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Full-Text Articles in Construction Engineering and Management

Influence Of Foundation Damping On Offshore Wind Turbine Monopile Design Loads, Wystan Carswell, Sanjay R. Arwade, Jörgen Johansson, Don J. Degroot Jan 2022

Influence Of Foundation Damping On Offshore Wind Turbine Monopile Design Loads, Wystan Carswell, Sanjay R. Arwade, Jörgen Johansson, Don J. Degroot

Publications

The dynamic behavior of offshore wind turbines (OWTs) must be designed considering stochastic load amplitudes and frequencies from waves and mechanical loads associated with the spinning rotor during power production. The proximity of the OWT natural frequency to excitation frequencies combined with low damping necessitates a thorough analysis of sources of damping; of these sources of damping, least is known about the contributions of damping from soil-structure interaction (foundation damping). This paper studies the influence of foundation damping on cyclic load demand for monopile-supported OWTs considering the design situations of power production, emergency shutdown, and parked conditions. The NREL 5 …


Reduction Of Structural Damage From The Thermal Expansion Of Concrete Using Multifunctional Materials, Darren Hartl, Mirmilad Mirsayar Oct 2019

Reduction Of Structural Damage From The Thermal Expansion Of Concrete Using Multifunctional Materials, Darren Hartl, Mirmilad Mirsayar

Publications

This study leveraged past successes in the analysis and design of shape memory alloy (SMA) components to address the issue of thermal expansion in concrete structures. Since the SMA used in the current work is relatively cheaper than other common SMAs (less than $50/lb compared to NiTi which is $200/lb due to difficulties in processing), it is anticipated that the findings of the study could be implemented in real infrastructures made of concrete, asphalt concrete, and other complex large infrastructure. Low-cost Fe-SMAs and other multifunctional materials can be considered as a replacement for components made of steel (e.g., in reinforced …


Soil-Recycled Aggregate-Geopolymer Road Base/Subbase Mixtures: Steps Towards Sustainability, Mohammad Khattak, Daniel Odion Oct 2019

Soil-Recycled Aggregate-Geopolymer Road Base/Subbase Mixtures: Steps Towards Sustainability, Mohammad Khattak, Daniel Odion

Publications

This study deals with the development of Soil-Geopolymer mixtures using flyash, alkali activator and recycled aggregates (RAG) including recycled concrete (RCA) and reclaimed asphalt (RAP) as an alternative to soil-cement for pavement base and subbase layers. Several mix constituents were varied such as flyash type and content, RCA and RAP content and ratio of sodium silicate and sodium hydroxide. Experiment design was established and mechanical and durability characteristics of Soil-RAG-Geopolymer mixtures were evaluated and then compared to the conventional soil-cement mixtures. The results of the testing showed that for the selected Soil-RAG-Geopolymer mixtures the strength, stiffness, permanent deformation, and durability …


Development Of Geopolymer-Based Cement And Soil Stabilizers For Transportation Infrastructure, Miladin Radovic, Anand Puppala Sep 2019

Development Of Geopolymer-Based Cement And Soil Stabilizers For Transportation Infrastructure, Miladin Radovic, Anand Puppala

Publications

Geopolymer Cement (GPC) has drawn much attention in the recent years as an alternative to Ordinary Portland Cement (OPC) for soil stabilization, pavements, bridges and other transportation structures due to their good mechanical properties in comparison to OPC. In addition, GPC can be processed at room temperatures from aqueous solutions of waste materials (e.g. fly ash) or abundant natural sources (e.g. clay), thereby significantly reducing CO2 production associated with processing of OPC. As such, GPC proves to be a more sustainable and environmentally friendly alternative than OPC. This research explores methods to develop GPC with desired properties and evaluate their …


Mitigating Reflective Cracking Through The Use Of A Ductile Concrete Interlayer, Qian Zhang, Mohammad Khattak, Adway Das Sep 2019

Mitigating Reflective Cracking Through The Use Of A Ductile Concrete Interlayer, Qian Zhang, Mohammad Khattak, Adway Das

Publications

Reflective cracking is considered one of the most important issues that causes premature deterioration of composite pavements. Many types of mitigation methods have been studied in the past. However, they are either not effective in delaying the reflective cracking, or they only extend the service life by a few years. To address this critical issue and significantly extend the service life of the composite pavement, in this research, a ductile interlayer made of engineered cementitious composites (ECC) was proposed. It was hypothesized that by adding a thin layer of highly ductile ECC material between the existing pavement and overlay, reflective …


Development Of Metals Corrosion Maps Of Arkansas And Maintenance Of Cross-Drains, Zahid Hossain, Ashraf Elsayed, Mdariful Hasan Aug 2019

Development Of Metals Corrosion Maps Of Arkansas And Maintenance Of Cross-Drains, Zahid Hossain, Ashraf Elsayed, Mdariful Hasan

Publications

Corrosion potential of metallic structures in alluvial soils is governed by chemical and electromagnetic properties of the soils. Geotechnical engineers are generally more concerned about different types of soils and their physical and mechanical properties than the chemical aspects. The main objective of this study is to analyze the geotechnical, electrochemical and electromagnetic properties of soils in Arkansas. Important parameters (e.g., soil resistivity) related to corrosion potential of metal culverts have been predicted through neural network (NN) models. The developed NN models have been trained and verified by using laboratory test results of soil samples collected from Arkansas Department of …


Decision-Making Tool For Road Preventive Maintenance Using Vehicle Vibration Data, Changbum Ahn, Chao Wang, Jing Du Aug 2019

Decision-Making Tool For Road Preventive Maintenance Using Vehicle Vibration Data, Changbum Ahn, Chao Wang, Jing Du

Publications

Automated and timely road pavement damage inspection is critical to the preventive maintenance and the long-term sustainability and resilience of roads in Region 6. Current road inspection practices rely heavily on a manual process. Sensor-based methods (e.g., LiDAR scanning) are promising but can be too expensive for a wider adoption. This study employs a crowdsourcing approach of using the vibration patterns of regular vehicles in inferring specific types of road damages. A cloud-based smart phone app and system was developed to collect real-time vehicle vibrations, location data, and road damage images for training the detection model. However, there is a …


A Comprehensive Framework For Life-Cycle Cost Assessment Of Reinforced Concrete Bridge Decks, Mohamed Soliman, Samir Ahmed, Ligang Shen Aug 2019

A Comprehensive Framework For Life-Cycle Cost Assessment Of Reinforced Concrete Bridge Decks, Mohamed Soliman, Samir Ahmed, Ligang Shen

Publications

Various environmental and mechanical stressors cause deterioration of concrete bridge decks. Normal wear and tear, freeze and thaw cycles, and chloride penetration due to deicing salts can cause aggressive deterioration that usually require frequent interventions during the life-cycle of the bridge. These interventions include deck maintenance and repairs (e.g., application of sealers or overlay placement) as well as bridge deck replacement. The quantification of the life-cycle cost of bridge decks considering maintenance and repair activities represents a significant challenge facing local and state transportation agencies. The life-cycle maintenance activities not only increase the direct life-cycle cost of the bridge, but …


Strategies For Prioritizing Needs For Accelerated Construction After Hazard Events, Fernando Moreu, Chao Wang, Xinxing Yuan, Laleh Ghanbari, Claudia Garrido Aug 2019

Strategies For Prioritizing Needs For Accelerated Construction After Hazard Events, Fernando Moreu, Chao Wang, Xinxing Yuan, Laleh Ghanbari, Claudia Garrido

Publications

There is a need for rapid and responsive infrastructure repair and construction after natural disaster events such as hurricanes, wildfires, and tornadoes. These natural disasters often shut down basic infrastructure systems, as experienced recently in several Region 6 states as well as in other states around the country. Accelerated construction practices are often used in these situations to speed up the traditional, and often slow, project delivery process. However, after a natural disaster, several and different types of transportation infrastructure components are in need of inspection, rehabilitation or reconstruction, and transportation agencies are challenged with the task of prioritizing these …


In-Situ Mechanical Characterization For Compacted Aggregates, Douglas Cortes, Paola Bandini Oct 2018

In-Situ Mechanical Characterization For Compacted Aggregates, Douglas Cortes, Paola Bandini

Publications

The evaluation of compacted unbound aggregate layers is perhaps the most common undertaking in transportation-related projects. The assessment of compaction compliance in engineered fills, subgrades, subbases, and bases in roadways and railways is central to ensure longevity of ground transportation infrastructure. In many cases, premature failures in roadways that originate in the unbound aggregate layers can be traced back to inadequate compaction. These failures are preventable, provided the problem areas can be identified by a suitable field test during construction. The most widely used method for compaction assessment during construction is the nuclear density gauge (NDG) test. While the device …