Evaluation of vertical and lateral bearing capacity mechanisms of pile foundations using X-ray CT

The article discusses issues related to the construction of pile foundations of buildings and structures, including bridges and other transport facilities. The development of the construction industry contributes to the improvement of pile Foundation construction technology and a significant reduction in economic costs. Improving the design and technology of pile foundations is one of the main tasks in the field of transport construction. The effectiveness of pile foundations is due to the more complete use of the bearing capacity of the soil base and the strength of the Foundation elements. One of the disadvantages of the pile foundation is the low bearing capacity of the soil on the side surface of the pile. The proposed solution is based on the device along the longitudinal axis of the pile rigidly fixed, multi-pass continuous inclined edges having the shape of a plate, and faces adjacent to the side surface of the tubular steel barrel.

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Bearing capacity of piles in a reinforced by pressure cementation soil massif

E3S Web of Conferences ◽

10.1051/e3sconf/202127403023 ◽

2021 ◽

Vol 274 ◽

pp. 03023

Author(s):

Ildus Shakirov

Keyword(s):

Bearing Capacity ◽

Cement Mortar ◽

Pile Foundations ◽

Soil Resistance ◽

Injection Parameters ◽

Pressure Injection ◽

Soil Stress ◽

Soil Compression ◽

Reinforcement Design ◽

Surface Increase

Studies of the piles bearing capacity after strengthening soil by cement mortar pressure injection were carried out to determine pile foundations bearing capacity increasing patterns in a result of soils cementation. Depending from the volume and cement mortar technological injection parameters, the soil stress state around the pile changes, additional pile-soil compression occurs and the friction along the lateral surface increase, as well as the soil resistance under the pile bottom end. Cementation effect on the pile bearing capacity for different injectors location and the number of piles in the foundation were determined by tests. The research results can be used in the pile foundations reinforcement design in conditions of reconstruction with increasing loads on the foundations.

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Experimental Study of the Bearing Capacity of Helix Pile Foundation

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/921/1/012064 ◽

2021 ◽

Vol 921 (1) ◽

pp. 012064

Author(s):

P R Sangle ◽

L Febriani

Keyword(s):

Experimental Study ◽

Bearing Capacity ◽

Pile Foundation ◽

Triple Helix ◽

Double Helix ◽

Peat Soil ◽

Pile Foundations ◽

Hard Soil ◽

Supporting Structures ◽

Single Helix

Abstract The use helix pile foundations in supporting structures on peat soil has became a challenge for road infrastructure. The helix pile foundation is an alternative for substituting the pile foundation if hard soil is located too far from the surface. Therefore, in this study we examine the bearing capacity of the helix pile foundation on peat soil, including analyzing the effect of the number of helix plates on the bearing capacity of the peat soil. The type of foundation used is a helix pile foundation with a single blade, double blades and triple blades. From the results of the research the bearing capacity of helix double is 35% greater than the bearing capacity of a single helix, the value of triple helix bearing capacity is 25% greater than the double helix and 70% of the single helix. The more number of helix plates used, the greater the bearing capacity of the piles given.

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KOMPARASI KINERJA ALAT PILE DRIVING ANALYZER DAN SOFTWARE CAPWAP DALAM MENGHASILKAN DAYA DUKUNG ULTIMIT PONDASI TIANG

Jurnal Darma Agung ◽

10.46930/ojsuda.v28i3.802 ◽

2020 ◽

Vol 28 (3) ◽

pp. 378

Author(s):

Rasdinanta Tarigan

Keyword(s):

Bearing Capacity ◽

Pile Foundation ◽

Soft Soil ◽

Performance Comparison ◽

Ultimate Bearing Capacity ◽

Pile Foundations ◽

Pile Driving ◽

Analysis Program ◽

Wave Analysis ◽

The Difference

Buildings that stand on soft soil usually use a pile foundation. Testing the ultimate bearing capacity of pile foundations in the field is a Pile Driving Analyzer (PDA) tool. Besides being inexpensive to test, the results can also be known quickly. This tool is supported by a software called CAPWAP (CAse Pile Wave Analysis Program).In this paper, a performance comparison of the Pile Driving Analyzer (PDA) and CAPWAP (CAse Pile Wave Analysis Program) software will be presented in producing the ultimate bearing capacity of pile foundations. The results of both will be analyzed in such a way that the causes of the differences in the performance of the Pile Driving Analyzer (PDA) and the CAPWAP software are known.The results obtained show that the performance of the Pile Driving Analyzer (PDA) tool will not be optimal if the energy transferred to the pile foundation is too small. The energy given by the hammer when struck must be in the range of 1% - 2%, if it is smaller then the performance of the tool in producing the ultimate bearing capacity will not be representative. The difference in the ultimate bearing capacity between the PDA device and the CAPWAP software for energy transferred to the pile foundation (EMX) under the specified energy standard is 10.71% - 33.23%. Meanwhile, energy that meets the specified standards has a value between 0.24% - 1.80%.

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Calculation of Bearing Capacity and Deformation of Composite Pile Foundation with Long and Short Piles in Loess Areas

Advances in Civil Engineering ◽

10.1155/2020/8829779 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Tianzhong Ma ◽

Yanpeng Zhu ◽

Xiaohui Yang

Keyword(s):

Theoretical Calculation ◽

Bearing Capacity ◽

Pile Foundation ◽

Frictional Resistance ◽

Operating Conditions ◽

Neutral Point ◽

Pile Foundations ◽

Single Pile ◽

Deformation Control ◽

Composite Pile

In order to calculate the bearing capacity and settlement deformation of composite pile foundations with long and short piles in collapsible loess areas, the theoretical approximate solution was used to obtain the location of the neutral point of single piles. Additionally, based on the equation to calculate the bearing capacity of multielement composite foundations, a method considering the negative frictional resistance was proposed for calculating the bearing capacity of composite pile foundations with long and short piles. Based on the shear displacement method and the principle of deformation control, an equation to calculate the displacement and deformation of a composite pile foundation was presented. A model test with different operating conditions, i.e., a single pile, four piles, and eight piles, was designed to verify the proposed calculation methods. The results show that the location of the neutral point has a significant influence on the single-pile negative frictional resistance, and the neutral point ratio of the calculation meets the value range of the practical project. When the load at the top of the pile is relatively small, the experimental curve is consistent with the theoretical calculation curve, whereas when the load is comparatively large, the theoretically calculated displacement increase at the top of the pile is greater than the measured one. Under the premise that the theoretical calculation is in good agreement with the results, the theoretical value is larger than the actual value. And it contributes to strengthening engineering safety.

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Experimental Study on Static Load of Large-Diameter Piles in Nonuniform Gravel Soil

Advances in Civil Engineering ◽

10.1155/2020/6291826 ◽

2020 ◽

Vol 2020 ◽

pp. 1-15

Author(s):

Baoyun Zhao ◽

Xiaoping Wang ◽

Mijia Yang ◽

Dongyan Liu ◽

DongSheng Liu ◽

...

Keyword(s):

Bearing Capacity ◽

Pile Foundation ◽

Static Load ◽

Large Diameter ◽

Skin Resistance ◽

Geological Structure ◽

Load Test ◽

Pile Foundations ◽

Gradual Change ◽

Test Pile

With the development of tourism, the number of multistorey buildings in mountain areas is increasing gradually, and the requirements of the form and bearing capacity of foundation in landslide areas are getting more demanding than ever. In-situ testing of rock and soil mass in slope area has important practical significance for improving the stability of building foundation. Taking a project in Baishi Mountain located in southwest of China as an example, firstly, the geological structure and mechanical properties of soil are analyzed. Then, two types of pile foundations, i.e., empty-bottom pile foundations and solid-bottom pile foundations, are designed based on the characteristics of the geological structure for carrying out the static load test on pile foundation. The test results are as follows: (a) the load settlement curve (Q-S) of the empty-bottom test pile shows a steep drop, while the Q-S curve of the solid-bottom test pile shows a gradual change, showing that the end-bearing friction pile’s property and the ultimate bearing capacity of the solid-bottom pile are higher than those of the empty-bottom pile. (b) The maximum lateral friction of the four test piles is 139.158 kPa, 148.015 kPa, 150.828 kPa, and 154.956 kPa, respectively. (c) The shaft skin resistance under ultimate load is coming close to the maximum value, and the maximum values are 9.792 mm, 7.939 mm, 9.881 mm, and 14.97 mm, respectively. Research results can serve as design bases for the pile foundation of multistorey buildings located in landslide areas of Baishi Mountain in the southwest of China and also as references for the engineering application of pile foundation in similar geological fracture areas.

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