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Experiment Determination Of Required Lateral Restraint Forces For Z-Purlin Supported, Sloped Metal Roof Systems, Spencer R. Lee, Thomas M. Murray

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

No abstract provided.

Development Of Concrete Qc/Qa Specifications For Highway Construction In Kentucky, Kamyar C. Mahboub, Donn E. Hancher

Kentucky Transportation Center Research Report

There is a growing trend toward quality-based specifications in highway construction. A large number of quality control/quality assurance (QC/QA) specifications shift the responsibility of day-to-day testing from the state DOH to the contractor. This requirement for contractor-performed quality control testing has been partly due to the fact that state agencies are operating with a smaller pool of employees compared to previous years. Another driving force has been the application of performance-based specifications and realization that the contractor and the producer need some degree of flexibility in order to be more efficient and innovative. This report presents the background information behind …

Baseflow Separation Based On Storage-Outflow Modelling Of Streamflow Recessions, With Application To Semi- Arid Catchments In Tanzania, S Mwakalila

Tanzania Journal of Engineering and Technology (TJET)

Discharge in many rivers is Often fed by baseflow provided by drainage of the saturated zone in the shallow permeable soils. It is becoming clear that the outflow from this saturated zone is not linear proportional to storage as is commonly assumed in many algorithms. The objectives Of this study theretore, are first to explore the extent to which the assumption of linearity in storage-outflow relationships is valid and secondly to introduce an alternative approach to baseflow separation algorithms for estimating direct mnoff time series. Numerical analysis Of streamflow recessions from the semi-arid catchments of the Great Ruaha basin in …

Resilient Modulus Of Kentucky Soils, Tommy C. Hopkins, Tony L. Beckham, Charlie Sun, Bixian Ni

Kentucky Transportation Center Research Report

In recent years, the American Association of State Highway Transportation Officials (AASHTO) has recommended the use of resilient modulus for characterizing highway materials for pavement design. This recommendation evolved as of a result of a trend in pavement design of using mechanistic models, which are based on the theory of elasticity (layered elastic analysis) or linear and non-linear, finite elements (and finite difference methods), or a combination of both of those theoretical approaches. Although much progress has been made in recent years in developing mathematical, mechanistic pavement design models, results obtained from those models are only as good as the …

Water Infiltration Study On Slopes, Tian Huat Low

Student Works (2000-2009)

Study was carried out in the field using infiltrometer and in the laboratory using “sprinkler model”. Studies on infiltration have always been part of hydrology and Irrigation engineering. Infiltration forms the link between surface and subsurface hydrology. Infiltrated water must be quantified and subtracted from the surface runoff in flood prediction studies and surface water management. Numerous researchers have actually incorporated infiltration into the slope stability analysis of the residual soils, e.g., Othman (1990), Affendi et. al.(1992, 1996) and Suhaimi and Abdul Rahman (1997). In most analysis of slope stability, the infiltration rate of the slopes is assumed uniform throughout …

Predicting The Integrity Of Existing Prestressed Concrete Bridge Deck Using Sonic Method, Ming-Te Liang, Jyi Wu

Journal of Marine Science and Technology–Taiwan

The principal objective of this paper was provided a general idea for predicting the integrity of existing prestressed concrete bridge decks by using sonic method. The governing equation is a onedimensional wave equation with initial conditions. The method of Fourier transform was adopted for seeking D'Alembert's solution which is an analytical solution of the governing equation. Furthermore, the wave formulae such as displacement, velocity, force and stress waves were derived from the analytical solution. If the viscosity effect of material was neglected, then the elastic wave can be reduced as the sonic wave. Through these sonic wave formulae, the damage …

Analysing Construction Risk : A Project Management Model, P K Dey

IIMB Management Review

The success parameters for any project are ontime completion within the specific budget, and requisite performance or meeting the technical requirements. The main barriers to achievement are changes in the project environment. The problem multiplies with the size of the project. Large-scale construction projects are exposed to an uncertain environment because they are subject to such factors as planning and design complexity, presence of various interest groups (project owner, owner’s project group, consultants, contractors, vendors etc), availability of resources (materials, equipment, funds etc), climatic environment, the economic and political environment and statutory regulations. Other risk factors include the complexity of …

Fractionation & Segregation Of Suspended Particles Using Acoustic And Flow Fields, Nazhat Aboobaker

Dissertations

The fractionation of particles by size or by density has many applications in a variety of technologies. Decontamination and separation of fine sediments is useful in treating sediments. The application of acoustic standing wave fields for the fractionation and segregation of suspended particles was studied.

The above technology was implemented at the bench scale by building a Plexiglas chamber. Two ultrasound transducers were fixed to opposite sides of the chamber to generate the acoustic standing wave field. The technology was evaluated using silica dioxide (Si02) (1-5 ~tm) and silicon carbide (SiQ (5-20 ~tm) particle suspensions in deionized water. Due to …

Transit Productivity Analysis In Heterogeneous Conditions Using Data Envelopment Analysis With An Application To Rail Transit, Manuel J. Martinez

Dissertations

This dissertation extends transit productivity analysis by developing a new method of Data Envelopment Analysis (DEA), the linear programming approach to productivity analysis. The new model analyzes productivity of transit working under heterogeneous operating conditions. It is named Two-Farrell DEA for it applies DEA in two stages, DEA (1), that calculates the productivity frontiers at given operating conditions and DEA (2), that uses inputs adjusted by multipliers calculated in DEA (l). The model Two Farrell DEA calculated productivity benchmarks for each rail transit agency and estimated its potential for higher revenue or lower expense improvement. Additionally, the results identify two …

A Software System For Large-Scale Structural Optimization, Keith M. Macbain

Dissertations

This work is driven by recent developments in mathematical programming, the state-of-the-art of structural optimization, the spectacular performance of linear programming algorithms, and computer hardware developments which imply that applications of structural optimization might be used commonly in engineering design. Currently, there are few general purpose optimization routines available to the structural engineer and much of the work has addressed specific classes of problems. Further, there is little widespread use of the available routines, partly due to the large amount of familiarity one must have with the specific details of both the problem and the optimization method. In response, it …

Using Genetic Algorithms And Swat To Minimize Sediment Yield From An Agriculturally Dominated Watershed, Misgana K. Muleta, John W. Nicklow

Civil and Environmental Engineering

Non-point source pollution is well recognized as one of the most critical environmental hazards of modern times. In Illinois, non-point source pollution is the major cause of water quality problems, and soil erosion from agricultural lands is the major source of such pollution. Accelerated by anthropogenic activities, soil erosion reduces crop productivity and leads to subsequent problems from deposition on farmlands and in water bodies. Watershed management, however, promotes protection and restoration of these natural resources while allowing for sustainable economic growth and development. In this study a discrete time optimal control methodology and computational model are developed for determining …

Statistical Properties Of Maximum Likelihood Estimates For Accelerated Lifetime Data Under The Weibull Model, Mahmoud A. Yousef

Doctoral Dissertations

Pipe rehabilitation liners are often installed in host pipes that lie below the water table. As such, they are subjected to external hydrostatic pressure. The external pressure leads to early deformation in the liners, which could ultimately lead to its failing or buckling before its expected service lifetime is achieved. Experiments involving long term buckling behavior of liners are typically accelerated lifetime testing procedures. In an accelerated testing procedure a liner is subjected to a constant external hydrostatic pressure and observed until it fails or for a certain time, t whichever occurs first. Liners that do not fail at time …

Quality Control Parameters For Robotic Bridge Painting, Yong Bai, Leonhard E. Bernold

Civil and Environmental Engineering Faculty Research and Publications

To protect a steel bridge from corrosion, periodic painting is needed. Bridge painting operations are dangerous and hazardous to human health. A robotic bridge painting system is being developed to replace the human being. One major problem with robotic bridge painting is how to achieve the specified coating quality, which includes two aspects: (1) the coating thickness; and (2) the coating appearance. To ensure quality of the robotic bridge painting, the writers have investigated: (1) the parameters that affect the coating thickness and appearance; (2) the values of the parameters to achieve the required thickness and appearance for the robotic …

Unsteady Flow Model For An Irrigation Canal Network, Talaat Taher El Gamel

Civil & Environmental Engineering Theses & Dissertations

A mathematical model is developed to route unsteady flow through an irrigation canal network. The model is designed to handle branches, lateral inflow and outflow, sluice gates, and various boundary conditions. The model is developed for use on a personal computer. A specific irrigation canal network in Egypt is used as a case study to verify the model, and the results are presented. Full documentation is included in the appendix.

Fourth International Conferences On Recent Advances On In Geotechnical Earthquake Engineering And Soil Dynamics, Multiple Authors

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.

Site Effect Evaluation Using Combination Of Source Scaling Models And Ground Motion Records, Vladimir Sokolov, Chin-Hsuing Loh, Kuo-Liang Wen

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

We analyze site response of the Taipei basin using the records obtained by the Taiwan Strong Ground Motion Instrumentation Program (TSMIP) network. Records of 66 earthquakes of M=2.6-6.5 with a hypocentral depth varying from 1 km to 118 km and hypocentral distances of up to 150 km are studied for 35 stations located within this triangle shaped alluvium structure. The site response is obtained in terms of spectral ratios calculated by dividing of the site spectrum by the reference spectrum estimated for a hypothetical “very hard rock” site. The recently developed empirical source scaling and attenuation models are used for …

Characterization Of Microtremor Records Using Simulated Microtremors, Juan Carlos Tokeshi Nagamine, Yoshihiro Sugimura, Madan B. Karkee

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The paper attempts to illustrate the potential application of simulation techniques for interpretation and characterization of microtremors. Simulations are performed with two types of source distribution models, both involving a large number of Dirac wave type sources randomly activated on the surface of a horizontally layered ground underlain by the half-space. Attempt is made to utilize the technique for the interpretation of microtremors at KASAI site in Chiba prefecture (Japan). The site has a deep base layer and weak impedance contrast. The parameter RF, defined as the ratio between horizontal and vertical input forces at the source, is used as …

Non-Linear Site Response Analysis For Deep Deposits In The New Madrid Seismic Zone, Youssef M. A. Hashash, Duhee Park, Jungsuk Lee

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The New Madrid Seismic Zone, the most seismically active zone in the Eastern US, is overlain by deep unconsolidated deposits of the Mississippi Embayment. The deposits range in thickness from about 20 m in the St. Louis area to about 1 km in the Memphis Area and consist of silts, clays and sands. The influence of these deposits on the propagation of seismic waves to the ground surface remains a major source of uncertainty. A new non-linear one-dimensional site response analysis model is introduced for the vertical propagation of horizontal shear waves in deep soil deposits. The model accounts for …

Study Of Dynamic Bahavior Of Ground Dams With Account Of Moisture Content Under Seismic Actions, B. E. Khusanov, S. I. Umarkhonov

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Ground dams as it is well known have a complex geometry and physical non-uniformity. Dams with inner (central) little-water-saturated obstacle in the form of a so-called core which is formed from little-water-saturated clayey soil are more frequent in Central Asia. Slope zones around this core are of water-saturated stone filled soils. Water infiltration, that is moisture content of soil leads to the change of strength parameters of the core material. Stress-strain state of ground dams is studied in this paper with account of moisture content of clayey parts of the dam on seismic action with records of real velosigrams. Dam …

Investigation Of Seismic Soil-Footing Interaction By Large Scale Tests And Analytical Models, Ezio Faccioli, Roberto Paolucci, Guillermo Vivero

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Recent experimental and analytical research on seismic behavior of shallow foundations is illustrated. The most significant results on the seismic bearing capacity of footings with pseudo-static approaches are reviewed first, including an analytical formula recently proposed for the new version of the “seismic” Eurocode 8. Afterwards, we present the salient experimental results of large-scale cyclic tests of a shallow foundation model (1m x 1m in plan) resting on a large volume of sand, with relative densities 45% and 85%, discussing them in detail. Under earthquake-like cyclic loading, with peak values close to the pseudo-static failure limit, significant permanent settlement and …

Newmarkian Analysis Of Liquefied Flow In Centrifuge Model Earthquakes, S. K. Haigh, S. P. G. Madabhushi, K. Soga, Y. Taji, Y. Shamoto

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

This paper describes the application of a modified Newmarkian analysis method to the estimation of slope deformations during liquefaction-induced lateral spreading. The analysis method requires a pore-pressure history either predicted using a suitable constitutive model, or measured during a centrifuge or shaking-table test, to calculate the variation of threshold acceleration with time. Comparison of predicted displacements using this procedure and displacements measured in centrifuge mode1 tests with the same pore-pressure history shows good agreement.

Shear Strength Reduction Due To Excess Pore Water Pressure, Awad Ali Al-Karni

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Earthquake shaking causes the pore water pressure inside the soil mass to increase rabidly within a short period of time as seconds. As a result, the shear strength of the soil could be reduced significantly. The reduction in the shear strength will increase gradually as the shaking continues due to the gradual increase in the buildup of the excess pore water pressure. At a certain level of shaking, the soil mass will liquefy and could be considered as a viscous fluid. In this paper, a mathematical expression of a reduction factor was derived to estimate the reduction in the shear …

Similarity Rule For Dynamic Model Tests Of Geotechnical Structures, Gao Lin

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Soils and rocks are characterized by their highly nonlinear behaviors. This makes it very difficult to ensure similarity between model and prototype for dynamic model tests of geotechnical structures. In reality, a great number of such tests were carried out qualitatively, and valuable information was missed. Based on fairly long time practice and experience of performing dynamic model tests, we get some new ideas to establish similarity relationships between model and real earth structures. It is noticed that during strongly inelastic shaking, peak crest acceleration of earth and rock-fill dams decreases with increasing base excitation, finally at near failure stage …

Theoretical And Experimental Engineering Analysis For Seismically Damaged Masonry Buildings, Ion Vlad, Mirela-Nausica Vlad

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Romania is one of the countries undergoing a persistent, periodical severe seismic regime, generated by sources of tectonic origin. The strongest earthquakes occurring in our country are of an intermediary, subcrustal (70

General Report— Session 1: Dynamic Properties For Soils Engineering Soil Parameters And Constitutive Relations: New Field And Laboratory Results, V. S. Pillai, B. Muhunthan

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.

General Report — Session 2: Wave Propagation, Engineering Vibrations And Solutions, Vibrations Of Machine Foundations, Blast, Traffic And Construction Vibrations, Vibration Absorption, M. Hesham El Naggar, D. K. Baidya, Dong-Soo Kim, George M. S. Manyando, Nii K. Allotey

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.

General Report — Session 9: Model And Full Scale Tests Of Geotechnical Structures Including Centrifuge Tests, Bruce L. Kutter, S. P. Gopal Madabhushi

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.

Recent Studies On Seismic Analysis And Design Of Retaining Structures, Susumu Iai

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The studies on seismic analysis and design of retaining walls in the recent years have revolved around the wall performance in the near-source zones. Major developments include: (1) the conventional limit equilibrium approach is extended based on the multiple failure plane concept; (2) a set of design charts for evaluating residual horizontal displacement of a gravity wall on yielding foundation are developed based on the parametric effective stress analysis; (3) applicability of the effective stress analysis on the retaining wall performance is confirmed by the case history during Hyogoken-Nambu, Kobe, earthquake; (4) major earthquake motion parameters that govern the wall …

Dam Engineering — Earthquake Analysis, Pedro Simão Sêco E Pinto

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The performance of dams subjected to earthquakes is addressed with particular emphasis of recent earthquakes. Analysis of dams stability during earthquakes by experimental and mathematical models is referred. Foundation studies for soil and rock materials are described and assessment of liquefaction potential is discussed. Selection of design earthquakes by deterministic and probabilistic criteria is presented. Also neotectonics and attenuation relations are described. Monitoring and dam safety during construction and operation are addressed. Reservoir induced seismicity and prototype dynamic tests are treated. Ageing effects and rehabilitation of dams are discussed. Benefits and concerns of dams are referred. Risk analysis is addressed. …

Investigation Of Seismic Soil-Footing Interaction By Large Scale Cyclic Tests And Analytical Models, Ezio Faccioli, Roberto Paolucci, Guillermo Vivero

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Recent experimental and analytical research on seismic behavior of shallow foundations is illustrated. The most significant results on the seismic bearing capacity of footings with pseudo-static approaches are reviewed first, including an analytical formula recently proposed for the new version of the “seismic” Eurocode 8. Afterwards, we present the salient experimental results of large-scale cyclic tests of a shallow foundation model (1m x 1m in plan) resting on a large volume of sand, with relative densities 45% and 85%, discussing them in detail. Under earthquake-like cyclic loading, with peak values close to the pseudo-static failure limit, significant permanent settlement and …