Civil and Environmental Engineering Commons^™

Extending Time Series Forecasting Methods Using Functional Principal Components Analysis, Isaac Michael Wagner-Muns

Masters Theses

"Traffic volume forecasts are used by many transportation analysis and management systems to better characterize and react to fluctuating traffic patterns. Most current forecasting methods do not take advantage of the underlying functional characteristics of the time series to make predictions. This paper presents a methodology that uses Functional Principal Components Analysis (FPCA) to create smooth and differentiable daily traffic forecasts. The methodology is validated with a data set of 1,813 days of 15 minute aggregated traffic volume time series. Both the FPCA based forecasts and the associated prediction intervals outperform traditional Seasonal Autoregressive Integrated Moving Average (SARIMA) based methods"--Abstract, …

Assessment Of Rockfall Rollout Risk Along Varying Slope Geometries Using The Rocfall And Crsp Software, Mariam S. Al E'Bayat

Masters Theses

"Most routes in mountainous areas suffer from rock falling, rolling and bouncing risk. There are many computer programs concerned with simulating the rockfall problem, and whereas they have the same purpose, they however differ in the input data that's needed to simulate the problem, and they also differ in the way of processing and kind of output.

This study used Rocfall® and the Colorado Rockfall Simulation Program (CRSP®) to simulate sixty-three models of varying slope geometry, where only the slope geometry is changed with the same material properties for both the slope and the rocks.

Both programs were fast and …

Advanced Buffer Materials For Indoor Air Co₂ Control In Commercial Buildings, Pavithra Ethi Rajan

Masters Theses

"The following describes a novel passive approach to control the indoor CO₂ levels in enclosed spaces, primarily focusing on commercial buildings. Amine impregnated silica sorbents were identified as suitable candidates and synthesized; the amine loading ratio was varied to create a range of materials. These samples along with other commercial zeolite candidates have been tested over a range of CO₂ concentrations to determine the CO₂ adsorption capacity in laboratory systems and under simulated room conditions. The research work also focuses on the CO₂ desorption capacity of the candidate adsorbents. The desorption is allowed to occur gradually …

The Use Of Ceramic Water Filters Under Pressure In An In-Line Water Pumping System, Travis Dean Gardner

Masters Theses

"Ceramic pot filters (CPFs) have proven an effective point of use (POU) filter due to their relative low cost, ease to manufacture, and effectiveness at treating contaminated water. These filters are used by individual homes, and sometimes multiple filters are needed for each home in order to produce enough water for the family's household. If these filters could be used in-line with a pumping system or elevated storage tank, water could be filtered and used on demand for a community in an economically feasible way. However, CPFs are too fragile to use under pressure due to the weak points where …

Cloth-Air Partitioning Of Oxybenzone, Jonathan T. Hill

Masters Theses

"Clothing has been proven to be a significant accumulator of chemicals from the air. Semi-volatile organic compounds (SVOCs) have a high affinity towards textiles, and measuring the equilibrium partition coefficient between cloth and air (K_cloth-air) for SVOCs is crucial in predicting human exposure to these compounds. This study aims to quantify K_cloth-air for oxybenzone to contribute to a larger human exposure experiment carried out at the Technical University of Denmark (DTU). K_cloth-air for oxybenzone was calculated using data collected from the exposure chamber at DTU and from performing extractions of oxybenzone in fabric samples from the …

Vegetation Based Assessment And Monitoring Tools For Landfill Leachate Treatment And Fugitive Plumes, Rahul Sukharia

Masters Theses

"Solid waste and leachate generation from solid waste landfills has a legacy of detrimental and toxic impacts on the environment. Disposal practices are expensive, failure prone and have not been able to keep up with the pace of disposal of toxic compounds. In general, a landfill acts as a "bathtub" with infiltration of water through the landfill cover into the landfill, reacting with the waste and transferring toxic components into the leachate. Irrigating the evapotranspiration (ET) covers with leachate collected from the landfill has been developed and applied. Such methods can keep the leached pollutants in a loop, which reduces …

Imaging In Karst Terrain Using The Electrical Resistivity And Multichannel Analyses Of Surface Wave Methods, Ragab W. Jaafar

Masters Theses

"Electrical resistivity tomography and multi-channel analyses of surface waves data were acquired at a study area in Phelps County in the south-central part of Missouri. The objectives of the investigation were fourfold: 1) to image the subsurface in the study area to a depth of 70 feet; 2) to compare the ERT images generated using both the dipole-dipole and Wenner-Schlumberger arrays; and 3) to assess how variations in the MASW array configuration affected MASW data quality; and 4) to compare the ERT-estimated depth to top-of-rock and the MASW-generated depth to top-of-rock.

The subsurface in the study area was imaged to …

Developing Restoration Schemes For A Road Transportation Network In The Event Of A Disaster, Ebin Antony

Masters Theses

"Transportation systems such as rail, road, and waterways are key component of critical infrastructure systems, providing connectivity between other components to enable the production and distribution of goods and services. During large scale disasters such as earth quakes and floods, this connectivity is disrupted, restricting or completely halting the flow of goods and services. To ensure that the connectivity between the different modes of transportation are restored in an aftermath of these disruptions, the interdependence between them and the importance of individual elements to the overall connectivity have to be studied and formulated to develop a system-level restoration plan. This …

Bioaccessibility Of Lead From Lead-Contaminated Soil Upon Phosphate Amendment Using A Physiologically-Based Extraction Test, Samantha Jo Dicenso

Masters Theses

"Lead is known to cause health problems in humans, especially children, and an effective in‐situ remediation option has been sought for years. Adding phosphoric acid (PA) to contaminated soil causes a reaction that binds the lead to phosphate to produce pyromorphite (Pb₅(PO₄)₃Cl), a form of lead believed to be non‐bioavailable; however, field trials have given varied results (Bosso et al 2008; Munksgaard and Lottermoser 2011; Tang et al. 2009). One explanation for these results might be the impact of the agent used to raise pH after phosphoric acid addition. In order to examine this explanation soil was collected from the …

Characterization And Performance Of Eco And Crack-Free High-Performance Concrete For Sustainable Infrastructure, Iman Mehdipour

Doctoral Dissertations

"The main objective of this study is to develop, characterize, and validate the performance of a new class of environmentally friendly, economical, and crack-free high-performance concrete referred to as Eco and crack-free HPC that is proportioned with high content of recycle materials. Two classes of Eco-HPC are designed for: (I) pavement (Eco-Pave-Crete); and (II) bridge infrastructure (Eco-Bridge-Crete). Eco-HPC mixtures were designed to have relatively low binder content up to 350 kg/m³ and develop high resistance to shrinkage and superior durability. A stepwise mixture design methodology was proposed to: (i) optimize binder system and aggregate skeleton to optimize packing density …

Design And Performance Of Cost-Effective Ultra-High Performance Concrete For Prefabricated Elements, Weina Meng

Doctoral Dissertations

"This study presented in this thesis aims to: (1) develop a mixture design methodology for cost-effective ultra-high-performance concrete (UHPC) incorporating high volume of supplementary cementitious materials and conventional concrete and masonry sands; (2) developed UHPC with adapted rheology incorporating lightweight sand, hybrid fibers, and nanomaterials with improved properties; (3) design prefabricated UHPC panels with fiber-reinforced polymers (FRP) for enhanced flexural properties of stay-in-place panels made with optimized UHPC; and (4) explore potential applications of such UHPC elements. The proposed design methodology produced UHPC mixtures with 28-days compressive strengths higher than 125 and 168 MPa under standard water curing and 1-d …

Phytoforensics: Applications In Vapor Intrusion Assessment, Jordan Lee Wilson

Doctoral Dissertations

"Vapor intrusion (VI) occurs when contaminants in the vapor phase migrate in the shallow subsurface and enter buildings through cracks, seams, and gaps and has been recognized as a serious human-health threat as occupants are exposed to potentially harmful concentrations over long periods of time. The VI pathway has recently (2017) been identified as a primary exposure pathway and implemented into the Hazard Ranking System for inclusion on the Nation Priorities List. However, assessing VI and human exposure is not simple and current methods are time-, cost-, and labor-intensive; intrusive; and temporally and spatially variability. Trees are ideal candidates for …

Test Standard For Determining The Fastener-Sheathing Local Translational Stiffness Of Sheathed Cold-Formed Steel Assemblies, 2017 Edition, American Iron And Steel Institute

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

No abstract provided.

Test Standard For Determining The Fastener-Sheathing Rotational Stiffness Of Sheathed Cold-Formed Steel Assemblies, 2017 Edition, American Iron And Steel Institute

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

No abstract provided.

Dermal Uptake Directly From Air Under Transient Conditions: Advances In Modeling And Comparisons With Experimental Results For Human Subjects, G. C. Morrison, C. J. Weschler, G. Bekö

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

To better understand the dermal exposure pathway, we enhance an existing mechanistic model of transdermal uptake by including skin surface lipids (SSL) and consider the impact of clothing. Addition of SSL increases the overall resistance to uptake of SVOCs from air but also allows for rapid transfer of SVOCs to sinks like clothing or clean air. We test the model by simulating di-ethyl phthalate (DEP) and di-n-butyl phthalate (DnBP) exposures of six bare-skinned (Weschler et al. 2015, Environ. Health Perspect., 123, 928) and one clothed participant (Morrison et al. 2016, J. Expo. Sci. Environ. Epidemiol., 26, 113). The model predicts …

Shear Wave Velocity And Its Anisotropy Of Polymer Modified High-Volume Class-F Fly Ash-Kaolinite Mixtures, X. Kang, B. Bate

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigated the effects of polymers on the small-strain stiffness behavior of high-volume Class-F fly ash-kaolinite mixtures. The shear wave velocity (Vs) and its anisotropy of organically modified fly ash-kaolinite mixtures were evaluated using a self-developed floating wall type consolidometer bender element (BE) testing system. Both synthetic polymers [polyethylene oxide (PEO)] and biopolymers (xanthan gum and chitosan) were used to modify the stiffness of fly ash-kaolinite mixtures. Shear waves generated and received by bender elements were measured to quantify the small-strain stiffness of the organically modified fly ash-kaolinite mixtures in three orthogonal directions, i.e., vh, hv, and hh. The …

Dynamic And Static Behavior Of Hollow-Core Frp-Concrete-Steel And Reinforced Concrete Bridge Columns Under Vehicle Collision, Omar I. Abdelkarim, Mohamed Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents the difference in behavior between hollow-core fiber reinforced polymer-concrete-steel (HC-FCS) columns and conventional reinforced concrete (RC) columns under vehicle collision in terms of dynamic and static forces. The HC-FCS column consisted of an outer FRP tube, an inner steel tube, and a concrete shell sandwiched between the two tubes. The steel tube was hollow inside and embedded into the concrete footing with a length of 1.5 times the tube diameter while the FRP tube stopped at the top of footing. The RC column had a solid cross-section. The study was conducted through extensive finite element impact analyses …

Smart Rock Technology For Real-Time Monitoring Of Bridge Scour And Riprap Effectiveness -- Design Guidelines And Visualization Tools, Genda Chen, Yan Tang, Yizheng Chen, Zhaochao Li, Chuanrui Guo, Liang Fan, Yi Bao, Xiuyan Hu, Matthew Klegseth

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study aims to further develop and demonstrate the recently-proposed smart rock technology for scour depth and protection effectiveness monitoring. A smart rock is one or two stacked magnets encased in a concrete sphere with a specially-designed rotational mechanism. Design guidelines, rotational mechanisms, remote measurement tools and localization algorithms of smart rocks were developed and validated at three bridge sites. The effect of steel reinforcement in bridge piers/deck on the orientation of gravity-controlled magnets was negligible. The localization accuracy with a single smart rock met a general requirement of less than 0.5 m in engineering applications. The spherical smart rock …

Industrial Cold-Formed Steel Rack Column Base Fixity And Strength, Francesc Roure, Teoman Peköz, M. Rosa Somalo, Jordi Bonada, M. Magdalena Pastor, Miquel Casafont, James Crews

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper summarizes the testing done at the Universitat Politècnica de Catalunya, Barcelona, Spain and the possible use of the results in design for column base stiffness and strength. The test setup and procedure are adopted in the European rack design standards.

Reduced Order Models For Profiled Steel Diaphragm Panels, G. Bian, S. Torabian, B. W. Schafer

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The objective of this paper is to provide progress on development and validation of reduced order models for the in plane strength and stiffness of profiled steel panels appropriate for use in structural models of an entire building. Profiled steel panels, i.e, metal deck, often serve as a key distribution element in building lateral force resisting systems. Acting largely as an in-plane shear diaphragm, metal deck as employed in walls, roofs, and floors plays a key role in creating and driving three-dimensional building response. As structural modeling evolves from two-dimensional frameworks to fully three-dimensional buildings, accurate and computationally efficient models …

Shear Resistance Of Cold-Formed Steel Framing Wall With X-Strap Bracing, Chi-Ling Pan, Chang-Chan Huang, Meng-Hsiu Tsao

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This research is concentrated on the study of structural strength and behavior of cold-formed steel frame with strap bracing subjected to horizontal loads. The wall specimens with and without calcium silicate board sheathing were tested to compare the differences of shear resistance. Based on the test data, the ultimate strength, stiffness, ductility ratio, and failure behavior were studied for each specimen, and the wall’s movements were also discussed in this paper. The cold-formed steel framing wall without bracing from previous study was introduced for the comparison purpose. As expected, the ultimate strength was increased for the cold-formed steel wall sheathed …

An Archetype Mid-Rise Building For Novel Complete Cold-Formed Steel Buildings, S. Torabian, Z. Saneei Nia, B. W. Schafer

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper introduces an archetype mid-rise cold-formed steel (CFS) building that aids in assessing the limits of current structural solutions, particularly lateral force resisting systems, and also in the development of new CFS technologies. A unified archetype building provides a platform for comparing the performance of new lateral force resisting systems to existing ones. The study herein provides quantitative evaluation of the design limitations of a typical “complete” cold-formed steel building (i.e. only cold-formed steel based elements are used for all gravity and lateral force resisting systems) at different heights (4 through 20 stories) located in a high seismic zone. …

Seismic Modeling And Incremental Dynamic Analysis Of The Cold-Formed Steel Framed Cfs-Nees Building, J. Leng, S. G. Buonopane, B. W. Schafer

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The objective of this paper is to present seismic modeling of a two-story cold-formed steel (CFS) framed building. The selected building, known as the CFSNEES building, was designed to current U.S. standards and then subjected to full-scale shake table tests under the U.S. National Science Foundation Network for Earthquake Engineering Simulation (NEES) program. Test results showed that the building’s stiffness and capacity was considerably higher than expected and the building suffered only non-structural damage and no permanent drift, even at maximum considered earthquake (per ASCE 7 and the selected California site) level. Past modeling, including that of the authors, largely …

Experimental Investigation Of The Effect Of Screw Fastener Spacing On The Local And Distortional Buckling Behavior Of Built-Up Cold-Formed Steel Columns, David C. Fratamico, Shahabeddin Torabian, Kim J. R. Rasmussen, Benjamin W. Schafer

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper addresses an ongoing experimental and computational effort on the buckling and strength of built-up cold-formed steel (CFS) columns. Specifically, two 6 in. (152 mm) deep lipped channel sections (i.e. the 600S137-54 and 600S162-54 using AISI S200-12 nomenclature) are studied here in a back-to-back, screw-connected form and were chosen for their local and distortional slenderness to study the effect of fastener spacing and layout on local and distortional buckling and collapse behavior. Thirty column tests are completed with concentric loading. The screw spacing is varied from L to L/6, where L is the column length, with and without varying …

Experimental Investigation Into Steel Storage Rack Beam-To-Upright Bolted Connections, Liusi Dai, Xianzhong Zhao, Chong Ren

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

For unbraced steel storage racks, the down-aisle stability depends largely on the performance of beam-to-upright connections and column bases. Boltless connections are generally used in order to make rack structures easy to assemble and feasible to adjust the storey height. Recently, storage racks are designed to carry large amounts of goods and they are therefore raise a considerable height, which makes the improvement of the structural stability to be sufficiently important. Under the circumstances, tab-connected beam-to-upright connections with bolts are gradually used in steel storage racks. Compared with boltless connections, the stiffness, strength and ductility of the bolted connections are …

Behaviour Of Cold-Formed Steel Trusses With Concentric And Eccentric Joint Arrangements Using The Howick Rivet Connector, Amin Ahmadi, Colin K. L. Yee, Harry J. S. Shepherd, G. Charles Clifton, Raj Das, James B. P. Lim

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper considers the behaviour of a cold-formed steel truss system that uses a novel pinned connector for the joints, to be referred to as the Howick Rivet connector (HRC). Use of the HRC allows a pinned concentric joint arrangement to be formed, as well as the more usual eccentric joint arrangement used in tests described in the literature. However, with the concentric joint arrangement, it is necessary to remove part of the lips of the channel-sections being connected, thus creating a discontinuity in the lips. This paper assesses the effect of this discontinuity. Full-scale truss tests are first described. …

Design Of New Cold Rolled Purlins By Experimental Testing And Direct Strength Method, V. B. Nguyen, B. Cartwright, M. A. English

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

New cold roll formed channel and zed sections for purlins, namely UltraBEAMTM2 and UltraZEDTM2, have been developed by Hadley Industries plc using a combined approach of experimental testing, finite element modelling and optimisation techniques. The new sections have improved strength to weight ratio by increasing the section’s strength by using stiffeners in the section webs. The European standards, Eurocode 3, use a traditional Effective Width Method to determine the strength of a cold formed steel member. However, the design of the new sections UltraBEAMTM2 and UltraZEDTM2 using this method is very complicated in calculating the effective section properties as these …

Seismic Performance Investigation Of Cold-Formed Steel Framed Shear Walls With Steel Sheathing, Feng Ruo-Qiang, Xu Peng-Hui

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Cold-formed steel (CFS) framed shear walls with steel sheet sheathing can achieve higher shear resistance compared to conventional CFS framed shear walls. Experimental and numerical investigation of seismic behavior was present on two CFS shear walls sheathed with steel sheet for the base layer combined with gypsum wallboards for the face layer on both sides. Monotonic shear and cyclic loading tests were conducted on wall specimens. The failure mechanism, bearing capacity, stiffness and ductility of specimens were obtained. On the basis of rational simplification of CFS framed shear walls, the finite element software ABAQUS was used to simulate the monotonic …

An Improved Two-Stage Seismic Analysis Procedure For Mid-Rise Buildings With Vertical Combination Of Cold-Formed Steel And Concrete Framing, X. Yuan, L. Xu

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Presented in this paper is an improved two-stage analysis procedure for evaluating the seismic load of the mid-rise buildings with vertical combination of cold-formed steel and concrete framing. By comparing the improved procedure to the one prescribed in ASCE 7, it is found the stiffness requirement of the two-stage analysis procedure stated in ASCE 7 may be over-relaxed, which may consequently result in the underestimation of the base shear of the upper structure in certain cases. Furthermore, the lateral load at the top storey of the upper structure evaluated by ASCE 7 two-stage analysis procedure may also be considerably underestimated. …

Resistance Of Arc Spot Welds – Update To Provisions, B. Paige Blackburn, Thomas Sputo

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The AISI S100-12 provisions for arc spot welds have not be reviewed since 1999. This study performs a comprehensive analysis of the entire arc spot weld data base including data from four new research studies and reconsiders AISI S100-12 resistance equations with data from 450 specimens. Most AISI S100-12 equations were found to be conservative, particularly for sheet tearing failure modes. However, the equation for arc spot weld fracture under tensile load was found to poorly predict the data base test results. AISI S100-12 provision improvements are recommended not only for the resistance equations and factors, but also for the …