On-site Soil Volume Management Is Revolutionizing Construction Workflows! Streamline Progress Management with DX

Table of Contents

• Why on-site soil volume management (volume calculation) is required

• Traditional soil volume calculation methods and their challenges

• What is a smartphone-integrated soil volume calculation tool?

• How anyone can perform fast, high-precision surveying

• Benefits of on-site data sharing via cloud integration

• Effects smartphone surveying tools bring to the field

• Simplified surveying with LRTK

• FAQ

Why on-site soil volume management (volume calculation) is required

On civil engineering and land development sites, it is extremely important to accurately grasp the soil volume—the volume of excavated or filled earth. For as-built management and reporting to clients, teams must always know “how much soil has been moved” and “how much remains to be filled or excavated.” However, until recently it has not been easy to calculate soil volume instantly on-site. The common practice was to hire survey specialists to take careful measurements, bring that data back to the office, and perform analysis and volume calculations there, which took time to produce results. As a result, even when on-site staff wanted to “know the exact soil volume right now,” they often could not get an immediate answer and had to rely on experience and intuition to make decisions.

In recent years, the construction industry has faced major challenges such as labor shortages and work-style reforms, increasing demand for efficient construction management methods. With the Ministry of Land, Infrastructure, Transport and Tourism promoting *i-Construction*, on-site digitization—so-called on-site DX—is accelerating. Against this backdrop, expectations for “tools that can perform volume calculation on-site” have risen sharply. If a tool could provide soil volumes instantly on-site, field staff could verify as-built conditions without survey specialists, dramatically improving construction progress management efficiency. Having accurate quantities at the needed time would help prevent rework and enable rapid decision-making, ultimately contributing to improved productivity across the construction process.

Traditional soil volume calculation methods and their challenges

Until now, the following traditional methods have mainly been used to calculate soil volumes on earthwork sites. Each has its strengths, but all face challenges when it comes to obtaining accurate soil volumes instantly on-site.

• TS (total station) surveying: This method sets up an electronic distance meter (total station) to measure the heights and positions of many points on site, creates a terrain model, and calculates volumes. Although highly accurate, measuring numerous points on large sites takes time and requires specialized surveyors and assistants. Because it takes effort and days from measurement to volume calculation, it is not suited for “producing results on the spot.”

• Average cross-section method for volume calculation: A long-used method in roadworks, it creates cross-sections of the terrain at regular intervals, calculates cut and fill volumes for each segment on drawings, and sums them up. It is simple in principle but cannot fully reflect terrain changes between cross-sections and yields approximate values. Creating cross-sections, drawings, and calculations also takes time, making real-time understanding impractical.

• Photogrammetry using drones: A more recently adopted method where drones (unmanned aerial vehicles) capture aerial images, and photogrammetry software creates 3D models and contours from the photos to calculate volumes. Effective for efficiently covering wide areas, it is nevertheless susceptible to weather and wind and requires flight permission procedures. Processing the resulting image data requires expertise, and it is difficult to complete from capture to result instantly. To know volumes immediately on-site, a certain amount of time and post-processing are unavoidable.

• Visual estimates based on experience: In some cases, operators or site supervisors estimate soil volumes roughly—for example, “about how many dump truck loads.” However, such human-judgment estimates tend to have large errors and can lead to discrepancies with clients or disputes during progress quantity assessments (acceptance of as-built quantities).

As described above, traditional soil volume calculation methods suffer from issues such as requiring time and effort, needing specialized skills, and lacking real-time capability. Even if teams want accurate soil volumes immediately, the time lag from measurement to analysis makes on-the-spot answers difficult. Moreover, conveying quantities as numbers alone is not intuitive; using paper drawings or tables to explain conditions requires time and effort to share status with clients or other departments.

What is a smartphone-integrated soil volume calculation tool?

To address these challenges, smartphone-integrated soil volume calculation tools have emerged. This is a new measurement system that combines a small positioning device attached to a smartphone, a dedicated app, and cloud services. By simply attaching a pocket-sized device to a smartphone, the phone you normally use instantly becomes a high-precision surveying instrument.

The main components of a smartphone-integrated tool are as follows.

• High-precision GNSS receiver: An external GPS receiver attached to the smartphone. It supports RTK (Real Time Kinematic) GNSS and, by applying correction information to satellite positioning, achieves high positioning accuracy within a few centimeters (within a few in). While built-in smartphone GPS typically has errors on the order of several meters (several ft), using this external GNSS receiver enables position measurements with accuracy comparable to surveying instruments.

• Smartphone-built-in sensors (LiDAR and camera): Modern smartphones are equipped with LiDAR scanners (laser-based distance measurement) and high-performance cameras that can scan surrounding terrain and structures to acquire 3D point cloud data. This allows fine terrain undulations to be recorded as digital data, which can later be used for precise volume calculations.

• Dedicated surveying app: A surveying app that runs on the smartphone. It receives high-precision position information from the positioning device while processing point cloud and image data obtained via the phone’s LiDAR and camera in real time. It includes analysis functions such as volume calculation, enabling soil volumes to be computed directly on-site. The user interface is designed to be intuitive so that anyone can perform measurements by following on-screen guidance for moving the smartphone.

• Cloud integration service: A service that stores and shares data acquired by the surveying app via the Internet. Uploading 3D models and numeric data created on-site to the cloud lets office PCs and members at other sites view the information immediately. Point cloud data and volume results can be viewed in a browser without special software, allowing remote reporting and discussion to proceed smoothly.

Using such smartphone-integrated tools brings high-precision surveying—previously requiring large equipment and skilled personnel—closer at hand. There is no need to carry heavy tripods or surveying instruments around the site; a smartphone and a small device can cover wide survey areas. It is, indeed, an innovative solution that makes “easy soil volume calculation by anyone” possible.

How anyone can perform fast, high-precision surveying

The reason measurements using smartphone-integrated tools are both fast and highly accurate lies in their technical mechanisms. Let’s look at the key points that make high precision possible with simple on-site operation.

First, RTK-capable high-precision GNSS is the key to improved accuracy. The small GNSS receiver connected to the smartphone uses correction information from a base station (or augmentation signals from quasi-zenith satellites) to enable constant centimeter-class positioning. Because positioning accuracy is high, the acquired point cloud data and measurement points are tagged with absolute coordinates, allowing on-site measurements to be directly compared with the design coordinate system or datum. Traditionally, aligning laser scan data to survey coordinates required a separate post-processing step, but smartphone-integrated tools can determine accurate position coordinates at the time of measurement.

Next, 3D scanning using the smartphone’s LiDAR sensor and camera speeds up measurement. Simply walking around the soil pile or excavation area with the phone in hand allows the LiDAR to obtain hundreds of thousands of distance points per second and instantly form a point cloud. Combining this with the high-precision position information enables immediate calculation of dimensions and volumes on-site. Normally, processing point cloud data from 3D scans on a PC would take considerable time, but smartphone-integrated tools perform automatic processing within the app, so results are obtained almost concurrently with measurement.

Augmented reality (AR) technology is also leveraged. Because the smartphone screen can overlay virtual measurement results onto the real camera view, understanding results becomes highly intuitive. For example, based on the acquired soil volume data, overlaying a colored heat map or numeric indicators showing “how many centimeters remain to reach the design surface” onto the site video makes surpluses and shortages immediately visible. Even inexperienced workers can grasp conditions visually and make appropriate on-the-spot decisions.

Additionally, a user interface designed for ease of use is an important factor. Users select the surveying mode according to the target, follow screen guidance to move the smartphone, and data acquisition and analysis are performed automatically. Real-time display of positioning status and accuracy gives first-time users confidence that they are measuring correctly. The app minimizes technical jargon and is designed to be completed with simple button operations, making the surveying tool usable even by those less comfortable with machinery.

Benefits of on-site data sharing via cloud integration

Smartphone-integrated tools are not only fast at measurement—their value is amplified by cloud integration. Uploading data acquired on-site to the cloud allows geographically dispersed stakeholders to share information.

For example, if soil volume measurements taken on-site are uploaded to an internal shared site via the cloud immediately afterward, headquarters and teams at other sites can view the information right away. Because 3D point cloud models, photos of measurement locations, and calculated soil volume figures can be checked on the cloud, stakeholders can understand site conditions with a strong sense of presence even without being on-site. This speeds up reporting to the site agent or supervisors and enables prompt additional instructions as needed.

Accumulating data on the cloud also makes it easy to manage daily progress data over time. For instance, scanning excavation areas and recording soil volumes each day at the end of work allows you to view the progression of as-built quantities over time in the cloud. Later, when verifying “how much soil was removed at which time” or “how far along we are compared to the design quantities,” having orderly cloud-stored data makes review tasks smooth.

Of course, uploading to the cloud can be flexibly configured per project. Sensitive data can be kept locally while sharing only the necessary information securely with one click. Eliminating the need to hand over paper documents or USB drives, and making “measure on-site and share immediately” the norm, is a major advantage supporting on-site DX.

Effects smartphone surveying tools bring to the field

Introducing smartphone-integrated surveying tools brings various effects to civil construction management sites. Below are the main effects summarized.

• Optimization of construction planning and progress management: Instant access to soil volume data allows on-the-spot revision of construction plans and adjustment of heavy equipment operations. For example, if excavation volume turns out to be larger than planned, additional dump trucks can be arranged proactively. Constantly knowing accurate progress quantities enables waste-free plan changes and can shorten schedules.

• Prevention of mistakes and rework: Being able to visually confirm deviations between the design and current conditions on-site prevents over-excavation or over-filling. Discrepancies that used to be discovered only at as-built inspections can now be corrected immediately through real-time measurement. This reduces rework, avoids unnecessary costs, and shortens construction time.

• Smoother communication: Sharing digital 3D data and AR displays speeds up information exchange between site and office, and with clients. Visual data facilitates faster consensus than textual or numeric reports. During progress quantity assessments or inspections with stakeholders, objective data helps proceedings go smoothly.

• Contribution to skill transfer and human resource development: Because surveying with a smartphone is easy to operate, young employees and new staff can be entrusted with on-site surveying. Tasks that previously relied on veteran experience and intuition can be supported by the tool, helping to eliminate knowledge concentration and enabling consistent-quality measurements even when experienced personnel are absent—helpful for addressing labor shortages.

• Improved safety: Even dangerous slopes or deep excavations can be measured non-contact from a safe distance. Traditional surveying on unstable ground posed fall risks, but smartphone surveying removes the need for unsafe postures. AR displays can also emphasize hazardous areas, providing benefits for on-site safety management.

In this way, smartphone-integrated tools for on-site soil volume calculation do more than streamline surveying—they produce positive ripple effects across construction management. Real-time access to accurate data speeds up site decision-making and enhances overall productivity and safety, making these tools true trump cards for on-site DX.

Simplified surveying with LRTK

As an example of these innovative smartphone surveying tools, there is simplified surveying using LRTK. LRTK is a system developed by Reflexia Co., Ltd., composed of a smartphone-integrated high-precision GNSS receiver and cloud services, used by attaching it to iPhones or Android smartphones. By using the dedicated LRTK app to perform 3D scanning and positioning on-site, anyone can perform precise soil volume calculations (volume computation) in a short time.

With LRTK, you can complete surveying with a palm-sized device without carrying a heavy total station. For example, to measure the volume of embankments or backfill, simply walk around the target while scanning with an LRTK-equipped smartphone, and the cubic meter (m^3) volume will be calculated on the spot. Measurement results can be checked immediately on the phone screen and synced to the cloud with one touch for internal sharing. The ability for on-site personnel to obtain and use necessary data without waiting for a surveying team is a major strength.

LRTK surveying is also designed to be easy for first-time users. The app’s screens are in Japanese and easy to understand, and operation guides are displayed for each surveying mode, allowing even those unfamiliar with machinery to use it confidently. If users are unsure during on-site operation, uploaded cloud data can be reviewed by off-site supervisors or technicians for advice, ensuring solid support.

If you are currently looking for a “tool that can perform volume calculation on-site,” simplified surveying using LRTK is a strong option. For sites aiming to improve efficiency and reduce labor in earthworks, smartphone-based surveying methods using the latest technology are now indispensable. Please consider introducing it to your company’s sites.

FAQ

Q: What exactly is a smartphone-integrated soil volume calculation tool? A: It is a system where a small high-precision positioning device is attached to a smartphone and a dedicated app is used to measure and calculate soil volumes. It dramatically improves smartphone GPS accuracy and automatically calculates volumes from on-site 3D data obtained by the camera and LiDAR. In short, it turns the smartphone you normally use into a precision surveying instrument.

Q: Can people without surveying expertise use it? A: Yes. Because complex settings and calculations are handled automatically by the tool, it is designed to be usable by anyone. Measurement is completed simply by moving the smartphone according to the app’s on-screen instructions, so even those with little experience can use it confidently. Training time required is minimal and users can start intuitively.

Q: What level of measurement accuracy can be expected? A: With GNSS RTK, under ideal conditions horizontal positioning of about ±2–3 cm (±0.8–1.2 in) and vertical accuracy on the order of a few centimeters can be expected. In actual field conditions, centimeter-level accuracy (half-inch accuracy) enables soil volume assessment comparable to conventional optical surveying instruments.

Q: How does it compare to drone surveying? A: Smartphone-integrated tools are more convenient than drones and can be used immediately by anyone on site—that is a major advantage. They avoid concerns about flight permission and weather and are suitable for routine use on small sites. They also provide real-time results that can be applied immediately to construction. However, drones can be more efficient for very large survey areas, so it is desirable to choose the method according to the use case.

Q: How are measurement data saved and shared? A: Measured data are stored on the smartphone and can be uploaded to the cloud as needed. If saved on the cloud, point cloud data and results can be viewed from office PCs via a browser, and sharing links can be sent to stakeholders. Data can also be exported as 3D models or CSV files, making them useful for internal reports or further analysis in other software.