Civil and Environmental Engineering Commons^™

Results Of Application Of The Methods “Sologub” And Combinator Sorting In The Process Of Forming Multi-Group Trains At The Sorting Station, Sakijan Kabildjanovich Khudayberganov, Shinpolat Mansuraliyevich Suyunbayev, Sherzod Bakhrom Ugli Jumayev

Journal of Tashkent Institute of Railway Engineers

At present, the formation of multi-group freight trains in accordance with the established procedure at all marshalling yards of JSC Uzbek Railways is based on the experience of the relevant personnel. Therefore, one of the urgent tasks is to improve the process of forming such trains based on the introduction of modern technologies. This article presents the results of applying the Sologub methods and combinatorial sorting in the process of forming multi-group trains at the sorting station of JSC Uzbek Railways. The regularity of the dependence of the number of groups in a multi-group train on the required paths was …

Asynchronous Phase Rotor Generators For Power Planes Operating Parallel With A Network, Sharafiddin Kamaliddinovich Alimhodzhaev, Odil Umirzakovich Zakhidov, Mirzohid Hurramovich Taniev

Journal of Tashkent Institute of Railway Engineers

The article presents the results of studies of asynchronous generators of wind power plants and small hydroelectric power stations operating in parallel with the electric network. The parameters of the equivalent circuit are specified, on the basis of which the analytical dependence of the electromagnetic moment of the generator is found. It is proposed to take into account the revealed features of the mechanical characteristics of the generators that differ from the characteristics determined by the generally accepted analytical method

Comparative Analysis Of Functional Diagnostic Methods Of Traction Asynchronous Motors, Zhavkharbek Sulton Ugli Fayzullaev

Journal of Tashkent Institute of Railway Engineers

The article provides a comparative analysis of the methods of functional diagnostics of traction induction motors and justifies that of them the most promising are thermal, electric, vibroacoustic and magnetic methods. To obtain the most reliable information in diagnosing the technical condition of traction induction motors, it is recommended that the methods considered be used in conjunction with the simultaneous improvement of their technical means.

The Research Of Transient Processes In Current Transformers By The Operator's Method, Sultan Fayzullayevich Amirov, Shavkat Mukhsimov, Otabek Tashmuhammatovich Boltayev

Journal of Tashkent Institute of Railway Engineers

In the article the transient processes occurring in current transformers are investigated and the values of the magnetization current are determined by the operator method using the primary current source. Using the obtained results, the regularities of the magnetization current change in time are analyzed. For the investigated wide-range current transformer with a closed and open core, that is, at different values of T', a comparative analysis of the laws of change in time of the aperiodic components of the magnetic current was carried out. It is determined that current transformers with air gap are effective in all cases when …

On The Dynamics Of The Movement Carriage In The Accelerating Grable The Marshalling Yard, Shukhrat Umarkhodjaevich Saidivaliev, Zakhro Valijanovna Ergasheva

Journal of Tashkent Institute of Railway Engineers

The article presents the results of studies of the movement of the carriage on the slope hump (including brake position) when exposed to the forces of wind. Maintaining acceptable speed impacts and screening the Park can be achieved by changing the profiles of individual sections of the drain side hump or application of additional wagon retarders.

Incorporating Geophysical Data In Slope Stability Modeling For Two Slopes In Arkansas, Vanessa Lebow

Graduate Theses and Dissertations

Slope failures in the United States alone cause millions of dollars in damage to infrastructure, threaten national monuments, create environmental hazards, and take an average of 25-50 lives a year. With the inevitable construction that occurs on slopes, it is imperative that the slopes be properly designed which requires a thorough understanding of slope grade, subsurface soil conditions, soil strength parameters, water table locations, and depth to bedrock across the entire site. The preferred method of data collection would be to use borings and other in-situ methods; however, sometimes due to cost constraints or site accessibility only a very limited …

Evaluation Of Concrete Deck Curing Regimens Using Capillary Pressure Sensing System, Samuel Spann

Graduate Theses and Dissertations

Early-age plastic shrinkage cracking is a common problem with the construction of concrete bridge decks due to the high surface area-to-volume ratio and exposure to potentially detrimental environmental effects. Curing regimens are utilized to mitigate cracking risk during the plastic stage of the concrete; the curing regimens evaluated for this study were wet burlap-polyethylene sheeting, two acrylic curing compounds, and one lithium compound. Capillary pressure in the water filled pores has been shown to correlate to the plastic shrinkage cracking risk of concrete. A new portable system has been developed to measure the capillary pressure that could potentially be used …

Truck Activity Pattern Classification Using Anonymous Mobile Sensor Data, Taslima Akter

Graduate Theses and Dissertations

To construct, operate, and maintain a transportation system that supports the efficient movement of freight, transportation agencies must understand economic drivers of freight flow. This is a challenge since freight movement data available to transportation agencies is typically void of commodity and industry information, factors that tie freight movements to underlying economic conditions. With recent advances in the resolution and availability of big data from Global Positioning Systems (GPS), it may be possible to fill this critical freight data gap. However, there is a need for methodological approaches to enable usage of this data for freight planning and operations.

To …

Study Of Internal Strains Developed In Concrete Decks At Early Ages In Steel Continuous Bridges, Fernando R. Benitez Ortiz

Graduate Theses and Dissertations

The Arkansas Department of Transportation (ARDOT) has identified bridge deck cracking shortly after concrete decks are placed and prior to applying traffic loads. Previous researchers have confirmed improper construction practices and design methods can lead to deck cracking. Currently, many contractors throughout Arkansas are using continuous deck pours. This construction approach may restrict the concrete slab from movement during early age shrinkage, causing tensile stresses to develop. The final stresses at the end of construction must be lower than the concrete tensile strength, if not cracking issues will develop. Eventually, these cracks may enlarge due to service load stresses and …

Cytotoxicity And Mutagenicity Of Disinfection Byproduct Mixtures Formulated Using Free Chlorine And Monochloramine, Yonas Ghebremedhin

Graduate Theses and Dissertations

Bioassays have been used extensively to assess various toxicity endpoints of drinking water disinfection byproducts (DBPs), but an emphasis on single compounds prevails. In this research, DBP mixtures were assessed using a cytotoxicity test with Chinese Hamster Ovary (CHO) cells and an Ames fluctuation test with Salmonella typhimurium TA-98 and TA-100 with and without S9 rat liver homogenate. Seven whole mixture DBP concentrates were formulated using reconstituted natural organic matter (NOM) extracts from the Upper Mississippi River using scaled disinfectant dosing protocols with free chlorine and monochloramine in the presence and absence of added bromide. DBPs were identified by gas …

Weigh-In-Motion Auto-Calibration Using Automatic Vehicle Identification, Fu Ren Zhang Zhang Durandal

Graduate Theses and Dissertations

Weigh-in-Motion (WIM) sensors are installed on mainline lanes at highway locations to record vehicle weights, axle spacing, vehicle class, travel speed, vehicle length, and traffic volume. These data elements support effective transportation planning, infrastructure design, and policy development. Therefore, it is important that WIM sensors supply accurate data. After initial installation and calibration, WIM systems may experience measurement drifts in weight and axle detection. Recalibration takes two general forms: (a) On-site calibration involving running trucks of known weight over WIM scales and (b) Auto-calibration methods involving comparisons to assumed reference weights. Auto-calibration can be more cost and time effective than …

Evaluation Of Fracture Principles In Asphalt Concrete Utilizing The Sc(B) Geometry, Airam Marlee Morales Vega

Graduate Theses and Dissertations

Since cracking is one of the principal distresses to be considered in asphalt concrete, multiple fracture tests and geometries have been used to quantify cracking resistance. One of the most popular geometries that have been used in fracture tests is the Semi-Circular bend (SC(B)). However, for this geometry, most of the fracture test methods use different parameters such as thickness, testing temperatures, and loading rates. Thus, the purpose of this research was first to evaluate fracture energy by performing a ruggedness test based on ASTM E1169. Then, to apply fracture mechanics concepts to evaluate three specimen thicknesses (25, 50, and …

The Bridge Newsletter Winter 2019, Missouri University Of Science And Technology

The Bridge Newsletter

-Dehghani joins S&T
-Life after death of solar panels
-Civil engineering senior studies in Hong Kong
-Planning for future climate changes in the Artic

Small Ruminant Health Intervention Calendar In Ethiopia, Mesfin Mekonnen, Ayalew Assefa, Tesfalem Nane, Firdawok Ayele, Asrat Arke, Belay Elias, Barbara Wieland

Daugherty Water for Food Global Institute: Faculty Publications

Contents

1 Background................................................................................................... 3
2 Developing the health intervention calendar............................................................ 4
The treatment calendar ......................................................... 4 Applying the calendar..................................................................... 5 4 References................................................................... 8

Impacts Of Construction Material Delay In Iraq, Omar Raad Abdullah

Civil Engineering Theses - Archive

The construction industry is considered one of the most important industries in Iraq. It is well known that most construction projects in this country can experience missed deadlines and cost overruns or both. The main objectives of this study are to evaluate the impact of construction material shortages and to determine the most important problems causing these shortages in Iraq. Above objectives are achieved through a literature review and a survey, which include a questionnaire used to assess the perceptions of the main participants involved in the construction of different types of projects, such as infrastructure, residential, highways and medical …

Experimental Investigation Of Utilizing Steel Fiber As Concrete Reinforcement In Bridge Decks, Samed Al Khafaji

Civil Engineering Theses - Archive

Research on utilizing steel fiber vs concrete reinforcement in bridge deck to replace more traditional reinforcing bars is sparse, therefore a research into this topic is interesting to identity opportunities for speeding up of construction by avoiding laying and tying reinforcement and verifying clear cover to reinforcing bars which is one of the most time-consuming processes involved in construction. This study investigates the efforts of steel fiber on the bridge deck from the strength and economical implementation. Four concrete mix design with vary steel fiber dosages of 0.0%, 0.5%, 1.0%, and 1.5% used in this study. The physical properties of …

Assembly-Scale And Whole-Building Energy Performance Analysis Of Ultra-High-Performance Fiber-Reinforced Concrete (Uhp-Frc) Façade Systems, Bahram Abediniangerabi

Civil Engineering Dissertations - Archive

The majority of building energy consumption is used to heat and cool enclosed spaces. An innovative ultra-high-performance fiber-reinforced concrete (UHP-FRC) façade system could potentially reduce this energy consumption by utilizing UHP-FRC’s high structural strength and ductility hence more space for insulation. The energy performance assessment of innovative façade systems such as UHP-FRC panels could be misleading if the effect of building types and climate contexts on building energy consumption is not considered. Moreover, thermal bridging and hygrothermal analyses of UHP-FRC panels are needed to investigate the heat and moisture transfer within the panels. The main objectives of this study are …

Evaluation Of The Structural Performance Of Bridge Mse Retaining Walls, Zaid Sm Momani

Civil Engineering Dissertations - Archive

Mechanically Stabilized Earth (MSE) walls have been used extensively since the first MSE wall constructed in California in the early 70’s. MSE walls proved that they are reliable, cost-effective, aesthetically pleasing, and easily constructible. However, the design criteria of an MSE wall does not always incorporate the comprehensive behavior. A reasonable number of MSE walls do not perform as expected; a few experienced catastrophic failure. The current study was inspired by multiple MSE walls showing excessive movement of the precast panels in Fort Worth and Hurst, Texas. Three most critical MSE walls were selected for this study. The main focus …

Effect Of Sewage Sludge And Wastewater Recirculation On The Degradation Of Municipal Solid Waste In Bioreactors, Afroza Ayub

Civil Engineering Theses - Archive

Municipal Solid Waste (MSW) management is the major environmental and economical concern for the world. Among all the MSW management alternatives, sustainable Bioreactor has potential to solve environmental and economic concerns related to organic waste. This potential of Sustainable Bioreactor can be enhanced by accelerated decomposition of waste. Accelerated decomposition of organic fraction of MSW can be achieved by the addition of nitrogen rich, macro and micro nutrients such as sludge and manures. Several studies have been conducted by using sludge as inoculum for degrading organic fraction of MSW in the anaerobic digester. However, this study is to compare the …

Effect Of Substrate To Inoculum Ratio On Bioenergy Recovery From Food Waste, Yard Waste, And Biosolids By High Solids Anaerobic Digestion, Phillip J. Dixon, Sarina J. Ergas, James R. Mihelcic, Shakira R. Hobbs

Civil Engineering Faculty Publications

Residual biosolids from wastewater treatment facilities and the organic fraction of municipal solid waste (OFMSW), such as food and yard wastes (FW and YW), are difficult to manage due to increased waste generation and recent stringent regulations. This study investigated the effect of substrate to inoculum ratio (S/I) on biochemical transformation mechanisms and biomethane production during high solids anaerobic digestion of FW, YW, and biosolids. Biochemical methane potential (BMP) assays were set up under mesophilic conditions at S/I of 1.0, 2.0, and 3.0 g OFMSW total solids (TS)/g inoculum TS. BMP with the lowest S/I (1.0) produced the highest cumulative …

Enhancements Of Shear Tests For Asphalt Concrete, Yazeed Suleiman Jweihan

Civil Engineering Dissertations - Archive

The measurement of the fundamental shear properties of asphalt mixes is imperative to the improvement of modelling of rutting development in asphalt concrete. The Duplicate Shear Tester (DST) is a recent device developed at the University of Texas at Arlington as a replacement to the Superpave Shear Tester (SST). It measures the average shear properties of two asphalt concrete specimens at the same time. It has ability to perform the two common SST tests: the FSCH and RSCH in according to the standard test method AASHTO T-320. Although the DST has successfully satisfied the objectives of being a reliable, inexpensive …

Physical Characterization And Evaluation Of Energy Potential For Mined Waste From Irving Landfill, Vijay Kakara

Civil Engineering Theses - Archive

Historically landfills have been seen as the ultimate solution for storing waste at minimum cost. But, now it is a well-known fact that these deposits have numerous implications such as long term methane emissions, local pollution and many space-related issues etc. In most parts of the world, however, landfilling is the most common method to dispose waste. Even developed countries with recycling and waste treatment facilities have been no exception in landfilling. Therefore over the years, several old and operating landfills have been accumulated with an enormous amount of obsolete materials and products. To address such issues related to waste …

Driveability Of Recycled Plastic Pin (Rpp) In North Texas, Arif Mohammad Aziz

Civil Engineering Theses - Archive

The Recycled Plastic Pins (RPP) have been extensively used as an alternative to the conventional slope stabilization methods in stabilizing shallows slope failure in Texas, Missouri, Kansas, and Idaho in the United States. The RPP provides additional resistance along the potential slip surface when it is driven into the slope and increases the factor of safety. RPPs are fabricated from recycled plastics and waste materials (i.e. polymers, sawdust, and fly ash), and is nondegradable in nature. It is found to be very useful and beneficial engineering materials for civil engineering infrastructure projects. The cost-effectiveness of using any engineering material largely …

A Critical State Approach To The Mechanical Behavior Of Early-Age Cemented Paste Backfill, Amin B. Ghorbanpour

Civil Engineering Dissertations - Archive

Low plasticity to non-plastic mine tailings are typically transported to a storage area through pipelines in form of slurry or thickened tailings. The main concern with such tailings deposits is the possibility of liquefaction and the consequent failure of the tailings retaining dams. Tailings can also be used as Cemented Paste Backfill (CPB) material to fill previously mined underground voids. The state of practice to improve the mechanical properties of tailings is to add a small quantity of cementitious materials or binder agents. Portland cement (PC) is the most common binder agent that is used to improve the mechanical properties …

Effect Of Chicken Manure On Methane Production From Msw In Lab Scale Anaerobic Reactors, Md Tauhidul Islam

Civil Engineering Theses - Archive

One of the major problems of urbanization is the production of a huge amount of Municipal Solid Waste. The cities and metropolitan areas are generating more and more solid waste and these wastes are filling up the landfill rapidly. Creating new landfills after a few years is not a solution as there is not much space in urban areas. Moreover, making the landfills far away from cities is not economically viable as longer hauling distance increases the cost. In this scenario, Bioreactor landfill is a viable solution to this problem. Bioreactor landfills can save a lot of space and it …

Splice Performance Of #6 Reinforcing Bars In Masonry With Self-Consolidating Grout, Annie Ruth Nielson

Theses and Dissertations

Reinforced masonry grouted using self-consolidating grout (SCG) is a relatively new and economically competitive option for construction, providing advantages such as reduced construction time, decreased noise and vibration, and reliable consolidation. However, SCG has different properties than conventional grout and its performance should be verified using current governing code requirements. The purpose of this research program was to determine the development length of spliced reinforcing bars in masonry grouted with SCG.Twelve masonry panels, four courses high and two and a half blocks wide, were constructed using 8-inch concrete masonry units, each with two pairs of vertically spliced #6 reinforcing bars. …

An Application Of Bayesian Multilevel Model To Evaluate Variations In Stochastic And Dynamic Transition Of Traffic Conditions, Emmanuel Kidando, Ren Moses, Thobias Sando, Eren Erman Ozguven

Civil and Environmental Engineering Faculty Publications

© 2019, The Author(s). This study seeks to investigate the variations associated with lane lateral locations and days of the week in the stochastic and dynamic transition of traffic regimes (DTTR). In the proposed analysis, hierarchical regression models fitted using Bayesian frameworks were used to calibrate the transition probabilities that describe the DTTR. Datasets of two sites on a freeway facility located in Jacksonville, Florida, were selected for the analysis. The traffic speed thresholds to define traffic regimes were estimated using the Gaussian mixture model (GMM). The GMM revealed that two and three regimes were adequate mixture components for estimating …

Study On Dye-Sensitized Solar Cells Based On Tio2 Composite Nanomaterials, Cuiping Kang, Muhammad Aqeel Ashraf, Yung-Tse Hung

Civil and Environmental Engineering Faculty Publications

With the continuous development of nanomaterials, how to improve the conversion efficiency of DSSCs has been the focus of scholars. Nano-TiO2 material is a wide bandgap semiconductor with a bandgap of 3.2eV. It exhibits good performance in dye adsorption, charge separation, electron transport, etc., and has good chemical stability and strong acid and alkali resistance. Therefore, it was always the material of choice for the preparation of photoanodes. In this paper, different thicknesses of TiO2 NRs barrier layers were prepared on FTO substrates by solvothermal method and two-step spin coating method, and their electrochemical and photoelectric properties were tested by …

Synthesis Of Metakaolin-Based Geopolymer And Its Performance As Sole Stabilizer Of Expansive Soils, Rinu Ann Samuel

Civil Engineering Dissertations - Archive

Expansive soils have been stabilized using conventional soil stabilizers such as lime and cement for many decades. These conventional stabilizers form cementitious productions that enhance the strength properties and reduce the swelling and shrinkage potential of expansive soils. However, the energy-intensive production operations of conventional soil stabilizers release substantial amounts of harmful greenhouse gases into the atmosphere. In addition, conventional soil stabilizers are also prone to durability issues, which make them somewhat ineffective as long-term solutions. Furthermore, the use of calcium-based stabilizers cause excessive swelling and shrinkage in sulfate-bearing subgrade soils due to the formation of highly expansive minerals like …

Development Of A Flexible Pavement Design Protocol For The Uae Based On The Mechanistic-Empirical Pavement Design Guide, Ammar Hassan Alalkim Alzaabi

Civil Engineering Dissertations - Archive

The Ministry of Infrastructure Development in the UAE has used the AASHTO 1993 Pavement Design Guide for the design of new flexible pavement structures for many years. An improved pavement design method, called the Mechanistic-Empirical Pavement Design Guide (MEPDG) was developed by AASHTO in their effort to update the empirical method used in 1993 Guide. The project was initiated by the National Cooperative Highway Research Program (NCHRP) 1-37A project. It is based on mechanistic-empirical analysis of the pavement structure to predict the performance of the pavements subject to pavement structure and materials, traffic and environmental conditions. The development allowed for …