scholarly journals Internal Force Analysis of Buried-boring Piles in the Yuanzishan Landslide

2020 ◽  
Vol 10 (16) ◽  
pp. 5416 ◽  
Author(s):  
Hao Wang ◽  
Zhiying Lv ◽  
Jianwei Zhang ◽  
Jianwei Yue ◽  
Hongyu Qin ◽  
...  
Keyword(s):  
Driving Force ◽  
Limit Equilibrium ◽  
Bending Moment ◽  
Potential Method ◽  
Internal Force ◽  
Distribution Coefficients ◽  
Factors Affecting ◽  
Pile Diameter ◽  
Unstable Slope ◽  
Internal Forces

The Yuanzishan landslide is an unstable slope in Langzhong County, located in northeast Sichuan province, China. The Guangyuan-Nanchong expressway passes through the front edge of the unstable slope, and subgrade excavation has resulted in slope deformation, which threatens the safety of the highway construction. Emergency landslide control requires reduction of the slope disturbance. This study aims to investigate the use of buried-boring piles as a potential method for emergency landslide control. A simplified calculation method was used for the design of the buried-boring piles, according to the limit equilibrium of the soil and the elastic foundation coefficient method. The measured internal force changes of the pile were compared, in order to determine the distribution coefficients of the driving force. A relationship between the driving force of the shared pile ratio and the buried depth ratios was then established. Furthermore, a variety of factors affecting the internal forces of the buried-boring pile and the lateral reaction of the soil were also studied. The results revealed that (1) there was a quadratic relationship between the driving force of the pile-shared ratio and the sliding depth ratios; (2) the maximum bending moment of the pile increased with an increase in the sliding depth ratio of the pile, following a power law relationship; (3) increasing the buried depth of the pile head reduced the influence of the pile diameter on the maximum internal forces; (4) increasing the pile diameter decreased the maximum lateral reaction of the soil. The buried-boring piles can be used in similarly unstable regions for emergency control of deforming slopes.

Composite Lining Aseismic Design for Fault-Crossing Tunnel Structures

2014 ◽  
Vol 971-973 ◽  
pp. 30-34
Author(s):  
Chun Lei Xin ◽  
Bo Gao
Keyword(s):  
Active Faults ◽  
Three Dimensional ◽  
Bending Moment ◽  
Simulation Method ◽  
Internal Force ◽  
Great Earthquake ◽  
Underground Structures ◽  
Lining Structure ◽  
Internal Forces ◽  
Composite Lining

Although underground structures have stronger aseismic performance than ground structures, seismic disasters of mountain tunnels were fairly conspicuous in Wenchuan Great Earthquake. On the basis of seismic disaster analysis, a composite lining designfor tunnel structures across active fault was put forward. Three-dimensional numerical simulation method was used to analyze aseismic and damping effect of this structure. The results show that: (1)After setting aseismic and damping structure, the maximum internal forces value in lining the pattern of internal forces will not change. (2)Aseismic and damping structure setting can directly reduce the bending moment value and increase the axial force and stress force value in lining structure. (3) Relative to aseismic and damping structure, grouting region around damping layer can ameliorate internal force condition in lining structure and improve the effect of aseismic and damping structure. The above research results contribute to provide reference for seismic fortification of tunnel structures across active faults.

Seismic Behavior of Shear Wall-Frame Systems Considering Foundation Stiffness

2017 ◽  
Vol 17 (03) ◽  
pp. 1750041 ◽  
Author(s):  
Bo Di ◽  
Xueyi Fu
Keyword(s):  
Seismic Behavior ◽  
Safety Margin ◽  
Bending Moment ◽  
Shear Wall ◽  
Internal Force ◽  
Shallow Foundation ◽  
Frame Structure ◽  
Base Shear ◽  
Internal Forces ◽  
Frame Systems

In this paper, the influence of foundation stiffness on the seismic behavior of shear wall-frame systems was investigated. First, a basic differential equation was established to account for the interaction between the foundation and superstructure. By solving the equation, the influence of foundation stiffness on the lateral stiffness, inter-story drift, and internal force distribution of the superstructure at the elastic stage was elucidated. Subsequently, the concept and method for determining the range of foundation stiffness suitable for shear wall-frame systems were proposed. By taking a 12-story shear wall-frame structure built on a shallow foundation as an example, a parametric study was performed for various frame-to-wall relative stiffness ratios and foundation stiffnesses. The effect of shallow foundation stiffness on the base shear distribution and energy dissipation of the superstructure was clarified, with results compared with those of the fixed-base model. The analysis results indicated that the degeneration of foundation stiffness due to earthquake damages will result in significant redistribution of internal forces, namely, the internal forces of the walls decrease, while those of the frames increase. In particular, the shear-force and bending moment of the bottom frame columns rise drastically, which may greatly reduce the safety margin and should be considered in practical design.

Research on Internal Force Analysis of Shaking Table Test for Prestressed Pipe Piles Used in Tang Shan-Cao Feidian Expressway

2013 ◽  
Vol 740 ◽  
pp. 750-754
Author(s):  
Huan Sheng Mu ◽  
Ling Gao ◽  
Yu Guo Liang ◽  
Wen Dong Ma
Keyword(s):  
Axial Force ◽  
Shaking Table Test ◽  
Bending Moment ◽  
Internal Force ◽  
Sine Wave ◽  
Shaking Table ◽  
Pile Diameter ◽  
Pipe Model ◽  
Table Model ◽  
The Moment

In order to study the applicability of pipe piles in Tang-Cao expressway, shaking table model test was carried out. The results shows that, the internal force distribution of the pile under the action of seismic wave is basically the same with the behavior that is under the action of sine wave ; in the position of the 4 times pile diameter (distance the top of the pipe model about 200mm) appears the maximum axial force and bending moment; the change of the additional axial force in the upper portion of the pile is more complex, and tends to increase downward; the change of the moment tends to stable blow the distance of 20times the pile diameter from the pile top (distance the top of pipe model about 1000mm)

Research on Calculation Method of Internal Force Caused by Seasonal Temperature Difference in All-Vertical-Piled Wharf

2014 ◽  
Vol 1065-1069 ◽  
pp. 503-508
Author(s):  
Jun Jie Wang ◽  
Liang De He ◽  
Zhi Ming Zhang ◽  
Zhe Jiang Li
Keyword(s):  
Temperature Stress ◽  
Temperature Difference ◽  
Calculation Method ◽  
Internal Force ◽  
Calculation Model ◽  
Seasonal Temperature ◽  
Pile Diameter ◽  
Internal Forces ◽  
Foundation Pile ◽  
The One

When the wharf structure is completed, the temperature is different with the one at the usage period. The temperature difference will lead to the temperature strain, and create the lateral deformation and internal forces of the piles. Based on the assumption of the free temperature difference of beam-slab-system, the spatial simplified calculation model of the foundation pile and the stiff platform about the temperature stress in all-vertical-piled wharf is first proposed, the related calculation method is also given. The numerical example shows that the accuracy of this simplified method could meet the demand of preliminary design. In order to reduce the pile-top internal forces, the foundation piles should be arranged symmetrically. The pile-top internal forces are in direct proportion to the forth power of the pile diameter, with the increase of the pile diameter in all-vertical-piled wharf, the analysis of the temperature stress must be taken seriously.

Computing Method of Elastic Foundation Beam by MATLAB and its Application

2011 ◽  
Vol 368-373 ◽  
pp. 2760-2763
Author(s):  
Qiang Wang ◽  
Li Yuan Tong
Keyword(s):  
Elastic Foundation ◽  
Bending Moment ◽  
Internal Force ◽  
Beam Deflection ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Supporting Structure ◽  
Internal Forces ◽  
Computing Method ◽  
Elastic Foundation Beam

The elastic foundation beam method is the main method of stress analysis of the supporting structure of the foundation pit, it can easily calculate the internal forces and displacement of the structure, however, the computing method of elastic foundation beam deflection equation is more complicated. So according to the computation principle and method of elastic foundation beam, a computing program has been programmed by MATLAB mathematical software. The program has been applied to compute the internal force and deformation of deep foundation pit of Suzhou subway station. The variation law of displacement and bending moment of supporting structure during excavation has been obtained. The results of the measured and calculated agree well, and the computing results have efficiently guided and optimized supporting design.

scholarly journals Internal Force on and Deformation of Steel Assembled Supporting Structure of Foundation Pit under Thermal Stress

2021 ◽  
Vol 11 (5) ◽  
pp. 2225
Author(s):  
Fu Wang ◽  
Guijun Shi ◽  
Wenbo Zhai ◽  
Bin Li ◽  
Chao Zhang ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Bending Moment ◽  
High Strength ◽  
Element Model ◽  
Internal Force ◽  
Foundation Pit ◽  
Dimensional Finite Element ◽  
Influence Of Temperature On ◽  
Scale Experiment ◽  
Three Dimensional Finite Element

The steel assembled support structure of a foundation pit can be assembled easily with high strength and recycling value. Steel’s performance is significantly affected by the surrounding temperature due to its temperature sensitivity. Here, a full-scale experiment was conducted to study the influence of temperature on the internal force and deformation of supporting structures, and a three-dimensional finite element model was established for comparative analysis. The test results showed that under the temperature effect, the deformation of the central retaining pile was composed of rigid rotation and flexural deformation, while the adjacent pile of central retaining pile only experienced flexural deformation. The stress on the retaining pile crown changed little, while more stress accumulated at the bottom. Compared with the crown beam and waist beam 2, the stress on waist beam 1 was significantly affected by the temperature and increased by about 0.70 MPa/°C. Meanwhile, the stress of the rigid panel was greatly affected by the temperature, increasing 78% and 82% when the temperature increased by 15 °C on rigid panel 1 and rigid panel 2, respectively. The comparative simulation results indicated that the bending moment and shear strength of pile 1 were markedly affected by the temperature, but pile 2 and pile 3 were basically stable. Lastly, as the temperature varied, waist beam 2 had the largest change in the deflection, followed by waist beam 1; the crown beam experienced the smallest change in the deflection.

scholarly journals Business Sustainability of Start-Ups Based on Government Support: An Empirical Study of Korean Start-Ups

2019 ◽  
Vol 11 (18) ◽  
pp. 4851 ◽  
Author(s):  
Wooseung Lee ◽  
Boyoung Kim
Keyword(s):  
Market Orientation ◽  
Driving Force ◽  
Government Support ◽  
Flow Experience ◽  
Factors Affecting ◽  
Business Sustainability ◽  
Emerging Nations ◽  
The Government ◽  
Start Ups ◽  
New Jobs

Since the mid-2000s, start-ups have increasingly become the driving force of new jobs and growth engines for advanced countries, and emerging nations are striving to vitalize start-ups through active government support policies. However, approximately 30% of start-ups shut down within two years of their foundation. Accordingly, this study determines the factors affecting the business sustainability of start-ups as based on available government support and provides suggestions to increase the effectiveness of the government-supported projects. This study conducted a survey of 273 start-ups in Korea, and empirically analyzed whether factors such as entrepreneurship, market orientation, and network affected business sustainability by using flow experience and entrepreneurial satisfaction as mediators. The results found that entrepreneurship affected business sustainability with flow experience and entrepreneurial satisfaction as the mediators, while market orientation affected business sustainability using flow experience as the mediator, and network affected business sustainability with entrepreneurial satisfaction as the mediator.

DISLOCATION OF FACE-SLABS OF ZIPINGPU CONCRETE FACE ROCKFILL DAM DURING WENCHUAN EARTHQUAKE

2012 ◽  
Vol 06 (02) ◽  
pp. 1250007 ◽  
Author(s):  
DEGAO ZOU ◽  
YANG ZHOU ◽  
HOE I. LING ◽  
XIANJING KONG ◽  
BIN XU
Keyword(s):  
Wenchuan Earthquake ◽  
Limit Equilibrium ◽  
Failure Surface ◽  
Ground Acceleration ◽  
Factors Affecting ◽  
2008 Wenchuan Earthquake ◽  
Rockfill Dam ◽  
Concrete Face ◽  
Concrete Face Rockfill Dam ◽  
Water Elevation

Zipingpu concrete face rockfill dam (CFRD) is one of the tallest dams that have ever been subjected to strong earthquake shaking and recorded damages. In this paper, finite element method and limit equilibrium method are used to determine the most critical failure surface for Zipingpu CFRD during the 2008 Wenchuan earthquake in China. The dislocation damage of the face-slab joint was then obtained from the sliding block analysis. The major factors affecting dislocation displacement of face-slabs were analyzed. The results showed that the rigid sliding block method is relevant for analyzing the damage of face-slabs of CFRD during earthquake. The peak ground acceleration had a significant influence on the dislocation. As the acceleration of the dam increases with the height while the strength of face-slab joints reduces, the dislocation could easily occur when the upstream slope of the dam started to slide. The water elevation had considerable impact on the dislocation of face-slabs during strong shaking. There might be no dislocation of face-slabs at full reservoir, and the water elevation just above construction joints would induce larger damage.

Structural Analysis and Internal Force Calculation of Variable Cross-Section Silo

2012 ◽  
Vol 446-449 ◽  
pp. 429-434
Author(s):  
Rui Ting Ma
Keyword(s):  
Cross Section ◽  
Variable Cross Section ◽  
Internal Force ◽  
Variable Cross ◽  
Axially Symmetric ◽  
Internal Forces ◽  
Differential Element ◽  
Symmetric Load ◽  
Force Calculation ◽  
Constant Section

In this paper, the differential element of constant-section silo wall suffering from axially symmetric load is analyzed. From the results of constant-section silo, the author derives the displacements and internal forces of variable cross-section silo. Through a specific example, this paper compares the displacements , internal forces and concrete consumption of variable cross-section silo with those of constant-section silo, and discusses the merits of variable cross-section silo.

scholarly journals Improvement of trawler hull structure under condition of ensuring fatigue strength

2021 ◽  
Vol 4 (7(112)) ◽  
pp. 50-59
Author(s):  
Leontii Korostylov ◽  
Dmytro Lytvynenko ◽  
Hryhorii Sharun ◽  
Ihor Davydov
Keyword(s):  
Fatigue Strength ◽  
Fatigue Damage ◽  
Hot Spot ◽  
Fatigue Cracks ◽  
Bending Moment ◽  
Theoretical Method ◽  
Corrosive Wear ◽  
Hot Spot Stress ◽  
Hull Structure ◽  
Internal Forces

The structure of the hull of the project 1288 trawler in a region of fore hold was improved to ensure fatigue strength of assemblies of the intersection of main frames with the second bottom. To this end, a study of the fatigue strength of these assemblies was carried out for the original side structure and two versions of its modernization. Values of internal forces at the points of appearance of fatigue cracks in the compartment have been determined for three design versions of the side. It was found that the greatest forces act in the middle of the fore half of the compartment. Calculations of parameters of the long-term distribution of magnitudes of ranges of total equivalent operating stresses according to the Weibull law in the points of occurrence of fatigue cracks for different design versions of the side grillage have been performed. These parameters were determined for the middle of the fore hold of the vessel and for the areas in which maximum values of bending moment ranges are in effect with and without corrosive wear. Values of total fatigue damage and durability of the studied assemblies were determined. Calculations were carried out by nominal stress method, hot spot stress method, and experimental and theoretical method. It was shown that in order to ensure fatigue strength of the assembly under consideration, it is necessary to extend the intermediate frames of the original version of the side structure to the level of the second bottom fixing them to the deck. It is also necessary to attach a cargo platform to the side thus reducing the frame span. As a result, the level of fatigue damage over 25 years of operation will decrease by about 3.5 times. As it was found, approximate consideration of the slamming effect does not significantly increase the amount of fatigue damage to the assembly. The results of the development of recommendations for modernization of the side structure can be implemented both on ships of the 1288 project and on other ships with a transverse side framing system.

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