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

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)

Author(s):  
Dingwen Zhang ◽  
Anhui Wang ◽  
Xuanming Ding

A series of shaking table model tests were performed to examine the effects of deep cement mixing (DCM) columns with different reinforcement depths on the seismic behavior of a pile group in liquefiable sand. Due to the DCM column reinforcement, the fundamental natural frequency of the model ground increases noticeably. The excess pore pressure of soils reduces with the increase of reinforcement depths of the DCM columns. Before liquefaction, the acceleration response of soils in the improved cases is obviously lower than that in the unimproved case, but the acceleration attenuation is greater after liquefaction in the unimproved case. Moreover, the lateral displacement of the superstructure, the settlement of the raft, and the bending moment of the piles in the improved cases are significantly reduced compared to those in the unimproved case, and the reduction ratios rise with the increase of reinforcement depth of the DCM columns. However, reinforcement by the DCM columns may result in the variation of the location of the maximum moment that occurs in the pile.


2020 ◽  
Vol 10 (16) ◽  
pp. 5416 ◽  
Author(s):  
Hao Wang ◽  
Zhiying Lv ◽  
Jianwei Zhang ◽  
Jianwei Yue ◽  
Hongyu Qin ◽  
...  

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.


2019 ◽  
Vol 2019 ◽  
pp. 1-17 ◽  
Author(s):  
Shujin Li ◽  
Cai Wu ◽  
Fan Kong

A building developed by Wuhan Shimao Group in Wuhan, China, is a high-rise residence with 56 stories near the Yangtze River. The building is a reinforced concrete structure, featuring with a nonregular T-type plane and a height 179.6 m, which is out of the restrictions specified by the China Technical Specification for Concrete Structures of Tall Building (JGJ3-2010). To investigate its seismic performance, a shaking table test with a 1/30 scale model is carried out in Structural Laboratory in Wuhan University of Technology. The dynamic characteristics and the responses of the model subject to different seismic intensities are investigated via the analyzing of shaking table test data and the observed cracking pattern of the scaled model. Finite element analysis of the shaking table model is also established, and the results are coincident well with the test. An autoregressive method is also presented to identify the damage of the structure after suffering from different waves, and the results coincide well with the test and numerical simulation. The shaking table model test, numerical analysis, and damage identification prove that this building is well designed and can be safely put into use. Suggestions and measures to improve the seismic performance of structures are also presented.


2015 ◽  
Vol 744-746 ◽  
pp. 1033-1036
Author(s):  
Zi Chang Shangguan ◽  
Shou Ju Li ◽  
Li Juan Cao ◽  
Hao Li

In order to simulate moment distribution on linings of tunnel excavated by shield, FEM-based procedure is proposed. According to geological data of tunnel excavated by shield, FEM model is performed, and the moment, axial force and shear force distributions on linings are computed. The maximum moment on segments decreases while Poisson’s ratio of soil materials touching to segments increases. The moment value and distribution vary with Young’s modulus of soil materials. The maximum positive moment on linings is approximately equal to the maximum negative moment.


2013 ◽  
Vol 838-841 ◽  
pp. 397-401
Author(s):  
Ming Li ◽  
Ren Wang Liang

In this paper, taking one deep excavation engineering as an example, modeling by the FLAC3D finite difference software, combining with the Lizheng deep excavation supporting design software, taking the equivalent stiffness of combination pile as 2.300-4.789(10-2m3), and analyzing the pile body bending moment, anchor axial force and pit deformation by considering interaction of pile stiffness. In addition, in this paper the influence factors of pile stiffness has been discussed, and provides a reference for the engineering design.


2019 ◽  
Vol 5 (7) ◽  
pp. 1440-1451
Author(s):  
Ernesto Fenollosa ◽  
Iván Cabrera ◽  
Verónica Llopis ◽  
Adolfo Alonso

This article shows the influence of axial force eccentricity on high strength concrete columns design. The behavior of columns made of normal, middle and high strength concrete with slenderness values between 20 and 60 under an eccentric axial force has been studied. Structural analysis has been developed by means of software which considers both geometrical and mechanical non-linearity. The sequence of points defined by increasing values of axial force and bending moment produced by eccentricity has been represented on the cross-section interaction diagram until failure for each tested column. Then, diagrams depicting the relationship between failure axial force and column's slenderness have been drawn. The loss of bearing capacity of the member for normal and middle strength columns when compared with the bearing capacity of their cross-section is more noticeable as axial force eccentricity assumes higher values. However, this situation reverses for high strength columns with high slenderness values. On the basis of results obtained, the accuracy level for the moment magnifier method was checked. Despite the good concordance in most of the cases, it was verified that the moment magnifier method leads to excessively tight results for high strength concrete columns with high slenderness values. In these specific cases, a coefficient which amends the column rigidity is proposed so as to obtain safer values.


2021 ◽  
Vol 631 (1) ◽  
pp. 012053
Author(s):  
Fulin Shen ◽  
Xiaochun Song

Abstract This paper theoretical analysis the internal force of the fixed parabolic arches under radient temperature gradient field incorporating shear deformations. The effective centroid of the arch-section under linear temperature gradient is derived. Based on force method and energy method, the analytical solutions of the internal force of fixed parabolic arches at pre-buckling under linear temperature gradient field are derived. A parameter study was carried out to study the influence of linear temperature gradient on the internal force of the fixed parabolic arches with different rise-span ratio and varying slenderness ratio. It is found that the temperature gradient and the rise-span ratio has a significant influence on the internal force of the parabolic arches, the influence of shear deformation causes the bending moment increase while the axial force decreases, and the axial force of parabolic arches decreases as the rise-span ratio increases.


2011 ◽  
Vol 255-260 ◽  
pp. 4237-4241 ◽  
Author(s):  
Jian Ping Han ◽  
Jiong Qian ◽  
Pei Juan Zheng

Damage occurs in components and joints while the structure is affected by strong ground motions. Dynamic characteristics of the structure will change with the deterioration of strength and stiffness. Analyzing and processing the vibration signals is one of the mainstream ways for structural health monitoring and damage identification. In this paper, Hilbert-Huang transform is adopted to identify structural damage. Time-varying instantaneous frequency and instantaneous energy is used to identify the damage evolution of the structure. And relative amplitude of Hilbert marginal spectrum is used to identify the damage location of the structure. Finally, the acceleration records at gauge points from the shaking table test of a 12-storey reinforced concrete frame model are processed. Evolution and location of the model damage are identified. Identification results agree well with experimental observation. This indicates that the proposed approach is capable to identify damage of the structure.


2011 ◽  
Vol 147 ◽  
pp. 140-144
Author(s):  
Jia Zhu Xue ◽  
Yv Zhang Chi ◽  
Xiang Cao Zhi

The alien space meridians stair steel structure is first adopted in Taizhou medical city exhibition center project. Based on the finite element calculation method for curved beam element stiffness matrix, convergence standard controls and iteration method of solving the modification and optimization in this paper, the complex alien space meridians framed calculation model is built, and the distribution of axial force and bending moment distribution of the stairs meridians skeleton structure are calculated, and the position and numbers are determined. Numerical results show that the maximum space alien meridians stair axial force is 34.5 KN and maximum bending moment is 5.9 KN•m, which satisfy the standard requirement, then the size curvature big, mechanical transmission line complex and local internal force big technology problem skeleton structure have been solved .Therefore, a strong engineering application value achieves in this paper.


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