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A Multicriteria Based Quantitative Framework For Assessing Sustainability Of Pile Foundations, Aditi Misra Dec 2010

A Multicriteria Based Quantitative Framework For Assessing Sustainability Of Pile Foundations, Aditi Misra

Master's Theses

ABSTRACT

Civil Engineering is the major instrument of anthropocentric development over centuries through ever expanding infrastructure, cities and facilities. Civil engineering processes are both resource and fuel intensive. The building industry alone, during the construction stage, uses about 30-40% of the total resources used in the industrialized countries. There is a growing consensus that delivering a sustainable built environment starts with incorporating sustainability thoughts at the planning and design stages of a project. Geotechnical engineering is most resource intensive although this intensive consumption of energy goes unnoticed mainly because of the indirect nature of the energy used in the …


Investigating Wood Welding Parameters Using A Prototype Welding Machine, Timothy R. Melin Dec 2010

Investigating Wood Welding Parameters Using A Prototype Welding Machine, Timothy R. Melin

Master's Theses

Understanding how different processing variables influence wood welded bonds is vital if the technique will ever be used to create engineered lumber without using adhesives. A variation of vibration welding, wood welding uses pressure and friction to bond materials together. During welding, heat causes a softening in the wood, a naturally occurring composite material. This softening leads to fiber entanglement and a bond forms upon cooling.

The goal of this research was to investigate several processing aspects of the wood welding procedure. A prototype wood welding machine, designed and fabricated from the ground up, was used to investigate the effects …


An Investigation Of Initially Delaminated Composite Sandwich With Delamination Arrest Mechanism Under Buckling Loading, Tony D. Tran Dec 2010

An Investigation Of Initially Delaminated Composite Sandwich With Delamination Arrest Mechanism Under Buckling Loading, Tony D. Tran

Master's Theses

This thesis involves the development of a fiberglass-foam composite sandwich structure with the introduction of delamination arrestment keys; therefore, a study of an initially delaminated composite sandwich structure was the experimental analysis on multiple configurations in how the arrestment keys are placed.

The first part of this thesis research was to the experimental design and manufacturing of the composite sandwich plates. These plates were later cut down to the specific test dimensions and manufacturing processes for the composite sandwich plates and test specimens were created. The composite sandwich plates were manufactured using a vacuum resin infusion process. The dimensions of …


Anaerobic Co-Digestion Of Wastewater Treatment Pond Algae With Wastewater Sludge, Daniel Eric Heimel Dec 2010

Anaerobic Co-Digestion Of Wastewater Treatment Pond Algae With Wastewater Sludge, Daniel Eric Heimel

Master's Theses

Microalgae harvested from wastewater treatment ponds can be anaerobically digested to produce biogas, a renewable fuel resource. However, past experiments have shown some limitations of algae digestion. Algal cell walls are thought to be resistant to digestion, and the high protein content of algae can lead to ammonia toxicity in digesters. Co-digestion of algae with substrates containing higher C:N ratios (e.g., waste paper) can be used to maintain non-inhibitory ammonia concentrations and increase methane production. However, high carbon waste co-substrates have become costly or are not readily available in many communities. Although domestic wastewater sludge has only a marginally higher …


An Investigation Of The Influence Of Diaphragm Flexibility On Building Design Through A Comparison Of Forced Vibration Testing And Computational Analysis, Blake Alan Roskelley Nov 2010

An Investigation Of The Influence Of Diaphragm Flexibility On Building Design Through A Comparison Of Forced Vibration Testing And Computational Analysis, Blake Alan Roskelley

Master's Theses

An assessment of the validity of idealizing a concrete diaphragm as rigid was performed through the modal analysis of three existing buildings. Modal analysis was performed both by physical experimentation and computational analysis. Experimental determination of the mode shapes shows that two of the three buildings’ diaphragms exhibited flexible behavior. The experimental results were compared to computational analysis results and were shown to be similar, confirming that that the two building diaphragms are not rigid. As a standard, diaphragms with aspect ratios less than three are permitted to be idealized as rigid per ASCE 7-05. To determine the effect of …


Traffic Safety Investigations For Local Agencies, Jacob D. Hudson Oct 2010

Traffic Safety Investigations For Local Agencies, Jacob D. Hudson

Master's Theses

National and statewide (California) collision numbers are currently on the

decline; however, the U.S. is declining at a much slower rate than most other

developed countries, and in some aspects is actually regressing in terms of traffic

safety. Although state highway safety is improving, local roadway safety may

actually be regressing. Approximately three-quarters of all U.S. public roadways,

and approximately 80% of all injury accidents fall under the jurisdiction of cities.

However, cities may not be allocating the proper level of resources, or operating

under the proper administrative methodologies to adequately address these

safety issues.

This research finds that on …


Performance-Based Analysis Of Steel Buildings: Special Concentric Braced Frame, Scott Michael Adams Sep 2010

Performance-Based Analysis Of Steel Buildings: Special Concentric Braced Frame, Scott Michael Adams

Master's Theses

The performance-based analysis methods and evaluation criteria in ASCE 41-06 were used to evaluate a special concentric braced frame building based on the design standards in ASCE 7-05. A rectangular, six-story office building was evaluated using linear static, linear dynamic, nonlinear static, and nonlinear dynamic procedures. The results showed that the linear procedures underestimated damage compared to the nonlinear procedures, with the building performing to Life Safety for the linear procedures, and the nonlinear procedures indicating component damage beyond the intended Life Safety limit for the 2/3 maximum considered earthquake (MCE) hazard. This trend continued to the maximum considered earthquake …


Scale Model Shake Table Testing Of Underground Structures In Soft Clay, Victor A. Crosariol Jun 2010

Scale Model Shake Table Testing Of Underground Structures In Soft Clay, Victor A. Crosariol

Master's Theses

Underground structures perform an important role in transportation systems in many seismically active regions around the world, but empirical data regarding the seismic behavior of these structures is limited. This research works towards filling that empirical gap through the use of scale model shake table testing. Underground seismic soil-structure interaction (USSSI) effects were investigated for a stiff rectangular tunnel cross-section embedded within soft clay. San Francisco Young Bay Mud was used as a prototype soil for developing a scale model soil mixture consisting of kaolinite, bentonite, class C fly ash, and water. A single cell Bay Area Rapid Transit (BART) …


Performance Of A Stormwater Filter And Bacteria Inactivation Using Biocidal Media, Alexander Scott Bowerman Mar 2010

Performance Of A Stormwater Filter And Bacteria Inactivation Using Biocidal Media, Alexander Scott Bowerman

Master's Theses

There are many possible ways to mitigate stormwater pollution, but this study focused on the DrainPacTM catchment basin insert and the feasibility of integrating N-halamine biocidal brominated beads into the filter system. This study was divided into three sections. The first section involved testing a DrainPacTM filter for treatable flow rates, head loss, and removal of solids, oil, and bacteria. The DrainPacTM filter is designed to be installed in a stormwater catch basin. The filter is composed of a 12 x 41 inch metal frame with textile filter media attached to it in a basket shape. The upper portion of …


City Of Davis Greenbelt Master Plan, Brandon Haydu Mar 2010

City Of Davis Greenbelt Master Plan, Brandon Haydu

Master's Theses

The City of Davis is currently updating its Parks and Recreation Facilities Master Plan. During the update, greenbelts were identified as a highly used and desired facility. This Greenbelt Master Plan serves as a plan focused on the opportunities greenbelts can provide as recreational and transportation facilities. This report has analyzed community feedback, greenbelt coverage, greenbelt capacity, and existing local, state, and federal design guidelines. The final plan is a set of goals, objectives, policies, and programs, along with a greenbelt map, which is aimed at improving the greenbelt infrastructure in Davis through the year 2020.


Influence Of Material Type, Aggregate Size, And Unconfined Compressive Strength On Water Jetting Of Cidh Pile Anomalies, Joseph Carl Heavin Mar 2010

Influence Of Material Type, Aggregate Size, And Unconfined Compressive Strength On Water Jetting Of Cidh Pile Anomalies, Joseph Carl Heavin

Master's Theses

Water jetting as a means for removing anomalous materials from cast-in-drilled-hole (CIDH) piles was examined. The primary objective of this research was to establish empirical relationships between different jetting parameters and the removal of commonly occurring anomalous zone materials, including low-strength concrete, slurry mixed concrete, grout, and clay soil. Also investigated was the current standard-of-practice used by water jetting contractors within California. The testing specimens consisted of typical anomalous material with unconfined compressive strengths between 5 and 6,000 psi. The experimental work consisted of water blasting submerged specimens using rotary jets, nozzles, and pumping equipment typically used in construction practice. …


Identification Of Physical Changes To A Steel Frame, Daniel Eric Means Feb 2010

Identification Of Physical Changes To A Steel Frame, Daniel Eric Means

Master's Theses

The thesis utilized physical testing and computer modeling to determine the feasibility of identifying a change to the mass or stiffness of a steel frame. Physical testing was performed using an accelerometer, linear shaker, and arbitrary function generator. Two methods of laboratory testing were developed: ambient vibration testing (AVT) and forced vibration testing (FVT). AVT was able to preliminarily identify the natural frequencies and mode shapes of the frame. FVT was able to precisely identify four distinct natural frequencies, mode shapes, and damping ratios. The baseline frame then underwent two physical changes: the addition of mass to its roof, and …