How ICT Surveying Is Transforming Civil Engineering! Benefits of Introducing Drones and Point Cloud Data and On-site Case Studies

At civil engineering construction sites, the introduction of ICT (information and communication technology) has dramatically changed surveying work. Aerial photogrammetry using drones, processing of point cloud data, and the utilization of three-dimensional models—digital technologies are complementing or replacing traditional surveying methods. These technologies have improved measurement efficiency and made it possible to obtain more detailed and accurate construction information. For practitioners, understanding the characteristics of ICT surveying and how to apply it on site is indispensable for enhancing competitiveness going forward. This article provides a detailed explanation of the benefits of introducing ICT surveying and specific field case studies.

Definition of ICT Surveying and Its Impact on the Field

ICT surveying is a general term for new surveying methods that utilize information and communication technology. These include aerial photogrammetry using drones, three-dimensional measurement using laser scanners, high-precision positioning using GNSS, and the use of point cloud data processing software. These technologies enable efficiencies and accuracy improvements that were not achievable with traditional surveying methods.

The impact of ICT surveying on civil engineering sites is wide-ranging. First, it shortens measurement time. Understanding the current conditions of large areas can now be completed in a matter of hours. Tasks that previously took days to weeks with traditional methods can be achieved in hours through drone surveying. Second, it improves measurement accuracy. Point cloud data contains millions of points and provides detailed information that conventional measurement methods cannot obtain. Third, it enhances safety. Surveys of hazardous locations can be performed with drones, reducing safety risks for workers.

At the same time, ICT surveying also has challenges. These include the high cost of equipment, the software and specialized expertise required for data processing, and compliance with legal regulations. It is important to understand these challenges and consider appropriate implementation methods tailored to site conditions.

Advantages and Applications of Drone Surveying

Aerial photogrammetry using drones is spreading most rapidly among ICT surveying methods. The reasons include lower equipment costs and that piloting skills have become easier to acquire. Drones come in several types, such as common multicopters, fixed-wing aircraft, and vertical takeoff and landing (VTOL) aircraft. Each type has its own characteristics and is selected according to the measurement target and the environment.

As advantages of drone surveying, the first is a wide field of view. By capturing images from altitude, you can grasp the overall picture, including areas not visible from the ground. It is used in a variety of situations such as investigating landslides, assessing disaster areas after floods, and checking progress on large-scale construction. Next is rapid information acquisition. The period from capture to processing is short, allowing the information needed for decision-making to be obtained quickly. Furthermore, safety is improved. Drones make it possible to survey dangerous places that humans cannot directly access, such as cliff tops and steep slopes.

Specific applications of drone surveying include, first, large-scale land development earthworks. It enables efficient assessment of current conditions and monitoring of construction progress across construction areas of several hundred hectares. Next is identifying the positions of existing structures in road-widening projects. By using drones to determine the locations of roadside buildings and utility poles, detour routes and construction methods can be planned accurately. Also, for forest road maintenance in mountainous areas, capturing complex terrain with drones improves design accuracy. In slope construction projects, the overall stability of slopes can be monitored dynamically.

Point Cloud Data Processing and Its Applications

Point cloud data consist of large sets of point information with three-dimensional coordinates obtained from laser scanners and drones. By processing this data, various outputs can be generated, such as topographic maps, orthophotos, and three-dimensional models of buildings. Point cloud processing software automatically performs these processes and provides the data required for preparing design documents and for construction management.

The greatest advantage of point cloud data is its level of detail. Subtle terrain variations that cannot be represented on conventional contour maps can be clearly captured by point cloud data. For example, detailed information can be obtained such as the location of mountain streams, the shape of slip surfaces on slopes, and the deterioration condition of existing structures. This information enables accurate decision-making during the design stage and strengthens quality control during the construction stage.

Specialized software is required to process point cloud data. Processing tasks include point cloud filtering (removal of unnecessary points), classification (ground, buildings, trees, etc.), and meshing (generating surfaces from points). To carry out these processes efficiently, not only software operation skills but also basic knowledge of surveying and design are necessary. Because work is often outsourced to external specialists, building a collaboration framework with contractors is important.

The Path to BIM/CIM Integration

BIM (Building Information Modeling) and CIM (Construction Information Modeling) are systems for integrating and managing information across an entire construction project using three-dimensional digital models. Data acquired through ICT surveying forms the foundation of these BIM and CIM systems. Consistent information management is realized from the design phase, through the construction phase, to the operation and maintenance phase after completion.

By introducing BIM and CIM, multiple stakeholders can refer to the same database. When designers, contractors, and construction managers view the same three-dimensional model, communication becomes smoother. Automatically performing clash detection (to check whether different structures overlap) reduces errors at the design stage. During the construction phase, importing as-built data into the three-dimensional model streamlines progress management and quality verification.

However, there are many challenges in implementing BIM and CIM. Creating and maintaining data is costly and requires cooperation from all stakeholders. Operating the software demands specialized skills, making workforce development indispensable. Integrating them with existing construction processes is also a challenge. Overcoming these issues requires organizational efforts and a long-term perspective.

Progress Management Using Unmanned Aerial Surveying

As a practical application of ICT surveying, there is construction progress management using unmanned aerial surveying. By processing images regularly captured by drones, construction progress can be quantified and visualized. For example, in land development works, drones can be flown monthly to capture images and monitor changes in earthwork volume. In road construction, changes in road geometry at each construction stage can be checked in three dimensions.

The advantage of using ICT surveying for progress management is that it makes management based on objective data possible. With conventional visual progress assessments, the evaluator’s subjectivity could influence the judgment. Because ICT surveying is based on numerical data, it enables more accurate grasp of progress. In addition, since progress delays can be detected early, countermeasures can be implemented quickly.

An imaging plan for progress management is also important. Capture frequency, capture altitude, capture coverage, and so on need to be appropriately set according to the characteristics of the construction work. Frequent captures provide abundant data but increase costs. Conversely, if the capture frequency is too low, important changes may be missed. It is important to establish an optimal imaging plan that takes into account the pace of construction progress and the level of issues that need to be detected.

Case Study 1: Large-scale Land Development Work

On earthworks projects on the scale of several hundred hectares, the benefits of ICT surveying are particularly significant. Pre-construction drone surveys allow the current topography of the entire construction area to be accurately captured. From the resulting point cloud data, precise earthwork volume calculations are performed and construction plans are developed. During construction, periodic drone imaging clarifies the status of each stage of work and verifies that construction is being carried out according to the design.

In this case, drone surveying enabled highly accurate earthwork volume management that was difficult to achieve with conventional methods. By accurately determining the fill volume at each stage of the construction, material procurement was optimized and costs were reduced. In addition, as a final check upon completion of construction, drone surveying confirmed that the finished terrain matched the design. Overall, the introduction of ICT surveying shortened the construction period and improved quality.

The lessons learned from this project include that thorough advance preparation is essential when introducing drone surveying. It is necessary to detail the imaging plan, establish a data-processing framework, and provide explanations and training to construction stakeholders. In addition, planning an imaging schedule that takes weather impacts into account is also important.

On-site Case Study 2: Safety Management for Slope Construction

When constructing structures on steep slopes, safety management is the highest priority. Traditionally, on-site visual checks were the primary method, but the introduction of ICT surveying has enabled more detailed and safer management. By regularly photographing with drones, changes in the slope can be monitored dynamically. The progression of cracks and movements of retaining walls can be recorded in detail.

In this case, we quantified the slope deformation in three dimensions from point cloud data obtained by drone photography. Even small deformations could be detected, and risk assessments during the construction phase became more accurate. Because signs of slope instability can be detected early, safety measures can be taken in advance. By continuing drone photography even after construction is completed, long-term stability can be monitored.

A key aspect of this project was that the analysis of point cloud data required specialized expertise. Accurate interpretation of the data demanded knowledge of geotechnical engineering and structural mechanics. In addition, the regularity of drone imaging was important. Monthly imaging allowed trends in changes to be identified and made future predictions possible.

Case Study 3: Investigation of Deterioration of Existing Structures

In deterioration surveys of existing structures such as bridges and tunnels, conventional practice relied on manual inspections and simple measurements. The introduction of ICT surveying has enabled more detailed and accurate assessment of deterioration. From point cloud data acquired by laser scanners, crack patterns on concrete surfaces can also be automatically recognized.

In this case, a laser scanner was used to measure the bridge substructure, and the resulting point cloud data were used to quantitatively evaluate the inclination of the piers and the settlement of the foundations. Fine deterioration that went unnoticed with conventional measurement methods was also detected through analysis of the point cloud data. This information directly informed the design of the rehabilitation work, enabling more effective countermeasures to be implemented.

One lesson learned from this project is that comparison with past measurement data is important for the measurement of existing structures. Comparing point cloud data from multiple time periods makes trends of change clearer. Also, interpreting the numerical values obtained from point cloud data requires deep knowledge of the structure.

Challenges and Responses to Digitalization

While the introduction of ICT surveying brings many benefits, it also gives rise to new challenges. First, there is the complexity of data management. Storing and managing large volumes of point cloud data and drone imagery requires the establishment of an IT infrastructure. Second, there is the issue of security. It is necessary to address leaks and hacking of digital data, including construction information. Third, there is a shortage of personnel. There are not enough specialists in point cloud data processing and drone operation, and in many cases organizations have no choice but to rely on outsourcing.

Addressing these challenges requires a systematic organizational effort. This includes strengthening the IT department, establishing security policies, and building a human resources development framework. In addition, information sharing with industry peers and cooperation through consortia are effective. Utilizing public training programs is also an important means of human resource development.

Future Developments in ICT Surveying

In the field of ICT surveying, the use of AI (artificial intelligence) is progressing. AI technologies are being developed that automatically recognize specific features from point cloud data and automatically assess the degree of deterioration. If these technologies are put into practical use, the processing time for point cloud data will be greatly reduced, allowing ICT surveying to be implemented in a larger number of projects.

Also, by implementing real-time data processing, processing results can be obtained immediately after drone imaging. This enables faster construction decision-making. Furthermore, by combining this with AR (augmented reality) technology, it will also become possible to perform construction management directly on-site while viewing three-dimensional models.

With the emergence of these new technologies, the methods for surveying and managing civil engineering works are expected to change even more significantly in the future. iPhone-mounted GNSS high-precision positioning devices such as LRTK are also part of this technological evolution. Technologies that transform smartphones into high-precision positioning devices mean that high-precision surveying will become easily achievable at more job sites. Applications of these new surveying technologies are anticipated in various situations, such as verification of point cloud data obtained from drone surveys and detailed point measurements for construction progress management. By combining ICT surveying with these new technologies, the quality and efficiency of civil engineering works will continue to improve.

Data Security and Privacy Protection

With the introduction of ICT surveying, large amounts of digital data will be generated, stored, and shared. These data include site location information, construction status, and even information about the surrounding environment. If such data are misused, security problems may arise.

To protect data, measures such as encryption, access control, and regular security audits are necessary. When storing data in the cloud, it is important to verify the security level of the data center and choose an appropriate service provider. In addition, compliance with laws regarding the protection of personal information is also important as a corporate social responsibility.

Security training for staff is also essential. Ensuring that all staff acquire basic security literacy, such as password management, measures against phishing scams, and proper handling of data, improves the organization's overall security level.

The Path to BIM–CIM Integration and Future Developments

BIM (Building Information Modeling) and CIM (Construction Information Modeling) are systems for integrating and managing information for an entire construction project using three-dimensional digital models. Data acquired by ICT surveying forms the basis of these BIM and CIM systems. Consistent information management is realized from the design stage through the construction stage to post-completion maintenance. By introducing BIM and CIM, multiple stakeholders can reference the same database. When designers, contractors, and construction managers view the same three-dimensional model, communication becomes smoother. Automatically performing clash detection (checking whether different structures overlap) can reduce errors during the design stage. During construction, incorporating as-built data into the three-dimensional model streamlines progress management and quality verification. However, there are many challenges to implementing BIM and CIM. Creating and maintaining the data is costly and requires cooperation from all stakeholders. Operating the software requires specialized skills, making workforce development indispensable. Integrating them with existing construction processes is also a challenge. Overcoming these challenges requires organizational initiatives and a long-term perspective. In future civil engineering projects, hybrid measurement methods that combine multiple technologies are expected to become mainstream.

Progress Management and On-site Application Using Unmanned Aerial Surveying

A practical application of ICT surveying is construction progress management using unmanned aerial surveying. By processing images periodically captured by drones, construction progress can be quantified and visualized. The advantage of using ICT surveying for progress management is that it enables management based on objective data. Traditional visual assessments of progress involve the assessor's subjectivity, but because ICT surveying is based on numerical data, it enables a more accurate understanding of progress.

A phased approach to implementing ICT surveying

When introducing ICT surveying, it is more effective to take a phased approach rather than aiming for immediate full-scale implementation. First, trial ICT surveying in a small-scale pilot project to understand the method’s effectiveness and challenges before proceeding with full deployment; this approach minimizes the risk of failure. In the pilot project, it is important to run the conventional and new methods in parallel and carry out comparative verification in terms of accuracy and efficiency. The insights gained through such a validation process become valuable assets when promoting company-wide implementation later.

Actual Changes at Job Sites Resulting from the Introduction of ICT Surveying

The introduction of ICT surveying will dramatically change on-site work practices. Measurement tasks that previously involved many workers will be carried out more efficiently by a smaller team. At the same time, the process from data acquisition to processing and reporting to stakeholders will be shortened, enabling faster decision-making. Because construction stakeholders can monitor progress in real time, issues can be identified and addressed early. These improvements will enhance overall project quality while shortening schedules and cutting costs. ICT surveying is not merely a technical evolution but an innovative initiative that transforms how civil engineering construction is carried out.