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Full-Text Articles in Engineering

Examining The Freezing And Thawing Behavior Of Concretes With Improved Performance Through Internal Curing And Other Methods, Wesley A. Jones Apr 2014

Examining The Freezing And Thawing Behavior Of Concretes With Improved Performance Through Internal Curing And Other Methods, Wesley A. Jones

Open Access Theses

Internally cured (IC) concrete has been emerging over the last decade as an effective way to improve the performance of concrete. IC holds promise for producing concretes with an increased resistance to early-age cracking and ultimately enhancing the durability of structures. It is a simple and effective way to ensure proper hydration of cementitious material in high performance concrete mixtures; mixtures in which traditional, external, curing can be ineffective. IC supplies water that is necessary to relieve stress buildup from chemical shrinkage and in turn helping to prevent early age shrinkage cracking.^ The first part of this thesis presents and …


Excessive Delays In Closeouts Can Be Removed With The Adaptation Of Better Practices, Vasudha Kaul Apr 2014

Excessive Delays In Closeouts Can Be Removed With The Adaptation Of Better Practices, Vasudha Kaul

Open Access Theses

Until recent times, closeout was not given its due diligence simply because the damage it created was not appreciated. Literature, thought-provoking discussions and thoughtful deliberations have punctuated the absolute need for a project closeout planning at the very beginning of a project. Many experienced project managers fail to plan the closeout of a job and concentrate solely on completing the contractual scope of work without paying much heed to the final percent of construction projects, the one percent that is an extremely time-consuming and expensive process if not catered for well in advance. The closeout stage is given its due …


The Hong Kong-Zhu Hai-Macau Bridge: Impacts On The Greater Pearl River Delta, Jun He Apr 2014

The Hong Kong-Zhu Hai-Macau Bridge: Impacts On The Greater Pearl River Delta, Jun He

Open Access Theses

This research looks at the impacts of megaprojects on their host regions through a case study of the Hong Kong-Zhu Hai-Macau Bridge (HZMB). The purpose of this study is to analyze the potential economic impact of the HZMB on the region through existing data and stakeholder interviews. The research will specifically focus on megaprojects' impacts on tourism industry and economic development in general. The research results are aimed to address the four research objectives of the study, which are similarities and differences between the HZBM and other megaprojects, common issues involved in developing megaprojects, the future impacts of the HZMB …


Risk-Based Bridge Inspection Practices, Rebecca Reising Apr 2014

Risk-Based Bridge Inspection Practices, Rebecca Reising

Open Access Theses

Improving bridge safety, reliability, and the allocation of bridge inspection resources are the goals of the proposed risk based bridge inspection practices. Currently, most bridges in the United States are inspected at a fixed calendar interval of 24 months, without regard to the condition of the bridge. Newer bridges with little or no damage are inspected with the same frequency as older, more deteriorated bridges thus creating inefficiency in the allocation of inspection resources. Because of limited resources, it is not possible to spend the necessary time examining bridges that are in poor condition and require extra attention since equal …


Investigating The Role Of Dem Resolution And Accuracy On Flood Inundation Mapping, Siddharth Saksena Apr 2014

Investigating The Role Of Dem Resolution And Accuracy On Flood Inundation Mapping, Siddharth Saksena

Open Access Theses

Saksena, Siddharth. M.S.C.E., Purdue University, May 2014. Investigating the Role of DEM Resolution and Accuracy on Flood Inundation Mapping. Major Professor: Venkatesh Merwade. Topography plays an important role in determining the accuracy of flood inundation maps. A lot of the current flood inundation maps are created using topographic information derived from Light Detection and Ranging (LiDAR) data. Although LiDAR data is very accurate, it is expensive, computationally time consuming and not available in several areas across the United States and around the world. As a result, coarser resolution DEMs which are easily available but less accurate are used for flood …


Floodplain Mapping Using Soil Survey Geographic (Ssurgo) Database, Nikhil Sangwan Apr 2014

Floodplain Mapping Using Soil Survey Geographic (Ssurgo) Database, Nikhil Sangwan

Open Access Theses

Floods are the most damaging of all natural disasters, adversely affecting millions of lives and causing financial losses worth billions of dollars every year across the globe. Flood inundation maps play a key role in assessment and mitigation of the potential flood hazards. However, there are several communities in the United States for which the flood risk maps have not been published yet, as the current flood inundation mapping methods are typically very expensive and time consuming. The objective of this study is to develop and examine an economical alternative approach to floodplain mapping using widely available soil survey data. …


Rheological Properties Of Laponite And Chemically Modified Laponite Suspensions, Meng Shen Apr 2014

Rheological Properties Of Laponite And Chemically Modified Laponite Suspensions, Meng Shen

Open Access Theses

This research investigates the rheological properties of concentrated laponite RD suspensions modified through the addition of laponite RDS and sodium pyrophosphate (SPP). The work is aimed at establishing the possible suitability of these materials for treating liquefaction susceptible sands. This application requires that a laponite suspension initially exhibits liquid like behavior and low viscosity that allow its delivery into the pore space of a sand, but that over time the suspension develop a gel structure with solid like behavior that can serve to restrict sand particle mobility during earthquake shaking.

The experimental program made use of a Physica MCR 301 …


Signalized Corridor Assessment, William Benjamin Smith Apr 2014

Signalized Corridor Assessment, William Benjamin Smith

Open Access Theses

Traffic engineers are often required to investigate the operation of a corridor and determine if there are any areas for improvement. Typical performance measures used to aid in the analysis are volume-to-capacity ratio and average delays based on the Highway Capacity Manual method. Signal timing software might also be used to adjust the split timings in effort to improve the corridor. This thesis discusses procedure to implement split timing optimization and delay analysis to enhance the current process of corridor assessment.

This study examined the newly opened US-231 bypass corridor outside of West Lafayette, IN. Initially, all intersections were operating …


Guidelines For Construction Companies To Decide Between Outsourcing And Self-Performing For Prefabricated Components, Sebastian Soto Ortiz Apr 2014

Guidelines For Construction Companies To Decide Between Outsourcing And Self-Performing For Prefabricated Components, Sebastian Soto Ortiz

Open Access Theses

Prefabrication and modularization has been used in the construction industry for decades. It has recently made a resurgence worldwide providing increased productivity, safety, quality and construction schedule. This research has focused on the situation where a construction company has decided to use prefabrication and faces two possibilities, they either will self-perform or they will outsource the construction of the prefabricated components. The decision making process used by a construction company to determine whether to outsource or self-perform prefabricated components is examined and analyzed.

Prefabrication is an industrial process in which certain components are manufactured in a specialized facility. These items …


Attached-Growth System For Nitrification At Low Temperature, Zhe Sun Apr 2014

Attached-Growth System For Nitrification At Low Temperature, Zhe Sun

Open Access Theses

Attached-growth biological treatment systems have potential to conduct nitrification in cold-temperature climates. In this research, in order to simulate the attached-growth nitrification process (using BOBBER biological reactor) at a real wastewater treatment facility, two laboratory-scale mini-BOBBER systems were installed in a temperature-controlled room and were operated for 101 days with pure ammonium chloride feed solution. Steady-state conditions were approached at 20°C, 15°C, 10°C, and 5°C. In addition, a series of batch experiments were conducted at temperatures of 20°C and 5°C to investigate the relationship between nitrification rate and ammonia-N concentration. Results from these experiments were analyzed and compared with the …


Retrofiting Lid Practices Into Existing Neighborhoods: Is It Worth It?, Timothy Wright Apr 2014

Retrofiting Lid Practices Into Existing Neighborhoods: Is It Worth It?, Timothy Wright

Open Access Theses

Low impact development (LID) practices are gaining popularity as a way to manage stormwater close to the source. This reduces infrastructure requirements and helps to maintain hydrologic processes close to predevelopment conditions. Studies have shown LID practices to be effective in reducing runoff and improving water quality. However, little has been done to aid decision makers in selecting the most effective practices for their needs and budgets.

To this end, the L-THIA LID model has been applied. Using readily available data sources, multiple scenarios can quickly be examined, and then analyzed to determine the cost of implementation and the approximate …


An Analysis On Causes Of Late Final Payment And Release Of Retainage: Electrical Subcontractors’ View, Xuejing Zhang Apr 2014

An Analysis On Causes Of Late Final Payment And Release Of Retainage: Electrical Subcontractors’ View, Xuejing Zhang

Open Access Theses

Using the survey approach, this study identified the underlying causes of late payments and release of retainage for electrical subcontractors, attempting to answer the questions, "What were the minimum, maximum and average delay days of final payment and release of retainage?", "What were the rank of factors in terms of significance on delaying final payment and release of retainage?", and "What were the rank of factors in terms of frequency on delaying final payment and release of retainage?" A survey questionnaire was developed and distributed to about 150 professionals in electrical subcontractors. 29 reports were collected. Based upon the analysis …


Small Strain Stiffness Of A Carbonatic Fine Grained Soil, Sulaiman Dawood Apr 2014

Small Strain Stiffness Of A Carbonatic Fine Grained Soil, Sulaiman Dawood

Open Access Theses

The work presented in this thesis is part of a broad effort aimed at the characterization of the engineering properties, microstructure and mineralogy of soft fine-grained carbonatic soil deposit in Southwestern Indiana (Daviess Co.). The specific focus of this thesis is the characterization, through both field and laboratory measurements, of the small strain behavior of this soil, commonly referred to as a "marl."

Index tests indicate that the 3.5 m marl layer present at the site is characterized by two soil types alternating in small sublayers: a high plasticity silt (soil M) with wn ∼60% and CaCO3 ∼60%, mostly in …


Detailed Finite Element Analysis And Preliminary Study Of The Effects Of Friction And Fastener Pre-Tension On The Mechanical Behavior Of Fastened Built-Up Members, Francisco Javier Bonachera Martin Apr 2014

Detailed Finite Element Analysis And Preliminary Study Of The Effects Of Friction And Fastener Pre-Tension On The Mechanical Behavior Of Fastened Built-Up Members, Francisco Javier Bonachera Martin

Open Access Theses

The characterization of fatigue resistance is one of the main concerns in structural engineering, a concern that is particularly important in the evaluation of existing bridge members designed or erected before the development of fatigue design provisions. The ability of a structural member to develop alternate load paths after the failure of a component is known as member-level or internal redundancy. In fastened built-up members, these alternate load paths are affected by the combination of fastener pre-tension and friction between the structural member components in contact. In this study, a finite element methodology to model and analyze riveted and bolted …


Graphical Performance Measures For Practitioners To Identify Split Failures, Richard Scott Freije Apr 2014

Graphical Performance Measures For Practitioners To Identify Split Failures, Richard Scott Freije

Open Access Theses

Detector occupancy is commonly used to measure traffic signal performance. Despite improvements in controller computational power, there have been relatively few innovations in occupancy-based performance measures or integration with other data. This thesis introduces and demonstrates the use of graphical performance measures based on detector occupancy ratios to verify potential split failures and other signal timing shortcomings reported to practitioners by the public. The proposed performance measures combine detector occupancy during the green interval, detector occupancy during the first five seconds of the red interval, and phase termination cause (gap out or force off). These are summarized by time of …


Dynamic Characteristic Identification Of Seismic-Excited Multi-Story Buildings Through Response-Only Technique, Agung Budipriyanto, Priyo Suprobo Apr 2014

Dynamic Characteristic Identification Of Seismic-Excited Multi-Story Buildings Through Response-Only Technique, Agung Budipriyanto, Priyo Suprobo

Makara Journal of Technology

Identifying dynamic characteristics of civil engineering structures is still a challenging task. It intends to assess behavior of the structures under time-dependent loads. This paper discusses a methodology suitable for identifying the characteristics of multi-story buildings using only their measured response under earthquake ground excitations. Appropriateness of technique used for structural identification was corroborated through coherence of the structure’s responses. The methodology was applied for identifying the characteristics of 14-story and 20-story office buildings located in a high seismic region. Responses of these two buildings recorded during three different seismic ground motions were investigated. The buildings’ response spectral densities and …


Synthesis And Characterization Of Soy-Based Polyurethane Foam With Utilization Of Ethylene Glycol In Polyol, Flora Elvistia Firdaus Apr 2014

Synthesis And Characterization Of Soy-Based Polyurethane Foam With Utilization Of Ethylene Glycol In Polyol, Flora Elvistia Firdaus

Makara Journal of Technology

The use of vegetable oils on replacing petroleum has attracted attention of many researchers. The chemical structure of vegetable oils are different from petrochemicals, so the structure of soybean oil has to be chemically modified through its unsaturated fatty acid chain in triglyceride. A two step process was conducted for the preparation of soy-polyol in designated temperatures; 50 °C, 60 °C, and 70 °C. Ethylene glycol (EG) as co-reagent was taking part in soy-polyol synthesis, and the soy-polyol was used as a sole polyol for polyurethane synthesis. Referred to the previous study, the existence of EG in polyurethane synthesis can …


Performances Of Free-Space Optical Communication System Over Strong Turbulence, Ucuk Darusalam, Purnomo Sidi Priambodo, Harry Sudibyo, Eko Tjipto Rahardjo Apr 2014

Performances Of Free-Space Optical Communication System Over Strong Turbulence, Ucuk Darusalam, Purnomo Sidi Priambodo, Harry Sudibyo, Eko Tjipto Rahardjo

Makara Journal of Technology

We report an experimental of free-space optical communication (FSOC) system that use tube propagation simulator (TPS) as the turbulence medium. The FSOC system use wavelength of 1550 nm at the rate transmission of 1000 Mbps and amplified with EDFA at the output of +23 dBm. Index structure of 10-15–10-13 as the representation of atmosphere index turbulences are used for simulation of intensity distribution model or scintillation. The simulation use gammagamma and K model as well. The beam wave propagation models used in simulation are plane wave, spherical wave and Gaussian wave. Spherical wave achieves highest performance via gamma-gamma in strong …


Preparations Of Nanostructured Silicide Bundles And Oxide Arrays, Hirokazu Tatsuoka, Wen Li, Erchao Meng, Daisuke Ishikwa, Kaito Nakane, Shingo Oda, Tomoji Matsushita, Natsuki Kurebayashi Apr 2014

Preparations Of Nanostructured Silicide Bundles And Oxide Arrays, Hirokazu Tatsuoka, Wen Li, Erchao Meng, Daisuke Ishikwa, Kaito Nakane, Shingo Oda, Tomoji Matsushita, Natsuki Kurebayashi

Makara Journal of Technology

A variety of nanostructured silicide bundles and oxide nanowire arrays with abundant, non-toxic materials we are prepared. The CrSi2 nanowire and Mg2Si/MgO composite nanowire bundles were synthesized using a Si substrate and a SiOx nanofiber bundle, respectively. The hexagonal MoSi2 nanosheet bundles were also synthesized using a MoS2 layered material as a template. In addition, ZnO, CuO/Cu2O and a-Fe2O3 nanowire arrays were prepared on semiconductor or metallic substrates. The growth phenomena and the structural properties of the nanostructured materials awere investigated. In addition, the preparations of axial and radial nanowire structures weare examined.


Bioethanol Production From Iles-Iles And Sorghum Starch As Raw Materials (Effect Of Cacl 2 Addition And Saccharification Time), Kusmiyati Kusmiyati, Ali Mahmudi Apr 2014

Bioethanol Production From Iles-Iles And Sorghum Starch As Raw Materials (Effect Of Cacl 2 Addition And Saccharification Time), Kusmiyati Kusmiyati, Ali Mahmudi

Makara Journal of Technology

Bioethanol produced from agricultural sources is one alternative energy that has been developed to substitute for petroleum. However, the use of food sources such as corn and cassava to produce bioethanol still face obstacles that lead to the scarcity of food and an increase in food prices. The aim of this study was to produce bioethanol from sorghum and iles-iles, which are not used by humans as food, especially in Indonesia. For both materials, the variables studied were saccharification time (4, 8, 24, and 48 h) and concentration of CaCl2 added to the liquefaction slurry (0, 100, 200, 300, and …


The Effect Of Zephyr Layer Orientation On Zephyrboard Made From Oil Palm Petiole, Lusita Wardani, Muhamad Yusram Massijaya, Yusuf Sudo Hadi, I Wayan Darmawan Apr 2014

The Effect Of Zephyr Layer Orientation On Zephyrboard Made From Oil Palm Petiole, Lusita Wardani, Muhamad Yusram Massijaya, Yusuf Sudo Hadi, I Wayan Darmawan

Makara Journal of Technology

It is very important to utilize oil palm petiole for the production of zephyr boards. This study aimed to analyze the effect of layer orientation on zephyr board quality. Zephyr boards were made with three coating patterns (A = cross perpendicular, B= combine A and C, and C= paralell) and five zephyr layers using urea formaldehyde adhesive. They were pressed for 20 min at a pressure of 25 kgf/cm² and a temperature 120 ºC, to a target density of 0.80 g/cm³ and a size of 300 mm X 300 mm X 12 mm. Our results showed that the physical and …


Performance Evaluation Of An Optimized Floating Breakwater In Oblique Waves With A Higher-Order Boundary Element Method, Faisal Mahmuddin, Masashi Kashiwagi Apr 2014

Performance Evaluation Of An Optimized Floating Breakwater In Oblique Waves With A Higher-Order Boundary Element Method, Faisal Mahmuddin, Masashi Kashiwagi

Makara Journal of Technology

In the previous study, the optimal performance of a two-dimensional (2D) floating breakwater shape was obtained. The performance of this shape was also confirmed with a model experiment in a towing tank. Moreover, the shape’s performance in three dimensions (3D) was investigated in a subsequent study. However, to predict the shape’s performance in a real application more accurately, the shape’s characteristics in oblique waves must also be evaluated. In this study, the performance and characteristics of the model (hydrodynamic forces, body motions, wave elevations, and drift forces) are computed using a higher-order boundary element method (HOBEM). The HOBEM, which is …


Stormwater Infrastructure Optimization On Conjunctive Improvements, Mohammad Hussin Shar Apr 2014

Stormwater Infrastructure Optimization On Conjunctive Improvements, Mohammad Hussin Shar

Civil & Environmental Engineering Theses & Dissertations

The studied drainage system is located in the downtown of the City of Newport News, in a basin known as Anderson Park. The drainage system collects and conveys rainfall runoffs to the system outfall located at the shoreline of the Hampton Roads body of water, which is located south of the study area. The aim of this study is to analyze the area's drainage system, determine maximum capacities, identify system deficiencies and generate the most possible, practical and economical solution for fixing the system deficiencies.

After collecting all of required data, the drainage system was modeled and calibrated using the …


Evaluation Of Hand Augered Well Technologies' Capacity To Improve Access To Water In Coastal Ng[Oumlaut]Be Communities In Panama, Sarah Hayman Mar 2014

Evaluation Of Hand Augered Well Technologies' Capacity To Improve Access To Water In Coastal Ng[Oumlaut]Be Communities In Panama, Sarah Hayman

USF Tampa Graduate Theses and Dissertations

Amid the global efforts surrounding United Nations' Millennium Development Goal Target 7c to improve access to safe and sustainable drinking water among populations who lack this resource, it has become essential to monitor and evaluate progress. Development initiatives working to achieve improved drinking water access often introduce appropriate technologies designed to be sustainably owned and operated by populations in rural areas suffering from water related hardships. It is valuable to thoroughly examine the degree to which these technologies satisfy intended objectives and affect user experienced water access. The accurate reflection of impact and progress can be complex, as the evaluation …


Experimental Study Of Soil Water Migration In Freezing Process, Xuesong Mao, Carol J. Miller, Zhongjie Hou, Abdul Khandker Mar 2014

Experimental Study Of Soil Water Migration In Freezing Process, Xuesong Mao, Carol J. Miller, Zhongjie Hou, Abdul Khandker

Civil and Environmental Engineering Faculty Research Publications

Soil water migration is a significant factor in the development of subgrade ice layers in permafrost areas. The prediction of moisture inflow to the freezing zone is an important element in the design and analysis of robust highway subgrade in permafrost regions. In order to better understand moisture inflow to the freezing zone, we designed an experimental investigation to monitor the variation of water content and temperature in freezing soil. Identical experiments were conducted using three different soil types: clay, silt, and fine sand. Moisture was supplied from the sample base while the column was maintained at a constant nonfreezing …


Road Safety Audits, Henry Brown Mar 2014

Road Safety Audits, Henry Brown

Purdue Road School

A Road Safety Audit (RSA) is a formal review of an existing or proposed road segment or intersection by an independent, multi-disciplinary team. The purpose of an RSA is to identify safety concerns and suggest possible countermeasures to the project owner. There are several benefits to conducting RSAs, including increased awareness of safety and a reduction in the number of crashes. The RSA process includes 8 steps during which the RSA team develops a list of findings and presents them to the project owner for consideration. The RSA process for an existing facility includes a field review during which the …


2014 Road School, Kevin M. Hetrick Mar 2014

2014 Road School, Kevin M. Hetrick

Purdue Road School

At the 2014 Road School, this presentation focused on the proposed sliding of the Milton-Madison Bridge, a 15000 ton truss superstructure intended to move laterally 55 feet from a temporary location onto permanent piers. The project was a joint procurement between INDOT and KYTC, with a Design/Build team consisting of Walsh Construction, Buckland and Taylor, and Burgess and Niple performing the slide. The presentation was in early March, with the slide scheduled for later in the month. The slide will be the largest of its kind.


Ada Prowag Status And Common Issues/Solutions, Stephen G. Metzer Aicp, Pws Mar 2014

Ada Prowag Status And Common Issues/Solutions, Stephen G. Metzer Aicp, Pws

Purdue Road School

The Proposed Accessibility Guidelines for Pedestrian facilities in the Public Right-of-Way (aka PROWAG), dated July 26, 2011, went through an extensive public comment period that ended in early 2012. The Access Board anticipates issuing final guidance that will be the enforceable standard for facilities in the public ROW. This presentation will provide the latest status of the guidelines and present common problems and creative solutions.


Most Common Errors For Ada Ramp Construction, Stephen G. Metzer Aicp, Pws Mar 2014

Most Common Errors For Ada Ramp Construction, Stephen G. Metzer Aicp, Pws

Purdue Road School

Curb ramps are essential for persons with disabilities to traverse pedestrian facilities, allowing them to get from street level to the sidewalk. Errors that occur during the construction of curb ramps can result in ramps that are non-compliant with the Americans with Disabilities Act (ADA) guidelines. This presentation will include examples of common sidewalk construction errors and offer ways that project engineers can assess existing ramps to identify cases where additional design assistance may be required.


I-65 South Split Continuously Reinforced Concrete Pavement, Tommy E. Nantung Mar 2014

I-65 South Split Continuously Reinforced Concrete Pavement, Tommy E. Nantung

Purdue Road School

Continuously reinforced concrete pavement (CRCP) is constructed with reinforcing steel placed in along the entire length of the pavement. CRCP forms tight transverse cracks to evenly transfer loads without the need of contraction joints. The result is a continuous, smooth-riding pavement surface capable of accommodating heavy traffic loads in a severe environmental condition. First constructed in Indiana more than 75 years ago on US-50, CRCP became popular with the construction of the Interstate Highway system in the 1960s and 1970s. Many sections of interstate and non-interstate highways constructed at that time are still in service today, having outperformed their original …