Cable Deflection and Gravity Stiffness of Cable-Stayed Suspension Bridge

2011 ◽  
Vol 255-260 ◽  
pp. 1039-1042 ◽  
Author(s):  
Guo Ping Xia ◽  
Zhe Zhang

The paper studye the cable deflections of cable-stayed suspension bridge subject to living load. in addition, an analytical formula of the gravity stiffness of the cable-stayed suspension bridge is derived. Duo to the dead load state in the cable-stayed part is more differ from that in the suspension part, the research aim at different parts of the cable in the cable-stayed suspension bridge. Using the energy relation principle associated with deformation of the cable, the cable deflections and gravity stiffness of cable-stayed suspension bridge are derived.

2011 ◽  
Vol 368-373 ◽  
pp. 2175-2179
Author(s):  
Tian Lai Yu ◽  
Hong Kun Han ◽  
Xin Yu Li ◽  
Qiang Ma

The shear resistant with SWR (steel wire rope) external prestressing is a kind of new type of reinforcement technique. The advantages of the method are ideal reinforcement effect, durability, and convenient construction. So the method has been paid attention by more and more scientists and technical workers. Through the experiment of 1 basic beam and 3 strengthened beams which are in different dead load levels, the influence of damage degree of original beams and the dead load level of strengthened beams are analyzed. The reduction coefficient values of shear capacity under different dead load level are researched. The research is shown that: with the dead load level increasing, the improve degree of shear capacity of strengthened concrete beams is smaller. The mathematical model is established, which is about dead load level and reduction coefficient of shear capacity of strengthened concrete beams. The result is to take 0.75 as the reduction coefficient of shear capacity. The value is reasonable in calculating the shear bearing capacity of strengthened beams under dead load.


Author(s):  
Guntur Nugroho ◽  

Health monitoring using vibration technique is usually conducted on cable structure. The hanger cable on the suspension bridge has a difference of span. To predict axial force of cable, the beam-string theory includes a parameter of bending stiffness. However, string theory has neglected the effect of bending stiffness. The shorter the span of the cable the greater the effect of the bending stiffness would be. This paper raises parameter moment of inertia to span ratio (I/L) to determine the apropriate analytical formula between string and beam-string. Experimental research was conducted using a vibration technique. The specimens use solid cylindrical steel beam, having length specimens of 2 m, hinge-hinge of boundary condition, and difference variations I/L of 0.024, 0.08, 0.58, 1.53 and 10.22. Numerical analysis was simulated by using Abaqus software v 6.13. The result shows that the ratio of I/L equally lowers than 0.082 has close to the analytical string theory. The ratio of I/L greather than 0.082 has close to the beam string theory.


2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Xingwei Xue ◽  
Meizhong Wu ◽  
Zhengwei Li ◽  
Peng Zhou

Moment and shear load distribution are important in bridge design. Most existing studies have focused on the distribution of girders under vehicle loading, neglecting the dead load distribution between the webs of multicell box-girders. Through the “Sum of Local Internal Forces” function, the shear force of each web in the multicell box-girder 3D finite element model was extracted and analysed using the dead load shear force distribution factor. The research parameters include the slope of the web, support condition, and cell number with respect to the dead load shear force distribution factor. The results indicate that the dead load shear distribution in the webs of multicell box-girders is uneven. The outermost inclined web bears a shear force greater than the average shear force, which must be considered in bridge design.


1956 ◽  
Vol 29 (3) ◽  
pp. 852-856
Author(s):  
R. F. Blackwell

Abstract Hardness determinations are frequently required on very soft rubbers in the range of 5 to 30 (Shore). It is usual to make such measurements in the shop with a pocket-type tester; however this is not entirely satisfactory for laboratory work where a more precise reading is usually required, calling for a hardness tester of the dead-load type. Such a tester, moreover, is useful to keep a check on the accuracy of pocket testers. The British Standard dead-load hardness tester is not calibrated below 30° BS, but a method of extending the range downwards has been proposed, whereby the standard indentor of this tester is replaced by one of 0.25 inch diam.; unfortunately this method has the disadvantage of involving more than one revolution of the dial gauge needle, and a directly calibrated scale would be out of the question. There is, however, an alternative method in use at BRPRA, which gives hardness readings down to 4° in one revolution; and which replaces the standard added load of 535 grams by one of 70 grams. At present, a calibration curve is provided to convert from scale reading to hardness degrees, but it is intended to add a second scale in due course.


2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Yan-Qi Yin ◽  
Bo Zhang ◽  
Yue-ming Li ◽  
Wei-Zhen Lu

The dynamic characteristics of a rotating cantilever Timoshenko beam under dead load are investigated in this paper. Considering the predeformation caused by dead load and centrifugal force, governing equation of rotating cantilever Timoshenko beam is derived based on Hamilton’s principle, and the influence of the load on natural vibration is revealed. A suit of modal experimental apparatus for cantilever beam is designed and used to test the natural frequencies under the dead load, and the natural frequencies under rotation condition are calculated with a commercial finite element code. Both the experimental result and numerical result are utilized to compare with the present theoretical result, and the results obtained by present modeling method show a good agreement with those obtained from the experiment and finite element method. It is found that the natural frequencies of cantilever beam increase with both the dead load and the rotating speed.


2021 ◽  
Vol 4 (3) ◽  
pp. 615
Author(s):  
Orlando Orlando ◽  
Gregorius Sandjaja Sentosa

Foundation is the lower structure of the building located below the ground that has the function to bear the load of the building. The building has been standing for ± 5 years and the slope of the building is ± 1-20. The authors analyzed soil bearing capacity, settlement and the slope of the building and the possibility of repairing the building for reuse. In 1 pile cap there are 4 bore piles with a depth of 6m-12m, because the pile cap data is not obtained then the size and thickness is assumed and the soil data used is secondary data without lab data derived from soil data in locations adjacent to the building site that is ±100m from the building site. After the analysis, soil bearing capacity is not strong to bear the dead load of the building when using a foundation with a depth of 6m-12m, there is a possibility that the foundation used is not suitable and there is a reduction in the load of the building due to the presence of other buildings that are adjacent to the building in the analysis resulting in a considerable decrease and slope of the building.Fondasi adalah struktur bagian bawah bangunan yang terletak di bawah permukaan tanah yang mempunyai fungsi memikul beban bangunan. Bangunan ini sudah berdiri selama ± 5 tahun dan  kemiringan bangunan sebesar ± 1-20. Penulis menganalisis daya dukung tanah, penurunan tanah dan kemiringan bangunan dan kemungkinan memperbaiki bangunan agar dapat digunakan kembali. Pada 1 pile cap terdapat 4 buah bore pile dengan kedalaman 6m–12m, karena data pile cap  tidak diperoleh maka ukuran dan ketebalannya diasumsikan dan data tanah yang digunakan adalah data sekunder tanpa data lab yang berasal dari data tanah di lokasi berdekatan dengan lokasi bangunan yang berjarak ±100m dari lokasi bangunan. Setelah di analisis, daya dukung tanah tidak kuat untuk menahan beban mati bangunan bila menggunakan fondasi dengan kedalaman 6m–12m dan ada kemungkinan fondasi yang digunakan tidak sesuai dan terjadi reduksi beban bangunan karena adanya bangunan lain yang berdempetan dengan bangunan yang di analisis sehingga mengakibatkan penurunan dan kemiringan bangunan yang cukup besar.


2014 ◽  
Vol 587-589 ◽  
pp. 1650-1654
Author(s):  
Mu Xin Luo ◽  
Jing Hong Gao

In the condition of the same span, to change the continuous curved bridge's curvature radius and under the dead load and moving load to compare how the internal force changes in different curvature radius. The finite element model is established to simulate the actual structure by Midas Civil. Results in a continuous curved bridge which main span of less than 60m, under the dead load, bending moment (-y) is unlikely to change, reinforced by a straight bridge can meet the requirements; under the moving loads, the curvature radius of the bending moment (-y) has little influence, should focus on increase in torque and bending moment (-z).


2007 ◽  
Vol 21 (07) ◽  
pp. 1051-1058
Author(s):  
T. R. HAMMAD

This work presents the results of the resistivity vs. temperature measurements obtained under different excitation currents, carried out on Nd 1.783 Ce 0.15 CuO 3.989 followed by the new analytical formula Nd 2-(4x + v-2)/3 Ce 0.15 CuO y. The measurements revealed different characteristics for different parts of the investigated sample. The obtained results may suggest the idea that double resistive superconducting transition in n-type polycrystalline cuprates is of a rather extrinsic future. The electron microscope photography applied in order to investigate the microstructure of the chosen samples also supported the above view.


1808 ◽  
Vol 98 ◽  
pp. 164-186 ◽  

Having lately fixed on the discussion of the nature of in­flammation, for the subject of an academical exercise, I found it necessary to examine attentively the mechanical principles of the circulation of the blood, and to investigate minutely and comprehensively the motion of fluids in pipes, as affected by friction, the resistance occasioned by flexure, the laws of the propagation of an impulse through the fluid contained in an elastic tube, the magnitude of a pulsation in different parts of a conical vessel, and the effect of a contraction advancing progressively through the length of a given canal. The phy­siological application of the results of these inquiries I shall have the honour of laying before the Royal Society at a future time; but I have thought it advisable to communicate, in a separate paper, such conclusions, as may be interesting to some persons, who do not concern themselves with disquisitions of a physiological nature; and I imagine it may be as agreeable to the Society that they should be submitted at pre­sent to their consideration, as that they should be withheld until the time appointed for the delivery of the Croonian Lecture. It has been observed by the late Professor Robison, that the comparison of the Chevalier Dubuat's calculations with his experiments is in all respects extremely satisfactory; that it exhibits a beautiful specimen of the means of expressing the general result of an extensive series of observations in an analytical formula, and that it does honour to the penetra­tion, skill, and address of Mr. Dubuat, and of Mr. de St. Honore', who assisted him in the construction of his expres­sions: I am by no means disposed to dissent from this enco­mium; and I agree with Professor Robison, and with all other late authors on hydraulics, in applauding the unusually accurate coincidence between these theorems and the experi­ments from which they were deduced.


2021 ◽  
Vol 272 ◽  
pp. 01019
Author(s):  
Guojun Yang ◽  
Qiwei Tian ◽  
Guangwu Tang ◽  
Longlong Li ◽  
Su Ye ◽  
...  

The dynamic characteristics of long-span suspension bridges are complex. The natural vibration frequency is changed with different structural parameters, and the sensitivity to different parameters is different. In order to solve this problem, the spatial model of a long-span suspension bridge was established by using finite element software, and the first 20 natural vibration periods, natural vibration frequencies and vibration modes were analyzed and calculated. The accuracy of the obtained natural vibration frequency data was verified through field tests. Finally, based on the model, the stiffness of structural components is studied by one -factor-at-one-time, and the influence of various variables on the frequency and mode of a certain mode is studied by one-factor-at-one-time method. The results show that different structural parameters have different effects on the vibration frequency. When the stiffness of stiffening girder and main tower is changed, with the increase of stiffness, the variation of frequency mostly presents an upward trend, and the range is large. With the change of the secondary dead load, most of the frequencies decrease first and then tend to be stable. It can be seen from the field test results that the vibration shapes and frequencies measured by numerical simulation and test are close to each other, which can meet the requirements of engineering precision. The stiffness of the main cable and the main tower has a great influence on the modes and periods corresponding to them. The increase of the secondary dead load can reduce the natural vibration frequency of the suspension bridge, but it is not unlimited to increase the secondary dead load to reduce the frequency. The stiffness of the stiffening girder has a great influence on the frequency of the suspension bridge. When the bending stiffness of the stiffening girder increases to 3 times of the original one, the order of vibration modes of the structure will change. The research results can provide references for structural design and dynamic parameter adjustment of long-span suspension bridge.


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