Dynamic Characteristics of a Double-Pylon Cable-Stayed Bridge with Steel Truss Girder and Single-Cable Plane

The dynamic characteristics are closely linked to the seismic stability and wind-resistant of the bridge. But different bridge types have different dynamic characteristics. In order to study the dynamic characteristics of a double-pylon cable-stayed bridge with a single-cable plane and steel truss girder whose main span is the longest in the world, the dynamic load test was done, and the finite element and the subspace iteration methods were used to analyze the vibration mode of the bridge. The influence of different structural parameters on the dynamic characteristics of the bridge was analyzed. The changed structural parameters are cable layout, stiffness of steel truss girder, stiffness of stayed cables, stiffness of pylons, the concentration of dead load, number and location of auxiliary piers, and structural system. The results show that the bending and torsion resistance of the double-pylon cable-stayed bridge with a single-cable plane and steel truss girder is weak. The torsional stiffness of the cable-stayed bridge with a double-cable plane is stronger than that of the cable-stayed bridge with a single-cable plane. The seismic stability and wind-resistant of the bridge can be improved by using light dead load, improving the stiffness of pylon and girder, and adding auxiliary piers scientifically. However, the change of cable stiffness has a complex influence on the dynamic characteristics of the bridge. The conclusion can offer references for the construction, maintenance, and design of the same type of bridges.

Design Calculation for A (G +10) Building (Encode Steel)

The proposed steel building at Mumbai consisting of G+10 storeys, has a built-up area of about 165m2. The typical floor height is 3m above GL and the total height of the building above GL is 33m.Withreference to given plan, the architectural drawings and structural drawings showing plan, elevation, sectional views and connection drawings are drawn by using AUTOCAD 2017.Design calculations (Dead Load, Live Load, Wind Load, Seismic Load) are calculated manually-As per IS codes which are mentioned in technical details. The rolled steel sections for beam and column has been chosen from IS 12778:2004. High tensile steel grade-E350BR has been used for steel sections. And, the analysis of structure is done by using STAAD.Pro V8i SS5.Design of beam and column are manually calculated-As per IS: 800-2007. And, spread sheet has been created to check the beam and column, whether it is safe or not. The connection designs are calculated-As per IS codes by using Welding-As per IS 9595-1996 and Fasteners-As per IS 3757-1985. Bracings are provided in the ground floor between the column to avoid soft storey failure. The material requirements are mentioned based on the design calculations. The total estimation of the building is 1.11cr.

Comparative Study Of Conventional Slab, Flat Slab And Grid Slab Using ETABS

In today’s construction, the traditional slab is mostly supported by a beam, with a small slab thickness and a large beam depth, and the weight is carried from beam to column. The flat slab allows architects to place partition walls wherever they are needed. It is widely used because it reduces weight, speeds up building, and is cost effective. Similarly, since its inception, the conventional slab has provided benefits such as increased stiffness, increased weight carrying ability, as well as being safe and cost effective. Grid slabs are necessary where the span is greater, and grid beams are provided to lessen the spanning. Grid slabs reduce dead load due to voids and are appropriate for longer spans with heavy loads. The Grid slab is less expensive and provides superior vibration resistance. The project’s goal is to find the most cost-effective slab among standard slab, flat slab with drop, and grid slab. A G+5 Commercial multi-story structure with flat slab, conventional slab, and gird slab was investigated for characteristics such as storey displacement, shear force, bending moment, and storey drift in this study. There are a total of 18 structures examined. The performance and behaviour of all structures in India’s seismic zone III have been investigated with the application of dead load, live load and seismic load. The results of shear force, Bending Moment, story shear, story displacement, story drift and quantity of concrete and steel shows that the overall result values makes flat slab a suitable structure as compared to the conventional and grid slab.

Comparative Analysis of Structure with and without Seismic Load

Engineers are mostly adopting complex non-linear methods to research multi-storey residential apartment structure to withstand earthquake forces. This paper uses much simpler Equivalent Static method to analyse G+5 storey structure to repel earthquake forces using Staad pro software. The seismic analysis is further compared with non-seismic analysis of an equivalent structure using dead load + super load combination. it had been observed that the seismic results obtained consisted of significantly increased maximum moments and shear forces than the non-seismic analysis From past earthquakes it is proved that many of structure ar completely or partly broken because of earthquake. So, it’s a necessity to figure out unstable responses of such structures. The main aim of the present work is to make a comparative study of seismic and non-Seismic structure. The analysis was performed as per the specification of IS codes IS 1893, IS 875, IS 456:2000.

A comparative study of several bio-inspired algorithms in cost optimization of cellular beams

Castellated beams are commonly used in steel construction. This study will focus on castellated beams with circular-shaped openings, which are known as cellular beams. Cost optimization of cellular beams is needed to maintain cost efficiency. The optimization considers the selection of a root beam, the diameter of holes, and the total number of holes in the beam as the variables. Four metaheuristic algorithms are used to optimize the design, namely, the particle swarm optimization (PSO), differential evolution (DE), symbiotic organisms search (SOS), and artificial bee colony (ABC). A four-meter span beam with a 50 kN point live load in the middle of the beam and a 5 kN/m uniformly-distributed dead load are taken as the case study. The results indicate that the SOS algorithm yields the best optimization results in terms of the average, consistency, and convergence behavior with a 30 out of 30 success rates.

Performance of a Cold Formed Steel Pedestrian Bridge under Static and Dynamic Loads

This paper summarizes new application of CFS in bridge constructions where a seven meters long pedestrian bridge was constructed. The bridge has 1.2m width, 0.8m depth, and is composed of CFS Warren truss and bondek floor systems. Natural frequency of the bridge considering only dead load application was found as 8.54 Hz and decreased to 7.08 Hz when the live load was included. Under static load test, the application of dead load only and both dead and live loads yielded a maximum deflection of 3.53 and 8.1 mm, respectively. Normal walking and running pedestrian loads were carried out created a maximum acceleration equaled to 0.11g. Lastly, sinusoidal waves application facilitated through a three-phase induction motor having self-weight of 24.86 kgf at frequency equal to 8.5 Hz was performed for one hour resulting no decrease of the natural frequency, thus the bridge can be assumed to experience no noticeable stiffness degradation.

STUDI KASUS KEMIRINGAN GEDUNG 4 LANTAI AKIBAT KEGAGALAN FONDASI DI PANGKAL PINANG

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.

Finite Element Analysis of I-Girder Bridge

In India railway bridge structures are widely designed with the method suggested by IRS – Concrete bridge code 1997.This Code of Practice applies to the use of plain, reinforced and prestressed concrete in railway bridge construction. It covers both in-situ construction and manufacture of precast units. The Code gives detailed specifications for materials and workmanship for concrete, reinforcement and prestressing tendons used in the construction of railway bridges. After defining the loads, forces and their combinations and requirements for the limit state design, particular recommendations are given for plain concrete, reinforced concrete and prestressed concrete bridge construction. The design of I-Girder bridge superstructure (deck slab and PSC I-beam) are done by calculating bending moments, shear forces, bending resistance in transverse direction, bending resistance in longitudinal direction, checking flexural cracking. The Design of PSC I-Girders is done for Bending moments and Shear forces by Dead Load, Super Imposed Dead Load (SIDL) and Live Loads (LL). The Shrinkage strain, Creep Strain and effect of Temperature rise and fall are also determined. The design is complete for Pre-stressing cables, un-tensioned reinforcements, End cross girder, Shear connectors. I-girder superstructures are the most commonly used superstructures at cross-over location in metro bridges in india, as it has the wide deck slab and it easily permits metro’s to change tracks. I-Girder superstructure construction is component wise construction unlike U-Girders. I-Girders are constructed in casting yard and its deck slab is cast in situ, parapets are also installed on later stage. Keywords: SIDL effects, Live Load effects, Derailment effect, with or without 15% future PT margin

Coupled Field Analysis of a Chimney Used in Cement Industry

Chimney, which shape the ultimate factor of a machine using a flue fuel consisting of boiler, play a vital function in maintaining performance, draft, and many others, of a gadget and additionally in minimizing the atmospheric pollution. Metal chimneys also are called steel stacks. The metallic chimneys are product of metal plates and supported on basis. The steel chimneys are used to get away and disperse the flue gases to this sort of height that the gases do not contaminate surrounding. In this thesis, chimney can be designed thinking about dead load and wind load. The bureau of Indian requirements (BIS) layout codes techniques can be used for the design of the chimney. The chimney turned into considered as a cantilever beam with annular cross segment. 3-D version of the chimney is finished in pro/engineer and matched area analysis is accomplished on the chimney in ANSYS. A simplified model of chimneys with various thicknesses like 10mm, 12mm, 14mm and 16mm were modeled environment. Keywords: Chimney, Flue Gases, Coupled Field Analysis