Estimation of Ultimate Bearing Capacity of Footings on Soft Clay from Plate Load Test Data Considering Variability

2018 ◽  
Vol 49 (2) ◽  
pp. 170-183 ◽  
Author(s):  
Parbin Sultana ◽  
Ashim Kanti Dey

This paper discusses the Ultimate Bearing Capacity of a stabilized soil by using the fly ash, stone dust and rubber powder for design of a pavement. This paper will help in utilization of locally available waste materials to reuse in the subbase and subgrade layers of pavement. Rubber powder is a waste byproduct generated from the recycling of tires, and is not so easy for degradable, and hence leads to release of harmful gases when it tends to burn. Stone dust is a locally available waste generated product from quarries. The generation of stone dust is increasing day to day in large quantity. The huge quantity of stone dust storage amount will affect the quality of soil. Fly ash is waste combusted coal ash powder generated from the steamers of coal boilers with the burning of fuel gases together. In the sub grade layer the soil is mixed in different proportions with stone dust for hard foundation. In the sub base layer the soil is stabilized with the combination of rubber powder and fly ash. When the rubber powder and fly ash, mixed with water for compaction generates a bond between the soil particles to settle the air fields. In this paper various percentages of rubber powder, stone dust and fly ash with different samples for pavement is layered, and after that plate load test is conducted upon it.


2020 ◽  
Vol 857 ◽  
pp. 179-187
Author(s):  
Mohammed Kadum Fakhraldin

Gypseous considered as problematic soils also gypseous soils are distributed all over the world, as well as in large areas of Iraq, including Al- Najaf city. Gypseous soils are characterized by high strength in dry conditions, but they collapse due to water infiltration process under constant head conditions. In this research, a field study investigates gypseous soils and the effect of soaked state on the bearing capacity and settlement of the gypseous soils are investigated. A site with a high percentage of gypsum (about 25%) was selected to perform plate load tests. The test was carried out in a natural and soaked state on the gypseous soils by plate load test with time-dependent. The results show the ultimate bearing capacity of gypseous soil from plate load test are decrease under the soaking condition and maximum settlement increase. The angle of internal friction (ø) of gypseous soil we obtained from the direct shear test is 47.620 for natural soil. The ultimate bearing capacity of gypseous soil was calculated from the Terzaqhi’s equation and the high difference between field tests and theoretical results.


Author(s):  
Gizem Misir ◽  
Mustafa Laman

This study is concerned with the bearing capacity of circularfootings on a granular fill layer above a soft clay soil. Theresults of an extensive series of laboratory and field tests wereused to define an empirical equation. This is generally doneby estimating the dependent variable (e.g. bearing capacity)based on the independent variables (e.g. granular fill layerthickness, soil and footing parameters and settlement ratio).A logarithmic model has been developed by using regressionanalysis to estimate the bearing capacity of a circular footingresting on granular fill at any settlement ratio, using allpossible regression techniques based on 342 field test data, toselect the significant subset of the predictors. The results indicatethat the logarithmic model serves a simple and reliabletool to predict the bearing capacity of circular footings placedon a granular fill with different thicknesses above a soft claysoil. And also, the validity of the developed formulation wasverified with different plate load test results from literature.


2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
A. Hemalatha ◽  
N. Mahendran ◽  
G. Ganesh Prabhu

The experimental investigation on the effects of granular fill and geogrid reinforced granular fill on the behaviour of the static liquefaction potential of the subsoil is reported in this study. A series of plate load test were carried out with different thickness of the granular fill, number of geogrid layers, and size/dimension of the footing. The test results were presented in terms of bearing capacity and subgrade modulus for the settlement ofδ10,δ15, andδ20. The experimental results revealed that the introduction of granular fill significantly increases the bearing capacity and effectively control the settlement behaviour of the footing. The introduction of geogrid in granular fill enhanced the Percentage of Control in Settlement and Bearing Capacity Ratio by a maximum of 328.54% and 203.41%, respectively. The introduction of geogrid in granular fill interrupts the failure zone of the granular fill and enhances the subgrade modulus of the footing by a maximum of 255.55%; in addition subgrade modulus of the footing was increased with an increase in the number of geogrid layers. Based on the test results it is suggested that the footing with large size has beneficial improvement on the reinforced granular fill.


2011 ◽  
Vol 250-253 ◽  
pp. 2271-2275
Author(s):  
Cheng Wang ◽  
Qi Zhang

Vertical static load test is widely used in the determination of pile bearing capacity, the mathematical model used to fit test pile data in determining the bearing capacity is essential. From the perspective of analytic geometry, the paper analyzes the traditional method of hyperbola, of which the asymptotic line of equilateral hyperbola was used to determine the ultimate bearing capacity. By extending the equal-axed conditions, a more general form of hyperbolic equation is derived and feasibility of such method is also analyzed, which indicates that the maximum point of curvature in such hyperbolic curve can determine the ultimate bearing capacity and such method is proved to be reasonable in practical projects.


Author(s):  
Qasim Al-Obaidi ◽  
Ali Al-Shamoosi ◽  
Azad Ahmed

2018 ◽  
Vol 13 (2) ◽  
pp. 87-93
Author(s):  
Muhammet Vefa Akpinar ◽  
Erhan Burak Pancar ◽  
Eren Şengül ◽  
Hakan Aslan

In this study effectiveness of lime stabilization and geocell reinforcement techniques of roads was investigated for low bearing capacity subgrades. For this purpose, a large-scale plate load test was designed and used. Clayey soil with high moisture content was reinforced with different percentages of hydrated lime (5%, 10%, 15% dry weight of the soil). The deflection and stress results indicated that lime stabilization or geocell reinforcement alone did not significantly increase subgrade reaction coefficient and bearing capacity values. Promising results were obtained on stabilization of weak subgrade when both techniques were used together. It was determined that cellular reinforcement increased the reaction modulus coefficient value and bearing capacity of the subgrade soil by more than 15% compared to the lime stabilization.


2013 ◽  
Vol 341-342 ◽  
pp. 1449-1452
Author(s):  
Qing Dun Zeng ◽  
Fang Liu

Various new type scaffolds have been introduced and developed in China. They are novel in structure and economic in material, but their security and reliability can not be ignored. This paper introduced a new chained formwork support frame with nine upright tubes and many cross-braced connections. Firstly, the load test of the support frame was performed in order to observe the failure process and to determine the ultimate bearing capacity. Then, the strength and stability of both single upright tube and a cross-braced rod were checked according to the existing specifications on scaffolds. Finally, a finite element software ANSYS was used to establish a solid model for the support frame. The structural stability was analyzed and the ultimate bearing capacity was calculated. The comparison between the computational and experiment results was carried out. The results show that the ultimate bearing capacity of the new chained formwork support frame is controlled by the structural stability.


1998 ◽  
Vol 35 (5) ◽  
pp. 801-810 ◽  
Author(s):  
Ping-Sien Lin ◽  
Li-Wen Yang ◽  
C Hsein Juang

This paper presents the result of plate-load tests conducted on a gravelly cobble deposit in Taichung Basin, Taiwan. The geologic formation of the gravelly cobble deposit makes it very difficult to obtain large undisturbed samples for laboratory testing. These field tests provide an opportunity to examine the applicability of existing theories on bearing capacity and subgrade reaction in this geologic formation. The modulus of subgrade reaction is of particular importance in the local practice of designing high-rise buildings on mat foundations. The results of the plate-load tests on this soil deposit are analyzed and discussed.Key words: plate-load test, gravelly cobble deposit, modulus of subgrade reaction, bearing capacity.


2021 ◽  
Vol 13 (23) ◽  
pp. 13166
Author(s):  
Xusen Li ◽  
Jiaqiang Zhang ◽  
Hao Xu ◽  
Zhenwu Shi ◽  
Qingfei Gao

Prestressed high-strength concrete (PHC) pipe piles have been widely used in engineering fields in recent years; however, the influencing factors of their ultimate bearing capacity (UBC) in multilayer soil need to be further studied. In this paper, a static load test (SLT) and numerical analysis are performed to obtain the load transfer and key UBC factors of pipe piles. The results show that the UBC of the test pile is mainly provided by the pile shaft resistance (PSR), but the pile tip resistance (PTR) cannot be ignored. Many factors can change the UBC of pipe piles, but their effects are different. The UBC of the pipe pile is linearly related to the friction coefficient and the outer-to-inner diameter ratio. Changes in the pile length make the UBC increase sharply. Low temperatures can produce freezing stress at the pile–soil interface. The effect of changing the Young modulus of pile tip soil is relatively small.


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