Civil and Environmental Engineering Commons^™

A Modal Pushover Analysis Procedure To Estimate Seismic Demands For Buildings: Theory And Preliminary Evaluation, Anil K. Chopra, Rakesh K. Goel

Civil and Environmental Engineering

The principal objective of this investigation is to develop a pushover analysis procedure based on structural dynamics theory, which retains the conceptual simplicity and computational attractiveness of current procedures with invariant force distribution, but provides superior accuracy in estimating seismic demands on buildings.

The standard response spectrum analysis (RSA) for elastic buildings is reformulated as a Modal Pushover Analysis (MPA). The peak response of the elastic structure due to its nth vibration mode can be exactly determined by pushover analysis of the structure subjected to lateral forces distributed over the height of the building according to s^*_n = …

Enhanced Biodegradation Of Hydrocarbon Contaminants Using Photocatalytic Pretreatment, Chad E. Green, Anita Stansberry, Jeff Sczechowski, Yarrow Nelson

Civil and Environmental Engineering

Photocatalysis was investigated as a pretreatment for hydrocarbon groundwater contamination at an abandoned oil field in Guadalupe, CA. A laboratory photoreactor, with a UV fluorescent lamp submerged in a suspension of TiO₂ catalyst particles, was used to determine oxidation rates and the increase in biodegradability of the hydrocarbon mixture. Chemical oxidation demand (COD) and 5-day biological oxygen demand (BOD₅) were measured as a function of exposure time using standard methods. During eight-hour photoreactor runs in a nitrogen atmosphere, the COD of diluent solutions in de-ionized water and diluent solutions in simulated groundwater both decreased by approximately 50%, …

Environmental Management Of Wastes In The Semiconductor And Electronics Industries, Samuel A. Vigil

Civil and Environmental Engineering

The management of wastes in the semiconductor and electronics industries requires a multidisciplinary approach that considers the health and safety of employees as well as the treatment and recycling of waste materials. The manufacturing of semiconductor devices requires the use of many toxic chemicals and gases. Air emissions from manufacturing tools must be carefully monitored both inside and outside of the fabrication facility. Liquid effluents must be collected and pretreated before discharge to local wastewater systems. The subsequent use and eventual discard of electronic devices such as television sets and personal computers by consumers has created a new set of …

Effects Of Supplemental Viscous Damping On Inelastic Seismic Response Of Assymetric Systems, Cecilia A. Booker, Rakesh K. Goel

Civil and Environmental Engineering

This study investigates the effects of supplemental viscous damping on the seismic response of one-story, asymmetric-plan systems responding in the inelastic range of behavior. It was found that addition of the supplemental damping reduces not only deformation demand but also ductility and hysteretic energy dissipation demands on lateral load resisting elements during earthquake loading. However, the level of reduction strongly depends on the plan-wise distribution of supplemental damping. Nearly optimal reduction in demands on the outermost flexible-side element, an element generally considered to be the most critical element, was realized when damping was distributed unevenly in the system plan such …

Direct Displacement-Based Design Using Inelastic Design Spectrum, Rakesh K. Goel, Anil K. Chopra

Civil and Environmental Engineering

No abstract provided.

Thermally Treated Coal Tar Contaminated Soil As A Concrete Aggregate, Katherine E. Leblanc, John L. Durant, Christopher Swan, Michael J. Weaver, Daniel C. Jansen

Civil and Environmental Engineering

The current practice of landfilling thermally treated and untreated coal tar-contaminated soil is expensive, and it is a waste of a potentially useful material and landfill space. A less expensive and possibly more practical alternative is to use coal tar-contaminated soil as an aggregate in concrete. Because little work has been done in this area, the present study was undertaken to evaluate the effects of coal tar-contamination and thermal treatment on the physical properties of soil and the strength of concrete containing contaminated soil as an aggregate. Also assessed was the leachability of coal tar constituents (specifically, polycyclic aromatic hydrocarbons …

Field Case Histories For Spt-Based In Situ Liquefaction Potential Evaluation, K. Onder Cetin, Raymond B. Seed, Robb E.S. Moss, Armen Der Kiureghian, Kohji Tokimatsu, Leslie F. Harder, Jr., Robert E. Kayen

Civil and Environmental Engineering

This report provides documentation of the field performance case histories and site response analyses described in the report entitled "SPT-Based Probabilistic and Deterministic Assessment of Seismic Soil Liquefaction Initiation Hazard," by Cetin, et al. (2000).

Table 3-5, taken from that report, summarizes the interpreted field performance case histories from the original database of Seed et al. (1984) that were found to conform to the standards of Data Classes A, B or C, and so were used in the studies of Cetin et al. Table 3-7, also taken from that report, summarizes the cases that were deleted from the overall database …

Wavelet-Based Approach For Structural Damage Detection, Z. Hou, Mohammad N. Noori, R. St. Amand

Office of the Dean (CENG) Scholarship

A wavelet-based approach is proposed for structural damage detection and health monitoring. Characteristics of representative vibration signals under the wavelet transformation are examined. The methodology is then applied to simulation data generated from a simple structural model subjected to a harmonic excitation. The model consists of multiple breakable springs, some of which may suffer irreversible damage when the response exceeds a threshold value or the number of cycles of motion is accumulated beyond their fatigue life. In cases of either abrupt or accumulative damages, occurrence of damage and the moment when it occurs can be clearly determined in the details …

Supplemental Viscous Damping Effects On Seismic Demands Of Linear Elastic Systems, Linda M. Tam, Rakesh K. Goel

Civil and Environmental Engineering

The objective of this study is to examine the effects of viscous supplemental damping on response quantities of asymmetric-plan structures responding in a linearly elastic fashion. The response quantities which will be investigated include: element deformations, base shears, and base torques. These response quantities will be normalized, evaluated, and then analyzed.

It is shown that supplemental damping is indeed effective in reducing element deformations and base torques. In some cases, supplemental damping is also effective in reducing base shears. In order to achieve the largest reduction in flexible element deformation, it is recommended that all fluid viscous dampers be placed …

Desiccation And Cracking Behavior Of Three Compacted Landfill Liner Soils, N. Yesiller, C. J. Miller, G. Inci, K. Yaldo

Civil and Environmental Engineering

Tests were conducted to investigate desiccation cracking of three compacted liner soils obtained from local landfills in southeast Michigan. The soils had low plasticity with varying fines content. Large-scale samples of the soils were subjected to wetting and drying cycles. Surficial dimensions of cracks and suction in the soils were monitored. Surficial dimensions of cracks were quantified using the crack intensity factor (CIF), which is the ratio of the surface area of cracks to the total surface area of a soil. All of the soils were subjected to a compaction–dry cycle (i.e. soils were allowed to dry after compaction) and …

Modified Testing Procedure For The Two Parameter Fracture Model For Concrete, Daniel C. Jansen, W. Jason Weiss, Stefan H.F. Schleuchardt

Civil and Environmental Engineering

No abstract provided.

Control Of Earthquake Induced Vibrations In Asymmetric Buildings Using Passive Damping, Rakesh K. Goel

Civil and Environmental Engineering

This paper summarizes the results of a recent investigation on the dynamic response of asymmetric-plan buildings with supplemental viscous damping to harmonic ground motion using modal analysis techniques. It is shown that most modal parameters, except modal damping ratios and dynamic amplification factors, are affected very little by the plan-wise distribution of supplemental damping in the practical range of system parameters. The first modal damping ratio increases while the second decreases as CSD moves from right to left of the system plan, and their values increase with larger plan-wise spread of the supplemental damping. Trends for the dynamic amplification factors …

Application Of Inelastic Design Spectrum To Capacity-Demand Diagram Methods, Anil K. Chopra, Rakesh K. Goel

Civil and Environmental Engineering

An improved capacity-demand-diagram method that uses the well-known constant-ductility design spectrum for the demand diagram is developed and illustrated by examples. This method estimates the deformation of inelastic SDF systems consistent with the selected inelastic design spectrum, while retaining the attraction of graphical implementation of the ATC-40 Nonlinear Static Procedure.

Evaluation Of Nsp To Estimate Seismic Deformation: Sdf Systems, Anil K. Chopra, Rakesh K. Goel

Civil and Environmental Engineering

Investigated in this paper is the approximation in the ATC-40 nonlinear static procedure (NSP) that the earthquake-induced deformation of an inelastic single-degree-of-freedom (SDF) system can be estimated by an iterative method requiring analysis of a sequence of equivalent linear systems. Several deficiencies in the ATC-40 Procedure A are demonstrated. This iterative procedure did not converge for some of the systems analyzed. It converged in many cases, but to a deformation much different than dynamic (nonlinear response history or inelastic design spectrum) analysis of the inelastic system. The ATC-40 Procedure B always gives a unique value of deformation, same as that …

Seismic Behaviour Of Asymmetric Buildings With Supplemental Damping, Rakesh K. Goel

Civil and Environmental Engineering

This paper investigates the response of asymmetric‐plan buildings with supplemental viscous damping to harmonic ground motion using modal analysis techniques. It is shown that most modal parameters, except dynamic amplification factors (DAFs), are affected very little by the plan‐wise distribution of supplemental damping in the practical range of system parameters. Plan‐wise distribution of supplemental damping significantly influences the DAFs, which, in turn, influence the modal deformations. These trends are directly related to the apparent modal damping ratios; the first modal damping ratio increases while the second decreases as CSD moves from right to left of the system plan, and their …

Adsorption Of Pb And Cd Onto Metal Oxides And Organic Material In Natural Surface Coatings As Determined By Selective Extractions: New Evidence For The Importance Of Mn And Fe Oxides, Deming Dong, Yarrow M. Nelson, Leonard W. Lion, Michael L. Shuler, Whilliam C. Ghiorse

Civil and Environmental Engineering

Surface coatings (biofilms and associated minerals) were collected on glass slides in the toxic surface waters of Cayuga Lake (New York State, U.S.A.) and were used to evaluate the relative contributions of Fe, Mn and Al oxides and organic material to total observed Pb and Cd adsorption by the surface coating materials. Several alternative selective extraction techniques were evaluated with respect to both selectivity and alteration of the residual unextracted material. Pb and Cd adsorption was measured under controlled laboratory conditions (mineral salts solution with defined metal speciation, ionic strength 0.05 M, 25°C and pH 6.0) before and after extractions …

Ultrasonic Testing For Compacted Clayey Soils, Nazli Yesiller, Gokhan Inci, Carol J. Miller

Civil and Environmental Engineering

In this study, tests were conducted to investigate the use of ultrasonic methods to determine compaction characteristics of clayey soils. In particular, through-transmission test method was used to determine P-wave velocities in compacted clayey soils. Effects of soil type and compaction conditions on velocity were investigated. Tests were conducted on three soils that had low, medium, and high plasticity. Soils were prepared at water contents ranging from dry to wet of optimum using standard and modified compaction efforts. It was observed that velocity increased with increasing compactive effort and decreasing plasticity and clay content. Moreover, the variation of ultrasonic velocity …

Thermal Properties Of High Water Content Materials, James L. Hanson, Tuncer B. Edil, Nazli Yesiller

Civil and Environmental Engineering

Fundamental thermal properties of various high water content materials were determined using a number of thermal testing methods. Tests were conducted on peat soils, solid wastes, industrial sludge, and bentonite slurries. Thermal conductivity, heat capacity, and thermal diffusivity were determined. The thermal conductivity of the materials was determined using a needle probe method. The volumetric heat capacity of the materials was determined using a dual probe method. These values were used together to obtain thermal diffusivity. Analytical methods are also used to determine heat capacity and thermal diffusivity. The theory for determination of thermal parameters using the various methods is …

Unsaturated Performance Comparison Of Compacted Clay Landfill Liners, Carol J. Miller, Saad Merayyan, Nazli Yesiller

Civil and Environmental Engineering

Tests were conducted to determine the variation in volumetric water content and pore water suction for a variety of compacted clay soils used in the construction of landfill liners. The fit of the experimental data to an existing parametric model was investigated for two different fitting techniques. The first technique involves the use of the retention curve computer program (RETC) developed for the U.S. EPA. The second technique employs the Solver subroutine included in Microsoft Excel. The parametric models resulting from either technique correlated well to the experimental data. However, the individual curve fit parameters varied significantly. The effect of …

Random Vibration Studies Of An Sdof System With Shape Memory Restoring Force, L. Duval, Mohammad N. Noori, Z. Hou, H. Davoodi, S. Seelecke

Office of the Dean (CENG) Scholarship

Intelligent and adaptive material systems and structures have become very important in engineering applications. The basic characteristic of these systems is the ability to adapt to the environmental conditions. A new class of materials with promising applications in structural and mechanical systems is shape memory alloy (SMA). The mechanical behavior of shape memory alloys in particular shows a strong dependence on temperature. This property provides opportunities for the utilization of SMAs in actuators or energy dissipation devices. However, the behavior of systems containing shape memory components under random excitation has not yet been addressed in the literature. Such a study …

Capacity‐Demand‐Diagram Methods Based On Inelastic Design Spectrum, Anil K. Chopra, Rakesh K. Goel

Civil and Environmental Engineering

An improved capacity‐demand‐diagram method that uses the well‐known constant‐ductility design spectrum for the demand diagram is developed and illustrated by examples. This method estimates the deformation of inelastic SDF systems consistent with the selected inelastic design spectrum, while retaining the attraction of graphical implementation of the ATC‐40 Nonlinear Static Procedure. One version of the improved method is graphically similar to ATC‐40 Procedure A whereas the second version is graphically similar to ATC‐40 Procedure B. However, the improved procedures differ from ATC‐40 procedures in one important sense. The demand diagram used is different: the constant‐ductility demand diagram for inelastic systems …

Lead Binding To Metal Oxide And Organic Phases Of Natural Aquatic Biofilms, Yarrow M. Nelson, Leonard W. Lion, Michael L. Shuler, William C. Ghiorse

Civil and Environmental Engineering

The role of the composition of surface-coating materials in controlling trace metal adsorption in aquatic environments was investigated using natural biofilms that developed on glass slides in three New York State lakes and a water-supply well. Adsorption isotherms were obtained for Pb binding to each of the biofilms in solutions with defined Pb speciation at 25°C and pH 6.0, with Pb concentrations ranging from 0.2 to 2.0 μM. Adsorption isotherms for Pb binding to laboratory-derived metal oxides and surrogate organic materials were determined under the same conditions. These isotherms, combined with characterization of natural biofilm composition, were used to estimate …

Closure To Period Formulas For Concrete Shear Wall Buildings, Anil K. Chopra, Rakesh K. Goel

Civil and Environmental Engineering

No abstract provided.

Environmental Applications Of Gps, Samuel A. Vigil, Dora Zueck

Civil and Environmental Engineering

The use of the Global Positioning System (GPS) has revolutionized air travel, ocean navigation, land navigation, and the collection of environmental data. Although a basic civilian GPS receiver can be purchased for as little as $100, the receiver is only the tip of a 12 billion dollar iceberg! This paper will discuss the history and basic operation of the Global Positioning System, a satellite-based precision positioning and timing service developed and operated by the Department of Defense. It will also describe the accuracy limitations of the civil GPS service and how accuracy can be enhanced by the use of differential …

Application Of Noise Control In Environmental Engineering Education, Harold M. Cota, Kristy Grace

Civil and Environmental Engineering

Noise control is both a factor in the health and safety of those in the workplace and in the annoyance and interference of the quality of life at home. This falls squarely in the realm of the Environmental Engineering Profession. Noise, its effects and control, is an important element of a few Graduate Environmental Engineering Programs, but it does not have a role in most undergraduate programs. One objective of this paper is to demonstrate that noise is an issue needing to be addressed in Environmental Engineering Programs and to suggest that making it a requirement at the undergraduate level …

Early Experimentation With Civil Engineering Materials, James L. Hanson

Civil and Environmental Engineering

A new project-based teaching method emphasizing laboratory experimentation is being used at Lawrence Technological University. It has excited and energized the students about civil engineering applications. Engineering concepts are introduced early in the students’ academic careers using civil engineering materials. Laboratory activities related to a Civil Engineering Materials course are being used for outreach, recruitment, and an intensive laboratory experience. A departmental effort has included supporting an outreach program and expanding a freshman CE Materials course. This new teaching method has affected and complemented university recruitment and retention efforts. The course introduces incoming students to engineering analysis and the basic …

Possible Explanations Of Phase Transitions In Highway Traffic, C.F. Daganzo, M.J. Cassidy, Robert L. Bertini

Civil and Environmental Engineering

It is shown that all the phase transitions in and out of freely flowing traffic reported earlier for a German site could be caused by bottlenecks, as are all the transitions observed at two other sites examined here. The evidence suggests that bottlenecks cause these transitions in a predictable way, and does not suggest that stoppages (jams) appear spontaneously in free flow traffic for no apparent reason. It is also shown that many of the complicated instability phenomena observed at all locations can be explained qualitatively in terms of a simple Markovian theory specific to traffic that does not necessarily …

Seismic Control Of Asymmetric Structures, Rakesh K. Goel

Civil and Environmental Engineering

No abstract provided.

Capacity-Demand-Diagram Methods For Estimating Seismic Deformation Of Inelastic Structures: Sdf Systems, Anil K. Chopra, Rakesh K. Goel

Civil and Environmental Engineering

The ATC-40 and FEMA-274 documents contain simplified nonlinear analysis procedures to determine the displacement demand imposed on a building expected to deform inelastically. The Nonlinear Static Procedure in these documents, based on the capacity spectrum method, involves several approximations: The lateral force distribution for pushover analysis and conversion of these results to the capacity diagram are based only on the fundamental vibration mode of the elastic system. The earthquake-induced deformation of an inelastic SDF system is estimated by an iterative method requiring analysis of a sequence of equivalent linear systems, thus avoiding the dynamic analysis of the inelastic SDF system. …

Capacity-Demand-Diagram Methods For Estimating Seismic Deformation Of Inelastic Structures: Sdf Systems, Anil K. Chopra, Rakesh K. Goel

Civil and Environmental Engineering

The ATC-40 and FEMA-274 documents contain simplified nonlinear analysis procedures to determine the displacement demand imposed on a building expected to deform inelastically. The Nonlinear Static Procedure in these documents, based on the capacity spectrum method, involves several approximations: The lateral force distribution for pushover analysis and conversion of these results to the capacity diagram are based only on the fundamental vibration mode of the elastic system. The earthquake-induced deformation of an inelastic SDF system is estimated by an iterative method requiring analysis of a sequence of equivalent linear systems, thus avoiding the dynamic analysis of the inelastic SDF system. …