Structural Engineering Commons^™

Design Of Gan-Based Low-Loss Y-Branch Power Splitter, Retno Wigajatri Purnamaningsih, Irma Saraswati, Nji Raden Poespawati, Elhadj Dogheche

Makara Journal of Technology

We present a Y-branch power splitter design with a multimode section using GaN on Sapphire at telecommunication wavelength. The GaN sample optical properties were also investigated, resulting in a refractive index for the GaN layers nTE=2.289±0.001 and nTM=2.324±0.00. Optimization of the structure parameters for this structure was conducted accurately using BPM methods. The results demonstrated the possibility of realizing a GaN-based Y-branch power splitter for various applications.

Ultra-Wideband Notched Characteristic Fed By Coplanar Waveguide, Rastanto Hadinegoro, Yuli Kurnia Ningsih, Indra Surjati

Makara Journal of Technology

In this paper, a novel Ultra-Wide Band (UWB) notch patch antenna with co-planar waveguide (CPW) fed is presented. This antenna only used one layer and the patch antenna is constructed on the first layer and back to back with CPW fed and bottom part is ground plane. The width notch is used to achieve the UWB characteristic. The results shown that the impedance bandwidth is 1130 MHz (1.662–2.792 GHz) or about 50.7% for VSWR <2.

Development Of The Soekarno–Hatta International Airport Rail Link Project Using The Value Engineering Method: Creating Value For Money, Mohammed Ali Berawi, Bambang Susantono, Suyono Dikun, Tommy Ilyas, Herawati Zetha Rahman, Abdur Rohim Boy Berawi, Teuku Yuri Zagloel, Perdana Miraj, Jade Sjafrecia Petroceany

Makara Journal of Technology

Soekarno–Hatta Airport is the main gateway for international flights to Greater Jakarta. Its accessibility depends on the inter-city and Sedyatmo toll roads, which causes congestion in peak hours, leading to uncertainty about travel times. The Soekarno–Hatta International Airport Rail Link (SHIARL) is proposed as an alternative mass transportation project, which is expected to provide accessibility and mobility for people and goods to and from the airport. Previously, the project was unattractive to private investors as it was technically and financially unfeasible. Therefore, this research aims to improve the feasibility of the Soekarno-Hatta International Airport Rail Link (SHIARL) by using a …

The Mechanical And Tribology Properties Of Sputtered Titanium Aluminum Nitride Coating On The Tungsten Carbide Insert Tool In The Dry Turning Of Tool Steel, Esmar Budi, Mohd. Razali Bin Muhamad, Md. Nizam Bin Abdul Rahman

Makara Journal of Technology

The effect of the sputtering parameters on the mechanical tribology properties of Titanium Aluminum Nitride coating on the tungsten cabide insert tool in the dry turning of tool steel has been investigated. The coating was deposited using a Direct Current magnetron sputtering system with various substrate biases (-79 to -221 V) and nitrogen flow rates (30 to 72 sccm). The dry turning test was carried out on a Computer Numeric Code machine using an optimum cutting parameter setting. The results show that the lowest flank wear (~0.4 mm) was achieved using a Titanium Aluminum Nitride-coated tool that was deposited at …

Continuous Production Of Nanotubes And Carbon Clusters By Use Of The Revolver-Injection-Type Arc Jet Producer, Tetsu Mieno, Naoki Matsumoto, Takahashi Tomie, H. Inoue

Makara Journal of Technology

Efficient and continuous production of fullerenes, single-walled carbon nanotubes (SWNTs), and carbon nano-particles has been developed by the JxB arc jet method, where the Lorentz force of magnetic field jets out gaseous carbon particles to the JxB direction. In order to realize continuous mass production of these carbon clusters, the revolverinjection- type arc jet producer (RIT-AJP) has been developed. Production of fullerenes, endohedral metallo-fullerenes, SWNTs, metal-encapsulated carbon nano particles has been examined.

Analysis Of Vibration Generated By The Rubbing Of Flat Surfaces, Zahrul Fuadi

Makara Journal of Technology

Among the phenomena that occur as a result of contact between two surfaces is friction sound, in which surface roughness is of great importance. In this study, the parameter of contact stiffness is used to explain the frequency characteristic of vibration generated by the rubbing of flat surfaces under a small load. A 3-disk configuration rubbing method was used, which provides a unique characteristic of the system's frequency response function containing specific information about the rubbing vibrations. It is shown that the peak frequency of the rubbing vibration can be explained by using a two-degrees-of-freedom model incorporating the parameter of …

Modified Design Of Pin-On-Ring Tribometer For Hip Joint Prostheses Measurement; Case Study On Salat Activity, Muhammad Khafidh, Jamari Jamari, Sulardjaka Sulardjaka, Mohamad Tauviqirrahman, Emile Van Der Heide

Makara Journal of Technology

Total hip replacement (THR) is one of the most successful orthopedic surgical procedures for replacing a broken hip joint. In THR, wear may occur at the articulating surface of the acetabular cup and the femoral head. In Indonesia, the country with the largest Muslim population in the world, most of the inhabitants do salat (praying) every day. THR users are banned from doing salat for fear it will damage the hip joint prostheses. The previous wear calculation methods on the hip joint prostheses use the gravimetric, coordinate measuring machine (CMM), profiler, and geometric method. The disadvantages of the previous methods …

Endoscopic Application Of A Compact Compound-Eye Camera, Keiichiro Kagawa, Shoji Kawahito

Makara Journal of Technology

A multi-functional compound-eye endoscope enabling multi-spectral imaging and variable field-of-view is presented, which is based on a compact compound-eye camera called TOMBO (thin observation module by bound optics). Narrow-band filters attached to some lenses provide snap-shot multi-band images. Fixed and movable mirrors are introduced to control the field of view, which realizes several observation modes such as three-dimensional shape measurement, wide field-of-view, and close-up observation.

Lateral Load Resistance Of Laminated Veneer Lumber Sengonwooden Joints With Wooden Dowels, Niken Palaeowati, Ali Awaludin, Suprapto Siswosukarto

Makara Journal of Technology

Analytical models for wooden-doweled joints need to be developed. The objective of this research is to determine whether the strength of wooden-doweled joints can be well predicted by equations developed for steel-doweled joints. In this experiment, various connection parameters, such as dowel diameter, species of the wooden dowel, and angle of joints, are studied. The joint specimens are loaded in a quasi-static state with four replications each. A5% offset diameter method is used to determine the lateral load resistance of the tested joints, while the predictions are evaluated by equations given in Indonesian National Standard (SNI) 7973-2013 and the European …

Vulnerability Functions For Seismic Loss Assessment Of The Modern Multi-Story Buildings In Dubai, Abdul Rahman Abdul Aziz Ashri Hassan

Theses

The rapid developments in the United Arab Emirates along with the repeated seismic activity confirm the significance of planning for the possible damage that may hit earthquake-prone areas in order to mitigate earthquake losses. The contemporary buildings are the most important when estimating the potential losses from earthquakes since they represent concentrated economic and human assets. This study aims at developing vulnerability functions for a wide range of modern building inventory in a highly-populated and earthquake-prone area in the UAE. Ten reference buildings with varying heights from 2 to 100 stories and three different lateral force resisting systems are selected …

Calculation For Moment Capacity Of Beam-To-Upright Connections Of Steel Storage Pallet Racks, Tuo Wang, Xianzhong Zhao, Yiyi Chen

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Steel storage pallet rack structures are three-dimensional framed structures, which are widely used to store different kinds of goods. For the easy accessibility to stored products, pallet racks are not usually braced in the down-aisle direction. The down-aisle stability is mostly provided by the characteristics of beam-to-upright connections, and the characteristics of upright base connections. In this paper, calculation for moment capacity of beam-to-upright connections is carried out. A mechanical model is presented firstly. Based on the model, moment capacity is related to the failure capacity, directly determined by the failure mode, of the topmost tab of the beam-end-connector and …

Design Method Of Bending Load-Carrying Capacity For Sandwich Panels With Different Metal Panel On Both Sides, Yanli Guo, Xingyou Yao, Kai Liu

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The sandwich panels, with plain and shallow grain pressed metal plate as the face sheets, and glass wools, rigid polyurethane foam, and rock wools as core materials, have excellent heat insulation and mechanical behavior, and been used as curtain walls for tall buildings in recent years in China. Since wind load and temperature action are the main actions for curtain walls, the sandwich panels are flexural members. In this paper, the design method and design formula of flexural load-carrying capacity and flexural deflection of a kind of sandwich plates with different metal panel on both sides are discussed and proposed. …

Finite Element Modeling Of New Composite Floors Having Cold-Formed Steel And Concrete Slab, Yazdan Majdi, Cheng-Tzu Thomas Hsu, Mehdi Zarei

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

In this research, the structural behavior of a new type of U.S. patented composite floor system is explored through finite element modeling. The new composite floor incorporates cold-formed (light-gauge) steel profiles as the joist on bottom, a corrugated steel deck as the formwork for concrete, a hat channel (furring channel) as the continuous shear connector and finally a concrete slab on top. All steel parts in the system are cold-formed and connected together by self-drilling fasteners. In this study, a comprehensive three-dimensional finite element modeling is performed for the composite floor system. A local bond-slip model is applied to simulate …

Innovative Cold-Formed Steel Framed Shear Wall Sheathed With Corrugated Steel Sheets: Experiments And Dynamic Analysis, Cheng Yu, Guowang Yu, Jie Wang

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Cold-formed steel framed shear wall sheathed with corrugated steel sheets is a promising shear wall system for low- and mid-rise constructions in high wind and seismic zones due to its advantages of non-combustibility, high shear strength, and high stiffness. However recent research projects showed that the corrugated steel sheathing demonstrated low ductility. This paper presents an experimental study aimed at improving the ductility of cold-formed steel shear walls sheathed with corrugated steel sheathing. A method of using opening in the sheathing is employed to improve the shear wall’s ductility meanwhile controlling the damage locations and failure mechanism. A total of …

Bond-Slip Characteristics Between Cold-Formed Metal And Concrete, Yazdan Majdi, Cheng-Tzu Thomas Hsu, Sun Punurai

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Composite action in systems consisting of steel and concrete depends on an effective shear-transfer mechanism between the two materials. Such mechanism for smooth steel surfaces inside concrete will be limited to the bond-slip behavior at the steel/concrete interfaces. This research investigates the bond-slip behavior of galvanized cold-formed (light gauge) steel profiles embedded in concrete. A new innovative pull-out test is presented and global bond-slip curves for different values of concrete strength are obtained from such tests. Next, through an innovative procedure, mathematical equations and a few points from the experimental global bond-slip curves are used to develop a bi-linear local …

Simplified Seismic Design For Mid-Rise Buildings With Vertical Combination Of Cold-Formed Steel And Concrete Framing, X. L. Yuan, L. Xu

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Presented in this paper is a practical approach for the seismic design of mid-rise buildings with vertical combination of cold-formed steel and concrete framing. In current design practice the presence of vertical irregularities on both mass and stiffness inherited in such building structures creates a challenge for the seismic design. Currently, a two stage lateral force procedure prescribed in ASCE 7 is prescribed for evaluating the seismic load if the lateral stiffness of the lower structure of the building is considerably more rigid than the upper one. In the proposed approach the requirement associated with the two stage analysis procedure …

Effect Of Stressed-Skin Action On The Behaviour Of Cold-Formed Steel Portal Frames, A. M. Wrzesien, James B. P. Lim, R. M. Lawson

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper describes six full-scale laboratory tests conducted on cold-formed steel portal frames buildings in order to investigate the effects of joint flexibility and stressed-skin diaphragm action. The frames used for the laboratory tests were of span of 6 m, height of 3 m and pitch of 10⁰; the frame spacing was 3 m. The laboratory test setup represented buildings of length of 9 m, having two gable frames and two internal frames. Tests were conducted on frames having two joint sizes, both with and without roof cladding. It was shown that as a result of stressed-skin diaphragm action, under …

Development Of A Novel Pinned Connection For Cold-Formed Steel Trusses, Chris D. Mathieson, G. Charles Clifton, James B. P. Lim

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Cold-formed steel trusses are a popular form of construction for light-weight buildings, particularly portal frame structures, for which spans up to 25m are increasingly common. In these long span trusses, providing high strength connections with sufficient elastic stiffness is a current limitation to developing cost-effective solutions. A novel pin-jointed truss connection named the Howick Rivet Connector (HRC) has been tested, firstly in a T-joint arrangement, then in a truss assemblage to determine its reliable strength and stiffness. Results showed that the HRC performs similarly to a bolted connection in terms of failure modes observed and loads reached. Additionally, the process …

Fragility Curves For Thin-Walled Cold-Formed Steel Wall Frames Affected By Ground Settlements Due To Land Subsidence, Luis A. Hernández-Castillo, Jose A. Ortiz-Lozano, Martin Hernández-Marín, Jesús Pacheco-Martínez, Mario E. Zermeño-Deleón, Juan J. Soto-Bernal, Jorge Ramos-Ruizflores, Miguel A. Soto-Zamora

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Land subsidence phenomenon due to ground water withdrawal is a current problem in many places around the world, particularly in the shallows of Mexico. This causes ground differential settlements that affect structures, mainly dwellings and buildings based on reinforced concrete and masonry. Eventually, these structural materials do not exhibit an adequate performance beyond a certain level of angular distortion. This work presents the results about a study regarding the performance of thin-walled cold-formed steel wall frames with different sheathing systems affected by angular distortions simulating ground differential settlements due to land subsidence. The wall frames are composed by vertical (studs) …

Investigation On Seismic Performance Of Cold-Formed Steel Portal Frames, Yuanqi Li, Zhijian Xu, Yinglei Li, Yunfei Peng

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

A series of monotonous loading and hysteresis loading tests on cold-formed steel portal frames were conducted in this paper. The averaged ductility factor value of tested frames is 3.15 and the strength and stiffness degradation are not obvious during the test. The failure mode of frame is local buckling at column bases followed by local buckling at the top of columns, which lead to the dropping of frame’s load-carrying capacity. Then, the finite element model is developed and the analysis results match well with the test results. The research in this paper indicates that cold-formed steel portal frame has a …

Effect Of Stressed-Skin Action On Optimal Design Of A Cold-Formed Steel Portal Framing System, Duoc T. Phan, Andrzej M. Wrzesien, James B. P. Lim, Iman Hajirasouliha

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Cold-formed steel portal frames can be a viable alternative to conventional hot-rolled steel portal frames. They are commonly used for low-rise commercial, light industrial and agricultural buildings. In this paper, the effect of semi-rigid joints and stressed-skin action are taken into account in the optimal design of cold-formed steel portal frames. A frame idealization is presented, the results of which are verified against full-scale. A real-coded niching genetic algorithm (RC-NGA) is then applied to search for the minimum cost for a building of span of 6 m, height-to-eaves of 3 m and length of 9 m, with a frame spacing …

Structural Strength Of Lapped Cold-Formed Steel Z-Shaped Purlin Connections With Vertical Slotted Holes, J. Liu, L. Xu, S. Fox

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Lapped joints of cold-formed steel (CFS) Z-shaped purlins are extensively used in metal building roof systems. The research that has been carried out so far for these lapped connections is primarily focused on connections with round holes. However, the lapped connections with vertical slotted holes are extensively used in current construction practice to simplify the erection of continuous Z-shaped roof purlins. There are no design guidelines or recommendations available for CFS Z-purlin lapped connections with vertical slotted holes.

Presented in this paper are the results of an experimental study on the structural strength behaviour of lapped CFS Z-shaped purlin connections …

Direct Strength Method For Ultimate Strength Of Bolted Moment-Connections Between Cold-Formed Steel Channel Members, James B. P. Lim, Gregory J. Hancock, G. Charles Clifton, Cao Hung Pham

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Experimental tests have previously shown that the strength of bolted moment-connections between cold-formed steel members, where the connections are formed through an array of bolts in the web, is dependent on the length of the bolt-group. This reduced strength has been observed in tests on portal frame joints as well as over-lapped purlin joints. For a short bolt-group length, in the order of the depth of the section, this paper shows that a reasonable lower bound to this reduced strength can be predicted by using the Direct Strength Method (DSM), modified to include the effect of the bimoment at the …

Lateral Loading Response Of Cfs Framed Shear Wall With Cement Board Panels, N. Baldassino, M. Accorti, R. Zandonini, F. Scavazza, C. A. Rogers

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Shear wall panels are commonly used as lateral load resisting elements to provide stability of the cold-formed steel-framed houses in Australia against wind and earthquake actions. The effectiveness of their lateral resistance behavior is obtained usually by experimental testing although it can also be done by analytical modeling. This paper presents racking test results of steel-framed wall panels with different aspect ratios sheathed with fibre cement board subjected to monotonic and cyclic loading protocol. Performance parameters of the wall panels are obtained from the experimentally observed load-deflection curves using various existing methods and evaluation method is proposed. The evaluation method …

Evaluation Of The Seismic Performance Of Light Gauge Steel Walls Braced With Flat Straps, Iuorio Ornella, Macillo Vincenzo, Terracciano Maria Teresa, Pali Tatiana, Fiorino Luigi, Landolfo Raffaele

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The development of light weight steel structures in seismic area as Italy requires the upgrading of National Codes. To this end, in the last years a theoretical and experimental study was carried out at the University of Naples within the research project RELUIS-DPC 2010-2013. The study focused on "all steel design" solutions and investigated the seismic behaviour of strap braced stud shear walls. Three wall configurations were defined according to both elastic and dissipative design criteria for three different seismic scenarios. The lateral in-plane behavior of these systems were evaluated by 12 tests performed on full-scale CFS strap-braced stud wall …

Towards Quantifying Beneficial System Effects In Cold-Formed Steel Wood-Sheathed Floor Diaphragms, A. Chatterjee, Y. Xiang, C. D. Moen, S. R. Arwade, Benjamin W. Schafer

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Cold-formed steel wood-sheathed floor diaphragm system behavior is analyzed from a system reliability perspective. Floor systems consisting of oriented strand board (OSB), cold-formed steel (CFS) joists, tracks and screw fasteners are modeled using shell and spring elements in ABAQUS. (Dassault-Systems ())The models consider typical seismic demand loads, with careful treatment of light steel framing diaphragm boundary conditions and OSB sheathing kinematics, i.e., two sheets pulling apart or bearing against each other at an ultimate limit state, consistent with existing experimental results. The finite element results are used to build surrogate mathematical idealizations (series, parallel-brittle and parallel-ductile) for the critical system …

Design Equations For Tensile Rupture Resistance Of Bolted Connections In Cold-Formed Steel Members, Lip H. Teh, Benoit P. Gilbert

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper summarises and re-examines the authors’ previous research results concerning the tensile rupture resistance of cold-formed steel bolted connections in a flat sheet, in a channel’s web, and in one leg of an angle section. Staggered bolted connections are also included. The fundamental shortcomings of the design equations given in the 2012 North American Specification for the Design of Cold-formed Steel Structural Members are described, and the alternative design equations proposed by the authors are shown. The alternative equations are checked against laboratory test results obtained by the authors and other researchers where the bolts had not been snug-tightened …

Strain And Stress Distributions In Composite Deck Slabs: A Numerical Study, Vitaliy V. Degtyarev

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper describes results of a study on strain and stress distributions in compact and slender composite deck slabs using nonlinear three-dimensional finite element models. The slabs were modeled as flexural members made of steel deck units and structural concrete fillings interconnected at the interface with nonlinear springs representing bond between two materials. The models are capable of accounting for partial interaction between the deck and the concrete, discrete concrete cracking in the slab tension zone, and nonlinear behavior of the materials and the interface. They were validated against published test data and have proved to be effective in predicting …

Numerical Investigation Of Cold-Formed Steel Top Hat Purlins, Asraf Uzzaman, Andrzej M. Wrzesien, Robert Hamilton, James B. P. Lim, David Nash

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper considers the use of cold-formed steel top-hat sections for purlins as an alternative to conventional zed-sections. The use of such top-hat sections may be viable for use in cold-formed steel portal framing systems, where both the frame spacing and purlin span may be smaller than in conventional hot-rolled steel portal frames. Furthermore, such sections are torsionally stiffer than zed-sections, and so have a greater resistance to lateral-torsional buckling. They also do not require the installation of anti-sag rods. The paper describes non-linear elasto plastic finite element analyses conducted on top-hat sections. The results of twenty-seven tests on four …

Study On The Flexural Capacity Of Cold-Formed Steel Joists-Osb Composite Floors, X. H. Zhou, Y. Shi, R. C. Wang, Y. J. Liu

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Two full scale specimens were tested to study the flexural capacity of cold-formed steel joists and OSB (Oriented strand board) composite floors. Test results indicated the composite floors had high bearing capacity and small deformation, and the screw spacing significantly affected the load-carrying capacity. The main failure modes were flexural and torsional buckling of floor joist, and the interactive buckling of compression flange, web and crimp. The wave length of bucking equalled to the adjacent screw spacing. Then the specimens were analyzed by commercial software ANSYS and the nonlinear FEM calculation results agreed well with the test results. Furthermore, detailed …