scholarly journals Calculation Approach for Lateral Bearing Capacity of Single Precast Concrete Piles with Improved Soil Surrounds

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Guangyin Du ◽  
Anhui Wang ◽  
Liye Li ◽  
Dingwen Zhang
Keyword(s):  
Bearing Capacity ◽  
Precast Concrete ◽  
Ground Improvement ◽  
Bending Moments ◽  
Finite Element Analyses ◽  
Reinforcement Effect ◽  
Lateral Capacity ◽  
Concrete Piles ◽  
Soft Ground Improvement ◽  
Lateral Deflections

Precast concrete (PC) piles with cement-improved soil surrounds have been widely used for soft ground improvement. However, very few calculation approaches have been proposed to predict the lateral bearing capacity. This study aims at investigating the lateral capacity of a single PC pile reinforced with cement-improved soil through a series of 3D finite element analyses and theoretical studies. It is revealed that application of cement-improved soil around the PC pile can obviously reduce the induced lateral deflections and bending moments in the pile and can significantly increase its capacity to resist lateral loading. To account for the reinforcement effect of cement-treated soil, a modified m approach is proposed by introducing a modified coefficient to enable the predictions of the lateral bearing capacity for such reinforced PC piles. It is revealed that the modified coefficient is approximately linearly related to the compressive bearing capacity of improved soil surrounds.

scholarly journals APPLICATION THE POINT FOUNDATION (PF) METHOD FOR SOFT SOIL IMPROVEMENT: A CASE STUDY FROM VETNAM

2020 ◽  
Vol 53 (2D) ◽  
pp. 1-18
Author(s):  
Bui Truong Son
Keyword(s):  
Bearing Capacity ◽  
Ground Improvement ◽  
Soft Soil ◽  
Soil Improvement ◽  
Static Compression ◽  
Successful Case ◽  
Soft Ground Improvement ◽  
Final Settlement ◽  
Shallow Footing

The point foundation method is the head enlarged cement deep mixing columns with high-quality control which can be used for soft ground improvement. The article aims to present the application of this method to treat soft soil for the foundation of Samse Vina factory, Ninh Binh province. The thickness of soft soil varies from 5.4 m to 7.4 m with high compressibility and low shear strength. Thus, point foundation was used to improve this layer. The prediction methods of soil bearing capacity and the settlement on the point foundation were calculated. After the treatment of soil, the unconfined compression strength of the point foundation column was determined and the static compression test for the point foundation column was also performed. The research results show that this method can significantly reduce the settlement of shallow footing and improved the bearing capacity of the soil. The final settlement of shallow footing was smaller than 2.54 cm and the bearing capacity of soil treatment can be satisfied with the requirement of construction building. This is a successful case of the application of point foundation to improve soft soil in Vietnam.

Toe-Bearing Capacity of Precast Concrete Piles through Biogrouting Improvement

2020 ◽  
Vol 146 (12) ◽  
pp. 06020026 ◽  
Author(s):  
Yang Xiao ◽  
Armin W. Stuedlein ◽  
Zhengyu Pan ◽  
Hanlong Liu ◽  
T. Matthew Evans ◽  
...  
Keyword(s):  
Bearing Capacity ◽  
Precast Concrete ◽  
Concrete Piles

Influence of Bending of Plastic Vertical Drain on Consolidation via Vacuum Preloading

2014 ◽  
Vol 644-650 ◽  
pp. 4826-4830
Author(s):  
Bin Bin Xu ◽  
Shotaro Yamada ◽  
Toshihiro Noda
Keyword(s):  
Ground Improvement ◽  
Ground Surface ◽  
Soft Ground ◽  
Finite Element Analyses ◽  
Vacuum Preloading ◽  
Vertical Drains ◽  
Bending Effect ◽  
Vertical Drain ◽  
Drainage Capacity ◽  
Soft Ground Improvement

The soft ground improvement employing vacuum preloading is widely used in Tianjin. In the application of vacuum preloading, the bending of plastic vertical drains (PVDs) often occurs accompanying the large settlement of the soft ground or the significant shear strain at the ground surface. In order to investigate the influence of bending of PVDs on the ground consolidation, three different bending shapes of PVDs are assumed and a series soil-water coupled finite element analyses are carried out. It is found that: 1) the macro-element method is available to take the bending effect of PVDs into consideration; 2) the bending at the bottom of PVDs has much impact on the consolidation of ground even though the hydraulic gradient at the bottom is much smaller than that at the top; 3) Due to the bending of PVDs at the bottom the drainage capacity is much influenced and the volumetric compression only occurs at the first few layers of the ground.

scholarly journals Forecasting bearing capacity performance with semi-empirical and theoretical methods applied to precast concrete piles founded on sandy clay in the region of Uberlândia-MG, Brazil

2020 ◽  
Vol 73 (4) ◽  
pp. 463-475 ◽  
Author(s):  
Armando Belato Pereira ◽  
Thiago Bomjardim Porto ◽  
Romero César Gomes ◽  
Raphael Lucio Reis dos Santos ◽  
João Marcos Guimarães Rabelo
Keyword(s):  
Bearing Capacity ◽  
Precast Concrete ◽  
Theoretical Methods ◽  
Concrete Piles ◽  
Sandy Clay ◽  
Semi Empirical ◽  
Capacity Performance

scholarly journals USING OF DYNAMIC AND STATIC LOAD PILING TESTS IN ASTANA, KAZAKHSTAN

2017 ◽  
Vol 2 (49) ◽  
pp. 32-37
Author(s):  
A. Z. Zhussupbekov ◽  
Z. A. Shakhmov ◽  
G. T. Tleulenova ◽  
S. B. Akhazhanov
Keyword(s):  
Bearing Capacity ◽  
Static Load ◽  
Precast Concrete ◽  
Load Test ◽  
Soil Conditions ◽  
Construction Sites ◽  
Concrete Piles ◽  
Test Methodology ◽  
Ground Conditions ◽  
Load Tests

In this paper the analysis results of precast piles different tests are presented. Extreme soil conditions of Astana (Kazakhstan) involve realizing the work precast piles in various soil ground and interaction soil ground and piles. There were carried out dynamic and static load tests of piles in extreme soil ground conditions in Astana. Based on data results of pile foundations the piles bearing capacity was determined. According to the results of DLT with PDA of driving piles (30.0 cm) the bearing capacity of the piles is 911 kN. The bearing capacity of the driven piles according to the results of SLT amounted to be 878 kN. Soils physic-mechanical properties in extreme conditions of Astana along with graphs of dependence are between settlement and load. The precise analysis of climatic and geological factors of the construction sites is shown. Investigations method for precast concrete piles testing is presented. Dynamic load test methodology in Astana for concrete piles testing is shown.  These investigations are important for of Pile-Soil interaction on problematical soil ground.

Research to build technological procedure for soft ground improvement using sea sand-cement-fly ash column

2020 ◽  
Vol 61 (HTCS6) ◽  
pp. 1-9
Author(s):  
Thinh Duc Ta ◽  
Phuc Dinh Hoang ◽  
Thang Anh Bui ◽  
Trang Huong Thi Ngo ◽  
Diu Thi Nguyen ◽  
...  
Keyword(s):  
Fly Ash ◽  
Load Capacity ◽  
Ground Improvement ◽  
Soft Soil ◽  
Soil Reinforcement ◽  
Soft Ground ◽  
Design Calculation ◽  
Sea Sand ◽  
Composite Ground ◽  
Soft Ground Improvement

Sea sand-cement-fly ash column technology for soft soil treatment is a new technology in the process of completing the theoretical basis, the experimental basis, and the construction of the ground treatment technological procedure. The paper presents the results of scientific research on design, calculation, construction, and acceptance of sea sand-cement-fly ash column. The scientific basis for the design of column is to consider the role of the column in composite ground, that is to use the column as soft ground improvement or soft soil reinforcement. The important parameters for the column design are: cement and fly ash content; column length; column diameter; number of columns; distance among columns; load capacity and settlement of composite ground. The sequence of steps of construction and acceptance of column includes: selection of construction equipment, preparation of construction sites, trial construction, official construction, evaluation of ground quality after treatment and preparation of document for acceptance.

Technical Basis for Application of Collapse Moments for Locally Thinned Pipes Subjected to Torsion and Bending Proposed for ASME Section XI

2014 ◽  
Author(s):  
Kunio Hasegawa ◽  
Yinsheng Li ◽  
Bostjan Bezensek ◽  
Phuong H. Hoang ◽  
Howard J. Rathbun
Keyword(s):  
Power Plants ◽  
Bending Moments ◽  
Finite Element Analyses ◽  
Pure Bending ◽  
Plastic Bending ◽  
Evaluation Procedures ◽  
Wall Thinning ◽  
Applicable Range ◽  
Technical Basis ◽  
Local Wall Thinning

Piping components in power plants may experience combined bending and torsion moments during operation. There is a lack of guidance for pipe evaluation for pipes with local wall thinning flaws under the combined bending and torsion moments. ASME B&PV Code Section XI Working Group is currently developing fully plastic bending pipe evaluation procedures for pressurized piping components containing local wall thinning subjected to combined torsion and bending moments. Using elastic fully plastic finite element analyses, plastic collapse bending moments under torsions were obtained for 4 (114.3) to 24 (609.6) inch (mm) diameter pipes with various local wall thinning flaw sizes. The objective of this paper is to introduce an equivalent moment, which combines torsion and bending moments by a vector summation, and to establish the applicable range of wall thinning lengths, angles and depths, where the equivalent moments are equal to pure bending moments.

Sign in / Sign up

Export Citation Format

Share Document