CIMの最新トレンド2025：LRTKが解説する導入・運用の最前線

In the construction and infrastructure sectors, “CIM (Construction Information Modeling/Management)” has recently become a very important keyword. The Ministry of Land, Infrastructure, Transport and Tourism is also strongly promoting the introduction of CIM as a pillar of productivity improvement and digital transformation (DX) at construction sites, and from fiscal 2023 the Ministry began the principle application of CIM (BIM/CIM) to directly managed construction works. Except for special circumstances, the use of 3D models is required for virtually all design and construction tasks, and CIM is scheduled to become fully mandatory for public works in 2027. CIM utilization is already advancing in projects worth about ¥2.5 trillion annually, and the construction industry is now undergoing a major transition.

In this situation, a new solution attracting attention is “LRTK.” LRTK is a high-precision positioning technology that links CIM and the field, and it is a groundbreaking tool that aligns with the government-led infrastructure DX. This article explains the basics of CIM, the latest trends, and the forefront of introduction and operation as of 2025. Aiming to be useful both to beginners and those already engaged, the latter part of the article also details the principles and features of the new CIM-compatible solution LRTK and its introduction effects. Finally, we touch on a hands-on simple surveying experience using LRTK, providing readers with a perspective that will make them feel “I want to try this myself” or “I want to consider adopting this.”

CIMとは何か？基礎と目的

CIM stands for “Construction Information Modeling/Management” and is a method of digitizing and utilizing information related to construction projects. It is a concept extending BIM (Building Information Modeling), developed in the building sector, to civil infrastructure, centrally managing and sharing data across all project stages such as investigation/surveying, design, construction, and maintenance. In Japan, architecture and civil engineering are often promoted together as “BIM/CIM,” and information management is conducted around 3D models ranging from buildings to social infrastructure.

Main elements included in a CIM model:

• 3D models: Data that represents the shape, dimensions, and spatial relationships of structures in 3D space. Buildings and civil structures can be visualized volumetrically in a virtual space and used for design review, clash checking, and simulations.

• Attribute information: Various information linked to components within the 3D model. Detailed data such as material, strength, dimensions, construction cost, and construction dates are included, and using these enables more efficient cost estimation, schedule management, and maintenance planning.

• Reference materials: External materials associated with the model, such as drawings, photos, point cloud survey data, and reports. Traditional 2D drawings and site photographs can also be linked to the CIM model for combined use as needed.

By introducing CIM, the diverse data described above can be handled centrally, enabling efficient information sharing between clients (project owners) and contractors. Site information that was hard to grasp from paper drawings becomes intuitively “visible” through 3D models, deepening common understanding among stakeholders. As a result, design errors and rework are reduced, and construction quality and safety improve. In other words, CIM can be seen as the foundation of the digital twin (a technology that reproduces the real world in cyberspace) in the construction field. In practice, after the fire at Shuri Castle, CIM technology was used to create a “Shuri Castle digital twin” for use among project stakeholders and the public in the restoration work.

CIM導入の背景と国による推進

In Japan’s construction industry, issues such as a declining working-age population, aging of skilled workers, and labor shortages have long been pointed out. Combined with the “3K” (dangerous, dirty, and hard) working environment at sites, it has been difficult to retain young workers, and the shortage of personnel is serious. To overcome these challenges, the Ministry of Land, Infrastructure, Transport and Tourism launched a productivity improvement initiative called “i-Construction” in 2016. With the goal of improving construction site productivity by 20% by fiscal 2025 through the use of ICT, improvements in construction methods, and smoothing construction schedules, various initiatives such as 3D surveying, automatic control of construction machinery, and use of precast methods have been promoted.

Since 2020, “DX (digital transformation) in the infrastructure field” has also become full-scale, accelerating the utilization of 3D data, optimization of the entire construction production process, and the introduction of new technologies. CIM (BIM/CIM) has been positioned as a core technology in this shift. After a trial phase, the Ministry began principle application of CIM to all directly managed civil engineering works and tasks from April 2023. It was established that “CIM should be used in principle unless there are special circumstances,” and tasks that had conventionally relied on 2D drawings, including planning/design and civil engineering works as well as related surveying and investigation, are being transitioned to 3D model–based workflows. Complete mandatory implementation of CIM for public works is planned for 2027, and CIM is shifting toward becoming a routine working method.

In April 2024, the next step “i-Construction 2.0” was announced. Aiming for highly productive construction sites where a small workforce can work safely and comfortably, the initiative promotes the introduction of smart construction technologies such as remote construction, autonomous operation of construction machinery, and use of AI and robots. From 2025 onward, discussions in public–private forums continue on expanding ICT construction, introducing new technologies, optimizing all processes, and establishing data standards, accelerating nationwide digital reform. BIM/CIM utilization is at the heart of these efforts, and it is said that without adopting BIM/CIM, future public works cannot be handled.

Companies that adopted CIM early have reported significant results. One survey showed an 85% reduction in design errors and a 5–12% reduction in construction costs, with initial investment recouped in 3–5 years. Government and industry surveys have begun to quantitatively demonstrate CIM’s introduction effects, indicating that CIM is not merely a trend but a management strategy with high return on investment. CIM adoption has become an unavoidable issue not only for major general contractors but also for medium and small construction firms. The strengthening of overtime regulations in the construction industry under the 2024 work-style reform–related law (the so-called “2024 problem”) further makes promoting DX urgent so that limited personnel can handle work efficiently. Against this background, the adoption of digital technologies centered on CIM is an industry-wide imperative.

CIM導入のメリットと活用事例

Introducing CIM yields many benefits across every phase of a construction project. Here we present expected effects in the design, construction, and maintenance phases and actual examples of use.

• Design phase: 3D models dramatically improve design accuracy and visibility. Even complex structures can be examined three-dimensionally, and automating clash checks can greatly reduce human error. Using attribute information in models allows cost estimation and schedule simulation, increasing the accuracy of budget and schedule management. Design data can be passed directly to construction and maintenance, preserving information consistency and contributing to improved quality and safety. For example, in a bridge design case, CIM introduction reportedly reduced design errors by approximately 85% and made structural safety verification more efficient.

• Construction phase: Using CIM models on site enhances and streamlines construction management. When everyone involved in construction shares the same 3D model, discrepancies in design intent and communication errors are reduced, leading to improved as-built quality. Recording progress and inspection results as attribute data in the model enables real-time understanding of quantity and quality management. After construction, the 3D model itself becomes an electronic deliverable (as-built documentation), smoothing inspections and handovers. In one tunnel project, combining a CIM model with 4D simulation and VR/AR technologies optimized the construction plan and shortened the installation period for precast members by 40% compared to the original plan. By pre-examining construction procedures and crane movements on the model, unnecessary steps in cramped sites were reduced and safety risks lowered—an excellent example.

• Maintenance phase: CIM models are powerful for maintenance after completion. By continuously appending inspection results and repair histories to the as-built 3D model, a digital twin of the structure is created. This allows time-series understanding of aging and deterioration and facilitates future deterioration prediction and repair planning. Maintenance, which used to require flipping through paper ledgers and drawings to find past records, can be streamlined by centralized model-based management. For example, in bridge maintenance, marking damage locations on a 3D model and linking latitude/longitude, photos, and inspection dates makes it possible to precisely locate the same spot at the next inspection. Analyzing accumulated data helps prioritize repairs and budget planning, contributing to reduced life-cycle costs and preventive maintenance of infrastructure assets.

As described above, CIM brings significant benefits in three areas: improved design quality, increased construction productivity, and streamlined maintenance. The Ministry expects CIM dissemination to enable future work-style reform at construction sites, improved cost structures, and enhanced safety. Although significant effort is required to introduce CIM, the value is commensurate with the effort, and CIM utilization will continue to expand across more sites.

CIM導入のステップ（導入までの流れ）

When first implementing CIM, success depends on proceeding in stages rather than applying it to all operations at once. The following are common steps for CIM introduction.

• Organizational setup and goal setting: First, secure understanding and commitment from management and form a project team. Clarify the purposes of CIM introduction (e.g., efficiency, improved accuracy), and develop an internal promotion structure and roadmap.

• Tool selection and environment setup: Next, select the software and hardware needed for CIM. Consider 3D CAD/BIM software for design, point cloud processing tools, cloud sharing platforms, and other tools suited to your business. At the same time, prepare the ICT environment, including high-performance PCs and tablets.

• Pilot projects for trial: Conduct trial implementation of CIM on small model projects or part of a workflow to gain practical experience. For example, try creating a 3D model for a specific bridge or land development project within a manageable scope. Collect feedback from the field and verify issues and effects.

• Establish standard workflows: Based on insights from pilots, develop workflows and internal standards that incorporate CIM. Define rules for model creation procedures, attribute input, data sharing methods, and deliverable formats. Prepare guidelines and templates to make operation easy for everyone.

• Company-wide rollout and training: Once standardized, expand CIM adoption to other projects and departments in stages. Improve technical skills through internal training and study sessions and share knowledge. It is important that all employees understand the purpose and benefits of CIM, not just how to use the tools, so that CIM becomes established at the site level.

• Effect verification and continuous improvement: After introduction, verify effects for each project and implement improvements where issues arise. Stay aware of the latest technology trends and guideline updates, and update operations as needed. By running a continuous PDCA cycle, maximize the benefits of CIM adoption.

CIM運用のポイント

After introducing CIM, several points should be noted to ensure continuous utilization at the site.

• Keep models up to date: Update 3D models created during design whenever changes occur in construction, managing them as “living models” that always reflect current conditions. Feedback construction changes and as-built differences into the model to synchronize the model and the site. This enables accurate as-built models at completion that can be used directly for handover and maintenance.

• Smooth information sharing between site and office: Use cloud systems or shared servers to create an environment where stakeholders can view and edit models, point clouds, drawings, and photos in real time. Ideally, site managers should be able to check the latest models on a tablet and designers should be able to check site data from the office, enabling information linkage beyond geographic distance. For example, upload field data acquired by GNSS positioning equipment or drone surveys to the cloud and integrate it into the model. Reduce time lags between site and office to create a state where the latest information is accessible anytime, anywhere.

• Data standardization and quality control: Enforce internal standards for model data and drawings such as naming conventions, layer structures, and coordinate systems so that everyone handles data under the same rules. Backup and version control of data are also important. Clearly record change histories to avoid coexistence of old and new models. A quality-check system to confirm the accuracy of models and attribute information (double checks or placement of specialized personnel) is also necessary.

• Human resource development and organizational strengthening: To establish CIM at sites, human resource development is essential. Appoint personnel knowledgeable in BIM/CIM (BIM manager, CIM coordinator, etc.) to support the field. Encourage regular internal training and participation in external seminars to acquire the latest skills. Create mechanisms to collect questions and improvement suggestions from the field and promote knowledge sharing and horizontal rollout.

• Continuous improvement and responsiveness to the latest information: Introduction is not the end; address issues revealed during operation as they arise. Conduct post-project reviews with stakeholders to identify good practices and issues to apply to future projects. The CIM environment is constantly evolving with Ministry guideline revisions and new software and devices—keep up with the latest information and update operational rules and tools flexibly as needed.

2025年のCIM最新トレンド

Finally, let’s review the latest CIM-related trends noteworthy as of 2025. Advances in technology and industry trends are broadening CIM’s scope of use.

• Policy and standardization progress: The Ministry continues annual efforts to prepare the environment for CIM dissemination. As of 2025, CIM application is expanding not only to directly managed works but also to local government public works, and cases requiring deliverables in the form of 3D models are increasing for projects above certain design amounts. From 2026 onward, the “CIM in principle” policy is expected to spread at the municipal level, and 3D model utilization will become standardized across the industry. The Ministry regularly revises standards such as the “BIM/CIM Utilization Guidelines” and “Deliverables Preparation Manual,” and the latest related standards were published in March of Reiwa 6. Companies are required to track the latest standard trends and update their operational rules accordingly.

• AI and automation technologies: Advances in AI and robotics are making next-generation construction management combined with CIM more realistic. For example, systems are being researched in which sensors and cameras capture site progress in real time and AI automatically checks quality and safety on a digital twin; if abnormalities are detected, AI can alert relevant parties, and autonomous systems to support human supervision are expected in the future. Development of autonomously controlled construction machinery and site robots is also progressing, and construction based on 3D design data—such as automated excavation and paving—is beginning to be realized. These smart construction technologies are also attracting attention as measures to cope with severe skilled labor shortages.

• Practical use of XR technologies (AR/VR): Combining AR (augmented reality) and VR (virtual reality) with CIM is another trend. Tools that overlay CIM models onto real scenes via tablets or AR glasses to intuitively compare design and site conditions are becoming practical. For example, projecting a 3D model of the expected completion on-site to confirm placement and scenery or using VR to simulate the interior of a structure for training construction procedures are expanding uses. These applications are expected to accelerate on-site decision-making and improve skill transfer efficiency.

• Cloud integration and open data: For infrastructure projects involving multiple companies and departments, cloud-based data integration is becoming increasingly important. Use of CDE (Common Data Environment) platforms on the cloud, where design offices, contractors, and clients share a single latest model, is growing. The standardization of open formats for BIM/CIM data exchange (such as IFC) and system interoperability is improving, enabling smooth exchange of 3D models and attribute information between different software. Improved data compatibility will contribute to cross-industry collaboration and future use of digital archives.

• Integration of digital twins and IoT: In maintenance, building digital twins that combine IoT sensors and CIM models is attracting attention. Installing vibration and strain sensors on bridges and tunnels and reflecting real-time monitoring data on CIM models allows continuous monitoring of structural health. When abnormal values are detected, dangerous areas can be visualized on the model and rapid inspection and repair initiated. Real-time digital twin technology holds great potential for preventive maintenance of infrastructure and rapid disaster response.

As of 2025, the CIM environment has made significant progress both technically and institutionally. Continuously catching the latest trends and updating your company’s CIM utilization will become ever more important to maintain competitiveness.

LRTKとは何か：CIM時代の高精度測位ソリューション

Next, we introduce “LRTK,” mentioned in the article title, along with its overview and features. LRTK is a new surveying and positioning solution developed for the BIM/CIM era, created by Reflexia, a startup spun out of the Tokyo Institute of Technology. The core device, the “LRTK Phone,” is a palm-sized high-precision positioning terminal designed to be used in conjunction with a smartphone. Utilizing the latest RTK-GNSS technology, its main feature is that anyone on site can easily measure positions with centimeter-level accuracy (cm level accuracy (half-inch accuracy)).

Main features of the LRTK Phone:

• Surveying equipment that fits in your pocket: The LRTK Phone is lightweight and slim, weighing about 125 g and about 13 mm (0.51 in) thick, and is attached to a smartphone for use. It has a built-in dedicated battery, achieving portability in the field without complicated wiring.

• High-precision positioning via Real-Time Kinematic (RTK): Ordinary GPS has errors on the order of meters, but RTK applies correction information from a base station in real time to reduce horizontal and vertical errors to the order of several centimeters (cm level accuracy (half-inch accuracy)). LRTK miniaturizes this RTK technology into a smartphone-linked device, allowing field users to obtain positioning accuracy comparable to specialized surveying equipment. In measurements, single-shot positioning shows horizontal errors of about 1–2 cm (0.4–0.8 in), and averaging multiple measurements can further improve accuracy.

• One-touch operation and automatic coordinate conversion: Using the LRTK app (smartphone app), simply press a button at the point you want to measure and positioning completes; latitude, longitude, and elevation data are recorded. It supports Japan’s geodetic system JGD2011 (the global geodetic system) and the plane rectangular coordinate system, automatically converting acquired latitude/longitude to plane coordinates and calculating geoid height, so even those without surveying expertise can obtain accurate site coordinates.

• Cloud sharing of positioning data: Coordinates and notes for measured points can be uploaded to the LRTK Cloud (web platform) with one button. Office colleagues can immediately check field point information (point location, name, time, notes, etc.) on a map, enabling real-time data sharing between site and office. This embodies the CIM goal of “linking site and model data,” making it easy to reflect the latest site information in the model from remote locations.

• Durability designed for field use: The device itself is dustproof and waterproof (IP-rated), allowing use on dusty civil engineering sites and in light rain. In environments where satellite signals tend to be unstable—such as under elevated bridges or near tunnel portals—positioning can be maintained with auxiliary technology using built-in IMU (inertial measurement unit). When radio signals are interrupted, the device uses dead-reckoning to retain position, offering flexibility to handle cases that were difficult with conventional surveying, such as tunnel surveys.

• An affordable surveying tool anyone can use: Despite its performance, the LRTK series is priced very affordably. Sites and small contractors that could not purchase expensive surveying equipment can easily adopt it, and its aim to be a “universal surveying tool anyone can obtain” is a major attraction.

Overall, LRTK is an all-purpose surveying device aimed at “accurate positioning anytime, anywhere, by anyone.” Because it greatly streamlines the process of accurately digitizing site conditions—an important aspect of CIM utilization—it will strongly support CIM introduction. Using LRTK, measurement tasks that previously required a specialized surveying team can be performed quickly by site technicians themselves, allowing immediate incorporation of the latest field data into the model. The next section looks at a simple surveying experience using LRTK.

LRTKによる簡易測量を体験してみよう

To really appreciate CIM’s appeal, trying digital surveying on site is the best approach. LRTK dramatically lowers that barrier. Suppose you are at a construction site and want to carry out tasks such as stakeout or as-built verification that previously required a specialized surveying team. In such a case, attach an LRTK Phone to your smartphone and tap the app button at the point you want to measure; within a few seconds you will retrieve the accurate coordinates of that point. The acquired data can be annotated with point names and notes and shared to the cloud instantly, enabling real-time information sharing with colleagues at a remote office.

This “simple surveying” lets you personally experience the full process of instantly digitizing the latest site conditions and reflecting them in a CIM model. The convenience of completing tasks that used to require paper drawings and tape measures with just a smartphone is something you will not want to give up once you experience it. To feel the effects of CIM firsthand, try high-precision field measurement with LRTK—you will likely be surprised by unprecedented efficiency and peace of mind.