Structural Engineering Commons^™

Two-Class Classification With Various Characteristics Based On Kernel Principal Component Analysis And Support Vector Machines, Ivanna Kristianti Timotius, Iwan Setyawan, Andreas Ardian Febrianto

Makara Journal of Technology

Two class pattern classification problems appeared in many applications. In some applications, the characteristic of the members in a class is dissimilar. This paper proposed a classification system for this problem. The proposed system was developed based on the combination of kernel principal component analysis (KPCA) and support vector machines (SVMs). This system has been implemented in a two class face recognition problem. The average of the classification rate in this face image classification is 82.5%.

Investigation Of The Behavior Of Free-Standing Gabions In Seismic Regions, Amy Ransom

Master's Theses

This thesis investigates the behavior of free-standing gabion walls in areas of mild seismicity. To investigate this behavior, three walls of varying internal cable patterns were constructed at a quarter-scale. These walls were tested with a mass shaker, and mode shapes, tone extractions, and damping ratios were calculated. A modal analysis was conducted using design spectra created from a suite of seven earthquakes from countries bordering Kenya. The corresponding lateral forces to these spectral displacements were found, and the restoring eccentricities from the soil restoring force were backed out through a summation of moments. All analysis was experimentally done due …

Asce 7–05 Design Rule For Relative Strength In A Tall Buckling-Restrained Braced Frame Dual System, Lisa J. Aukeman

Master's Theses

In mid- to high-rise structures, dual systems (DS) enable a structural designer to satisfy the stringent drift limitations of current codes without compromising ductility. Currently, ASCE 7-05 permits a variety of structural systems to be used in combination as a dual system yet the design requirements are limited to the following statement: Moment frames must be capable of resisting 25% of the seismic forces while the moment frames and braced frames or shear walls must be capable of resisting the entire seismic forces in proportion to their relative rigidities.

This thesis assesses the significance of the 25% design requirement for …

Corrosion-Resistant Glasses For Steel Enamels, Richard K. Brow, Signo Tadeu Dos Reis, Michael L. Koenigstein, Genda Chen

Materials Science and Engineering Faculty Research & Creative Works

A cementitious composite material wherein glass-coated steel rods are positioned in a cementitious matrix. The glass composition for coating the steel reinforcing rods includes between about 33-45 weight percent SiO₂, 13.5-19.5 weight percent B₂O₃, 3.5-4.6 weight percent Al₂O₃, 4.0-13.5 weight percent K₂O, 5.5-15.5 weight percent ZrO₂, 8.6-15.9 weight percent Na₂O, 4.6-5.1 weight percent CaO, 0.6-0.7 weight percent MnO₂, 1.0-1.0 weight percent NiO, and 1.0-1.1 weight percent CoO. The glass composition is typically in compression on the rods at ambient temperatures, has a …

Design Guide For Cold-Formed Steel Purlin Roof Framing Systems, American Iron And Steel Institute (Aisi)

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

"The Design Guide for Cold-Formed Steel Purlin Roof Framing Systems provides information for the designer of single span and continuous multiple span steel purlin-supported roof systems with an emphasis on the design anchorage systems. The Design Guide is based on the American Iron and Steel Institute (AISI) North American Specification for the Design of Cold-Formed Steel Structural Members, 2007 Edition. Where the Specification is silent on design issues, the procedures are based on published references and on the opinions of the authors.

The Design Guide was co-sponsored by the American Iron and Steel Institute (AISI) and the Metal Building …

Development Of An Open Source Bridge Management System, Michael H. Scott

TREC Final Reports

A bridge management system is developed using the Tcl scripting language in conjunction with the OpenSees finite element software framework. Fully programmable and string-based, Tcl is ideal for implementing live load analysis through scripts and experimenting with emergent bridge rating methodologies. Since Tcl is an interpreted language, the application also has the important advantage that new bridge capacity models and rating factor calculations can be implemented on multiple platforms without compiling source code. The network programming features of Tcl give the system access to databases for conducting internet-based bridge rating. The system is demonstrated for rating a conventionally reinforced concrete …

Calibration Of Load And Resistance Factors In Lrfd Foundation Design Specifications, Zuocai Wang, Genda Chen, Oh-Sung Kwon, Sarah Orton

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This report summarizes the findings and recommendations on the impact of foundation settlements on the reliability of bridge superstructures. As a collaborative effort of an overall initiative for the development of LRFD foundation design specifications, this study is focused on the investigatio of pros and cons for including foundation settlements in bridge designs under gravity loads. Settlement was modeled both probabilistically and deterministically. In the case of a random settlement variable, a lognormal distribution was used in reliability analysis with a fixed coefficient of variation of 0.25. Dead and live loads were modeled as random variables with normal and Gumbel …

A Proposed Data Qualification Procedure For The Connecticut Bridge Monitoring Network, Stephen R. Prusaczyk

Master's Theses

No abstract provided.

Motivating Technical Writing Through Study Of The Environment, J. Linsdell, Thalia Anagnos

Faculty Publications

No abstract provided.

A Parametric Study Of Pedestrian Vertical Force Models For Dynamic Analysis Of Footbridges, Paul Archbold, Joe Keogh, Colin C. Caprani, Paul Fanning

Conference papers

Footbridge vibration has received much attention in recent years. However, stochastic models for crowd loading are not common, and estimation of crowd-induced vibration is typically done through enhancement factors applied to single pedestrian loading models. This work compares two such models, a moving force model and a spring-mass-damper model (SMD). Typical ranges for various pedestrian parameters are examined, and it is found that the pacing frequency has by far the greatest influence on bridge vibration response. It is also found that the magnitude of the response for pacing frequencies near the bridge natural frequency is lower for the SMD model, …

Modelling Of Highway Bridge Traffic Loading: Some Recent Advances, Bernard Enright, Colin C. Caprani, Eugene J. Obrien

Conference papers

The accurate estimation of site-specific lifetime extreme traffic load effects is an important element in the cost-effective assessment of bridges. In recent years, the improved quality and increasing use of weigh-in-motion technology has meant that better quality and larger databases of vehicle weights are now available. This has enabled measurements of the regular occurrence of extremely heavy vehicles, with weights in excess of 100 t. The collected measurements have been used as the basis for building and calibrating a Monte Carlo simulation model for bridge loading. The computer programs written to implement this model generate simulated traffic in two lanes …

Modeling Same-Direction Two-Lane Traffic For Bridge Loading, Eugene J. Obrien, Bernard Enright

Articles

Many highway bridges carry traffic in two same-direction lanes, and modeling the traffic loading on such bridges has been the subject of numerous studies. Different assumptions have been used to model multiple-presence loading events, particularly those featuring one truck in each lane. Using a database of weigh-in-motion measurements collected at two European sites for over 1 million trucks, this paper examines the relationships between adjacent vehicles in both lanes in terms of vehicle weights, speeds and inter-vehicle gaps. It is shown that there are various patterns of correlation, some of which are significant for bridge loading. A novel approach to …

Behaviour Of Unbonded Post- Tensioned Segmental Box Girders With Dry Joints, Michael Matson

Theses

The primary objective of this thesis is to examine the capacity of shear keys used in dry jointed precast post-tensioned segmental box girder bridge construction. The use of dry joints, in lieu of the more traditional glued joints, is becoming more popular in climatically suitable countries. The time and cost savings achieved using this construction form arc significant, due to the economies of scale involved.

The shear capacity of dry jointed keys is calculated using a number of available formulae. However, in previously published papers, significant differences have been noted in the results obtained from these formulae, deeming further investigation …

Bond Behavior Of Fiber Reinforced Polymer Bars Under Hinged Beam Conditions, Ryan James Sandstrom

Master's Theses

The research provided in this report examines the behavior of fiber reinforced polymer (FRP) reinforcing bars, embedded in normal weight concrete (NWC) hinged beam-end specimens, tested in accordance with two laboratory conditions. Reinforcing bars of different diameter, material configuration, and finished surface preparation were tested for bond strength parameters determined in accordance with ACI Committee Report 440.3. Bond strength parameters under the first condition were tested within NWC beams at a relatively low compressive strength and minimum embedment length; the second condition allowed testing within NWC beams at twice the design compressive strength of the first condition and moderate embedment …

Rubble-Mound Structure Design In The Coastal Environment, Jack Murphy

Theses

The main aims of this thesis were to investigate the main aspects of the design and implementation of rubble-mound structures as a form of shoreline stabilisation and coastal defence. An emphasis has been placed on the Irish context of how these structures have been implemented in the past. The intention was that this work would improve the understanding of the use of these structures for future projects both in Ireland and internationally.

This work required a literature review which investigated the general aspects of rubble-mound structures, the coastal environment, and the theory of designing the structures’ layout, cross-section and impact …

A Wireless System For Crack Monitoring In Concrete Structures, Souhail M. Saad

Dissertations and Theses @ UNI

The formation of cracks in concrete is a normal phenomenon. However, effective control and prevention of the formation of cracks is the key for successful life of concrete structures. Specifically, cracks represent a path of least resistance for moisture and corrosive ionic agents from de-icing salts to reach embedded steel in concrete. Commercial wireless sensor networks utilizing crack gauge sensors can be applied for crack monitoring in the common concrete structure. The crack sensors circuits' boards, which are used to stimulate the cracks, are currently unavailable for the SG-Link module platform.

The SG-Link module is an ultra-low-power module for use …

Characteristic Vertical Response Of A Footbridge Due To Crowd Loading, Colin C, Caprani, Joe Keogh, Paul Archbold, Paul Fanning

Conference papers

The characteristic vertical vibration of a flexible footbridge subject to crowd loading is examined in this paper. Typically, bridge vibrations produced from a crowd of pedestrians are estimated by using an enhancement factor applied to the effect caused by a single pedestrian. In this paper, a single pedestrian model, represented by a spring mass damper, which incorporates variables such as pedestrian mass and body stiffness, is used to calibrate a computationally efficient moving force model. This calibrated moving force model is further used in Monte Carlo simulations of non-homogenous crowds to estimate characteristic vertical vibration levels. Enhancement factors, which could …

Modeling Extreme Traffic Loading On Bridges Using Kernel Density Estimators, Cathal Leahy, Eugene J. Obrien, Bernard Enright

Conference papers

Kernel density estimators are a non-parametric method of estimating the probability density function of sample data. In this paper, the method is applied to find characteristic maximum daily truck weights on highway bridges. The results are then compared with the conventional approach

High-Strength Selfconsolidating Concrete Girders Subjected To Elevated Compressive Fiber Stresses, Part 2: Structural Behavior, Jared E. Brewe, John J. Myers

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The design of prestressed concrete members is restricted by the requirement that the extreme compressive fiber stress at midspan be less than 60% of the concrete compressive strength at release of prestressing. the purported purpose of this limit is to provide serviceability performance, but it places unnecessary limits on the capability of the materials. for this research program, six prestressed concrete girders were produced with high-strength, self-consolidating concrete and subjected to elevated compressive fiber stress levels ranging from 65% to 84% of initial concrete compressive strength at release of prestressing. Part 1 of this series analyzed time-dependent prestress losses and …