Yong K. Cho

Georgia Institute of Technology | GT · School of Civil & Environmental Engineering

Since hydration heat generated during construction has been the cause of cracking and deformations in mass concrete structures, selecting appropriate thermal control plans is crucial in mass concrete construction. However, developing numerical models to predict the heat of hydration in mass concrete involves complex processes that demand extensive...

Thermal management of mass concrete can adversely impact a project’s cost and schedule, both during planning and in execution. Nomograms are presented as aids to quickly identifying and making tradeoffs among promising thermal management options. First, the temperature of fresh concrete and a worst-case adiabatic temperature estimate is provided by...

The temperature and time-dependent heat of hydration of cementitious pastes is a fundamental property to understand concrete performance. Cement hydration can be depicted using kinetic models by considering the effect of the chemical and physical properties of the cementitious pastes and the curing conditions. Supplementary cementitious materials a...

The durability of massive concrete structures may be compromised by delayed ettringite formation and thermal cracking. Designers have sought to develop alternative mix designs to control these durability issues, the efficacy of which depends on the adiabatic temperature rise of the mixtures. This contribution introduces a methodology for the predic...

Planning, monitoring, and maintenance of highway assets is an essential, long-term operation for successful civil infrastructure management. These monitoring and maintenance activities are usually carried out manually, suffering from time-consuming, costly, potentially dangerous tasks. The advancements in Unmanned Aerial Vehicles (UAVs) and compute...

After the COVID-19 outbreak, a new concept of building maintenance (BM) systems is needed because current approaches highly rely on physical contact between workers, engineers, and managers. It imposes health and safety risks as increasing concerns about infections and spreads. This adds burdens to take unavoidable close contact and health risks to...

Building Information Modeling (BIM) technology is a key component of modern construction engineering and project management workflows. As-is BIM models that represent the spatial reality of a project site can offer crucial information to stakeholders for construction progress monitoring, error checking, and building maintenance purposes. Geometric...

Since point clouds have reality measurements of physical objects, they are often used to reconstruct the as-built 3D model of building construction sites through a modeling process called Scan-to-BIM. However, the reality measurements in point cloud data, such as actual color and deformed shapes of the original objects, could disappear during the s...

Purpose The study seeks to identify the impact of variables in a deep learning-based bankruptcy prediction model, which has achieved superior performance to other prediction models but cannot easily interpret hidden processes. Design/methodology/approach This study developed three LSTM-RNN–based models that predicted the probability of bankruptcy...

In monitoring disaster sites, mobile robots represent a fast, reliable, and practical option to remotely inspect active areas in disaster management for applications such as risk management, search and rescue, and structural assessment purposes. Mobile robots can efficiently collect laser scan data and reconstruct the state of ongoing disaster reli...

Highway maintenance and infrastructure monitoring tasks often involve labor-intensive activities and long inspection times. Examples of these maintenance tasks include landscaping and lawn care, detecting damaged road segments, and identifying missing road signs. While several infrastructure monitoring methods have been proposed, many of them are o...

The state-of-the-art in construction material classification has used various machine learning approaches using 2D color image datasets. However, construction materials are often discolored due to other foreign substances and lighting conditions, making it challenging to classify construction materials only with color information. To address this p...

In the long-term operation of highway infrastructure, timely monitoring and performance verification of maintenance tasks are integral. Some examples of these maintenance tasks are mowing the landscape of highway areas, detecting debris, patching unfilled holes in the pavement, and identifying and repairing road signs. This study will develop a fra...

The special collection of papers on Information Technology and the 12 Built Environment is available in the ASCE Library (https:// 13 ascelibrary.org/jcemd4/it_and_built_environment) 14 In the recent decade, information technology (IT), including 15 computing, communication, and sensing technology, has advanced 16 extensively and radically transfor...

Emerging technologies play an essential role in improving overall productivity in the construction industry. However, this field has historically been criticized for the slow adoption of these innovative tools. To promote emerging technology adoption, exchanging knowledge and practices through academia and industry collaboration is essential. This...

Crane operators are often unable to identify collision hazards due to limited visibility during blind lifts or when operating under cluttered conditions. This paper presents a multisensor-driven real-time crane monitoring system consisting of load tracking, obstacle detection, worker detection, collision warning, and 3D visualization modules. A com...

3D point cloud segmentation is an important function that helps robots understand the layout of their surrounding environment and perform tasks such as grasping objects, avoiding obstacles, and finding landmarks. Current segmentation methods are mostly class-specific, many of which are tuned to work with specific object categories and may not be ge...

3D point cloud segmentation is an important function that helps robots understand the layout of their surrounding environment and perform tasks such as grasping objects, avoiding obstacles, and finding landmarks. Current segmentation methods are mostly class-specific, many of which are tuned to work with specific object categories and may not be ge...

With the increasing interest in mobile robots for construction applications, autonomous navigation in unstructured and uneven construction sites has become a critical challenge. To ensure the safe and robust navigation of a robot in such environments, this study develops an optimal obstacle-avoiding path planner for stable posture (OOPS) that minim...

Cranes are associated with high levels of accidents and struck-by fatalities in many industrial settings. This is due to the congested nature of crane operation sites and the high cognitive load for the crane operator to track the load position throughout the lifting operation, especially during blind lifts. Current research on crane safety assista...

In order to teleoperate excavators remotely, human operators need accurate information of the robot workspace to carry out manipulation tasks accurately and efficiently. Current visualization methods only allow for limited depth perception and situational awareness for the human operator, leading to high cognitive load when operating the robot in c...

Monitoring and understanding construction workers' behavior and working conditions are essential to achieve success in construction projects. The dynamic nature of construction sites has heightened the awareness of the need for improved monitoring of the individual workers on the sites. Although several studies have shown promising results in autom...

Collecting 3D point cloud data of buildings is important for many applications such as urban mapping, renovation, preservation, and energy simulation. However, laser-scanned point clouds are often difficult to analyze, visualize, and interpret due to incompletely scanned building facades caused by numerous sources of defects such as noise, occlusio...

Road networks, especially those built in an extreme environment, are at risk of service failure after long-term exposure to various types of disruptive events. With growing costs of service failure, it has become increasingly important to evaluate the dynamic operability characteristics, i.e., the dynamic resilience, of road networks. However, exis...

3D as-damaged models of a disaster site can be reconstructed from LiDAR scans by analyzing the point cloud data for indicators of damage such as cracks. Conventional methods for crack detection have limitations in terms of robustness or requiring a large training database. To achieve the goal of structural damage detection that can be used to recon...

3D point cloud data can be utilized for site inspection and reverse engineering of building models. However, conventional methods for building element retrieval require a database of 3D CAD or BIM models which are unsuitable for the case of historical buildings without as-planned models or temporary structures that are not in the pre-built model. T...

The construction of buildings and infrastructure systems increasingly rely on the extensive use of cranes to transport and erect large and heavy components and modules. Although modern cranes are equipped with various sensors and on-board computers to detect overloading and overturning, crane operators primarily rely on their own experience and kno...

The use of remote excavators for disaster relief is preferable to the use of human relief workers. These autonomous systems are subject to inherent flexibility in their bases. Motion of the upper mechanisms of these systems induce oscillations in the base which feed through the manipulator system. To damp these oscillations the posture of the manip...

Point clouds constitute a high fidelity representation of the 3D geometry of physical objects; thus, point cloud technology is often used to create an as-built building information modeling (BIM) of a building construction site. However, the conventional Scan-to-BIM pipeline still requires significant time and manual efforts to complete. To address...

Construction tasks involve various activities composed of one or more body motions. As construction projects are labor-intensive and heavily rely on manual tasks, understanding the ever-changing behavior and activities is essential to manage construction workers effectively regarding their safety and productivity. While several research efforts hav...

Night-time surveillance is important for safety and security purposes. For this reason, several studies have attempted to automatically detect people intruding into restricted areas by using infrared cameras. However, detecting people from infrared CCTV (closed-circuit television) is challenging because they are usually installed in overhead locati...

In the construction industry, predicting business failure and providing early warnings are critical challenges in the prevention of business failure chain reactions. Most relevant studies have developed models that predicted the probability of business failure within 1 year using financial ratios. Although a few studies have attempted to use nonfin...

Predicting business failure of construction contractors is critical for both contractors themselves and other stakeholders such as project owners, surety underwriters, investors and government entities. In an attempt to identify a new model with better prediction of business failure of the construction contractors, this study utilized long short-te...

Publisher’s Note: This paper was selected for publication in ASME Letters in Dynamic Systems and Control. https://www.asmedigitalcollection.asme.org/lettersdynsys/article/doi/10.1115/1.4046684/1081845/Configuration-Optimization-for-End-Point

Mobile robots play an important role in search and rescue operations in post-disaster scenarios such as earthquakes and hurricanes due to the hazardous nature of these sites. Mobile robots can use Lidar devices to scan affected infrastructure and identify the hazard level of different buildings on the disaster site. This research proposes a method...

This paper discusses enabling autonomous mobile robots to operate in unstructured terrain and environments and gather data in a time-efficient manner. In rugged environments such as construction sites and disaster sites, spatiotemporal data is difficult to acquire since these environments are potentially hazardous to humans. Autonomous robot system...

Laser scanning of built infrastructure is an integral process in construction management for accurate progress estimation, deviation detection, and asset tracking. Raw data from laser-scanned point clouds can be converted into portable, semantically-rich formats in a process known as Scan-to-BIM (Building Information Model). Manual annotation for p...

Due to the characteristics of the construction projects, construction contractors are often vulnerable to business failure compared to those in other industries. Thus, predicting the potential business failure of construction contractors has been a crucialissue. This study proposes a model that predicts business failure using Long Short Term Memory...

Nuclear power plant disasters in the past century have led to the major economic loss, negative environmental impact, and danger to human lives. Disaster relief operations such as search and rescue, hazard detection, and damage assessment face significant challenges due to the difficulty in categorizing and analyzing damaged building structures. Th...

Construction tasks involve various activities composed of one or more body motions. It is essential to understand the dynamically changing behavior and state of construction workers to manage construction workers effectively with regards to their safety and productivity. While several research efforts have shown promising results in activity recogn...

A robotic teleoperation system of excavator has been developed to improve safety and remote-control methods at hazardous situations such as construction or disaster sites. This paper introduces an innovative remote-control method and a newly developed robotic hardware system, Phantom, to rapidly retrofit existing construction equipment for efficien...

Nuclear power plant accidents such as those at Fukushima and Chernobyl release a significant amount of hazardous radiation. It takes a long time to recover from such an accident and the difficulty of the task is very high due to the many risks. Restoration work using unmanned vehicles protects workers from the risk of secondary accidents such as ra...

The primary advantages of utilizing a mobile robot, Unmanned Ground Vehicle (UGV), are its autonomous navigation and data collection capabilities from a large-scale environment. However, the UGV is restricted by its limited perception ability in a cluttered environment. To address this limitation, an Unmanned Aerial Vehicle (UAV) can cooperate with...

Technology plays an essential role in accelerating and improving various construction processes, so both academia and industry have interest in adopting and adapting technologies in their research or projects. In this respect, academic and industry collaboration has increasingly become essential in the construction industry. A critical step for aca...

Technology plays an essential role in accelerating and improving various construction processes, so both academia and industry have interest in adopting and adapting technologies in their research or projects. In this respect, academic and industry collaboration has increasingly become essential in the construction industry. A critical step for aca...

Nuclear power plant accidents such as those at Fukushima and Chernobyl release a significant amount of hazardous radiation. It takes a long time to recover from such an accident and the difficulty of the task is very high due to the many risks. Restoration work using unmanned vehicles protects workers from the risk of secondary accidents such as ra...

The primary advantages of utilizing a mobile robot, unmanned ground vehicle (UGV), are its autonomous navigation and data collection capabilities from a large-scale environment. However, the UGV is restricted by its limited perception ability in a cluttered environment. To address this limitation, an unmanned aerial vehicle (UAV) can cooperate with...

A robotic teleoperation system of excavator has been developed to improve safety and remote-control methods at hazardous situations such as construction or disaster sites. This paper introduces an innovative remote-control method and a newly developed robotic hardware system, Phantom, to rapidly retrofit existing construction equipment for efficien...

Construction tasks involve various activities composed of one or more body motions. It is essential to understand the dynamically changing behavior and state of construction workers to manage construction workers effectively with regards to their safety and productivity. While several research efforts have shown promising results in activity recogn...

The characteristics of dynamic construction sites increase the difficulty of collecting the high-quality geometric data necessary to achieve construction management activities. This paper introduces a new autonomous framework for 3D geometric data collection in a dynamic cluttered environment using an unmanned ground vehicle (UGV) and an unmanned a...

Construction progress estimation is an essential component of the daily construction cycle to ensure high productivity and quality. However, using laser-scanned point clouds for the purpose of measuring the deviation between the as-built structures and the as-planned Building Information Model (BIM) remains cumbersome due to the difficulty in data...

The objective of this research is to characterize the heat generation in mass concrete placements typically encountered by GDOT in its construction projects, to create an analytical method for determining the cooling requirements for mass concrete, and to develop a comprehensive guideline for transportation infrastructure applications. This guideli...

Automatically registering 3D point clouds generated by unmanned aerial and ground vehicles (UAVs and UGVs) is challenging, as data is acquired at different locations with different sensors, consequently resulting in different spatial scales and occlusions. To address these problems, this study proposes a framework for the automated registration of...

Mobile robots need to create high-definition 3D maps of the environment for applications such as remote surveillance and infrastructure mapping. Accurate semantic processing of the acquired 3D point cloud is critical for allowing the robot to obtain a high-level understanding of the surrounding objects and perform context-aware decision making. Exi...

Scaffolds are frequently used in construction projects and significantly impact safety and productivity. However, in many construction projects, the decisions on scaffolds are often made without thorough spatiotemporal analyses considering the impact of the scaffolds on safety. Even with the recent advancements in Building Information Modeling (BIM...

Crane lift operations are human-centric tasks where lift safety heavily relies on the operator's awareness of potential spatial constraints and associated safety risks. Blind lifts on congested offshore platform (OP) environments, therefore, are inherently dangerous because of substantial presence of spatial conflicts in the crane workspace and the...

Unmanned aerial/ground vehicles (UAV/UGV) can be a useful means of obtaining 3D geographic data of complex construction sites because of their superior advantages of site accessibility and remote controllability. However, both technologies have individual disadvantages caused by their limited field of view. Especially, the accuracy of vertical elem...

Over the last decade, researchers have explored various technologies and methodologies to enhance worker safety at construction sites. The use of advanced sensing technologies mainly has focused on detecting and warning about safety issues by directly relying on the detection capabilities of these technologies. Until now, very little research has e...

Over the last decade, researchers have improved passive regulations for construction site safety. Despite these passive regulations, occupational fatalities frequently occur. To overcome the limitations of passive regulations, researchers have devoted a great deal of effort to developing active sensing and alert systems that triggers an alarm at a...

Scaffolds are frequently used in construction projects and significantly impact safety and productivity. However, in many construction projects, the decisions on scaffolds are often made without thorough spatiotemporal analyses considering the impact of the scaffolds on safety. Even with the recent advancements in building information modeling (BIM...

Crane lift operations are human-centric tasks where lift safety heavily relies on the operator’s awareness of potential spatial constraints and associated safety risks. Blind lifts on congested offshore platform (OP) environments, therefore, are inherently dangerous because of the substantial presence of spatial conflicts in the crane workspace and...

Because the methods used to compute the live load distribution for moment and shear force in modern highway bridges subjected to vehicle loading are generally constrained by their range of applicability, refined analysis methods are necessary when this range is exceeded or new materials are used. This study developed a simplified method to calculat...

Temporary structures are essential to support various activities of a construction project. Proper utilization of temporary structures can have a significant influence on critical aspects of the project such as cost, productivity, and safety. However, a process of planning temporary structures still relies on labor-intensive and error-prone efforts...

Laser scanning is one of the most accurate methods of measuring the geometric accuracy of the as-built condition of a construction site. However, using laser-scanned point clouds for the purpose of measuring the deviation between the as-built structures and the as-planned Building Information Model (BIM) remains cumbersome due to the difficulty in...

With the rapid advancement of laser scanning and photogrammetry technologies, frequent geometric data collection at construction sites by contractors has been increased for the purpose of improving constructability, productivity, and onsite safety. However, the conventional static laser scanning method suffers from operational limitations due to th...

Search-and-rescue (SAR) robots operating in post-disaster urban areas need to accurately identify physical site information to perform navigation, mapping and manipulation tasks. This can be achieved by acquiring a 3D point cloud of the environment and performing object recognition from the point cloud data. However, this task is complicated by the...