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Full-Text Articles in Engineering
Preliminary Report On December 22, 2003 San Simeon Earthquake, Rakesh K. Goel
Preliminary Report On December 22, 2003 San Simeon Earthquake, Rakesh K. Goel
Civil and Environmental Engineering
A strong earthquake of magnitude 6.5 ( Mw) struck the Central Coast of California at 11:15:56 AM PST (19:15:56 UTC) on Monday, December 22, 2003. The epicenter (Figure 1) was 11 km (7 mile) NE of San Simeon, at a depth of about 8 km (5 mile). Two people were killed and about 40 buildings collapsed or severely damaged at Paso Robles which is located about 39 km (24 mile) from the epicenter. At least 40 people were reported to be injured in the Paso Robles-Templeton area. This preliminary report presents basic information on the epicenter location, intensity …
Evaluation Of Nonlinear Static Procedures Using Strong-Motion Records Of Buildings, Rakesh K. Goel
Evaluation Of Nonlinear Static Procedures Using Strong-Motion Records Of Buildings, Rakesh K. Goel
Civil and Environmental Engineering
The objective of this investigation is to evaluate the FEMA-356 Nonlinear Static Procedure (NSP) and a recently developed Modal Pushover Analysis (MPA) procedure using recorded motions of four buildings that were damaged during the 1994 Northridge earthquake. For this purpose, the motions at non-instrumented floors are “derived” from the motions at instrumented floors by using cubic spline interpolation procedure. Analytical models of the four buildings are developed using the computer program D2DX and calibrated by matching the computed vibration periods and the “elastic” periods identified form the recorded motions. Accuracy of the computer model is evaluated by comparing the computed …
A Modal Pushover Analysis Procedure To Estimate Seismic Demands For Unsymmetric-Plan Buildings: Theory And Preliminary Evaluation, Anil K. Chopra, Rakesh K. Goel
A Modal Pushover Analysis Procedure To Estimate Seismic Demands For Unsymmetric-Plan Buildings: Theory And Preliminary Evaluation, Anil K. Chopra, Rakesh K. Goel
Civil and Environmental Engineering
Based on structural dynamics theory, the modal pushover analysis procedure (MPA) retains the conceptual simplicity of current procedures with invariant force distribution, now common in structural engineering practice. The MPA procedure for estimating seismic demands is extended to unsymmetric-plan buildings. In the MPA procedure, the seismic demand due to individual terms in the modal expansion of the effective earthquake forces is determined by nonlinear static analysis using the inertia force distribution for each mode, which for unsymmetric buildings includes two lateral forces and torque at each floor level. These “modal” demands due to the first few terms of the modal …
A Multiobjective Sdss For Management Of Urbanizing Watersheds: The Case Of The Lower Kaskaskia Basin, Illinois, Kyle O. Allred, John W. Nicklow, Misgana K. Muleta, Leslie A. Duram
A Multiobjective Sdss For Management Of Urbanizing Watersheds: The Case Of The Lower Kaskaskia Basin, Illinois, Kyle O. Allred, John W. Nicklow, Misgana K. Muleta, Leslie A. Duram
Civil and Environmental Engineering
The conversion of natural and agriculturally dominated watersheds to industrial, commercial and residential developments leads to a cascade of adjustments in runoff quantity and stream quality at locations further downstream. The use of sophisticated hydrologic simulation models and Geographic Information Systems (GIS) has become the standard for evaluating these impacts of urban sprawl on water resources systems. Simulation and GIS models alone, however, are incapable of directly revealing optimal land development patterns that meet specified objectives. This paper describes the development of a multi-objective Spatial Decision Support System (SDSS) designed to overcome this limitation. The SDSS is created by integrating …
Engineering The World: Hands-On Experimentation For Civil Engineering K-12 Outreach, James L. Hanson, Donald D. Carpenter, Tarek Rizk
Engineering The World: Hands-On Experimentation For Civil Engineering K-12 Outreach, James L. Hanson, Donald D. Carpenter, Tarek Rizk
Civil and Environmental Engineering
This paper details the development and application of a community outreach program designed to teach children about math, science, and the world in which they live. The program was titled “Engineering the World” and emphasized civil engineering applications. The program was offered in an inner-city middle school in Detroit, Michigan. The program was developed by civil engineering professors at Lawrence Technological University with the assistance of undergraduate engineering students. The activities were categorized by civil engineering discipline including construction, environmental, geotechnical, hydraulics, structural, surveying, and transportation. The paper describes details of several of the hands-on experiments and provides an assessment …
Phytostimulation Of Hydrocarbon Biodegradation By Arroyo Willows In Laboratory Microcosms, Kenneth M. Hoffman, Yarrow M. Nelson
Phytostimulation Of Hydrocarbon Biodegradation By Arroyo Willows In Laboratory Microcosms, Kenneth M. Hoffman, Yarrow M. Nelson
Civil and Environmental Engineering
Controlled laboratory microcosms with and without Arroyo Willows (Salix lasiolepis) were used to elucidate potential mechanisms of phytoremediation of hydrocarbon-contaminated groundwater at a contaminated oil field near Guadalupe, CA. Laboratory control allows us to examine the synergistic effects between the plants themselves and the rhizobial bacteria associated with them. Laboratory microcosms were set up in triplicate with (1) sodium azide-inhibited soil, (2) soil with active bacteria, and (3) soil with active bacteria and willows. Hydrocarbon-contaminated groundwater was recirculated through the root zone for 105 days. Biodegradation rates were estimated by measuring total petroleum hydrocarbon (TPH) concentration and monitoring chemical oxygen …
Optimization Of High-Strength Hydrocarbon Biodegradation Using Respirometry, Bunkim G. Chokshi, Yarrow M. Nelson
Optimization Of High-Strength Hydrocarbon Biodegradation Using Respirometry, Bunkim G. Chokshi, Yarrow M. Nelson
Civil and Environmental Engineering
Laboratory respirometry experiments were conducted on mixtures of soil and oily sludge to estimate biodegradation rates by CO2 production rates and determine optimum conditions for biodegradation of high-strength hydrocarbon waste products. These experiments were used to determine a suitable range of total petroleum hydrocarbon (TPH) concentration for biological treatment and to optimize for nutrient addition and moisture content. CO2 production rates from biological respiration of hydrocarbon-contaminated soil were maximized at concentrations of 3-9% TPH (30,00090,000 mg/kg TPH). CO2 production rates decreased dramatically at concentrations above 9% TPH, indicating that either these concentrations are lethal to microbes present, …
Experimental Investigation Of Dynamic Response Of Compacted Clayey Soils, Gokhan Inci, Nazli Yesiller, Takaaki Kagawa
Experimental Investigation Of Dynamic Response Of Compacted Clayey Soils, Gokhan Inci, Nazli Yesiller, Takaaki Kagawa
Civil and Environmental Engineering
A study was conducted to determine the dynamic properties of compacted clayey soils subjected to low amplitude vibration. A fast and simple ultrasonic pulse transmission method was used. Tests were conducted on three clayey soils with low to high plasticity compacted using standard and modified Proctor effort over a range of water contents. The samples were allowed to dry after compaction and P-wave velocity, S-wave velocity, Poisson's ratio, and shear modulus were determined. The effects of soil type, compaction conditions, and degree of saturation on the dynamic response of the soils were investigated. The elastic wave velocities and the dynamic …
Evaluation Of Nonlinear Static Procedures Using Strong-Motion Building Records, Rakesh K. Goel
Evaluation Of Nonlinear Static Procedures Using Strong-Motion Building Records, Rakesh K. Goel
Civil and Environmental Engineering
The objective of this investigation is to evaluate the FEMA-356 Nonlinear Static Procedure (NSP) and a recently developed Modal Pushover Analysis (MPA) procedure using recorded motions of buildings that were damaged during the 1994 Northridge earthquake. It is found the FEMA-356 NSP typically underestimates the drifts in upper stories and overestimates them in lower stories. The MPA procedure provides much-improved estimates of the response compared to the FEMA-356 NSP. In particular, the MPA procedure, unlike the FEMA-356 NSP, is able to capture the effects of higher modes.
Cpt-Based Probabilistic Assessment Of Seismic Soil Liquefaction Initiation., Robb E.S. Moss
Cpt-Based Probabilistic Assessment Of Seismic Soil Liquefaction Initiation., Robb E.S. Moss
Civil and Environmental Engineering
The correlation of seismic field performance with in situ index test results has been proven to be a reliable method for defining the threshold between liquefaction and non-liquefaction. The objective of this research was to define in the most accurate and unbiased manner possible the initiation of seismic soil liquefaction using the Cone Penetration Test (CPT). Case histories of occurrence and non-occurrence of soil liquefaction were collected from seismic events over the past three decades. These were processed to develop improved CPT-based correlations for prediction of the likelihood of “triggering” or initiation of soil liquefaction during earthquakes. Important advances over …
Cpt-Based Liquefaction Field Case Histories From The 1995 Hyogoken-Nambu (Kobe) Earthquake, Japan, Y. Suzuki, Kohji Tokimatsu, Robb E.S. Moss, Raymond B. Seed, Robert E. Kayen
Cpt-Based Liquefaction Field Case Histories From The 1995 Hyogoken-Nambu (Kobe) Earthquake, Japan, Y. Suzuki, Kohji Tokimatsu, Robb E.S. Moss, Raymond B. Seed, Robert E. Kayen
Civil and Environmental Engineering
This report documents CPT-based field case histories from the 1995 Hyogoken-Nambu (Kobe) Earthquake in Japan. These case histories are proprietary and were acquired by Mr. Y. Suzuki of the Kajima Corporation under the supervision of Prof. K. Tokimatsu of Tokyo Institute of Technology. Each case history is composed of two pages, one page of vital statistics and one page showing the CPT trace with the assumed critical layer delineated. Field performance of each site was assessed by Mr. Y. Suzuki as well as the performance assessments published in Akai et al. (1995). The liquefaction and non-liquefaction data that were used …
Recent Advances In Soil Liquefaction Engineering: A Unified And Consistent Framework, Raymond B. Seed, K. Onder Cetin, Robb E.S. Moss, Annie M. Kammerer, Jiaer Wu, Juan M. Pestana, Michael F. Riemer, Rodolfo B. Sancio, Jonathan D. Bray, Robert E. Kayen, Allison Faris
Recent Advances In Soil Liquefaction Engineering: A Unified And Consistent Framework, Raymond B. Seed, K. Onder Cetin, Robb E.S. Moss, Annie M. Kammerer, Jiaer Wu, Juan M. Pestana, Michael F. Riemer, Rodolfo B. Sancio, Jonathan D. Bray, Robert E. Kayen, Allison Faris
Civil and Environmental Engineering
Over the past decade, major advances have occurred in both understanding and practice with regard to assessment and mitigation of hazard associated with seismically induced soil liquefaction. Soil liquefaction engineering has evolved into a sub-field in its own right, and engineering assessment and mitigation of seismic soil liquefaction hazard is increasingly well addressed in both research and practice. This rapid evolution in the treatment of liquefaction has been pushed largely by a confluence of lessons and data provided by a series of major earthquakes over the past dozen years, as well as by the research and professional/political will engendered by …
Statistics Of Single-Degree-Of-Freedom Estimate Of Displacement For Pushover Analysis Of Buildings, Anil K. Chopra, Rakesh K. Goel, Chatpan Chintanapakdee
Statistics Of Single-Degree-Of-Freedom Estimate Of Displacement For Pushover Analysis Of Buildings, Anil K. Chopra, Rakesh K. Goel, Chatpan Chintanapakdee
Civil and Environmental Engineering
Investigated is the basic premise that the roof displacement of a multistory building can be determined from the deformation of a single-degree-of-freedom (SDF) system. The responses of both systems are determined rigorously by nonlinear response history analysis, without introducing any of the approximations underlying the simplified methods for estimating the deformation of a SDF system (see, e.g., FEMA-273 or ATC-40 guidelines). The statistics of the SDF system estimate of roof displacement are presented for a variety of generic frames and six SAC buildings subjected to ground motion ensembles. Data obtained for generic frames indicate that the first ‘‘mode’’ SDF system …
Analysis Of Temperatures At A Municipal Solid Waste Landfill, Nazli Yesiller, James L. Hanson
Analysis Of Temperatures At A Municipal Solid Waste Landfill, Nazli Yesiller, James L. Hanson
Civil and Environmental Engineering
A study is conducted to determine the thermal regime within and around a municipal solid waste landfill located in midwestern U.S.A. Spatial distributions of temperatures have been determined over time since 1999 within the waste mass, liner and cover systems, and surrounding subgrade. Seasonal variations, placement of waste, age of waste, depth and location of waste, and available moisture have significant effects on temperatures. Temperatures of wastes at shallow depths, bottom liner systems prior to waste placement, and final cover systems conform to seasonal temperature variations. Steady elevated temperatures are reached with respect to air and ground temperatures at central …