Eight Ways to Use 3D Scanning for Stone Structures｜From Preservation and Restoration to Exhibition

Table of Contents

• Why 3D scanning is needed for stone structures

• Use 1: Create high-precision baseline records for current-state preservation

• Use 2: Compare and verify progression of deterioration and deformation

• Use 3: Improve accuracy of restoration planning and construction review

• Use 4: Help understand areas of loss and relationships among components

• Use 5: Record including surrounding topography and spatial relationships

• Use 6: Smooth sharing of survey results and consensus building

• Use 7: Deploy for exhibition, public display, and educational outreach

• Use 8: Establish a recovery foundation for disasters and accidents

• Perspectives for successfully implementing 3D scanning of stone structures in practice

• Summary

Why 3D scanning is needed for stone structures

Stone structures may appear robust and slow to change at first glance, but in reality they undergo gradual condition changes due to wind and rain, temperature fluctuations, freeze-thaw cycles, ground movement, vegetation influence, and human contact. Manifestations of change are diverse: surface wear, broken corners, crack widening, plinth settlement, component displacement, and reduced legibility of inscriptions. Moreover, these changes are often not sudden enough to be noticed by eye, and there are many cases where the deterioration was already advanced by the time it was detected.

Traditional recording methods—photography, manual measurements, orthographic drawings, and field notebook entries—have been widely used and will remain important, but they have limits in consistently capturing complex surface irregularities, three-dimensional configurations, and slight displacements of stone structures. Photographs excel at visual information but need supplementary data to verify dimensions. Manual measurements are reliable but tend to focus on points, making full-shape reproduction labor-intensive. Drawings are effective, but when the underlying measurement density is insufficient, details can be lost.

3D scanning addresses these challenges by acquiring the entire object as surfaces, allowing post hoc inspection of any cross-section or dimension. Deformations or tilts overlooked on site can become clear for the first time in the data. Even when revisiting a site is difficult, sufficient digital records enable multiple re-analyses back in the office. This is a major advantage for heritage surveys constrained by time, pre-restoration inspections with many stakeholders, or sites with scaffolding and safety restrictions.

Furthermore, a stone structure’s value is not always complete as an isolated object. Its meaning may include surrounding topography, its relationship to the approach path, continuity with plinths and masonry, and placement relative to other stone objects. Using 3D scanning makes it possible to record not only the solitary shape but also the surrounding environment, facilitating later comparisons and assessments of environmental change. Grasping a stone structure as “an entity within a place” rather than only as an object increases its practical value.

Use 1: Create high-precision baseline records for current-state preservation

The most fundamental and important use of 3D scanning for stone structures is to create high-precision baseline records for current-state preservation. As a prerequisite for preservation and restoration, objectively recording the present condition is indispensable. If shape, dimensions, tilt, surface undulations, losses, and joint conditions can be preserved three-dimensionally, the foundation for subsequent decisions becomes significantly stronger.

Surface ornamentation and marks of workmanship on stone structures can themselves be valuable. For example, carving depth, edge chamfers, degree of weathering, and remaining tool marks are information relevant to dating and understanding fabrication techniques. Photographs alone can be affected by lighting and shooting angle, so they may not fully preserve what is visible. By retaining shape information with 3D scanning, you can inspect surface reliefs from different angles without dependence on lighting conditions.

Baseline records also mean not only “preserve because it may be useful later” but also “preserve because it can only be recorded now.” Once restoration, relocation, or disassembly repairs begin, you cannot return to the pre-construction state. The same applies when disasters, theft, or contact accidents occur. Therefore, current-state recording should be positioned not as an ancillary activity to be done when there is time, but as part of the preservation act itself.

When recording with 3D scanning, acquire not only the object as a whole but also the base, plinth, surrounding pavement, drainage conditions, and proximity to vegetation; this broadens interpretive possibilities in the future. Recording only the single-object shape can be insufficient for analyzing deterioration factors. For instance, if weathering is progressing in a particular direction, relating it to the openness of the surroundings, water flow, or tree positions can help identify causes.

Thus, baseline records created by 3D scanning are the starting point of preservation and a shared asset that benefits every subsequent stage. Accurately recording first is the first step in putting stone structures to practical use.

Use 2: Compare and verify progression of deterioration and deformation

In stone structure conservation, it is important not to stop at a single recording but to enable comparison over time. 3D scanning makes it easy to quantitatively grasp changes in shape and displacement by overlaying data acquired at different times. This is a major advantage unique to 3D data that is difficult to achieve by comparing photographs.

Stone deterioration appears in many ways: surface flaking, corner wear, fine losses, bulging, cracking, and settlement or tilting of components. Even where visual inspection tends to result in subjective impressions such as “it seems worse than last time,” 3D data can clearly show “where” and “to what extent” changes occurred. Quantitative comparison results are especially persuasive when explaining the need for conservation to managers and clients.

Because many stone structures are outdoors, they are subject over the long term to repeated wetting and drying, winter freezing, salt exposure, and small ground movements. These influences may not be noticeable over short periods, but over several years they will manifest as measurable shape changes. Regularly conducting 3D scans under consistent approaches allows prioritization for conservation. By focusing on objects showing large changes, you can increase management efficiency within limited personnel and budget.

Comparing deformations is also useful for evaluating the stability of installation conditions, not just the stone body itself. Early detection of slight plinth settlement, local ground height differences, or progressive tilting can help prevent major damage. Changes that are not obvious externally may be recognized as warning signs in three dimensions, making 3D monitoring effective from a preventive conservation perspective.

Crucially, it is not enough simply to accumulate data; records must be maintained in a comparable manner. Standardizing measurement ranges, reference approaches, and whether to include surroundings will improve verification accuracy in later years. 3D scanning is both a recording method and a mechanism for continuous condition monitoring.

Use 3: Improve accuracy of restoration planning and construction review

In restoration of stone structures, how accurately the current state is understood affects selection of methods and the validity of work sequences. 3D scanning is effective for increasing the information available before restoration and improving foresight during construction. Because it allows three-dimensional understanding of dimensional relationships, tilt, and joint conditions—not just visual impressions—it makes it easier to develop feasible restoration plans.

For example, in stone structures composed of stacked components, it is necessary to determine which parts bear uneven loads and where displacements have occurred. Small tilts can amplify effects toward the upper parts and significantly affect temporary works and disassembly sequencing during restoration. With 3D data, you can objectively confirm positional relationships and axis shifts of each component, facilitating pre-construction review.

When considering restoration policy, “how far to intervene” is always an issue. Excessive repair can compromise original character, while too little intervention can leave safety and durability issues unaddressed. Detailed understanding of the current condition via 3D scanning makes it easier to discuss which changes require urgent action and which losses can be left as is. This is especially useful when designers, contractors, managers, and scholars are all involved.

3D scanning also helps with scaffolding planning and workflow layout. If you understand not only the object but also the surrounding environment three-dimensionally, confirming delivery routes, work spaces, and safety clearances becomes easier. On sites with difficult conditions—temple precincts, slopes, graveyards, or along approach paths—this prior understanding reduces construction risks.

Restoration is not simply “fixing broken things” but an exercise in deciding what to protect, what to leave unchanged, and how far to restore. 3D scanning provides the common facts that support those decisions. The result is improved restoration accuracy and greater ease in fulfilling accountability.

Use 4: Help understand areas of loss and relationships among components

Stone structures often have components that are partially missing, rejoined after past breakage, or subject to later repairs. It is therefore necessary to judge whether the current shape represents the original and to what extent later additions are present. 3D scanning is useful for understanding these component relationships.

In identifying losses, it is important not only to note that something is missing but also to confirm the orientation of fracture surfaces, the remaining geometry, and continuity with surrounding parts. Shape information is a major clue when considering whether breakage was caused by external force, weathering, or past movement during handling. With 3D data, even if long on-site proximity is not possible, fracture surfaces and joint relationships can be examined in detail later.

For stone structures composed of multiple elements, accurately recording the relative positions of each element provides reference criteria for disassembly repairs and reassembly. Even when on-site marking is insufficient, three-dimensional records allow you to recheck orientation, seating, and gap distribution. This is important for performing restoration that respects original positional relationships.

Some stone structures bear inscriptions or patterns on their surfaces that become difficult to read due to loss. 3D scan data can visualize slight surface elevations and depressions under different conditions, helping to detect traces that are hard to see with the naked eye. While not all inscriptions will become fully legible, 3D data often provides more material for analysis than photographs alone.

When considering filling losses, 3D data is also effective. It makes it easier to test how to define the contour to be supplemented, whether repair materials will be excessive, and whether the repair will integrate with surrounding surfaces. The decision to restore must be made carefully, but 3D scanning provides a valuable common foundation for discussion.

Use 5: Record including surrounding topography and spatial relationships

The value of stone structures is often inseparable from their installation site and surrounding environment. Unlike artworks preserved in isolation, stone markers on approach paths, stone lanterns in precincts, groups of graveyard stone pagodas, retaining stonework on slopes, and stone structures forming parts of sacred spaces have meaning that includes their surroundings. 3D scanning is well suited to recording these spatial relationships three-dimensionally.

For example, even if you acquire the single object at high precision, if you do not know surrounding ground slopes, drainage paths, or distances to adjacent structures, analysis of deterioration causes or safety may be inadequate. A 3D record that includes surrounding topography lets you evaluate whether rainwater tends to pool, whether vegetation is close enough for root impact, or whether there is a contact risk from pilgrim or tourist flows—factors important for management.

When groups of stone structures have collective value, their mutual positions and sightlines are important. Being able to confirm in three dimensions from which directions axes align, how they are arranged relative to elevation differences, or how much they have changed due to later alterations is a major advantage. Three-dimensional records reveal height differences and sightlines not apparent in plan views, improving the accuracy of preservation planning.

Recording surroundings also supports future verification of environmental change. For example, if approach paving is renovated, drainage equipment is updated, trees grow, or nearby structures are added or altered, having recorded the surroundings makes it easier to trace how such changes affected the stone structure. Understanding change in the object requires a perspective that also considers changes in surrounding conditions.

In practice, it is common to think “it’s fine to just capture the object,” but that approach is insufficient for stone structures. Recording the place together with the object produces data useful across preservation, restoration, and exhibition stages.

Use 6: Smooth sharing of survey results and consensus building

Conservation and restoration of stone structures typically involve multiple stakeholders: surveyors, managers, designers, contractors, cultural property officials, and local community members. Therefore, sharing the current state and issues in a way that creates common understanding is extremely important. 3D scan data is excellent as explanatory material for this purpose.

When conveying the condition of a stone structure to people who have not seen the site directly, a few photos and text are often insufficient. Photographs and descriptions may not convey sense of scale, degree of tilt, location of losses, or relationships with surroundings, leading to inconsistent judgments. Visualizations, cross-sections, and viewpoint-changed images created from 3D data are easier for non-specialists to understand and increase the efficiency of discussions.

Especially when explaining the need for restoration, objective evidence is required. Concrete demonstration of shape displacements, component shifts, or plinth irregularities is more likely to gain understanding than simply saying “it’s dangerous” or “it’s deteriorated.” This is also effective for budgeting and prioritization. When explaining where to allocate limited resources, organizing based on three-dimensional data is persuasive.

In pre-construction meetings, 3D scanning helps prevent misunderstandings. It facilitates sharing of complex shapes hard to depict in drawings and conditions on unseen backsides, reducing rework caused by incorrect assumptions. As a result, on-site decisions stabilize and work quality becomes more consistent.

Stone structure conservation is highly specialized yet ultimately requires the agreement of diverse stakeholders. 3D scanning functions as a bridge. Viewing it not only as a survey technique but also as a communication foundation broadens perceptions of its benefits.

Use 7: Deploy for exhibition, public display, and educational outreach

3D scanning of stone structures has great potential not only for preservation and restoration but also for exhibition and education. Three-dimensional data allows many more people to appreciate stone structures that can only be seen by visiting the site or are difficult to approach for preservation reasons.

For example, using the three-dimensional shape of a stone structure to create videos and explanatory materials can clearly show surface ornamentation, inscriptions, and structural features. Details easily missed by the naked eye become easier to understand with magnification and viewpoint changes. This works for public exhibits, school education, community learning, and outreach promoting conservation activities.

3D data is also useful when on-site access is restricted. Stone structures located in unstable ground, sites with large elevation differences, or places where proximity must be limited for preservation may not be safely viewable by everyone. Public display using 3D data improves accessibility. It expands opportunities for the elderly, distant residents, and learners who cannot visit in person.

In exhibitions and outreach, the goal is not merely to create attractive visuals but to convey “why we protect these things.” Visualizing pre- and post-scan comparisons, deterioration progression, and restoration rationale helps communicate the significance of conservation activities. Stone structures are often close at hand yet not fully appreciated. Showing the complexity of shape, workmanship, and relation to installation environment in three dimensions can deepen recognition of them as regional assets.

The purpose of public use is to return survey findings to society and to share the need for preservation. In that sense, 3D scanning is an effective medium connecting practice and outreach.

Use 8: Establish a recovery foundation for disasters and accidents

Stone structures are often outdoors and exposed to various risks: earthquakes, heavy rain, landslides, fallen trees, vehicle impacts, and tipping accidents. If damage occurs and the importance of records is recognized only afterward, it is difficult to accurately restore the lost original state. That is why peacetime 3D scanning becomes the basis for disaster response.

In post-disaster recovery, how well you understand pre-disaster shape and positional relationships is crucial. Even if stone pieces fracture, components scatter, or plinths shift, prior 3D data make it easier to consider responses by referring to original shapes and arrangements. This is useful not only for emergency measures but also for full-scale restoration.

For stone structures at risk of theft or unlawful relocation, three-dimensional records of distinctive shapes assist identification. Surface damage patterns, inscription locations, and breakage characteristics are important individual markers. Used alongside photographic records, 3D data improves accuracy of locating and matching objects.

From an accident-prevention perspective, recording current tilts and distances to surrounding circulation lines for stone structures prone to tipping or located near pedestrian routes has value. These records support decisions on preventive measures and are useful for post-incident analysis. While 3D scanning alone cannot complete safety measures, its value as objective current-state evidence is high.

Disaster response effectiveness depends not only on initial actions after an event but also on readiness during normal times. 3D scanning of stone structures is not merely static preservation documentation but a risk management foundation. Though it is difficult to completely prevent damage, having records dramatically affects the quality of subsequent responses.

Perspectives for successfully implementing 3D scanning of stone structures in practice

3D scanning of stone structures is a powerful technique, but value is not guaranteed simply by adopting it. To realize practical outcomes, it is important to clarify “for what purpose the data will be acquired.” Required accuracy, scope, and representation methods differ depending on whether the objective is preservation records, restoration planning, temporal comparison, or public use.

For example, if the goal is precise single-object shape recording, you need a design that captures surface details thoroughly. If the focus is on spatial relationships and topography, broad-area acquisition including surroundings is essential. For comparative observation, consider standards that make future consistent acquisitions easier. In short, defining the intended use of deliverables comes before choosing equipment or methods.

It is also important to devise ways to avoid overlooking areas during acquisition. Backsides, undersides, shaded parts, areas hidden by vegetation, and interfaces with surrounding plinths are easily noticed as omissions afterward. Because frontal views alone often fail to capture the essence of stone structures, plan recordings with awareness of shape continuity. In one-off pre-restoration surveys, assume that retakes may not be possible.

Post-acquisition organization is also critical. If file names, acquisition dates, object names, location information, surrounding conditions, and links to photographs are not organized, future reuseability declines. 3D scanning is not “shoot and done”; the workflow includes making records usable and preserving them. In cultural property work, preservation periods are long, so storing them in a way future custodians can reference is essential.

Furthermore, positional accuracy in surveys affects practical value. Beyond precision of the single-object model, knowing where, at what elevation, and in what orientation it existed makes management considering surrounding context easier. Position information supports restoration, relocation, temporal comparisons, and coordination with surrounding works.

For practitioners seeking to improve on-site recording accuracy, combining iPhone-mounted high-precision GNSS positioning devices like LRTK is an effective idea. When 3D scan data of stone structures can be handled together with accurate on-site positional information, it becomes easier to establish a practical and reusable recording foundation across preservation, restoration, management, and exhibition workflows.

Summary

3D scanning of stone structures is not merely an advanced recording technology. It is a practical foundation that links baseline preservation records, deterioration comparison, restoration planning, loss assessment, recording of surrounding environment, consensus building, exhibition/public use, and disaster recovery preparedness. Because stone structures have complex shapes, are subject to outdoor environmental change, and are often integrated with their sites, three-dimensional comprehension is particularly effective.

For practitioners, the key is not to make 3D scanning an end in itself. By clarifying which issues to solve and in which situations the data will be used, and by designing the required accuracy, scope, and recording methods, the data can become a living asset. Preserving stone structures is about carrying the current state into the future; in raising recording accuracy and reusability for that purpose, 3D scanning is an especially compatible means.

When recording stone structures on site and including their positional relationships with surroundings, not only shape data but also positional certainty is important. If you want to link survey results to maps, drawings, or other survey outcomes, thinking through acquisition of positional information expands possible uses. For practitioners aiming to improve on-site recording accuracy, combining a high-precision GNSS positioning device attachable to an iPhone—such as LRTK—is a useful approach. If 3D scan data of stone structures can be managed together with accurate on-site position information, it becomes easier to create a more practical, reusable recording foundation across preservation, restoration, management, and exhibition.