanical Characteristics

The problem of increasing the bearing capacity of the base is an relevant problem in modern geotechnical construction. When significant loads are transmitted to the base, the use of traditional technologies is not always justified. Often there is an urgent need to use non-standard ways to strengthen the bases. In many cases, the geotechnical situation is aggravated by the presence of weak underlying layers with unstable physical and mechanical characteristics in engineering-geological sections. When strengthening such bases with the help of traditional piles, the latter can get negative friction, which significantly reduces their bearing capacity on the ground, sometimes reaching zero values. This may lead to additional precipitations of the objects being constructed and constructed in the zone of geotechnical influence. The use of ERT piles in most cases successfully solves many complex geotechnical problems.

Sign in / Sign up

Export Citation Format

Share Document