8 Articles Published

1. A STUDY ON THE IMPROVING OF CFT COLUMN’S STRUCTURE AND DURABILITY PERFORMANCE

Authors: DAEGEON KIM , DONGUN LEE

Abstract: This paper investigates the contribution of rib elements attached inner side of CFT for higher bond strength between steel tube and concrete and fire performance with no protections. Test results also present the work of beam’ s shape to fire resistance, the microstructure of concrete and the benefit of a paper drain that can be letting the redundant water out through the holes drilled on the tube plate. Discussions on beam’s design could be followed after some more fire tests accordingly conducted within this investigation.

Keywords: CFT column, tube plate, fire resistance, structure, durability

Pages: 1 - 5 | DOI: 10.15224/978-1-63248-135-1-20

2. DESIGN OF GOLD BASED MEMS ACOUSTIC DIRECTION FINDING SENSOR FOR SMALL ARMS FIRE AND ITS ANALYSIS

Authors: SYED OSAMA BIN ISLAM

Abstract: Acoustic sensors based on MEMS technology is an emerging area of research. Harmonic analysis of these devices is seen to be deliberated recently. The response of a microstructure when subjected to acoustic waves depends upon its geometric properties as well as its material properties; therefore it is important to understand these properties at this level, generally referred to as Meso scale properties. This paper presents the design and modeling of MEMS acoustic sensor optimized for detecting direction of sound at particular frequency range related to small arms fire. Design and FEM modeling is carried out using gold based process design rules. The sensor is modeled with a structural layer of gold with 4.8 μm thickness. The sensor plates’ deflection amplitude varies when the applied pressure and angle of incidence is changed. Moreover, the stresses induced in the sensor, corresponding to the gunshot fire are analyzed to ascertain the fatigue effects.

Keywords: Acoustic Sensor, MEMS, PTM, FEM, Yield Strength .

Pages: 6 - 10 | DOI: 10.15224/978-1-63248-135-1-35

3. BEM ANALYSIS OF RC CRACKED BRIDGE SLABS

Authors: A. KMITA , M.Y. MINCH

Abstract: A. KMITA The purpose of this work is to present some aspects and main problems of theory and computations of RC (reinforced concrete) bridge slabs. The differential equation of the cracked bridge slab, using the classical variational method is worked out. The equation of bridge slab deflection with the boundary conditions and compatibility conditions in the crack are obtained. The total differential equations in the class of the general functions are shown. In this model the effect of discontinuity of the first derivative of deflection functions is taken. The numerical results of an approximate method of solutions of RC cracked plates with boundary element method (BEM) are shown.

Keywords: Boundary Element Method (BEM), analysis, reinforced concrete (rc), crack, slab, bridge

Pages: 11 - 18 | DOI: 10.15224/978-1-63248-135-1-36

4. OUTRIGGER STRUCTURAL SYSTEMS FOR TILTED TALL BUILDINGS

Authors: KYOUNG SUN MOON

Abstract: Structural design of tall buildings is generally governed by lateral stiffness. Outrigger structural systems, which produce lateral stiffness very effectively, are one of the most prevalently used structural systems for today’s tall buildings. With abundant emergence of complex-shaped tall buildings, when the system is employed for twisted or freeform tall buildings, its lateral stiffness is typically reduced compared with the cases when they are used for prismatic tall buildings. However, when the system is employed for tilted tall buildings, its lateral stiffness is increased. This paper studies lateral performance of outrigger structures employed for tilted tall buildings. Parametric structural models are generated using appropriate computer programs for this study, and the models are exported to structural engineering software for design and analyses of tilted outrigger structures of various tilted angles.

Keywords: tilted tall buildings, lateral stiffness, outrigger structures, parametric modeling

Pages: 19 - 21 | DOI: 10.15224/978-1-63248-135-1-37

5. APPLICATION OF ARTIFICIAL NEURAL NETWORKS FOR DEVELOPING A CRACK DETECTION ALGORITHM

Authors: DIVYA VANI B , MANJUNATH N HEGDE , B PRAKRUTHI GOWD

Abstract: As the demand for the safety and functionality of civil structures is increasing continuously, structure health monitoring (SHM) has now become more and more important. Recent developments in artificial intelligence is offering great potentials to develop a more efficient, reliable, and robust structure damage detection system. In this paper, the application of artificial neural networks is investigated and an intelligent structural damage detection algorithm is developed and also an uncertainty study is made to check the robustness of the algorithm developed.

Keywords: Damage Detection, Artificial Neural Network, Sensitivity Analysis.

Pages: 25 - 28 | DOI: 10.15224/978-1-63248-135-1-41

6. DETECTION OF DAMAGE IN A BEAM LIKE STRUCTURE USING WAVELET ANALYSIS

Authors: B PRAKRUTHI GOWD , DIVYA VANI B , MANJUNATH N HEGDE

Abstract: Damage in a structure will adversely affect its current and future performance. Most often the extent and location of damage can be determined through visual inspection. However, in many cases this may not be feasible at initial or later stages. Structural damages may cause local changes in one or more parameters like stiffness, mass and damping that affects the dynamic behaviour of the structure. Modal parameters are sensitive indicators of structural damage. In this paper, the wavelet transform (both continuous and discrete) has been used to detect, locate and find the severity of the damage in a beams like structure which does not require the knowledge of the undamaged state.

Keywords: Damage Detection, wavelet transform, wavelet coefficients

Pages: 29 - 32 | DOI: 10.15224/978-1-63248-135-1-42

7. PERFORMANCE OF ASYMMETRIC SLOT –ENTRY HYBRID JOURNAL BEARINGS

Authors: A. ABDELBADIE , I.M. ELFAHHAM , W.A. CROSBY

Abstract: A comparative study of slot –entry hybrid journal bearings performance with different symmetric and asymmetric geometrical configurations has been presented. The research work includes a numerical analysis of full thermo-hydrodynamic non-recessed slot entry journal bearing. The results show the optimum number of slots for each row of double row symmetric configuration and for single row asymmetric case. The results demonstrated that the optimized asymmetric configuration has higher load carrying capacity especially at high eccentricity ratio. The effect of temperature rise on load carrying capacity of the bearing is more pronounced in symmetric than that in asymmetric configuration. Considering the stability of the bearing, the comparative study indicates that asymmetric geometric configurations have better stability compared to symmetric geometric configurations with higher threshold speed margin.

Keywords: Hybrid Bearing, slot-entry, asymmetric bearing, stability

Pages: 33 - 40 | DOI: 10.15224/978-1-63248-135-1-45

8. STRUCTURAL PERFORMANCE OF VERTICALLY DISTRIBUTED MULTIPLE TUNED MASS DAMPERS IN TALL BUILDINGS

Authors: KYOUNG SUN MOON

Abstract: As today’s tall buildings become ever taller and more slender, wind-induced vibration is a serious design issue. Installing tuned mass dampers (TMDs) is a reliable solution to mitigate wind-induced vibration of tall buildings. This paper investigates structural performance of vertically distributed multiple TMDs along the height of the building. Compared with the conventional TMD system, composed of very large TMD masses installed near the top of the building, much smaller TMD masses are used in the vertically distributed TMD system. Though the performance of the vertically distributed TMD masses is somewhat reduced, the system can still be very effective depending on the range of the distribution. In addition, the valuable spaces near the top of tall buildings can be saved for more desirable architectural functions.

Keywords: tall Buildings, structural motion control, tuned mass damper

Pages: 22 - 24 | DOI: 10.15224/978-1-63248-135-1-38