Suspension bridge deformation and internal forces under the concentrated live load: Analytical algorithm

The girder of self-anchored suspension bridge is subjected to large compression force applied by main cables. So, serious damage of the girder due to breakage of hangers may cause the collapse of the whole bridge. With the time increasing, the hangers may break suddenly for their resistance capacities decrease due to corrosion. Using nonlinear static and dynamic analysis methods and adopting 3D finite element model, the responses of an actual self-anchored suspension bridge to sudden breakage of hangers are studied in this paper. The results show that the sudden breakage of a hanger causes violent vibration and large changes in internal forces of the bridge. In the process of the vibration, the maximum tension of hanger produced by breakage of a hanger exceeds 2.22 times its initial value, and the reaction forces of the bearings increase by more than 1.86 times the tension of the broken hanger. Based on the actual bridge, the influences of some factors including flexural stiffness of girder, torsion stiffness of girder, flexural stiffness of main cable, weight of girder, weight of main cable, span to sag ratio of main cable, distance of hangers, span length, and breakage time of hanger on the dynamic responses are studied in detail, and the influencing extent of the factors is presented.

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KINERJA BANGUNAN BERTINGKAT DI KAWASAN PESISIR DALAM MENUNJANG KEMARITIMAN DAN PARIWISATA DI BANYUWANGI

Construction and Material Journal ◽

10.32722/cmj.v2i2.3094 ◽

2020 ◽

Vol 2 (2) ◽

pp. 131-141

Author(s):

M. Shofi'ul Amin ◽

Mirza Ghulam ◽

Dadang Dwi P ◽

Erwin E

Keyword(s):

Threshold Value ◽

Lateral Load ◽

Computer Applications ◽

Wind Loads ◽

Live Load ◽

Lateral Loads ◽

Earthquake Load ◽

Survey Results ◽

Internal Forces ◽

Response Method

AbstractBanyuwangi is an area that belongs to zone 4 (SNI 03-1726-2002) and areas that are prone to earthquakes and are classified as moderate (SNI 03-1726-2012 and 2019). Other than, Banyuwangi also has the longest coastline on the island of Java, so buildings located in coastal areas have different air pressure that can cause very large winds to blow. So that in planning a building not only dead load and live load that needs to be planned but lateral loads also need to be planned. The survey results contained a tourism support building structure and are located very close to the coastal area of the Banyuwangi Dialoog Hotel. So the focus of this research is the construction of the structure. As for what is analyzed is the value of internal forces and deviations to the lateral loads of earthquake SNI 03-1726-2019 and wind loads based on PPIUG 1983 using the help of structural computer applications. The method used in earthquake load analysis is the spectrum response method. The results of the analysis of the value of the maximum force due to earthquake loads and wind loads are most influential on the column elements that cause inter-floor deviation. The deviation value is reviewed in the building service boundary performance, namely in the x and y directions respectively 10.89 mm and 15.75 mm. When viewed from the service threshold value of 87.5 mm, the structure is classified as safe from the influence of the lateral load of the planned earthquake and wind load. So that the building is feasible as a coastal building that is quite safe for commercial buildings and is able to become a tourist destination because it is so close to the sea. Keywords: Coastal, lateral load, drift, tourismAbstrakBanyuwangi merupakan daerah yang termasuk wilayah zona 4 (SNI 03-1726-2002) dan daerah yang rawan terjadi gempa serta tergolong tingkat sedang (SNI 03-1726-2012 dan 2019). Selain itu, Banyuwangi juga memiliki garis pantai terpanjang di pulau Jawa, sehingga bangunan yang terletak di kawasan pesisir memiliki perbedaan tekanan udara yang bisa menyebabkan angin bertiup sangat besar. Sehingga dalam perencanaan suatu bangunan tidak hanya beban mati dan beban hidup saja yang perlu direncanakan melainkan beban lateral juga perlu direncanakan. Hasil survei terdapat struktur gedung penunjang pariwisata dan terletak sangat dekat sekali dengan kawasan pesisir yaitu Hotel Dialoog Banyuwangi. Maka fokus pada penelitian ini yaitu konstruksi pada struktur tersebut. Adapun yang dianalisis adalah nilai gaya dalam dan simpangan terhadap beban lateral gempa SNI 03-1726-2019 dan beban angin berdasarkan PPIUG 1983 dengan menggunakan bantuan aplikasi komputer struktur. Metode yang digunakan dalam analisis beban gempa adalah metode respon spektrum. Hasil analisa nilai gaya dalam maksimum akibat beban gempa dan beban angin yang paling berpengaruh yaitu pada elemen kolom yang mengakibatkan terjadinya simpangan antar lantai. Nilai simpangan tersebut ditinjau pada kinerja batas layan bangunan tersebut yaitu pada arah x dan y masing-masing adalah 10,89 mm dan 15,75 mm. Jika ditinjau dari nilai ambang batas layan yaitu 87,5 mm, maka struktur tersebut tergolong aman dari pengaruh beban lateral gempa rencana dan beban angin. Sehingga bangunan tersebut layak sebagai bangunan pesisir yang cukup aman untuk bangunan komersil serta mampu menjadi destinasi wisata karena letaknya yang sangat dekat dengan laut. Kata kunci: Pesisir, beban lateral, simpangan, pariwisata

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Effects of the highway live load on the additional forces of the continuously welded rails of a long-span suspension bridge

Proceedings of the Institution of Mechanical Engineers Part F Journal of Rail and Rapid Transit ◽

10.1177/09544097211061921 ◽

2021 ◽

pp. 095440972110619

Author(s):

Xiangdong Yu ◽

Nengyu Cheng ◽

Haiquan Jing

Keyword(s):

High Speed ◽

Suspension Bridge ◽

Additional Stress ◽

Live Load ◽

Analysis Model ◽

Maximum Displacement ◽

Obvious Effect ◽

Long Span Bridges ◽

Long Span ◽

Track Bridge

High-speed running trains have higher regularity requirements for rail tracks. The track-bridge interaction of long-span bridges for high-speed railways has become a key factor for engineers and researchers in the last decade. However, studies on the track-bridge interaction of long-span bridges are rare because the bridges constructed for high-speed railways are mainly short- or moderate-span bridges, and the effects of the highway live load on the additional forces of continuously welded rails (CWRs) have not been reported. In the present study, the effects of the highway live load on the additional forces of a CWR of a long-span suspension bridge are investigated through numerical simulations. A track-bridge spatial analysis model was established using the principle of the double-layer spring model and the bilinear resistance model. The additional stress and displacement of the rail are calculated, and the effects of the highway live load are analyzed and compared with those without a highway live load. The results show that the highway live load has an obvious effect on the additional forces of a CWR. Under a temperature force, the highway live load increases the maximum tensile stress and compressive stress by 10 and 13%, respectively. Under a bending force, the highway live load increases the maximum compressive rail stress and maximum displacement by 50 and 54%, respectively. Under a rail breaking force, when the highway live load is taken into consideration, the rail displacement at both sides of the broken rail varies by 50 and 42%, respectively. The highway live load must be taken into consideration when calculating the additional forces of rails on highway-railway long-span bridges.

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Performance-Based Design Research on a Long-Span High-Speed Railway Suspension Bridge

IABSE Congress, New York, New York 2019: The Evolving Metropolis ◽

10.2749/newyork.2019.1726 ◽

2019 ◽

Author(s):

Xiaoguang Liu ◽

Hui Guo ◽

Xinxin Zhao ◽

Pengfei Su ◽

Mangmang Gao

Keyword(s):

High Speed ◽

Rotation Angle ◽

Suspension Bridge ◽

Performance Based Design ◽

Live Load ◽

Stay Cable ◽

Expansion Joint ◽

High Speed Railway ◽

Track Geometry ◽

Study Results

<p>A performance-based design (PBD) framework for high-speed railway suspension bridge is proposed from aspects of structural, operational and public requirements. Stiffness indexes are discussed. Results show that target performance shall include stiffness, strength, fatigue, stability, track geometry, train operation performance, human safety and public loss, etc. Case study results of a high-speed railway suspension bridge show that large cable force provide gravity stiffness with the vertical deflection to main span length is 1/488 under static live load. The longitudinal displacement (LD) is restricted to a proper value by arrangement of inclined stay cable at the mid-span and the viscous dampers between pylon and stiffening girder. LD at girder end under the total live load is 261mm. And the longitudinal drift mode shape appears later than symmetrical transverse and vertical bending. The vertical rotation angle at girder end is only 0.77‰ under ZK load (0.8UIC) for passenger-dedicated line by setting auxiliary pier at side span of the bridge. Considering the operational performance, elastic deformation of wind-resistant bearings at girder end shall be restricted to decrease the transverse rotation angle which has the limit value from 1.0‰ to 2.5‰ under different train speed. And the integral design of bridge expansion joint (BEJ) and rail expansion joint (REJ) at girder end is required.</p>

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Geometric Nonlinear Analysis of Self-Anchored Cable-Stayed Suspension Bridges

The Scientific World JOURNAL ◽

10.1155/2013/734387 ◽

2013 ◽

Vol 2013 ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

Wang Hui-Li ◽

Tan Yan-Bin ◽

Qin Si-Feng ◽

Zhang Zhe

Keyword(s):

Geometric Nonlinearity ◽

Suspension Bridge ◽

Order Theory ◽

Second Order ◽

Suspension Bridges ◽

Live Load ◽

Main Cable ◽

Axial Forces ◽

Shrinkage And Creep ◽

Geometric Nonlinear Analysis

Geometric nonlinearity of self-anchored cable-stayed suspension bridges is studied in this paper. The repercussion of shrinkage and creep of concrete, rise-to-span ratio, and girder camber on the system is discussed. A self-anchored cable-stayed suspension bridge with a main span of 800 m is analyzed with linear theory, second-order theory, and nonlinear theory, respectively. In the condition of various rise-to-span ratios and girder cambers, the moments and displacements of both the girder and the pylon under live load are acquired. Based on the results it is derived that the second-order theory can be adopted to analyze a self-anchored cable-stayed suspension bridge with a main span of 800 m, and the error is less than 6%. The shrinkage and creep of concrete impose a conspicuous impact on the structure. And it outmatches suspension bridges for system stiffness. As the rise-to-span ratio increases, the axial forces of the main cable and the girder decline. The system stiffness rises with the girder camber being employed.

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An analytical algorithm for the pylon saddle pushing stage and distance during the suspension bridge construction

Advances in Structural Engineering ◽

10.1177/1369433219862436 ◽

2019 ◽

Vol 22 (15) ◽

pp. 3290-3305

Author(s):

Wen-ming Zhang ◽

Kai-rui Qian ◽

Gen-min Tian ◽

Zhao Liu

Keyword(s):

Stress State ◽

Proper Time ◽

Bending Moment ◽

Strength Criterion ◽

Suspension Bridge ◽

Suspension Bridges ◽

Bridge Construction ◽

Main Cable ◽

Analytical Algorithm ◽

Tensile Forces

During the construction of suspension bridges, the stress state of the pylon (tower) is improved by pushing the pylon saddle by an appropriate distance at the proper time. An analytical algorithm for the assessment of the required timing and displacements for the pylon saddle pushing at particular construction stages is proposed and verified in this study. The timing calculation is based on the assessment of current hanger tensile forces at each construction stage and the pylon stress state, while the pushing distance/displacement is derived from the conditions of elevation difference closure and the conservation of unstrained length of the main cable segments. This algorithm was successfully applied during the construction of a particular suspension bridge in China with a main span of 730 m. The results obtained strongly indicate that the bending moment in the pylon bottom is contributed by both horizontal and vertical forces of the main cable. The horizontal constituent is dominant and its share gradually increases in the bridge construction process. In a suspension bridge with side spans of various lengths, the stresses in the pylon bottom on the side with a larger side span is more likely to exceed the limit. Therefore, the respective strength criterion controls the pylon saddle-pushing schedule. The proposed analytical algorithm is quite straightforward and is recommended for wider application.

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STATIC ANALYSIS AND SIMPLIFIED DESIGN OF SUSPENSION BRIDGES HAVING VARIOUS RIGIDITY OF CABLES

Journal of Civil Engineering and Management ◽

10.3846/jcem.2010.41 ◽

2010 ◽

Vol 16 (3) ◽

pp. 363-371 ◽

Cited By ~ 20

Author(s):

Tatjana Grigorjeva ◽

Algirdas Juozapaitis ◽

Zenonas Kamaitis

Keyword(s):

Static Loading ◽

Suspension Bridge ◽

Suspension Bridges ◽

Design Procedures ◽

Suspension Systems ◽

Main Cable ◽

Composite Section ◽

Internal Forces ◽

Standard Section ◽

Main Cables

Increased deformability can be considered as the basic disadvantage of suspension bridges. One of the ways to increase the rigidity of a suspension bridge is to transfer a part of stiffening girder rigidity to a suspension main cable. To give the suspension bridge more stable appearance, the authors propose to use the cables of varying bending stiffness. The main cables can be made of standard section shapes or have a composite section. The object of this work was to study a method for analyzing and determining the internal forces in the main cables and stiffening girder under static loading to provide recommendations for designing suspension bridges with stiffened cables. Simple formulas are presented for determining displacements, internal forces and stresses in the main cable and stiffening girder. Finite element modeling was performed. The final part of the paper discusses design procedures for such suspension systems. An example of a pedestrian suspension bridge is appended. Santrauka Esminis kabamuju tiltu trūkumas ‐ didelis ju deformatyvumas. Deformatyvumui sumažinti autoriai siūlo dali standumo sijos lenkiamojo standžio perduoti kabamajam lynui. Baigtinio lenkiamojo standumo lynai gali būti daromi iš standartiniu valcuotuju profiliuočiu arba sudetinio skerspjūvio. Šio darbo tikslas ‐ pateikti supaprastinta metodika kabamojo tilto standaus lyno ir standumo sijos elgsenos analizei atlikti bei rekomendacijas tokiems statiškai apkrautiems tiltams projektuoti. Pateiktos paprastos formules lyno ir sijos poslinkiams, iražoms ir itempiams apskaičiuoti. Atliktas kabamosios tilto siste‐mos modeliavimas baigtiniais elementais. Aptartos tokiu kabamuju tiltu projektavimo procedūros. Pateiktas pesčiuju via‐duko kabamuju konstrukciju projektavimo pavyzdys.

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Application of Flexibility Method to a Chain Suspension Stiffening Beam Bridge

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.255-260.1220 ◽

2011 ◽

Vol 255-260 ◽

pp. 1220-1224

Author(s):

Wen Jie Niu ◽

Zhen Yu Wang

Keyword(s):

Suspension Bridge ◽

Main Beam ◽

Live Load ◽

Structural Members ◽

Equilibrium Equations ◽

Actual Structure ◽

Influence Line ◽

A Chain ◽

Beam Bridge ◽

Main Bridge

This paper intended to determine the influence line for structural members in a Chain Suspension Stiffening Beam Bridge (CSSBB). In an engineering case, flexibility method determined the redundant bar force in CSSBB as the unit live load stayed at different positions on the main bridge beam. These calculated redundant bar forces composed the influence line. The foregoing flexibility method considers suspenders deformation. Results indicate that redundant bar force is maximal when the unit live load stays at the main beam midpoint in Figure 2. The redundant bar force in Figure 3 is the actual force in bar 3 in the actual structure in Figure 2. The redundant bar forces and internal load equilibrium equations can determine the influence lines for other structural members. Simple-supported Beam Bridge (SSBB) can be constructed easily while and wire (cable) suspension bridge are suitable when the bridge is to cross a wide river. CSSBB and arch bridge demonstrates less deflection and less moment at the beam midpoint than the SSBB.

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Evaluasi Kapasitas Elemen Struktur Eksisting Food Court Untuk Perencanaan Cinemaxx Mal Pekanbaru

JURNAL SAINTIS ◽

10.25299/saintis.2020.vol20(02).5514 ◽

2020 ◽

Vol 20 (02) ◽

pp. 77-84

Author(s):

Rony Ardiansyah

Keyword(s):

Bending Moment ◽

Beam Deflection ◽

Live Load ◽

Structural Elements ◽

Support Section ◽

Floor Slab ◽

Beam Elements ◽

Structural Capacity ◽

Live Loads ◽

Internal Forces

[ID] Evaluasi Kapasitas Struktur Eksisting Area Food Court seluas 1024m2 yang dialihfungsikan sebagai Cinemaxx. Penelitian ini dimaksudkan untuk mengetahui kapasitas izin dari elemen struktur eksisting pada elemen balok dan pelat lantai dengan memberikan beban hidup beragam. Struktur dimodelkan dengan menggunakan bantuan program ETABS 2015 untuk menganalisis gaya dalam pada elemen balok. Sedangkan untuk menganalisis gaya dalam pada elemen pelat menggunakan bantuan program SAP 2015. Adapun area yang ditinjau pada evaluasi ini yaitu pelat lantai-3 As-J s/d As-R dan As-2 s/d As-5. Hasil evaluasi menunjukkan bahwa pelat lantai eksisting pada bentang X dengan dan tanpa memperhitungkan defleksi balok, dinyatakan aman (OK) untuk beban hidup 400 & 500 kg/m2, untuk beban hidup 600 kg/m2 dinyatakan KRITIS dan untuk beban hidup 700 kg/m2 dinyatakan tidak aman (NO-OK). Pada pelat lantai, pelat bentang Y hanya beban hidup 400 kg/m2 yang dinyatakan aman (OK), beban hidup 500 kg/m2 dinyatakan KRITIS, dan beban hidup 600 kg/m2 dinyatakan tidak aman (NO-OK). Pelat lantai tanpa memperhitungkan pengaruh defleksi dari balok sekelilingnya atau dengan asumsi pelat sebagai beban, untuk semua beban hidup nya mulai dari 400, 500 dan 600 kg/m2 dinyatakan aman (OK). Momen lentur balok induk 350 x 650 pada tumpuan dinyatakan aman (OK) untuk semua beban hidup mulai dari 500 kg/m2 s/d 800 kg/m2. Sedangkan area lapangan dinyatakan (OK) untuk beban hidup 500 & 600 kg/m2; untuk beban hidup 700 kg/m2 dinyatakan tidak aman (NO-OK). [EN] The evaluation of existing food court structural capacity with area size 1024m2 planned to be transformed to Cinemax. This research is purposed to determine permit capacity of existing structural elements on the beam and slab elements by providing various live loads. The structure is modeled using the ETABS 2015 program to analyze the internal forces on the beam elements. Then to analyze forces within slabs structures were modeled using the SAP 2015. The area covered in this evaluation is the floor slab-3 column centre J-R, and 2-5. The evaluation show for floor slab case in x-axis span, ignoring deflection of the beam, in response to 400 - 500 kg/m2 live load is considered to be safe (OK), 600 kg/m2 live load is considered to be critical, 700 kg/m2 live load is cosidered to be unsafe (NO-OK). In y-axis span, in response to 400 kg/m2 live load, it is considered safe (OK), 500 kg/m2 live load is considered critical, 600 kg/m2 live load is considered unsafe (NO-OK). All slabs assumed as its sole load without putting beam deflection into equation are considered safe in response to 500 - 600 kg/m2 live load. For main beams case (350x650), bending moment in support section is considered to be safe (OK) in all case of live load ranging from 500 - 800 kg/m2. While bending moment in midspan section, in response to 500-600 kg/m2 live load is considered to be safe (OK), 700 kg/m2 live load is considered to be unsafe (NO-OK).

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