Revolutionizing Construction Sites with i-Construction! How Surveying DX Opens the Future of Construction

Definition and Purpose of i-Construction (Transforming the Construction Industry through DX)

i-Construction is a productivity improvement project for construction sites [started by the Ministry of Land, Infrastructure, Transport and Tourism in 2016](https://www.kkr.mlit.go.jp/toyooka/bimcim/03_whaticonstruction.html). It refers to an initiative to fully introduce ICT (information and communication technology) across the entire construction production process—from surveying and measurement through design, construction, inspection, and maintenance—to dramatically raise productivity at construction sites. The initiative is driven by labor shortages in the construction industry due to an aging and declining population and by challenging working conditions often described as the “three K’s” (kitsui, kitanai, kiken: tough, dirty, dangerous). The government has set a goal of improving on-site productivity by 20% by FY2025 through promotion of i-Construction, advancing policies around three pillars: ICT utilization, standardization of specifications, and leveling of construction schedules.

The purpose of i-Construction is to use digital technologies to raise productivity in the construction industry while simultaneously improving working conditions. By introducing ICT to increase per-person work efficiency, companies can strengthen their management base and translate those gains into higher wages and improved safety for workers. For example, automating or remotely controlling construction machinery to eliminate the need for humans to perform dangerous tasks and transforming construction sites into safe, attractive workplaces is an important objective. In other words, the productivity revolution on sites is also a reform of working styles, and i-Construction is set to significantly reshape the future of the construction industry.

The Role of Surveying and the Effects of Digitalization

In construction projects, surveying plays an important role in accurately grasping existing terrain and structures and providing foundational data for design and construction planning. Traditional surveying work, however, required painstaking point-by-point measurement using total stations and levels, demanding many people and days on large sites.

The introduction of digital technologies has greatly changed how surveying is conducted. For example, by using drones or 3D laser scanners, terrain data that previously took people days to measure can be acquired as surfaces in a short time. Even in forests or large-scale earthworks, aerial photogrammetry from drones can record the entire ground surface as high-density point cloud data with several-centimeter accuracy (inch-level accuracy). Once 3D survey data is obtained, it can be freely remeasured or sectioned on a computer, allowing heights and distances at required locations to be calculated afterward, so surveying work efficiency improves dramatically. Moreover, because the data is digital, it can be shared instantly between the site and the office via the Internet, making remote planning and review easy. In this way, the DX (digital transformation) of surveying makes it possible to understand site conditions more quickly and accurately, producing large benefits across subsequent design and construction processes.

Cutting-Edge Technologies Supporting Surveying DX

Various advanced technologies enable the digitalization of surveying. Major surveying DX technologies increasingly adopted on construction sites in recent years include the following.

• Drone Surveying (UAV Surveying): Small unmanned aerial vehicles (drones) equipped with cameras or LiDAR (light detection and ranging) measure sites from the air. Photogrammetry software generates 3D terrain models (point cloud data) from aerial photographs, and airborne laser surveying directly acquires point clouds with laser scanners, enabling rapid collection of detailed terrain data over wide areas. Because drones can survey steep slopes and forested areas that are hard to access by conventional methods, safety and efficiency are dramatically improved.

• 3D Laser Scanner Surveying: Using fixed terrestrial laser scanners set up on the ground or MMS (mobile mapping systems) mounted on vehicles to measure while driving, this method scans surrounding structures and terrain with high accuracy. Laser-reflected point clouds enable millimeter-level precision (sub-centimeter/inch-level precision) even in complex environments such as building interiors and road corridors. The huge point cloud datasets obtained are processed to remove noise and align multiple scans, then converted into 3D models that are easy to handle in CAD software.

• RTK-capable Smartphone Positioning: This technology combines smartphones with high-precision GNSS receivers to achieve centimeter-level positioning (inch-level positioning) in real time. RTK (Real Time Kinematic) uses correction information from a base station to enhance satellite positioning like GPS, and recently RTK surveying has become easy using a smartphone paired with a small receiver. With a dedicated app, coordinate values of the current position can be displayed instantly on the smartphone screen and coordinates of arbitrary points can be measured easily by one person. Precision surveying that once required million-yen-class GNSS equipment can now be substituted with smartphones, greatly lowering the barriers to surveying.

• AR (Augmented Reality) Technology: AR overlays digital information onto real-world views through a camera, and its use for surveying and construction support is advancing. By displaying design drawings or CAD models on a tablet or smartphone and compositing them with the actual scene, designers and constructors can intuitively compare and verify design data against the site. For example, AR-enabled surveying apps can display virtual stakes or structure models on the ground based on set reference points. This lets teams share a pre-construction visualization on site or guide stake placement on the screen, reducing labor for layout marking (baselines and reference points).

How Surveying Data Supports Integration of Design, Construction, and Inspection

A key to i-Construction is to seamlessly link digital surveying data obtained from the field from design through construction to inspection. Traditionally, measurements taken on site were converted into drawings, which formed the basis for design and construction, and inspection surveying was performed after completion. However, if 3D surveying data is acquired first, that data can be used in various ways in subsequent stages.

• Use in Design: Incorporating current point cloud survey data during the design phase makes planning and quantity estimations more accurate and faster. For example, earthwork volume calculations for land development, which used to be done manually from paper drawings or 2D cross-sections, can now be calculated instantly by overlaying 3D point clouds with the design model to compute cut-and-fill volumes. Likewise, when remodeling existing structures, creating a 3D model from point cloud data can eliminate the need to produce as-built drawings. These applications improve the accuracy of design and estimating and shorten the time required for review.

• Use in Construction: During construction, survey data is applied to quality control (as-built management) and progress management. Quality control checks whether completed structures match the design: by instantly overlaying point clouds from drones or lasers with the 3D design model and comparing them, even slight dimensional deviations can be detected and corrected on site. This reduces the rework that used to be discovered only at inspection. Regular point cloud surveys during construction can digitally record daily excavation and embankment progress. Comparing point clouds over time makes it easy to see at a glance whether work is proceeding according to plan, and allows remote monitoring of site conditions. In other words, surveying data is beginning to function as a platform for near-real-time construction management.

• Use in Inspection and Maintenance: 3D survey data is also powerful for inspections at project completion. Comparing the point cloud of the completed terrain with design data streamlines quantity inspections while leaving objective records. Point clouds enable non-contact measurement of hazardous locations that humans cannot access directly, contributing to safety. Scanning completed structures periodically after completion builds up digital records of changes over time, which can be used to detect displacements and plan repairs during maintenance. Using data consistently from the surveying stage is therefore a key to raising the quality and efficiency of design, construction, and inspection.

Changes Happening on Sites: Labor Reduction, Speed, and Improved Safety

With promotion of i-Construction and surveying DX, actual construction sites are steadily seeing efficiency gains and innovation. Concrete changes occurring at the site level include:

• Labor and manpower reduction: The introduction of digital technologies has made it possible for tasks that previously required multiple people to be handled by a small crew. For example, surveying a large development site can be done with a single drone and one operator; in one case, a survey that used to take two to three people two days was completed in half a day. With limited staff able to handle multiple tasks in parallel, this has a large effect as a countermeasure to chronic labor shortages.

• Speeding up work: The time required for each phase from surveying through design and inspection has been reduced. By using point cloud data, everything from grasping site topography to quantity calculations and quality confirmation can be processed in a way close to real time, reducing waiting times and rework. For example, using point clouds obtained by drone surveying, onsite soil volume can be calculated immediately and decisions such as arranging trucks to haul material can be made on the spot. Faster workflows translate directly into shorter construction periods and ultimately boost productivity across projects.

• Improved safety: Replacing dangerous site work with technology has reduced the risk of occupational accidents. Drones take over surveying at high elevations and steep slopes, and point cloud measurements enable non-contact checks for heavy material handling and deep excavation progress, reducing instances where personnel need to enter hazardous areas wearing helmets. Shorter work durations also reduce physical strain and lower the risk of heatstroke. A safer and more efficient work environment improves morale on site and consequently helps prevent mistakes and improve quality.

• Skill transfer and reforming work styles: Digital tools increasingly provide user interfaces that are easy to use for both young and veteran workers, creating an environment that can be operated regardless of experience or age. Even technicians unfamiliar with ICT can often learn intuitive operations in a short training period. Reducing heavy labor and introducing IT also help correct long working hours, promote taking vacations, and improve work–life balance. Additionally, as the image of construction as “dirty and dangerous” fades and sites become smart workplaces using the latest technologies, the industry is expected to attract and retain younger and more diverse talent.

Smartphone Surveying “LRTK” and the Democratization of Surveying

A groundbreaking tool further accelerating on-site DX is the high-precision smartphone surveying device “LRTK”. LRTK (LRTK) is an ultra-compact RTK-GNSS receiver that attaches to smartphones like the iPhone; although pocket-sized, it enables centimeter-level positioning (inch-level positioning), a revolutionary capability. Attach it to a smartphone and launch the dedicated app, and high-precision latitude, longitude, and elevation can be measured without complicated operations. Acquired coordinates are automatically converted to Japan’s plane rectangular coordinate system and elevation (geoid height) and can be shared instantly to the cloud along with point names and notes. In short, with one LRTK device, a time is approaching when anyone can easily perform surveying anywhere, anytime.

The benefits of introducing LRTK go beyond simplifying and speeding up surveying work. Without expensive dedicated equipment or highly skilled surveyors, site construction managers and craftsmen themselves can measure required points or perform layout marking on the spot, shortening waiting times and reducing communication losses. For example, by overlaying structural layouts from drawings onto the real scene using a smartphone’s AR function while guiding positions with LRTK, pile-driving or equipment installation positions can be placed intuitively. In this way, LRTK is promoting the democratization of surveying, enabling not only specialists but anyone to handle high-accuracy survey data.

LRTK is also offered at a very affordable price point, making one-device-per-person deployment realistic. Previously it was difficult to provide surveying equipment to everyone, but with a compact smartphone surveying device, workers can carry it at all times and measure immediately when needed, dramatically boosting site productivity and autonomy. In practice, small and medium contractors that trialed LRTK reported feedback such as “We scanned the entire site in a short time and even computed soil volumes” and “It’s easy to use yet accurate; it will become our company’s strength,” demonstrating DX effects even on small sites.

The future of construction opened by surveying DX has only just begun. Within the flow of i-Construction, adopting easy-to-use, high-precision tools like LRTK is a shortcut to site reform. Details and case studies of LRTK are also introduced on the [LRTK official site](https://www.lefixea.com). Why not harness the latest technologies and evolve your sites to the next stage?