Seen at CONEXPO-CON/AGG! Cloud-Based Construction Management × As-Built Verification Is Transforming On-Site DX

At one of the construction industry's largest trade shows, CONEXPO-CON/AGG (ConExpo-Con/Agg, [official site](https://www.conexpoconagg.com)), the latest construction technologies and solutions from around the world came together. I visited the event in person, and what especially caught my attention was the digital technologies for cloud-based construction management and as-built verification. By combining these, dramatic transformations are taking place in productivity, quality, and safety on construction sites. In this article, while covering industry trends observed at CONEXPO-CON/AGG, I will introduce innovative technologies and case studies of cloud-based construction management and as-built verification. I will also explain the effects of on-site DX (digital transformation) and the latest simplified surveying solution, LRTK.

Table of Contents

• What is CONEXPO-CON/AGG?

• Benefits of cloud-based construction management

• Importance and challenges of as-built verification (as-built management)

• Latest construction DX technologies seen at CONEXPO 2023 - Cloud BIM and data sharing - On-site use of AR (augmented reality) - Point cloud measurement and 3D as-built management - System integration via API linkage - Digital inspection and automated reporting - IoT sensors and remote monitoring

• Effects and future prospects of on-site DX

• Introduction to LRTK that transforms simple surveying and as-built management

• FAQ

What is CONEXPO-CON/AGG

CONEXPO-CON/AGG (Conexpo-Conagg) is the largest construction industry trade show in North America. It is held every three years in Las Vegas, USA, bringing together the latest construction machinery and technologies from around the world. At the most recent CONEXPO 2023, approximately 2,800 companies exhibited and visitor attendance reached about 139,000. The venue, lined with massive bulldozers and cranes, is impressive, but what was even more striking were the many solutions using digital technologies. Autonomous construction equipment, AI-powered data analytics, cloud-based site management, and the use of VR/AR were among the latest technologies showcased at booths to improve productivity and safety. It can be said to be an event where you can feel firsthand that the digital transformation (DX) of construction sites is becoming full-scale worldwide.

Benefits of Cloud Construction Management

To smoothly advance a construction project, information sharing and coordination among many stakeholders, such as the site, head office, and subcontractors, are indispensable. Cloud construction management is a method of centrally managing on the cloud information related to construction—such as drawings, schedules, photos, and reports—so that anyone can access it in real time. By introducing cloud construction management, you can gain the following benefits.

• Real-time sharing of the latest information: Even if drawings are revised or processes change, once updated in the cloud everyone on site and in the office can immediately view the latest data. This eliminates the need to replace paper drawings each time or to distribute the newest version by email.

• Improved communication efficiency: Because you can add comments to drawings and photos on the cloud and share progress status, instructions and consultations can be issued in a timely manner even from remote locations. This reduces communication delays and improves responsiveness to issues.

• Centralized data management: Schedules, construction checklists, as-built measurement results, inspection records, and all other information can be consolidated in the cloud. Data that was managed separately by each person becomes organized on a single platform, enabling rapid retrieval of the information you need.

• Remote situation awareness: Managers and supervisors can grasp current site conditions without being physically present by using cloud data and live camera footage. This enables more efficient management of multiple sites, reduces travel time, and contributes to productivity improvements.

• Elimination of person-dependent operations: By stopping data management confined to an individual’s desk or local PC and instead accumulating and sharing data in the cloud, handovers remain smooth when personnel change. Information remains an organizational asset, reducing the risk of person-dependent knowledge.

In this way, cloud-based construction management serves as a foundation that digitally connects the site and the office, and even clients and partner companies. In Japan as well, cloud-based construction management apps have begun to spread in recent years, and with the backing of the Ministry of Land, Infrastructure, Transport and Tourism's promotion of *i-Construction* (i-Construction), adoption is progressing across the entire construction industry.

Importance and Challenges of As-Built Verification (As-Built Management)

On the other hand, one aspect that cannot be overlooked when discussing on-site DX is as-built verification. Also called as-built management, this process is a quality control procedure that confirms and records whether the shape and dimensions of constructed structures or developed land match the design drawings. For example, it involves measuring and proving that the height of embankments and the thickness of concrete meet the specified values, and it is an indispensable step for obtaining the client's inspection approval and handing over the completed works.

As-built verification is essential for ensuring quality, but traditional methods had many challenges. Traditionally, craftsmen manually measured dimensions at various locations using marking out, tape measures, and leveling staffs, wrote the measured values on paper drawings and tables, and checked the deviations against the design values. This method tends to give rise to the following problems:

• Surveying work requires manpower and time: On large sites or with large structures, multiple surveying teams must measure point by point, which consumes a great deal of time and effort. Manual measurement limits the number of points that can be measured in a day, creating pressure on the construction schedule.

• Can only measure points, risk of oversight: Manual measurement only captures dimensional data at discrete, separated points, making it difficult to understand the structure as a surface or in three dimensions. Discrepancies between the design and actual conditions in unmeasured areas may go unnoticed, posing a risk of overlooking defects described as "partly different from the drawings."

• Cumbersomeness of photographic records: For as-built verification, it is necessary to photograph rebar, buried items, and the like during construction before they become concealed. Traditionally, these photos were organized in ledgers or files, but this method is prone to missed shots, loss, and organizational errors. If busy site personnel forget to photograph required locations, no evidence remains, and in the worst cases this can lead to rework.

• Complexity of comparing measurements with design values: Tasks such as comparing measured values against tolerances to determine pass/fail and compiling inspection reports for submission have often been done by transcribing into Excel or adding annotations to CAD drawings. When there are many measurement points, organizing this data by hand or on paper becomes an immense task and a burden for field technicians.

In practice, it was the case that traditional as-built management was inefficient and highly prone to human error. However, these challenges are being addressed by new methods that leverage recently emerged digital measurement technologies and the cloud.

Latest DX Technologies for the Construction Industry Seen at CONEXPO 2023

At the CONEXPO-CON/AGG 2023 venue, various technologies related to on-site DX, including as-built verification, were on display. Here, we introduce the main technology trends related to cloud construction management × as-built verification.

Cloud BIM and Data Sharing

In the digital transformation (DX) of construction sites, a key is the use of BIM (BIM: Building Information Modeling) data. BIM is a digital drawing that integrates component information and as-built data into a three-dimensional model, and in recent years there has been a growing trend to share this on the cloud. For example, at CONEXPO, a cloud BIM platform was showcased at the booths of global companies. The site, headquarters, designers, and owners/clients can share a single BIM model on the cloud and access the latest model anytime, anywhere.

This cloud BIM enables the creation of a virtual on-site space called "digital twin". Not only design-stage 3D models, but also point cloud data and 360° photos acquired during construction are overlaid on the BIM model and aggregated in the cloud, allowing real-time reproduction of the actual site in the virtual space. In Japan, Shimizu Corporation has a case in which it shared BIM models, on-site point clouds, and 360° images on the cloud to realize "construction management without going to the site". Using cloud BIM, the office can grasp site conditions in detail, and multiple specialists can remotely view the same model to examine it and issue instructions. As a result, significant productivity improvements have been reported through reduced travel time and reduced communication loss.

On-site Use of AR (Augmented Reality)

AR (Augmented Reality) technology is also a notable technology supporting on-site DX. At the venue, many companies were exhibiting AR-capable smart glasses and tablets. By using AR, digital information can be overlaid on the live images seen on site. For example, if you overlay a design's 3D model at actual size onto the site footage viewed through a tablet's camera, you can share an on-the-spot visualization of the finished product. Because AR can display the completed image — which previously had to be imagined from paper drawings or 2D plans — at full scale in the real space, instructing craftsmen and building consensus becomes more intuitive.

Furthermore, AR also proves powerful for as-built verification. For example, you can 3D-scan a constructed structure, automatically calculate the differences between the resulting point cloud data and the design data, and create a heat map that shows deviations in color. If you overlay this heat map onto site footage using AR, you can visually identify at a glance nonconforming areas such as "which parts are built higher than the design" and "where it has been over-excavated and is lower than the reference" (*shows excesses and deficits with red and blue color distributions*). Defects that previously could only be identified by layout marking or level measurements can be found immediately on the AR screen and corrected on the spot, allowing you to minimize rework.

The range of AR applications is wide; other uses include visualizing hidden structures such as buried pipes and rebar by rendering them as if seen through, and wearing smart glasses on site to receive remote support from experts at headquarters. At CONEXPO, AR solutions that connect remote technicians with on-site teams were demonstrated, and initiatives to facilitate knowledge sharing and skill transfer were showcased.

Point Cloud Measurement and 3D As-built Management

Point cloud data measurement is a technology that dramatically increases the accuracy and efficiency of as-built verification. Point cloud data are three-dimensional coordinate datasets composed of numerous measured points acquired by laser scanners or photogrammetry.

The latest laser scanner equipment was also exhibited at the venue; for example, compact scanners capable of a full 360° scan in about 20 seconds and LiDAR systems mounted on drones that can automatically survey wide areas drew attention.

By using point cloud measurement, you can capture what used to be measurable only as points as surfaces and three-dimensional solids. For example, if you laser-scan the as-built conditions of a dam or road, a dense point cloud of millions of points can accurately capture surface irregularities and slopes. Comparing this to the design 3D model allows even minor deviations to be detected without omission. Also, automatic pass/fail judgment of the as-built condition can be performed in the cloud. At the CONEXPO demo, it was shown that when images captured by a drone are uploaded to the cloud on-site, point clouds and orthophotos (true nadir images) are generated within minutes, and the server automatically completes difference checks against the design data and earthwork volume calculations. Because the as-built results are available immediately after on-site measurement, the time lag of waiting until the next day for results is eliminated, allowing immediate corrective actions or decisions on the next steps.

The fact that this measuring→analyzing→assessing→sharing cycle is dramatically accelerated by leveraging the cloud and point clouds is a major advantage of 3D as-built management. Because all personnel can share and check the same 3D point cloud data and cross-sections on the cloud, discrepancies in understanding between the site and the office do not occur. If the as-built condition can be understood across the surface using point cloud data, even minor surface irregularities (bumps and dips) will not be overlooked and can be corrected early, contributing to quality assurance.

System integration through API connectivity

An important factor in further advancing DX is data integration between various systems (API integration). On-site, a variety of IT tools are used, such as construction management systems, design BIM software, estimating software, document management, and accounting systems, but if these are isolated individually they cannot fully realize the value of data utilization. Therefore, using APIs (Application Programming Interface) to connect systems and automatically link data is becoming increasingly widespread.

At CONEXPO, solutions promoting "open API support" and "integration with third-party systems" stood out. For example, it became possible to automatically import point cloud data and pass/fail inspection information obtained through as-built management into a cloud-based construction management dashboard and display it in real time. There were also examples of linking construction schedule progress and machine operation data to BI tools for analysis to support management decision-making.

API integration enables all on-site data to connect seamlessly, creating an environment where you can operate as "One Team". It eliminates duplicate data entry, reduces data entry errors, and enables each process to be optimized in a data-driven way. In Japan, initiatives to link internal systems with on-site IT tools have already begun, primarily among major general contractors. If a standardized data integration platform becomes widespread for small and medium-sized construction companies, DX across the entire industry will accelerate.

Digital Inspections and Form Automation

On-site DX is bringing transformation to daily construction inspection operations. Until now, many inspections—such as safety patrol checklists and rebar inspection records—have been carried out on paper forms with handwritten entries and seals. Companies are offering digitized inspection apps for these, and at CONEXPO construction management apps supporting electronic forms and digital signatures were on display.

If you check and enter inspection items on a tablet and paste photos taken on-site as they are, a prescribed-format inspection report is generated automatically. There is no longer any need for inefficient tasks like returning to the office to print and attach photos and transcribe them into Excel. Inspection results are saved and shared in real time on the cloud, enabling online witnessing for clients and remote audits. In addition, the digitized inspection history is easy to search and analyze later, which also helps to run the PDCA cycle for quality management.

In addition to the automatic creation of forms, digital tools are also effective for electronic delivery. Various software packages include functions that compile the complete set of final documents into electronic data and automatically aggregate inspection result sheets by item. These features are helping to eliminate situations in which inspectors and site supervisors are forced to sort documents late into the night. DX is making it possible to change the conventional wisdom that "report creation = overtime".

IoT sensors and remote monitoring

At construction sites, the use of IoT (Internet of Things) technology is also expanding. By measuring the movements of heavy machinery, vehicles, and workers with various sensors and sending the data to the cloud in real time, this initiative aims to visualize the site remotely. At CONEXPO, construction equipment manufacturers were promoting services that equip their hydraulic excavators and dump trucks with sensors to monitor operating status, fuel consumption, and location information in the cloud. This allows analyzing fleet (group of vehicles) utilization efficiency to reduce unnecessary idle time and detecting signs of equipment failure to inform maintenance.

IoT is also effective in the field of safety management. Mechanisms have emerged that use smart helmets and wearable sensors worn by workers to detect falls and heatstroke risks and issue alerts. There are also systems that monitor noise, vibration, and dust concentration with environmental sensors installed on-site and notify relevant personnel when values exceed thresholds. All of these are integrated with the cloud, enabling safety officers in remote offices to centrally monitor the status of multiple sites from a dashboard.

In this way, IoT sensors collect real-time data from the field, and by analyzing and displaying it in the cloud, managers can grasp the situation and make decisions without having to visit the site. If an abnormality occurs, it can be detected and addressed instantly, contributing to improved safety and risk reduction. Going forward, combining this with high-speed communications such as 5G will enable even higher-frequency, higher-precision remote monitoring.

Effects and Future Prospects of On-site DX

As we have seen above, DX at construction sites is accelerating thanks to cloud-based construction management and the digitization of as-built verification. Finally, we will summarize the main effects these technologies bring and discuss future prospects.

1. Dramatic improvement in productivity: Faster information sharing and as-built measurement reduce waiting times and rework. By enabling simultaneous remote management of multiple sites, construction can proceed efficiently even with limited personnel. In one case, leveraging the cloud reduced the time required for site inspections to one-eighth of the previous time, and it was reported that labor productivity improved eightfold.

2. Reliable improvement of quality: Point clouds and AR let you grasp the as-built condition down to every corner and do not miss errors on the millimeter level (mm (0.04 in)). Nonconforming areas can be detected and corrected on the spot, preventing defects from being carried over or major rework. Inspections based on digital data also leave comprehensive records and ensure reliable proof of quality.

3. Measures to Reduce Labor and Address Skills Shortages: Digital tools promote the automation and simplification of tasks, helping sites facing labor shortages. There is a growing number of tools that on-site personnel can operate without relying on specialist technicians, such as single-operator drone surveying and devices that enable anyone to achieve surveyor-level accuracy using a smartphone and sensors. This makes it easier to tackle challenges like the decline of veteran staff and the shortage of young technicians.

4. Remote management and work-style reform: The cloud makes location-independent operations possible, allowing management without being permanently stationed on site. By reducing travel time between the field and the office, it shortens supervisors' time commitments and contributes to work-style reform. Also, the use of remote technologies advanced during the COVID-19 pandemic is becoming established even after the pandemic subsides as telework-style on-site management.

5. Improved safety: Automating work in hazardous areas and enabling sensors to assess conditions without people having to approach reduces the risk of workplace accidents. Mistakes and oversights can also be prevented before they occur through digital detection, ultimately contributing to safer, more secure on-site operations.

As for future prospects, these DX technologies will likely become more advanced and widespread. Cloud platforms are expected to become easier to use and cheaper, and to be commonly employed even at small- and medium-sized construction sites. With the advancement of AI technologies, analysis of on-site data and decision-support will also become increasingly automated. For example, a future in which AI automatically provides improvement proposals based on the results of as-built measurements or optimizes construction schedule planning is becoming increasingly realistic.

What’s important is to try introducing DX on-site, even if only on a small scale. Digitizing paper forms, conducting trial surveys with drones— the benefits gained from such initial steps are by no means small. On-site DX does not need to replace everything at once; the key to success is to proceed incrementally, starting where you can.

Introduction to LRTK That Changes Simple Surveying and As-built Management

Finally, as a noteworthy solution that makes it easy to start on-site DX, we introduce LRTK. LRTK (Eru Aru Tī Kē) is a simple surveying system that uses a compact, high-precision GNSS receiver attached to a smartphone. In a demo I saw at the CONEXPO venue, smartphone surveying devices like this LRTK were also drawing a great deal of attention.

By using LRTK, without the need for specialized surveying equipment or a large surveying team, a single field operator can perform centimeter-level positioning and as-built measurement. Specifically, by attaching an LRTK receiver to an iPhone or similar device and simply walking the site, you can obtain high-precision position coordinates in real time. Combined with photos taken by the smartphone’s built-in LiDAR scanner or camera, you can record 3D point cloud data and measurement photos to the cloud.

Features of the LRTK solution:

• High-precision positioning: Using the RTK method, high-precision position information with errors on the order of a few centimeters (a few inches) can be obtained even with smartphone-based positioning. This makes the previously difficult practice of surveying using just a smartphone a reality.

• One-button cloud sharing: Survey and photo data acquired with the dedicated app can be uploaded to the cloud on the spot with a single button. Data analysis begins automatically as soon as measurements are taken on site, and server-side processing completes everything from point cloud generation to comparison against design data.

• Immediate feedback via AR: As-built results such as heat maps created in the cloud can be displayed on the smartphone immediately. By overlaying that onto the smartphone camera view using AR, you can visually identify areas needing repair on the spot. Immediately after measurement on site you can make judgments like "We need to add 5 cm (2.0 in) more fill here," enabling rapid corrective action.

• Simplified photo management: Photos taken with the smartphone automatically record GPS position and orientation, and are pinned to a map in the cloud. There is no worry later about "Where was this photo taken?", and checking for missed shots is easy. The effort to create photo logs is also greatly reduced.

• Support for Ministry of Land, Infrastructure, Transport and Tourism guidelines: As-built data and electronic photo ledgers obtained with LRTK can be output in formats that comply with the Ministry of Land, Infrastructure, Transport and Tourism's site acceptance management guidelines and electronic delivery standards. They can be used directly for inspection submissions, enabling DX while remaining compliant with existing standards.

Thus, LRTK is a tool that embodies the essence of cloud-based construction management × as-built verification in a single device. Even without large-scale equipment or advanced expertise, it enables an easy first step into on-site DX, making it highly valuable for small and medium-sized construction companies and site supervisors. In fact, LRTK has begun to be utilized in domestic municipal projects and private sites, and examples of cases that have dramatically streamlined surveying through inspection are increasing.

If any of you reading this article are thinking, "I want to make as-built management easier and more accurate" or "I'm interested in on-site DX but don't know where to start," why not first consider introducing such simple surveying and cloud-linked tools? For more details on LRTK, information is published on Lefixea's [official website](https://www.lrtk.lefixea.com) and elsewhere, so please check it out.

FAQ

Q1. What kind of event is CONEXPO-CON/AGG? A. CONEXPO-CON/AGG is one of North America's largest construction industry trade shows. It is held every three years in Las Vegas, USA, and features a wide range of exhibits, from construction equipment to the latest technologies. Construction industry professionals from around the world gather there, and it serves as an active venue for new product announcements and exchanges of information on industry trends.

Q2. What are the benefits of introducing cloud-based construction management? A. By introducing cloud-based construction management, project information can be shared in real time, dramatically improving communication efficiency. Because everyone can always view the latest versions of drawings and schedules, transmission errors are reduced and coordination between the site and headquarters is smoother. In addition, being able to monitor the progress of multiple sites remotely leads to reduced travel time and lower management costs.

Q3. What are the advantages of using digital technologies for as-built verification? A. Using digital technologies such as point cloud scanning and AR for as-built verification greatly streamlines measurement work and improves accuracy. Because they can measure large areas as surfaces at once, oversights are reduced, and differences can be intuitively understood through color-coded displays. Compared with manual methods, human error is reduced, and because recording measurement results and generating reports can be automated, there are benefits both in reducing the burden on field technicians and in ensuring quality.

Q4. Are there any challenges or precautions when advancing on-site DX? A. There are several challenges when introducing on-site DX, such as initial costs and the IT literacy of site staff. New equipment and software require upfront investment, but in many cases these costs can be fully recovered in the long term through efficiency-driven cost reductions. Training and education for site staff are also important. However, recent tools have become more intuitive and user-friendly, and people can become accustomed to them by "trying them out first." A useful approach is to run pilot implementations at small sites or on part of the process, and gradually expand the scope while verifying the effects.

Q5. What is LRTK? What will it enable on-site? A. LRTK is a simplified surveying system consisting of a smartphone-mounted high-precision positioning device and cloud services. With this, you can achieve positioning with cm level accuracy (half-inch accuracy) using a smartphone without specialized surveying instruments, and perform 3D as-built measurements and photo documentation by a single person. Measured data is automatically saved to and processed in the cloud, and can be immediately viewed as difference heat maps or point cloud models. In short, adopting LRTK dramatically streamlines on-site surveying and as-built management, and enables immediate feedback of results to support quality control.

Q6. Can small and medium-sized construction companies adopt DX? A. Yes, it is certainly possible. In fact, on-site DX tends to be more effective when started small and in stages. For example, you can begin with inexpensive cloud services for photo sharing and electronic bulletin boards, try outsourcing simple drone surveying, or rent smartphone-connected devices such as LRTK to test. The Ministry of Land, Infrastructure, Transport and Tourism also supports ICT use by small and medium-sized enterprises through i-Construction, and recently services that reduce upfront investment through rental or subscription have appeared. If you trial solutions that match your company’s challenges and fully implement those that show results, even small- and medium-sized companies can reap the benefits of DX.