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2023

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Articles 901 - 930 of 1746

Full-Text Articles in Civil and Environmental Engineering

Analysis On Vehicle‐Bridge Interaction Of High‐Pier Continuous Rigid Frame Bridge, Liu Huaquan, Yang Dehai, Cai Chengqi, Huang Zhenming, Chen Zhouqi May 2023

Analysis On Vehicle‐Bridge Interaction Of High‐Pier Continuous Rigid Frame Bridge, Liu Huaquan, Yang Dehai, Cai Chengqi, Huang Zhenming, Chen Zhouqi

Journal of China & Foreign Highway

To study the dynamic response characteristics of the vehicle-bridge system under moving vehicle loads, a three-span high-pier continuous rigid frame bridge was selected as the research object. A 2-axle, 7-degree-of-freedom vehicle model was applied to explore the effects of vehicle speed, number of vehicles, and vehicle load on the dynamic response of the vehicle-bridge system. The results show that vehicle speed has minimal impact on the peak displacement response of the bridge. However, when vehicles travel at the same speed, the peak displacement response differs across bridge spans, with resonance occurring at a vehicle speed of 40 km/h. As the …


Research On Application Of Equivalent Stiffened Plate Elements In Local Stability Calculation Of U‐Shaped Stiffened Plates, Chen Xiangjun May 2023

Research On Application Of Equivalent Stiffened Plate Elements In Local Stability Calculation Of U‐Shaped Stiffened Plates, Chen Xiangjun

Journal of China & Foreign Highway

To address the issue of excessively large computational models in the numerical simulation of U-shaped stiffened plates in large-span flat steel box girder main girders, this paper proposes a finite element calculation theory using equivalent stiffened plate elements and a simplified method for U-shaped stiffened plates. By simplifying the U-shaped small box ribs in U-shaped stiffened plates into equivalent stiffening strips, the transverse stiffness of the cover plate is redistributed, and the effect of equivalent stiffeners on the stress of the plates is calculated. Stability analysis was conducted using Fortran language developed on the Ansys platform, and the results were …


Optimization Research Of Laying Method And Material Type Selection Of Thermal Insulation Layer For Tunnels In Cold Region, Wu Tao, Liu Zhichun, Liu Xuejiao, Zhang Hongfei May 2023

Optimization Research Of Laying Method And Material Type Selection Of Thermal Insulation Layer For Tunnels In Cold Region, Wu Tao, Liu Zhichun, Liu Xuejiao, Zhang Hongfei

Journal of China & Foreign Highway

To address the issue of frost damage in tunnels in cold regions, research on thermal insulation and frost prevention is crucial. This paper utilizes an improved analytic hierarchy process combined with grey relational analysis to identify optimal insulation materials suitable for different laying methods that provide effective insulation. Numerical simulation methods were then used to calculate and analyze the tunnel temperature field under various combinations of insulation materials and laying methods. Based on the “composite temperature field” comparison results, the optimal insulation scheme was determined. The results show that the “off-wall laying + Furritek insulation board” combination is the optimal …


Experimental Study On Influence Of Phosphorus Slag Powder On Pervious Concrete, Lou Jianxin, Yang Jianyong, Zhang Yuxian, Li Jun, Wang Jie, Liu Jian May 2023

Experimental Study On Influence Of Phosphorus Slag Powder On Pervious Concrete, Lou Jianxin, Yang Jianyong, Zhang Yuxian, Li Jun, Wang Jie, Liu Jian

Journal of China & Foreign Highway

This paper investigates the effects of replacing cement with phosphorus slag powder on the mechanical properties, permeability, and pavement performance of pervious concrete. The results show that incorporating a certain amount of phosphorus slag powder as a partial replacement for cement in pervious concrete is feasible. When the replacement ratio of phosphorus slag powder is within 10%, it enhances the strength of pervious concrete. The optimal replacement ratio of phosphorus slag powder is 8%, achieving a compressive strength of 24.18 MPa, a void ratio of 15.37%, and a permeability coefficient of 2.45 mm/s, which meet the requirements for fully permeable …


Dynamic Load Response Analysis Of Rubber Powder Modified Asphalt Mixture, Yang Sanqiang, Sun Shuang, Li Qian, Liu Xinlei, Qin Lusheng May 2023

Dynamic Load Response Analysis Of Rubber Powder Modified Asphalt Mixture, Yang Sanqiang, Sun Shuang, Li Qian, Liu Xinlei, Qin Lusheng

Journal of China & Foreign Highway

To investigate the mechanical response of rubber powder modified asphalt pavement under dynamic loads, this paper, based on the “Full-Scale Accelerated Pavement Loading Testing” project, designed experimental schemes for asphalt mixtures with varying rubber powder contents. The paper employed accelerated loading test equipment to evaluate the stress and deformation of pavement structures, obtaining dynamic strain response data to analyze the strain response patterns of various structural layers. Combining finite element numerical simulations and a custom loading program, the paper examined the dynamic responses of rubber powder modified asphalt pavements under variable temperature conditions. The results show that through microscopic testing, …


Aging Asphalt Concrete Cracking Performance Under Different Cyclic Loading Frequencies, Yan Jingchen, Ma Yanpei, Yan Junjie May 2023

Aging Asphalt Concrete Cracking Performance Under Different Cyclic Loading Frequencies, Yan Jingchen, Ma Yanpei, Yan Junjie

Journal of China & Foreign Highway

Using digital speckle technology, this paper examines the crack propagation behavior of asphalt concrete under repeated loading, analyzing the crack propagation mechanism from macro- and micro-perspectives under different aging conditions and loading frequencies for four types of asphalt concrete. The results show that the basalt fiber-reinforced asphalt concrete beam specimens delay the onset of the unstable crack propagation phase, thus extending the service life of the asphalt concrete. Aging accelerates the progression of asphalt concrete to the unstable crack propagation point, advancing this stage by 4%-5%. Under repeated loading frequencies of 5 Hz, 10 Hz, and 15 Hz, the damage …


Design And Development Of Two And Three Dimensional Integration System For Highway Based On Webgis, Che Defu, Zhou Huajun May 2023

Design And Development Of Two And Three Dimensional Integration System For Highway Based On Webgis, Che Defu, Zhou Huajun

Journal of China & Foreign Highway

To address the inefficiencies, lengthy cycles, and high resource demands in the process of determining the annual project database for highway maintenance quotas in Liaoning Province, a 2D and 3D integration system for highways based on WebGIS was designed and developed. This system not only provides a macroscopic view of the geographic distribution and overall characteristics of highways but also offers a detailed and intuitive representation of the spatial relationships and conditions of roadbeds and pavement damage. The system meets the needs of modern highway management and can serve as a reference for other highway maintenance quota tasks.


Study On Relationship Of Solar Radiation Temperature And Pier‐Top Displacement Of Ultra‐High Thin‐Walled Hollow Pier, Liu Zhishen, Zhang Yifei, Song Fei, Su Jufeng, Ren Xiang May 2023

Study On Relationship Of Solar Radiation Temperature And Pier‐Top Displacement Of Ultra‐High Thin‐Walled Hollow Pier, Liu Zhishen, Zhang Yifei, Song Fei, Su Jufeng, Ren Xiang

Journal of China & Foreign Highway

Thin-walled hollow piers are widely used in high-pier and long-span continuous rigid-frame bridges. Solar radiation-induced displacements at the tops of ultra-high thin-walled hollow piers can negatively affect the structural alignment and stress during construction and post-construction phases. Based on a 180 m high thin-walled hollow pier of a large bridge in Shaanxi Province, this paper analyzes the temperature field and pier-top displacement using data collected during two 24-hour periods: August 28-29 and October 11-12. The temperature field and pier-top displacement patterns over time were studied using finite element analysis. The results show that the temperature difference between the north and …


Model Test Study On Mechanical Characteristics Of Spherical Joints In Multi‐Point Support Swivel System, Zeng Lifei May 2023

Model Test Study On Mechanical Characteristics Of Spherical Joints In Multi‐Point Support Swivel System, Zeng Lifei

Journal of China & Foreign Highway

As a critical load-bearing component in bridge swivel systems, the mechanical behavior of spherical joints is essential for the safety of bridge swiveling operations. This study focuses on the spherical joints of a multi-point support swivel system for the bridge over the Xiangyang North Marshalling Yard. Model tests were conducted to analyze the effects of the number of supporting legs, swivel speed, track smoothness, and wind load on the stress of spherical joints. The stress variation patterns of spherical joints under different working conditions were investigated. The results show that increasing the number of supporting legs improves the uniformity of …


Selection Of Phase Change Materials For Asphalt Pavement Based On Molecular Dynamics Simulation, Liu Fujun, Tian Xin, Liang Meichen, Guo Meng May 2023

Selection Of Phase Change Materials For Asphalt Pavement Based On Molecular Dynamics Simulation, Liu Fujun, Tian Xin, Liang Meichen, Guo Meng

Journal of China & Foreign Highway

Phase change materials (PCMs) have significant application potential in temperature regulation for asphalt pavements. To select suitable PCMs for road applications, this paper utilizes molecular dynamics simulation to analyze the molecular behaviors of lauric acid and polyethylene glycol (PEG). Experimental studies were conducted to validate the simulation results. The results show that molecular dynamics simulation provides an efficient and convenient method for comparing the performance of PCMs. PEG outperforms lauric acid in terms of molecular density, cohesive energy density, solubility parameters, and thermal conductivity, making it more suitable as a phase change material for asphalt pavements.


Study On Alkali Excitation Mechanism Of Large Dosage Slag Fine Powder, Mei Yang May 2023

Study On Alkali Excitation Mechanism Of Large Dosage Slag Fine Powder, Mei Yang

Journal of China & Foreign Highway

To reveal the alkali excitation mechanism of high-dosage slag, this paper combines a three-factor, three-level orthogonal design with macro- and micro-performance tests and microstructure analysis. The effects of different activators, including Ca(OH)2, Na2SiO3, Na2SO4, and CaSO4, in single and dual combinations on the initial and final setting times, pore solution pH, and strength of concrete were explored. The results show that the impact on the strength of hardened paste of composite cementitious materials is ranked as: activator type > dosage > dual-mix ratio. The optimal dual-mix dosage is 4%, with the best combination being Ca(OH)2 and Na2SiO3 at a ratio of 5:1. …


Study On Microstructure Of Asphalt Modified By Oil‐Coal Blend, Guo Pengfei, Zhou Xinfeng May 2023

Study On Microstructure Of Asphalt Modified By Oil‐Coal Blend, Guo Pengfei, Zhou Xinfeng

Journal of China & Foreign Highway

To investigate the microstructure and modification mechanism of asphalt modified with oil-coal blend, SK-90# asphalt was mixed with 5%, 10%, 15%, 20%, and 25% (external blending method) oil-coal blend to produce modified asphalt. The performance and microstructural changes of the modified asphalt were analyzed using contact angle testing, infrared spectroscopy, cross-sectional SEM, and X-ray photoelectron spectroscopy. The results show that the oil-coal blend exhibits good compatibility with asphalt. During the modification process, esterification reactions occurred, resulting in a decrease in hydroxyl-containing aromatic compounds and an increase in carbonyl-containing aromatic compounds. Macroscopically, the oil-coal blend-modified asphalt demonstrated excellent high-temperature performance.


Analysis Of Expressway Routine Maintenance Performance Management Based On Dea, Li Yuhuan, Shi Xiaoli, Gao Nan May 2023

Analysis Of Expressway Routine Maintenance Performance Management Based On Dea, Li Yuhuan, Shi Xiaoli, Gao Nan

Journal of China & Foreign Highway

To allocate maintenance resources efficiently and improve management levels, this paper examines the maintenance performance and improvement strategies of routine maintenance projects for 23 expressways in Shaanxi Province using 2018 operational maintenance data and data envelopment analysis. The results show that for some inefficient subsidiaries, traditional radial- and slack-based performance improvement methods are challenging and impractical in the short term. Therefore, a scenario-dependent model-based long-term incremental improvement strategy is proposed. By leveraging relative improvement values, this strategy enables phased improvements for inefficient subsidiaries. It provides a feasible approach for subsidiaries to set lower short-term performance improvement targets while achieving gradual …


Swietenia Mahagoni Leaves Extract: Antifungal, Insecticidal, And Phytochemical Analysis, Wael M. Khamis, Ahmed A. Heflish, Sarah El-Messeiry, Said I. Behiry, Abdulaziz A. Al-Askar, Yiming Su, Ahmed Abdelkhalek, Mohamed K. Gaber May 2023

Swietenia Mahagoni Leaves Extract: Antifungal, Insecticidal, And Phytochemical Analysis, Wael M. Khamis, Ahmed A. Heflish, Sarah El-Messeiry, Said I. Behiry, Abdulaziz A. Al-Askar, Yiming Su, Ahmed Abdelkhalek, Mohamed K. Gaber

Civil and Environmental Engineering Faculty Publications

In this study, we investigated the antifungal properties of an acetone extract derived from the leaves of Swietenia mahagoni (SMAL) against two isolated fungi, Fusarium equiseti (OQ820153) and Rhizoctonia solani (OQ820152), from rice sheath. The extract was effective in inhibiting the growth of both fungi at the highest concentration tested, 3000 μg·mL−1. Laboratory tests on the LC20 of SMAL extract (49.86 mg·L−1) versus pyriproxyfen 10% EC (1.96 mg·L−1) were accomplished on Aphis gossypii Glover. The extract potently reduced the survival of the nymphs (49.58%) more than the other treatments. The longevity of nymphs treated …


Review: Inelastic Constitutive Modeling: Polycrystalline Materials, Mirza Baig, Josiah Owusu-Danquah, Anne A. Campbell, Stephen F. Duffy Phd, Pe May 2023

Review: Inelastic Constitutive Modeling: Polycrystalline Materials, Mirza Baig, Josiah Owusu-Danquah, Anne A. Campbell, Stephen F. Duffy Phd, Pe

Civil and Environmental Engineering Faculty Publications

This article provides a literature review that details the development of inelastic constitutive modeling as it relates to polycrystalline materials. This review distinguishes between inelastic constitutive models that account for nonlinear behavior at the microstructural level, time-independent classic plasticity models, and time-dependent unified models. Particular emphasis is placed on understanding the underlying theoretical framework for unified viscoplasticity models where creep and classical plasticity behavior are considered the result of applied boundary conditions instead of separable rates representing distinct physical mechanisms. This article establishes a clear understanding of the advantages of the unified approach to improve material modeling. This review also …


Framework For Applicability Of Fidic Red Book (1999) For Contracts Governed By Law No. 182 Of The Year 2018 For Regulating Contracts Concluded By Public Entities, Fredy Ayad May 2023

Framework For Applicability Of Fidic Red Book (1999) For Contracts Governed By Law No. 182 Of The Year 2018 For Regulating Contracts Concluded By Public Entities, Fredy Ayad

Theses and Dissertations

An administrative contract is a type of contract that the administrative body enters in order to achieve a public interest. In Egypt, administrative contracts are governed by Law No. 182 of the year 2018 for Regulating Contracts concluded by Public Entities, which has been promulgated in October 2018. This Law includes several mandatory rules, which will govern over any conditions in the construction contract.

The FIDIC Red Book 1999 is widely used in Egypt and the Middle East in private sector and is currently also being utilized by governmental bodies. However, some contractors are not aware of the major deviations …


Development Of Carbon Emission Assessment Tool Towards Promoting Sustainability In Cal State La, Arezoo Khodayari, Soumya Puvvada, Jamaie M. Scott, Chandra Mouli Rotta, Geeth Sekhar Chadalawada, Jivar Afshar, Carlos D. Linares, Brad Haydel May 2023

Development Of Carbon Emission Assessment Tool Towards Promoting Sustainability In Cal State La, Arezoo Khodayari, Soumya Puvvada, Jamaie M. Scott, Chandra Mouli Rotta, Geeth Sekhar Chadalawada, Jivar Afshar, Carlos D. Linares, Brad Haydel

CSU Journal of Sustainability and Climate Change

The great demand for the burning of fossil fuels has greatly increased greenhouse gases (GHG) concentrations in the atmosphere. An increase in the atmospheric concentrations of greenhouse gases produces a positive climate forcing or warming effect [EPA, Climate Change Indicators]. Therefore, mitigation of GHG concentrations is important to prevent long-term impacts on the environment. On April 4, 2016, California State University, Los Angeles signed the most comprehensive of Second Nature’s three Climate Leadership Commitments, the Climate Commitment. Following this commitment, California State University, Los Angeles, set the ambitious goal of operational carbon neutrality by the year 2040. To assist California …


Improving The Cotton Simulation Model, Gossym, For Soil, Photosynthesis, And Transpiration Processes, Sahila Beegum, Dennis Timlin, Kambham Raja Reddy, Vangimalla Reddy, Wenguang Sun, Zhuangji Wang, David Fleisher, Chittaranjan Ray May 2023

Improving The Cotton Simulation Model, Gossym, For Soil, Photosynthesis, And Transpiration Processes, Sahila Beegum, Dennis Timlin, Kambham Raja Reddy, Vangimalla Reddy, Wenguang Sun, Zhuangji Wang, David Fleisher, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

GOSSYM, a mechanistic, process-level cotton crop simulation model, has a two-dimensional (2D) gridded soil model called Rhizos that simulates the below-ground processes daily. Water movement is based on gradients of water content and not hydraulic heads. In GOSSYM, photosynthesis is calculated using a daily empirical light response function that requires calibration for response to elevated carbon dioxide ( CO2). This report discusses improvements made to the GOSSYM model for soil, photosynthesis, and transpiration processes. GOSSYM’s predictions of below-ground processes using Rhizos are improved by replacing it with 2DSOIL, a mechanistic 2D finite element soil process model. The photosynthesis …


Optimization Of The Self-Healing Efficiency Of Bacterial Concrete Using Impregnation Of Three Different Precursors Into Lightweight Aggregate, Omar Omar May 2023

Optimization Of The Self-Healing Efficiency Of Bacterial Concrete Using Impregnation Of Three Different Precursors Into Lightweight Aggregate, Omar Omar

LSU Master's Theses

Concrete is the most broadly used construction material; thus, developing sustainable concrete is essential to decrease greenhouse gas (GHG) emissions from concrete production. Implementation of self-healing concrete technologies is a promising approach to enhance the durability and sustainability of the transportation infrastructure. Among these technologies, bacterial concrete has the potential to seal microcracks through microbial induced calcite precipitation (MICP). Bacterial protection is essential to ensure the viability of this technology due to concrete’s harsh environment. Additionally, the success of this technology depends on the presence of an adequate mineral precursor compound and nutrient for the bacteria. As such, the main …


Advancing The Economic And Environmental Sustainability Of The Newgenerator Nonsewered Sanitation System, Shion Watabe, Hannah A. C. Lohman, Yalin Li, Victoria L. Morgan, Lewis Stetson Rowles, Tyler Stephen, Hsiang-Yang Shyu, Robert A. Bair, Cynthia J. Castro, Roland D. Cusick, Daniel H. Yeh, Jeremy S. Guest May 2023

Advancing The Economic And Environmental Sustainability Of The Newgenerator Nonsewered Sanitation System, Shion Watabe, Hannah A. C. Lohman, Yalin Li, Victoria L. Morgan, Lewis Stetson Rowles, Tyler Stephen, Hsiang-Yang Shyu, Robert A. Bair, Cynthia J. Castro, Roland D. Cusick, Daniel H. Yeh, Jeremy S. Guest

Civil Engineering & Construction: Faculty Publications

Achieving safely managed sanitation and resource recovery in areas that are rural, geographically challenged, or experiencing rapidly increasing population density may not be feasible with centralized facilities due to space requirements, site-specific concerns, and high costs of sewer installation. Nonsewered sanitation (NSS) systems have the potential to provide safely managed sanitation and achieve strict wastewater treatment standards. One such NSS treatment technology is the NEWgenerator, which includes an anaerobic membrane bioreactor (AnMBR), nutrient recovery via ion exchange, and electrochlorination. The system has been shown to achieve robust treatment of real waste for over 100 users, but the technology’s relative life …


Downstream Hydrochemistry And Irrigation Water Quality Of The Syr Darya, Aral Sea Basin, South Kazakhstan, Bagdat Satybaldiyev, Baimurat Ismailov, Nurbek Nurpeisov, Kairat Kenges, Daniel D. Snow, Arindam Malakar, Omirzhan Taukebayev, Bolat Uralbekov May 2023

Downstream Hydrochemistry And Irrigation Water Quality Of The Syr Darya, Aral Sea Basin, South Kazakhstan, Bagdat Satybaldiyev, Baimurat Ismailov, Nurbek Nurpeisov, Kairat Kenges, Daniel D. Snow, Arindam Malakar, Omirzhan Taukebayev, Bolat Uralbekov

Daugherty Water for Food Global Institute: Faculty Publications

New hydrochemical measurements from the Syr Darya provide insights into factors affecting the composition and quality of a major freshwater source replenishing the Aral Sea. This river is heavily used for power and irrigation and crosses territories of four Central Asia republics. It is intensely managed, draining several major tributaries, many reservoirs, and numerous irrigation distribution systems and canals. Analysis of seasonal changes in dissolved ion concentrations using geochemical diagrams, elemental ratios, statistical correlation, and equilibrium modeling allowed the characterization of mineral formation processes that control the dissolved chemical composition. Measured water hydrochemistry and composition type differs substantially from previous …


Adaptation Of Concrete And Timber Bridge Railings For Low-Volume Traffic, Russell Masterson May 2023

Adaptation Of Concrete And Timber Bridge Railings For Low-Volume Traffic, Russell Masterson

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Bridge railings are a safety feature to protect the traveling public by containing and redirecting errant vehicles during run-off-road (ROR) events. Most bridge railing design and evaluation efforts have focused on ROR crashes on high-volume roads. Bridge railings for low-volume roads can be designed for lower impact speeds, so railings designed for high-volume roads are unnecessarily robust for low-volume applications and can be optimized to reduce costs for bridge owners while still providing adequate safety. The aim of this research has been focused on improving the design of two low-volume bridge railing systems for use by the United States Department …


The Effects Of Inaccurate And Missing Highway-Rail Grade Crossing Inventory Data On Crash And Severity Model Estimation And Prediction, Muhammad Umer Farooq May 2023

The Effects Of Inaccurate And Missing Highway-Rail Grade Crossing Inventory Data On Crash And Severity Model Estimation And Prediction, Muhammad Umer Farooq

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Highway-Rail Grade Crossings (HRGCs) present a significant safety risk to motorists, pedestrians, and train passengers as they are intersections where roads and railways intersect. Every year, HRGCs in the US experience a high number of crashes leading to injuries and fatalities. Estimations of crash and severity models for HRGCs provide insights into safety and mitigation of the risk posed by such incidents. The accuracy of these models plays a vital role in predicting future crashes at these crossings, enabling necessary safety measures to be taken proactively.

In the United States, most of these models rely on the Federal Railroad Administration's …


Song’S Site At Los Angeles Eco-Village Redevelopment, Kendall Gilbert, Marina Rios, Kristin Hernandez, Gianna Morelli May 2023

Song’S Site At Los Angeles Eco-Village Redevelopment, Kendall Gilbert, Marina Rios, Kristin Hernandez, Gianna Morelli

Honors Thesis

The Los Angeles Eco-Village (LAEV) is a co-op housing community, located in Koreatown, focused on building sustainable and economically cooperative living in an urban environment. The purpose of this project is to transform a property recently acquired by the LAEV, called Song’s, into a multipurpose community hub. The project design goals established with LAEV founder and community members, include cultivating new highly sustainable and resilient ideas on urban living and incorporating educational elements that inspire the community and visitors to live more sustainably. This project proposes three design elements to improve the community use of the newly acquired Song’s at …


Devlopment Of A Practical Method To Quantify Infiltration Rate Through Building Entrance, Eric Reed, Ferasuddin Siddiqui, Louidelson Deguerre, Steve. Boodram May 2023

Devlopment Of A Practical Method To Quantify Infiltration Rate Through Building Entrance, Eric Reed, Ferasuddin Siddiqui, Louidelson Deguerre, Steve. Boodram

Publications and Research

Infiltration through entrance doors, vestibules, cracks and other areas have a large impact in building energy consumption. It also has a significant impact on indoor air quality. There are only a few studies about air infiltration and air tightness in the literature. The purpose of this study is to develop practical methods to measure air infiltration rates through entrance doors. We have read research articles and identify several methods in the literature. Further investigation is required to help more accurately find infraction rate, crack size and location of cracks to help reduce air infiltration, energy costs, maintain comfortable indoor conditions …


Improvement Of A Low-Cost Diy Wave Gauge, Matthew F. Virden, Nigel A. Temple, Bret M. Webb, Eric L. Sparks May 2023

Improvement Of A Low-Cost Diy Wave Gauge, Matthew F. Virden, Nigel A. Temple, Bret M. Webb, Eric L. Sparks

Journal of Extension

The impacts of waves on shorelines and nearshore ecosystems has highlighted the need for extension and other environmental professionals to have access to accurate and affordable wave measurements. The development of a low-cost DIY wave gauge improved the accessibility of these measurements; however, the original design was limited in battery life. Here, an improved version of the low-cost DIY wave gauge, the DIY Feather Wave Gauge, is presented with the same performance, longer battery life, smaller design, and cheaper cost along with tutorials, parts lists, and other resources. This new gauge has been used to improve shoreline management recommendations.


Safety And Operational Assessment Of Rural Free Right-Turn Ramp Intersections, Jonathon Camenzind May 2023

Safety And Operational Assessment Of Rural Free Right-Turn Ramp Intersections, Jonathon Camenzind

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Free right-turn (FRT) ramps are alternative right-turn lane designs for intersecting highways. As of 2023, 79 FRT ramps exist at 68 rural highway intersections in Nebraska. FRT ramps may be located on three-legged or four-legged intersections and may be on the minor, the major, or both minor and major approaches of the same intersection.

This research compared the 68 rural FRT intersections to 24 similar non-FRT rural intersections to identify differences in crash frequency and crash rate and tested for statistical significance using a two-sample t-test. Crash data were obtained for the ten- year period of 2010-2019, with a focus …


Three-Dimensional Structural Analysis Of Temple 16 And Rosalila At Copan Ruinas, Luis Tuarez May 2023

Three-Dimensional Structural Analysis Of Temple 16 And Rosalila At Copan Ruinas, Luis Tuarez

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Temple 16 is an ancient Maya structure located at the heart of the Copán Ruinas Acropolis in Western Honduras. Temple 16 contains several earlier structures within it that were built on top of each other throughout Copán’s history. One of these earlier structures, Rosalila, is one of the most culturally significant structures within the Acropolis due to its preservation. An intricate series of archeological tunnels have been excavated throughout Temple 16 to allow for its study. However, significant cracking has been observed within Rosalila and several tunnels have experienced partial collapse. This not only poses a life safety issue for …


Occurrence Of Radionuclides And Hazardous Elements In The Transboundary River Basin Kyrgyzstan–Kazakhstan, Mariya A. Severinenko, Vladimir P. Solodukhin, Bekmamat M. Djenbaev, The National Academy Of Science Of The Kyrgyz Republic G. Lennik, Baktiyar T. Zholboldiev, Daniel D. Snow May 2023

Occurrence Of Radionuclides And Hazardous Elements In The Transboundary River Basin Kyrgyzstan–Kazakhstan, Mariya A. Severinenko, Vladimir P. Solodukhin, Bekmamat M. Djenbaev, The National Academy Of Science Of The Kyrgyz Republic G. Lennik, Baktiyar T. Zholboldiev, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Important for irrigation, the transboundary river basin between Kyrgyzstan and Kazakhstan is vulnerable to geochemical and anthropogenic sources of pollution. The use of water use indices, together with measurements of the elemental and radionuclide composition of the water and bottom sediments, provides a means for evaluating the continued use of the water from this region. Recent monitoring shows the highest concentrations of hazardous contaminants include lead and thorium contained in the bottom and banks of the Kichi-Kemin River. These contaminants are likely remnants of an accidental spill at the Aktyuz tailing dump in 1964. The specific activity of the Th-232 …


Innovative Research For Phosphorus Recovery In Freshwater Sediments, An Experimental Framework, John D. Collins May 2023

Innovative Research For Phosphorus Recovery In Freshwater Sediments, An Experimental Framework, John D. Collins

Honors College Theses

Phosphorus, a finite element, is necessary for all living organisms and directly impacts biota growth as well as productivity in freshwaters. The demand for phosphorus is continually increasing, but the supply of phosphorus is continually decreasing. In response to depleting resources, phosphorus in surface water sediments is being explored as a sustainable solution to the forecasted phosphorus shortage. Phosphorus in sediments is generally bound to oxidized iron (Fe3+) forming iron phosphate complexes. This form of phosphorus is released when iron reduces to Fe2+ in anaerobic environments. Under such conditions, soluble phosphorus (i.e., orthophosphate) may then be recovered using compounds that …