Settlement Of Pile Foundation Research Articles

Method for calculating the settlement of ring pile foundations of tanks

Annotation. A method for calculating the settlement of ring pile foundations of reservoirs on clay soils is considered. The proposed method provides for a separate calculation of the settlement of the central part of the tank (bottom draft) and a reinforced concrete ring pile foundation arranged along its edges (foundation ring settlement). The bottom of the tank is not rigidly connected to the ring foundation. The method of M I Gorbunov-Posadov and others for a flexible round foundation on a linearly deformable base was used. When calculating the settlement of the pile ring, the method of A A Bartolomey was used for strip pile foundations. The work takes into account the assessment of the additional settlement of the bottom and pile ring caused by repeated loading and unloading of the base of the tanks.

On the Influence of Pile Foundation Settlement of Existing High-Rise Buildings on the Surrounding Buildings

Pile foundation settlement is a kind of foundation form. In recent years, because of the increasing population and economic development in China, high-rise buildings have emerged in people’s vision. Due to the development of engineering construction, the type and technology of pile foundation, as well as the control and detection of the single pile and pile group have been greatly improved. In view of the influence of pile foundation settlement on the surrounding environment of high-rise buildings, this paper mainly studies from the angle of single pile settlement and pile group settlement. According to the construction method of pile foundation, the static pressure sinking pipe cast-in-place pile can produce soil squeezing effect in pile foundation construction. The experimental analysis was carried out. According to the engineering example, finite element numerical simulation is used to analyze the influence degree of pile foundation settlement on adjacent buildings with and without raft, and the feasibility and correctness of numerical simulation are analyzed by comparing the simulation results with the measured values. This paper mainly studies the influence of pile foundation settlement of high-rise buildings on surrounding buildings from the aspects of problems and solutions.

Analysis study of soil bearing capacity and settlement of single pile foundation based on N-SPT data

Foundation is a very important structural element in a building. The bearing capacity of the soil is the support for the foundation, where a foundation is defined as a most basic part of the construction of a building that transmits the load originating from the weight of the building itself and the load acting on the building to the surrounding ground. The purpose of this research is to determine the bearing capacity of the foundation and the settlement of a single pile that occurs and to determine of the size of ship’s collision force against the building. The foundation used in the construction of the Sultan Suriansyah Mosque Port is a 45 cm diameter pile foundation. The calculation of bearing capacity of a single pile was carried out using the Mayerhoff method based on the N-SPT results of 399.802 tons. The settlement of a single pile foundation using the Semi Empirical Method is 0.036 m with an allowable drop of 0.045 m. The collision force of the ship against the Port is 0.0032 tons.

Study on Settlement and Deformation of Urban Viaduct Caused by Subway Station Construction under Complicated Conditions

With the rapid development of urbanization, the speed of constructing urban underground space and ground foundation engineering is accelerated. With the shortage of land resources, the distance between underground engineering and surface engineering is getting closer and closer, and the contradictions and problems between projects are becoming more and more serious. Based on the new subway station, this paper passes the existing urban viaduct in a short distance. The settlement and deformation of pile foundation and buildings caused by the excavation of the subway station is studied by using ROCSCIENCE software and site monitoring method. The potential risk sources around the station are pile foundations 18.5 m away, residential buildings 15 m away, storm water pipes 7.3 m away, and high‐pressure gas pipes at 5.6 m. According to the construction requirements of pile foundation settlement deformation during metro station excavation, we set up construction standards. The settlement of the buildings and pipelines around the metro station should not exceed 3 mm, and the horizontal displacement should not exceed 2 mm. The diaphragm wall is adopted to surround the subway station, and the ground is reinforced by advanced grouting. The results show that, during the excavation of the foundation pit of the metro station, the ground and the building will have obvious settlement deformation and the depth of deformation can reach 9 mm, which is more than the allowable value. The settlement deformation of the ground and the surrounding buildings can be controlled within 3 mm by strengthening the foundation pit support and ground advance‐grouting reinforcement. The control of construction deformation can meet the construction requirements.

Ratio of long-term settlement to immediate settlement for piled raft on soft clay

A simplified analytical approach based on the non-linear pile–soil interaction model under vertical load is employed to analyse settlement of piled raft foundations. The accuracy of the simplified method is verified through comparisons with the results from previous research. Furthermore, according to the calculation results of various pile configurations, a simple empirical equation for estimating long-term settlement of a piled raft foundation is proposed. The prediction equation is validated through comparison with published cases. The comparison results show that the ratio of long-term settlement to immediate settlement increases linearly with the square root of the number of piles (at the same pile spacing), whereas the influence of the length/diameter ratio of the pile is small. The settlement ratio is approximately 2 for a piled raft foundation, and 1·5 for a raft or box foundation, and this may be useful for preliminary assessment of the long-term settlement behaviour of piled raft foundations.

Analysis of the influence of pile foundation settlement of high-rise buildings on surrounding buildings

In order to explore the impact of pile sinking on surrounding buildings in existing high-rise buildings, in this study, the influence of pile foundation settlement on surrounding buildings of existing high-rise buildings is studied and analyzed by building models. Firstly, the theory of pile-soil interaction is introduced. The theoretical calculation of pile foundation settlement is simplified by existing theory and practical engineering calculation, and the settlement value of surrounding buildings is calculated. Then, the simulated experimental area model is established. Finally, the influence of pile foundation settlement on the surrounding buildings with and without raft in foundation is explored. The results show that under the condition of pile diameter and other conditions being the same, with the increase of pile length, the pile foundation settlement of existing high-rise buildings has less and less influence on the surrounding buildings. When the pile length increases to 22 m, the pile foundation settlement of existing high-rise buildings has little impact on the surrounding buildings; at the same time, under the same pile length, the settlement of pile foundation of existing high-rise buildings without raft has less influence on the surrounding buildings than that of pile foundation with raft. This study is of guiding significance to the construction of buildings around high-rise buildings in China.

REVIEW OF BEARING CAPACITY AND SETTLEMENT OF PILE FOUNDATION IN PORT INFRASTRUCTURE

ABSTRACTThe rapid infrastructure development is one of the indicators on the country economic progress. Indonesia as one of the largest archipelagic countries in the world, should be prioritized the port infrastructure to support the maritime. One of the government’s solutions is infrastructure development of Kuala Tanjung port. This research analyzed bearing capacity and settlement of single and group pile foundation on port infrastructure of Kuala Tanjung so it is known that the port is safe to use. The data used are Standard Penetration Test data with soil stratigraphy that is clay and sand. The type of foundation used is Concrete Spun Pile 1000 mm and 600 mm with a pile length of 36 meters. The data are then analyzed by manual calculation and Allpile 6.5E program based on Reese method and methods such as Vesic and Converse-Labarre. The results showed that single pile foundations of 1000 mm and 600 mm each had allowable capacity (Qall) 492.78-538.81 ton and 110.65-128.31 ton, with vertical load (Q) of 330.90 ton, settlement 0.56-1.17 cm and 3.32-3.64 cm, lateral deflection 27.50 cm and 94.90 cm. While the 1000 mm and 600 mm pile group foundations respectively have Qall 8717.31-10796.29 tons and 2059.25-2566.32 tons, with Q of 6618 tons, settlement 0.56-1.68 cm and 3.32-3.64 cm, lateral deflection of 2.49 cm and 19.49 cm. The conclusion of the research indicates that the safe pile foundation used is 1000 mm group pile foundation. Keywords: Bearing Capacity; Foundations; Pile Foundation; Port Infrastructure; Settlement

Behavior of Group of Plugged and Unplugged Pipe Piles in Soil Containing Cavities

The present study examines the effect of cavities on the pipe pile foundation settlement and capacity subjected to compressive axial loads and embedded in sandy soil. By inserting a prototype of cavity which is placed adjacent to the pile at different locations that lie at horizontal spacing between pile and cavity center to center defined by (X) and cavity depth from the soil surface by cavity depth (Y), the variation in cavity location was studied for all laboratory tests. The presence of cavity reduces the pile load capacity by different rates depending on its location. In group piles with of L/D = 15 with cavity at Y/L = 1 and X/D = 1.5, 2.5, the reduction is between (6.1% to 26%).

Calculation of the settlement of pile foundations taking into account the influence of soil liquefaction

Pile foundations are considered one of the most common foundation solutions for the construction of buildings and structures in difficult geotechnical conditions, including in seismic areas. However, during earthquakes specific processes often occur that negatively affect the interaction of piles with the surrounding soil. Soil liquefaction is one of the most difficult problems in geotechnics. Many historical cases show that buildings and structures on pile foundations are collapsed completely when the surrounding soil liquefies. One of the reasons is the increase in settlement of the foundation after soil liquefaction.Unlike the liquefaction potential assessment, or liquefaction-induced settlement of structures on shallow foundations, which are discussed by many researchers, the settlement of pile foundations after soil liquefaction has not been studied extensively. This paper presents the calculation of the settlement of pile foundations in different cases, with and without taking into account the influence of soil liquefaction, based on the hypothesis that the additional downward loads due to self-compaction of the liquefiable soil layers have an effect on piles. The analysis method in this study refers to the finite element method via PLAXIS 3D software. Finally, a brief comparison of the calculation results in the different considered cases is presented. The comparison shows how much the foundation settlement can increase if the influence of soil liquefaction is taken into account based on the suggested hypothesis. This paper provides a useful calculation and importance of further researches of liquefaction-induced settlement of pile foundations for seismic design.

An Analysis of Static Load Test on Sinngle Square Pile of 50 x 50 cm2 Using Finite Element Method in Multy-Storey Building Project , Pluit, North Jakarta

Planning a foundation for a high building and carrying a large construction burden, must be carried out with a correct, thorough and comprehensive analysis, so that a foundation design is able to carry the burdens that works on it and can carry the loads it receives to ground beneath it safely. This study analyzed the capacity of bearing capacity and the settlement of the hydraulic stressed pile foundation of prestressed concrete square pile of 50 x 50 cm2 in cross section of single pile or group pile. The research used empirical method, finite element method program and compared the results with the interpretation of axial static loading test on the Multy-Storey Building Project in Pluit, North Jakarta. The analysis used soil investigation and laboratory study and used 2D and 3D finite element methods by Mohr-Coulomb and Soft soils models. The result of the analysis on the ultimate bearing capacity of hydraulic stressed pile foundation with empirical method of Meyerhof gave the highest value using SPT data at DB1 borelog point of 655.23 tons, and the lowest was the result of interpretation of Loading Test by Davisson’s method of 260.00 tons. The ultimate bearing capacity required by ASTM D1143-81 (1989) for the Static Axial Loading Test is 300 tons (200% of working load), while the interpretation of the Davisson’s Loading Test method (260.00 tons), Chin (267,86 tons) and Mazurkiewicz (267.00 tons), none of which have fulfilled the requirements for carrying 150 tons of working load. The lateral bearing capacity of Broms method was 16,14 tons which was the strength of the pile material against lateral loads. Whereas for the bearing capacity of the group pile ( 6 points in one pilecap) the lowest efficiency of 0,734 from the Converse-Labarre Equation and the highest efficiency of 0,805 from the Los Angeles Group Action Equation was obtained. For 200% of the planning load of 150 tons, that is 300 tons, the settlement of the single pile which occurred from 2D finite element method program were 18,00 mm and 15,63 mm for 3D while the results of the Loading Test was 15,00 mm. The results of the analysis of Loading Test settlement was more realible.

Optimization Method of Reducing the Differential Settlements of Piled Raft Foundations Based on Pile‐to‐Pile Interaction Theory

In order to reduce the differential settlement of piled raft foundations, an optimization method based on pile‐to‐pile interaction theory is proposed in this paper, which translates the problem of pile‐to‐pile interaction (PPI) in pile groups into that in single piles using the interaction factor method. The pile lengths were adjusted via the relationship between load, settlement, and the length of single piles during the optimization design. ANSYS software, in conjunction with nonlinear elastic soil model, is used to analyze piled raft foundation models. Two cases with different safety factors that suffer different kinds of surface loads (uniform load and nonuniform load) are used to verify this method. The differential settlements of the raft in different cases are all reduced by nearly or more than 80% after optimization design. The results show that the optimization method proposed in this paper has high efficiency and stability. This study can help practicing engineers optimize the pile lengths in pile groups to satisfy higher differential settlement requirements.

THE FORECAST OF LONG-TERM SETTLEMENT OF THE PILE ON SANDSTONES AND CLAYSTONES OF THE PERMIAN AGE

In the article the problem of ensuring the long-term settlement of single piles on claystones and sandstones are reviewed. Incorrect assessment of stabilized settlement of pile foundation can lead to an emergency situation. At the present time for prediction of foundation settlement is widely used finite element method, implemented in a variety of software systems. The aim of the study was to select the optimal model in the software package Plaxis 3D to forecast settlement of driven and bored piles on claystones and sandstones. The authors solved the following tasks: 1) review of the knowledge of long-term settlement of single piles and pile foundations on claystonese and sandstones is performed; 2) the technique is described and numerical experiments are performed in the software package Plaxis 3D for modeling the settlement of a single driven pile and bored pile on claystones and sandstones with varying degrees of weathering; 3) comparison of the results of numerical experiments with long-term field tests of piles on claystones and sandstones is performed; 4) findings from the study are formulated. Numerical experiments of modeling in the software package Plaxis 3D work of driven piles on claystones and sandstones showed that the introduction of soil compaction zones around the driven pile into the calculation scheme makes it possible to obtain close values to long-term settlement of full-scale piles. The authors recommend using the Hardening soil model to predict the work of a driven pile on claystones and sandstones and the Linear-Elastic model to simulate the work of a bored pile on claystones and sandstones. For highly weathered claystones and sandstones soil models need to be corrected for numerical calculations in Plaxis 3D, since the use of the Hardening soil and Linear-Elastic models showed underestimated settlement values in relation to field tests of driven piles.

Analysis of Comparison of Calculation Methods for Downdrag of Single Pile

The problem of negative skin friction has acquired great importance for the circles of civil engineering over that last few decades. It aims to understand the mechanisms of pile-soil interaction, define more adequate analytic methods for the load transferand and ensure the bearing capacity of pile foundation. But for the complexity of problems, there are some issues that have not been well solved in engineering practice.In order to avoid the failure of pile body, the uneven settlement of pile foundation and other engineering disasters, the researches of downdrag have been carried out since 1965. And engineers have proposed a number of calculation formulas for the downdrag of single pile, yet the calculation results differ sharply on account of the respective applicability and limitation of these formulas.This paper introduces several common calculation methods of downdrag on single pile and recommends diverse calculation situations in self-weight collapsible loess area. In this paper, some calculation methods based on limit analysis method will be compared from different angles and the applicable conditions, advantages and disadvantages, etc. are also discussed to provide reference for practical engineering design.

EXPERIMENTAL STUDY OF MODEL PILE FOUNDATIONS IN SEASONALLY FREEZING SOIL GROUND

The bearing capacity and settlement of pile foundation were greatly influenced by the temperature variations of soil ground around pile foundation. This paper presented a short report about laboratory static load tests by model precast concrete piles (cross-section 4 × 4 cm and length of 60 cm) in seasonally freezing soil ground. The depth of frozen soil was 10 cm, temperature -5℃, -10℃, +20℃. There were many factors influencing on pile foundations, such as ice in the ground, low temperatures and moisture of the soil. A series of tests of model piles in seasonally freezing soil ground were carried out, the results of bearing capacity of pile foundations and a settlement were compared. The results of the experiments were shown in charts. By application of numerical modeling the pile and soil base interaction vertical deformation in thermal changes of soil ground, the different settlement of piles. Modeling of thermal conditions of soils in software in accordance with real conditions on the construction site of Kazakhstan, analysis,and comparison of the obtained results ofthe settlement of pile foundations at low temperatures are presented in the paper.

Three - dimensional Numerical Simulation and Validation of Load-settlement Behaviour of a Pile Group under Compressive Loading

Settlement of pile foundation is one of the controlling pile design parameters and its numerical simulation is one of the techniques widely used to predict the settlement behaviour of piles. This study was on the settlement behaviour of a pile group located in silty-sand deposits using the finite element (FE) approach which is based on the static pile load test. Three different types of analyses were investigated: (1) a linear elastic (LE) analysis in which the soil was assumed to be linear elastic, (2) a complete nonlinear analysis in which the soil adjacent to the pile shaft as well as the soil between the piles were modelled using the Mohr Coulomb (MC) or hardening soil (HS) model, and (3) a combined analysis in which the soil close to the pile shaft was modelled using the HS model while the soil in the remaining area was modelled using the LE or MC model. Numerical results obtained for the load-settlement behaviour of the pile group were validated using the popular RATZ analytical approach. The results of the FE analysis suggest that incorporating a nonlinear zone of soil close to the pile shaft as an interface and leaving the soil beyond this zone as linear elastic give a more reasonable estimation and a much better prediction of the pile group settlement. It is also suggested that for a typical pile group, a nonlinear interface of thickness equal to the pile diameter and extending from the pile shaft to the edge of the zone would be sufficient to capture the load transfer mechanism. The group settlement ratio predicted in this study is in good agreement with the findings made in the previous studies.

Assessment the effect of pile intervals on settlement and bending moment raft analysis of piled raft foundations

Application the pile group foundation to reduce overall settlement of the foundation and also avoid a very fruitful settlement of foundations, inconsistent was carried out. In such a case, in event that the Foundation, not as a mere pile group, which as a system consisting of a broad foundation with pile Group, economic design criteria will be provided in spite of high safety. A new approach in the design of the Foundation can be introduced as the piles are just a tool to improve the parameters of soil hardness; that it can work with detachable piles from raft. Centralized arrangement of piles as the most optimal layout of piles in reducing inconsistent settlement, which is the lowest value of resulting layout in this differential settlement. Using the combination of piles connected and disconnected to form the raft, bending moment created in the raft is reduced. It also concentrated arrangements have greatest effect in reducing amount of moment applied to the raft.

Settlement of Residential Houses Supported by Piled Foundation Embedded in Expansive Soil

The damage has occurred on residential houses built on expansive soils. The weight of the walls and roof of the houses is transferred onto pile foundations through suspended tie beams and columns, respectively. The typical pile used to support the house was 30cm in diameter and it was penetrated into the depth of 600cm. The slabs or floors were rested on the fills. This study was conducted to determine all potential sources that initiated the settlement and damages to the houses. Site investigation to each and every houses that experienced settlement and damages was conducted to gather and inventory the pattern of the cracks or damages. The result of site investigation showed that there were no damages induced by swelling, but the settlements and cracks were triggered by settlement, instead. It was also noticed that the settlement of piled foundations located on the area that susceptible to the water infiltration relatively larger than those piled foundation in the covered area. Therefore, it was concluded that, based on the analysis, the damages which occurred on the residential ordinary houses were mainly caused by the settlement of the piled foundations and the fills due to the soil softening.

Prediction of elastic settlement of rectangular piled raft foundation

A FE – BE coupling technique is used in the present study for prediction of elastic settlement of rectangular piled raft foundations. The raft is idealised as a thick plate freely resting on soil medium, which is idealised as a semi-infinite, isotropic and homogeneous elastic half -space. The plate and the half- space are two separate models in unilateral and frictional contact at the interface. Pile is idealised as a spring of equivalent stiffness, obtained from simplified approach based on elastic theory assuming it to be a shaft in the half-space. Boundary element method is employed to determine the soil stiffness matrix by inverting the soil flexibility matrix, using Mindlin’s solution for a point load in half-space as a fundamental solution. Finite element method is employed to determine the raft stiffness matrix based on Mindlin’s plate bending theory, which allows transverse shear deformation. Transformation of the boundary element matrices are carried out to make it compatible for coupling with plate stiffness matrix obtained from finite element method. Combined stiffness matrix of the soil-pile-raft system is obtained by summing up the stiffness of the soil-raft system and the stiffness contribution of the piles at selected locations. A computer programme is developed, based on the procedure describe above, in which discretisation is automatic and requires very nominal data input. Effect of pile parameter on settlement of a piled raft system subjected to uniformly distributed load is studied for different number and configuration of piles to demonstrate the efficacy of piled raft system in reducing settlement.

A computational method for post-construction settlement of high-speed railway bridge pile foundation considering soil creep effect

Based on reasonable assumptions that simplified the calculational model, a simple and practical method was proposed to calculate the post-construction settlement of high-speed railway bridge pile foundation by using the Mesri creep model to describe the soil characteristics and the Mindlin-Geddes method considering pile diameter to calculate the vertical additional stress of pile bottom. A program named CPPS was designed for this method to calculate the post-construction settlement of a high-speed railway bridge pile foundation. The result indicates that the post-construction settlement in 100 years meets the requirements of the engineering specifications, and in the first two decades, the post-construction settlement is about 80% of its total settlement, while the settlement in the rest eighty years tends to be stable. Compared with the measured settlement after laying railway tracks, the calculational result is closed to that of the measured, and the results are conservative with a high computational accuracy. It is noted that the method can be used to calculate the post-construction settlement for the preliminary design of high-speed railway bridge pile foundation.

3D Finite Element Analysis on Behaviour of Piled Raft Foundations

This paper highlights settlement behaviour of piled raft foundation by 3D finite element analysis through Plaxis 3D Foundation program. The effects of pile number, pile length, pile layout and pile spacing on the behaviour of piled raft foundation were studied. The numerical results show that: Piled raft foundation has much more efficency to reduce settlement than that of traditional raft foundation. The value of vertical defomation decreases as the result of the increase of pile number, pile length, pile spacing and vice versa. Pile layout has significant effect on both value and location of maximum settlement of piled raft foundation.