Civil Engineering Commons^™

Selected Durability Studies Of Geopolymer Concrete With Respect To Carbonation, Elevated Temperature, And Microbial Induced Corrosion, Mohammad Sufian Badar

Doctoral Dissertations

This thesis reports a comprehensive study related to the experimental evaluation of carbonation in reinforced geopolymer concrete, the evaluation of geopolymer concretes at elevated temperature, and the resistance of geopolymer concrete to microbial induced corrosion (MIC).

Carbonation: Reinforced concretes, made of geopolymer, prepared from two class F fly ashes and one class C fly ash, were subjected to accelerated carbonation treatment for a period of 450 days. Electrochemical, microstructure and pore structure examinations were performed to evaluate the effect of corrosion caused due to carbonation. GPC specimens prepared from class F fly ash exhibited lower corrosion rates by a factor …

Increasing The Supply Of Affordable Housing In Urban India - Mumbai, Upasna Viswanathan

Open Access Theses

The need for housing in today's world is irrefutable. The growing population, accompanied with the fast pace of urbanization, are producing great housing demand, in urban areas in particular. This study focused on one segment of housing - affordable housing, in Mumbai, India, the demand for which has been on a steady rise over the past decade. Though traditionally the State was the provider of affordable housing, private sector has been increasingly involved in the segment, beginning the economic meltdown of 2008-2009. Yet there is a huge demand-supply gap that exists, which needs to be filled. The researcher looks at …

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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 …