Advancements and Applications of Finite Element Methods (FEM) and Laser Scanning Documentation (LSD): A Systematic Literature Review

1.1 Background

Cultural heritage protection, interpretation, and management are essential for assuring its appreciation and understanding by present and future generations. This study presents a systematic review of the advancements and applications of Finite Element Methods (FEM) and Laser Scanning Documentation (LSD) within the domain of Cultural Heritage (Yang, Xu & Neumann 2014). A terrestrial laser scanner (TLS) is an optical instrument that creates detailed 3D representations of objects by generating dense point clouds in near real-time. This technology captures the external surfaces of physical objects and can provide additional data like reflectivity and color (Almac, Pekmeczi & Ahunbay 2016). Despite its high cost, TLS is widely used, especially in cultural heritage, where it helps document and monitor the condition of historic buildings and supports restoration efforts.

TLS allows for comprehensive coverage of structures, moving beyond traditional surveys that only capture specific sections (Castellazzi et al. 2015). It enables the integration of geometric and radiometric information to produce textured 3D models, which help to analyze conditions like moisture damage (Moyano et al. 2022). TLS can survey internal areas, making it valuable for damage assessments, like after earthquakes (Castellazzi et al. 2015).

Review was conducted through an extensive analysis of academic databases, encompassing research articles published between 2015 and 2023. The findings demonstrate that FEM and LSD have been instrumental in simulating and analyzing various physical phenomena, including structural stress, strain, and stability. The current study critically challenges the limitations associated with FEM and LSD, highlighting implications for future research directions. A particular focus is given to the academic utilization of Systematic Literature Review (SLR) in Cultural Heritage studies across diverse geographical contexts. The paper provides illustrative examples of its application in Cultural Heritage research and underscores its potential to enhance scholarly knowledge and inform best practices in heritage preservation and management.

1.2 Literature review

Bridges built of brick and stone represent a unique symbol of the local cultural heritage of the countries in which they were built. However, they are vulnerable to various natural and human-caused hazards that cause significant damage, sometimes irreparable (Azar & Sari 2023). Loads cause significant damage or collapse, necessitating their maintenance and preservation (Tapkın et al. 2022). Events such as floods and earthquakes have resulted in partial or complete destruction of these bridges. In response, repairs have been undertaken on historic arch bridges.

New technologies are positively influencing the restoration process, offering viable alternatives to traditional inspection methods that are often labor-intensive, costly, and unsafe. The role of non-destructive testing (NDT) is becoming increasingly important in these restoration efforts (Azar & Sari 2023). A numerical method for resolving issues that can be expressed as functional minimization or as partial differential equations is the Finite Element Method. Even with basic approximating functions, piece-wise approximation of physical fields on finite elements yields good precision (Nikishkov 2004).

FEM is a widely used tool for studying dynamic structural building behavior, providing valuable information for cultural heritage monument conservation. This method uses tools that generate a cloud that allows for the drawing of a structural map of the current damage to the building and any damage that may be expected in the future (Clementi et al. 2016).

The methods used to analyze and diagnose building structures are divided into three categories: destructive, semi-destructive, and non-destructive. The most useful Non-Destructive Testing (NDT) methods are Digital Image Processing (DIP), Photogrammetry (P) and Stereo Photogrammetry (SP), Laser Levelling (LL), Ambient Vibration Testing (AVT), Infrared Thermography (IRT), and underground mapping analysis by Ground-Penetrating Radar (GPR). These techniques help in designing the FEM methodology (Diz-Mellado et al. 2021).

These methods are used to build a 3D model. Modeling in 3D allows the study of an archaeological structure in all its metric and material specifications and volumetric organization. It also allows us to investigate reality over its contingent physical form (Campi, Di Luggo & Scandurra 2017).

Transforming a point cloud into a 3D model is a crucial research area, especially in cultural heritage, where complex structures or buildings are the primary focus. In the case of historical buildings with complex architecture, this is required (Alfio et al. 2024). The FEM approach is utilized to study mechanical properties of materials, including compressive strength, shear strength, and modulus of elasticity, and provides non-destructive testing and 3D visualization (Pirchio et al. 2021).

3D information enables morphological measurements, quantitative evaluations, and annotations of information. 3D data production is crucial for managing architectural heritage information, enhancing knowledge, and developing targeted conservation strategies. A successful information management plan considers three fundamental concepts: segmentation, hierarchical connection structuring, and semantic enrichment (Grilli & Remondino 2019).

3D architecture models have evolved into spatial metaphors, enabling information distribution in time and space and serving as an interface for data localization and retrieval. 3D model-based structured systems enable unprecedented studies in tasks like data storage and access, geographical analysis, and more. 3D semantic models, organized as cognitive systems, offer a semantic approach to traditional challenges in building design, management, and comprehension (Apollonio, Gaiani & Sun 2013).

To study the FEM methodology in detail, identify the gaps in this field, and study the future directions of research, it was decided to apply a systematic literature review (SLR) methodology, presented in the following section.

1.3 Systematic Literature Review (SLR)

Researchers aim to provide a thorough and unbiased account of the present state of knowledge in a specific topic by performing SLR, emphasizing gaps in research and recommending opportunities for further exploration. SLR has been increasingly used in cultural heritage research to discover and integrate existing knowledge on a topic or research issue. Systematic literature evaluations in this field have primarily focused on using 3D scanning, modeling, virtual reality, and augmented reality in cultural heritage preservation (Ferreira Lopes 2018; Khan et al. 2020; Bastem & Cekmis 2022). In the field of cultural heritage research, SLR has been used to explore a wide range of topics, not only including digital heritage (Ferreira Lopes 2018), but also heritage conservation (Davis & Heravi 2021), cultural heritage management (Li et al. 2020), and heritage education (Malegiannaki & Daradoumis 2017; Tavares, Alves & Vásquez 2021). Reviews in these areas have evaluated various methods, technologies, and policies, identifying both challenges and opportunities for future research and practice (Khan et al. 2020; Tavares, Alves & Vásquez 2021; Mendoza, De La Hoz Franco & Gómez 2023). SLR has been applied by Li et al. (2020), Trillo et al. (2020) and Mu and Aimar (2022) in specific fields of heritage conservation, focusing on topics such as the effectiveness of heritage conservation approaches, and the use of digital technologies in heritage conservation. It has been used in cultural heritage research to explore Cultural Heritage Management and policy issues. For example, reviews have examined the role of community engagement in heritage management (Ayala, Cuenca-Amigo & Cuenca 2020), the effectiveness of heritage education programs (Malegiannaki & Daradoumis 2017) and the impact of international conventions and agreements on heritage conservation (Siqueira & Martins 2022).

2.1 Methodology

The methodology of SLR was first adopted in the medical field in the 1970s (Gurevitch et al. 2018) and successively in other fields, such as social sciences, engineering (Orr, Richards & Fatorić 2021; Mu & Aimar 2022), and business and economics (Panchal, Singh & Diwan 2021; Silvestri et al. 2021). Review includes a systematic search approach, the definition of inclusion and exclusion criteria, and a critical assessment of the quality of research included in the study (Ritterbusch & Teichmann 2023). The purpose is to remove prejudice and ensure that all vital research gets examined, regardless of its conclusions or publication status (Silvestri et al. 2021). SLR findings inform policy, practice, and future research in a particular field. By synthesizing current information, significant discoveries and gaps in literature can be investigated before making recommendations for future research and practice (Ayala, Cuenca-Amigo & Cuenca 2020).

The most popular protocol for SLR among researchers is the “PRISMA” method (Preferred Reporting Items for Systematic Reviews and Meta-Analyses), a stepwise process that helps summarize existing literature. The PRISMA flow diagram records the different stages of the literature search process (Figure 1). Papers are selected after examining the literature (full text of the paper), determining the paper eligibility criteria (is this paper suitable in terms of quality, for example), and determining the inclusion criteria (is this paper, for example, written in English). The PRISMA approach is widely used and recommended as a methodology for performing and reporting SLR and meta-analyses (Peixoto et al. 2021). Authors increase the quality and transparency of their SLR by using the PRISMA checklist, making it easy for other researchers to judge the validity and reliability of their findings. In the current paper, PRISMA was used for systematic review.

Figure 1

The SLR analysis was performed using the academic databases Scopus, Web of Science and ScienceDirect. These were chosen because they cover many publications and citations (Briner & Denyer 2012; Ritterbusch & Teichmann 2023). Only journal publications were considered. Journals were preferred due to their rigorous peer review process, quality control, and accessibility, making them the most valuable sources for scholarly research (Adams, Smart & Huff 2017; Liang, Lu & Martin 2021). According to Briner and Denyer (2012), the following stages of SLR must be used in analysis:

1. Proper definition of a research question

2. Exploration and analysis of literature using ad hoc chosen keywords

3. Inclusion of papers that match research criteria and aims (fit-for-purpose approach)

4. Creation of a database in which papers and discoveries are examined and classified

5. Synthesis in which information from the database is extracted and debated.

2.2 Research Strategy

2.2.2 Material Collection

The first step was to clearly define the research question that the literature review will address (Munn et al. 2018): “what are recent advancements and applications of FEM and LSD in the field of Cultural Heritage?”.

The next step was to identify the relevant search terms for the literature search. For this step, keywords were identified and screened for articles to be included in the analysis (Mansuri et al. 2022).

A preliminary search was conducted using Google Scholar to identify the keywords that should be used in the search strings. Figure 2 shows the keywords used in the search strings.

Figure 2

We used filter tools to search strings within the Scopus, Web of Science, and ScienceDirect databases. Search strings were formulated without a specific time frame, and we focused on retrieving journal articles and reviewing articles exclusively (Table 1).

Table 1

Search strings used in Scopus, Web of Science, and ScienceDirect databases.

DATABASE	SEARCH STRINGS	NUMBER OF RESULTS	FILTER TOOLS
Scopus	“Finite Element Methods” AND “Laser Scanning” “Heritage bridges” AND “Laser Scanning” “Finite Element Methods” AND “Archeological sites” “Archeological Sites” AND “Laser Scanning” “Finite Element Methods” AND “Structural Health Monitoring” “Finite Element Methods” AND “Arches Bridges” “Arch” AND “Terrestrial Laser Scanning” “Arch” AND “Finite Element Methods”	3951	Year: until 2023 (the search start year was not specified, it was left open) Document type: article Subject area: Engineering Materials Science Physics and Astronomy Environmental Science Social Sciences Arts and Humanities Multidisciplinary Source type: journal English language
Web of Science	“Finite Element Methods” AND “Laser Scanning” “Heritage bridges” AND “Laser Scanning” “Finite Element Methods” AND “Archeological sites” “Archeological Sites” AND “Laser Scanning” “Finite Element Methods” AND “Structural Health Monitoring” “Finite Element Methods” AND “Arches Bridges” “Arch” AND “Terrestrial Laser Scanning” “Arch” AND “ Finite Element Methods”	1422	Year: until 2023 Document type: article, review article Subject area: Engineering Civil or Construction Building Technology or Materials Science Multidisciplinary or Engineering Multidisciplinary or Engineering Geological or Geosciences Multidisciplinary or Multidisciplinary Sciences or Environmental Sciences or Engineering Environmental or Metallurgy Metallurgical Engineering or Water Resources or Architecture or Green Sustainable Science Technology or Geology or Remote Sensing or Environmental Studies or Imaging Science Photographic Technology or Physics Multidisciplinary Source type: journal English language
ScienceDirect	“Finite Element Methods” AND “Laser Scanning” “Heritage bridges” AND “Laser Scanning” “Finite Element Methods” AND “Archeological sites” “Archeological Sites” AND “Laser Scanning” “Finite Element Methods” AND “Structural Health Monitoring” “Finite Element Methods” AND “Arches Bridges” “Arch” AND “Terrestrial Laser Scanning” “Arch” AND “ Finite Element Methods”	2653	Year: until 2023 Document type: research article, review article Subject area: Engineering Physics and Astronomy Materials Science Earth and Planetary Sciences Source type: journal English language

The present study considers all articles published before 15 August 2023. The study collected datasets from previously conducted systematic searches utilizing Scopus, Web of Science, and ScienceDirect (as displayed in Table 2). To ensure the integrity of the dataset, we manually removed duplicates. Pre- and post-deduplication statistics were obtained, comprehensively assessing the dataset’s content (Borissov et al. 2022). The database search yielded 8026 research papers. There was a significant amount of duplication because we used three databases. 1226 duplicates were excluded, resulting in only 6800 papers.

Table 2

Total number of papers after removing duplication between the results of the three databases.

DATABASE	NUMBER OF RESULTS
Scopus	3368
Web of Science	1239
ScienceDirect	2193
Total	6800

Articles were considered as evidence type (empirical/conceptual), literature review (descriptive or exploratory or mixed), research design (qualitative or quantitative or mixed), or research method (i.e., case study, experiment, causal, primary or secondary; (Mendoza, De la Hoz Franco & Gómez 2023).

2.2.4 Research Primary Process

To confirm the validity and safety of the search operations and the accuracy of the results, we conducted a preliminary search, using the keywords “archaeological conservation,” “arch bridge,” “finite element methods,” and “laser scanning.” The time was not specified, and the search was limited to documents published in scientific journals. To study the research density of countries, conducting a preliminary search is evidence of the objectivity and validity of the systematic review.

The previous process was done using VOSviewer, a software tool designed to create and visualize bibliometric networks. Researchers utilize VOSviewer to analyze bibliographic data from databases like Web of Science and Scopus (Bukar et al. 2023). A key feature of VOSviewer is its ability to cluster network elements based on their similarity. Its clustering capability aids in understanding the underlying structure of the research subject and in identifying emerging themes (Van Eck & Waltman 2010).

The results of our primary research were consistent with (Van Eck & Waltman 2010; Orr, Richards & Fatorić 2021). These results indicate the countries currently conducting research and contributing most significantly to the development of this field: Italy, Canada, Poland, Spain, Germany, Austria, Portugal, and England. Figure 3 shows the countries with the highest research intensity identified.

Figure 3

Figure 4 illustrates the extent of research collaboration among researchers across various countries. It highlights a substantial lack of interconnectedness among researchers, which can be attributed to language barriers arising from distinct official languages in each country. The curved lines in Figure 4 represent the strength of research ties between the most research-intensive countries.

Figure 4

Bibliometric networks reveal the paucity of scholarly endeavors in laser scanning worldwide, with a notable concentration of research observed in Italy. This concentration can be attributed to Italian researchers’ widespread utilization of laser scanning technology.

3.1 Descriptive Analysis

Italy has the highest number of publications, with 14 articles, followed by Spain and Turkey. European countries have the highest number of publications in this field, with 40 out of the 60 papers included in this review. The review also covers other countries, including the United States, South Africa, and Latvia. Figure 5 indicates that the study of the use of FEM and LSD methods in cultural heritage is still an emerging field.

Figure 5

There has been a significant increase in the number of articles published since 2009, showing clear signs that this research topic is starting to gain traction and interest from researchers and is likely to continue to grow in terms of number of articles and publications (Figure 6).

Figure 6

The largest publication venue was the journal Remote Sensing, with six papers, followed by Engineering Structures and the Journal of Cultural Heritage, with five papers. All analyzed journals are rated Q1-Q4 in the Scimago Journal & Country Rank (SJR). Publications reviewed for the current paper were predominantly case study papers, investigating applications of FEM and LSD in Cultural Heritage conservation in different cultural heritage sites. There were also a notable number of studies classified as review papers. These publications are improving and enhancing management and conservation practices for cultural heritage (Orr, Richards & Fatorić 2021).

Most publications in this study have low citation rates with three or fewer average citations each year (Kęsik et al. 2022). This is due to the wide variety of academic fields and publication sources, making it difficult for researchers to identify and cite relevant research (Orr, Richards & Fatorić 2021). There is a scarcity of researchers specializing in FEM in the field of archaeology, as FEM is an approach used in engineering applications (surveying and civil engineering), and the application of this methodology requires an archaeologist with an engineering background. Of the three most cited papers, three were reviews or conceptual papers:

• “Cloud-to-BIM-to-FEM: Structural simulation with accurate historic BIM from laser scans” (Barazzetti et al. 2015), with 209 total citations.

• “An innovative numerical modeling technique for structural investigation of monumental old structures” (Castellazzi et al. 2017), with 205 total citations.

• “From laser scanning to finite element analysis of complex buildings by using a semi-automatic procedure” (Castellazzi et al. 2015), with 163 total citations.

It is also possible that the citation rate is low because the methods are new and not yet popular among researchers.

The number of cited articles peaked in 2017 and 2023. This recent increase demonstrates a growing interest in using modern technological techniques in archaeological research.

There were mainly three articles: quantitative, qualitative, and mixed. There were also two descriptive studies, 29 exploratory studies, five casual studies, and 34 mixed studies. Table 4 shows the classification of articles in the systematic review by type of research approach.

Exploratory research is more popular, which means that experimental studies are still being carried out, analyzed and explored by researchers. Exploratory research helps researchers gather original data for their studies. It highlights the importance of exploratory research as a precursor to further studies, while primary research is necessary to gain new insights that advance understanding in different fields.

3.2 Quality Assessment

SLR involves assessing the quality or bias in the included studies, thus enhancing the objectivity of quality assessments. Our study evaluated quantitative and qualitative research articles using custom-designed tools, based on established standards. For qualitative research, we utilized a tool consisting of 16 questions derived from the Qualitative Research Review Guidelines (RATS) checklist (Smith et al. 2018). After assessing the quality of the articles, the average number of positive answers was 12.3 out of 16 (76.875%). In qualitative research, research questions hold paramount importance as they guide entire studies, distinguishing it from quantitative research that is guided by predetermined hypotheses. The EPHPP Quality Assessment Tool for Quantitative Studies is a commonly used tool for evaluating quality, providing a structured approach to assess methodological strengths and weaknesses to judge the study’s reliability and validity (Ravensbergen & El-Geneidy 2023; EPHPP 2025). After assessing the quality of the articles, the average number of positive answers was 10.10 out of 12 (84.17%). This result indicates that the quality of studies is sufficient.

3.3 Coding Framework, Thematic and Content Analysis

Thematic analysis, an inductive method, involves moving specific content within data to generalize and develop theoretical frameworks. It links identified themes with underlying data through coding, categorization, and pattern recognition, revealing themes at different analysis levels (Qiuxia, Abdul Rahman & Wenhong 2022). Research focus in literature indicates current trends and patterns in disciplines. The content of the manuscripts is analyzed, and the topics under which they fall are identified. Similar manuscripts are then grouped under a single thematic heading. This method is useful in identifying current and future trends in academic research in a particular field of study or research.

For thematic analysis, we used the MAXQDA program and manual coding to analyze articles (Elaldi & Yerliyurt 2017). Through this process, we extracted linguistic connections and conceptual frameworks, linking them together to gain detailed data for content analysis and thematic analysis. The methods utilized allowed for the extraction of articles’ results, data analysis, and topic categorization, focusing on content related to Laser Scanning and Finite Element Analysis. Essential data analysis components in thematic analysis included coding, organizing codes into potential subthemes or themes, and comparing coding clusters internally and over the entire dataset (Vaismoradi et al. 2016).

Academic literature on thematic design revealed several central themes. The original coding yielded 15 characteristics; however, this was reduced to just seven themes after merging and renaming.

Primary data analysis output, known as a ‘Theme,’ encompasses practical outcomes derived from the study’s findings. Also categories are theme descriptors (Vaismoradi, Turunen & Bondas 2013). The themes assign meaning to categories and encompass subcategories that further elucidate the category’s significance (Qiuxia, Abdul Rahman & Wenhong 2022 This initial phase encompasses three key stages: “reading and identifying meaningful segments in transcriptions”, “coding and identifying abstract concepts within participants’ accounts”, and “documenting reflective notes.” In qualitative research methodologies, coding serves as a means of data reduction and is an integral part of organizing data (Alhojailan 2012). Table 5 shows the steps we took to perform thematic analysis.

The thematic category studies discuss various studies that focus on utilizing different modeling techniques, including converting point clouds into finite element meshes and creating Building Information Modeling (BIM) models, significantly reducing modeling time. Digital photogrammetry and laser scanning systems were employed for archaeological site documentation, producing orthophotos and 3D point clouds. Different scanners were compared for documentation purposes. Other studies presented an integrated approach for threat assessment and damage identification in vulnerability-sensitive areas, mainly focusing on the impacts of flooding and earthquakes on archaeological sites. Deformations, stresses, and vulnerabilities under dead loads and earthquake responses were investigated. Mathematical models of bridges were constructed for dynamic analysis using the Finite Element Method. Finally, surveys using UAV and TLS technology provided significant information for evaluating site damage, including these articles (Castellazzi et al. 2015, Pieraccini et al., 2014; Rüther et al., 2009, Teza & Pesci 2013, Ergincan et al. 2010; Tapete et al. 2013, Gonen et al. 2013; Fortunato, Funari & Lonetti 2017, Xu & Yang 2018 and Hu et al. 2023, Almac, Pekmeczi & Ahunbay 2016; D’Altri et al. 2023, Andreou et al. 2017; Brumana et al. 2018). Content analysis of the articles revealed that researchers focused on surveying and imaging technologies, like use of advanced surveying equipment and drones, and the use of advanced simulation software to create point clouds and study structures and bridges through models exported from simulation software.