The increasing commercialization of unmanned aerial vehicles (UAVs) has opened the possibility of performing low-cost aerial image acquisition for the documentation of cultural heritage sites through UAV photogrammetry. This paper presents two case studies that illustrate the use of the DJI Phantom 4 normal UAV for aerial image acquisition, and the results that can be achieved using those images. A general workflow procedure of oblique image capturing and data processing of large data sets has been illustrated in the Prince of Wales Fort case study to create photogrammetric models and to generate orthophotos for condition assessment applications. The second case study provides insight on the possibility of using UAVs for post-disaster documentation when the accessibility and the availability of high cost equipment is of major concern. The results that were obtained from UAV photogrammetry of Nyatapola Temple and Bhairabnath Temple in Taumadhi Square in Nepal, which were damaged by the 2015 Gorkha earthquake, are presented and discussed.

The current application of digital workflows for the understanding, promotion and participation in the conservation of heritage sites involves several technical challenges and should be governed by serious ethical engagement. Recording consists of capturing (or mapping) the physical characteristics of character-defining elements that provide the significance of cultural heritage sites. Usually, the outcome of this work represents the cornerstone information serving for their conservation, whatever it uses actively for maintaining them or for ensuring a posterity record in case of destruction. The records produced could guide the decision-making process at different levels by property owners, site managers, public officials, and conservators around the world, as well as to present historical knowledge and values of these resources. Rigorous documentation may also serve a broader purpose: over time, it becomes the primary means by which scholars and the public apprehends a site that has since changed radically or disappeared. This contribution is aimed at providing an overview of the potential application and threats of technology utilised by a heritage recording professional by addressing the need to develop ethical principles that can improve the heritage recording practice at large.

The increasing commercialization of unmanned aerial vehicles (UAVs) has opened the possibility of performing low-cost aerial image acquisition for the documentation of cultural heritage sites through UAV photogrammetry. The flying of UAVs in Canada is regulated through Transport Canada and requires a Special Flight Operations Certificate (SFOC) in order to fly. Various image acquisition techniques have been explored in this review, as well as well software used to register the data. A general workflow procedure has been formulated based off of the literature reviewed. A case study example of using UAV photogrammetry at Prince of Wales Fort is discussed, specifically in relation to the data acquisition and processing. Some gaps in the literature reviewed highlight the need for streamlining the SFOC application process, and incorporating UAVs into cultural heritage documentation courses.

Purpose: The purpose of this paper is to discuss the application of documentation and recording techniques for World Heritage conservation using the case studies of the Petra Archeological Park (PAP) in Jordan and the Silk Roads Cultural Heritage Information System (CHRIS) in Central Asia. In the PAP case study, these techniques could aid in the assessment of risks faced by World Heritage properties and threats to the integrity of the Outstanding Universal Values (OUV). With respect to the Silk Roads CHRIS case study the Geospatial Content Management System (Geo‐CMS) proposed aims to improve information management and collaboration among all stakeholders.Design/methodology/approach: Integrated surveying techniques and information management systems together with active stakeholder participation can be used as conservation and management tools. In the case of PAP, using a systematic documentation tool (MEGA‐J) to conduct site condition and risk assessment of cultural heritage and combining photographs, maps and GPS measurements within a GIS platform allows for identifying the location and intensity of risks, and the degree of vulnerability within the PAP boundaries and buffer zone. In the Silk Roads CHRIS project the Geo‐CMS brings together data from different fields, e.g. geography, geology, history, conservation, to allow for a holistic approach towards documentation, protection and management of a number of diverse sites to be combined in serial transnational World Heritage.Findings: The study provides insight into how digital technologies can aid in heritage documentation and conservation, including stakeholder involvement and training. Moreover, by means of the two case studies it can be shown that a combination of digital technologies allows for an efficient mapping of buffer zones and risks and how a Geo‐CMS can form a common platform to manage large quantities of information of different origin and make it accessible to stakeholders in transnational projects.Originality/value: This paper discusses the use of digital technology and the participation of stakeholders in heritage conservation and documentation when dealing with complex World Heritage properties, e.g. serial transnational and archaeological ensembles at high risk.

This research presents a comprehensive nonlinear quasi-static seismic assessment of an unreinforced rubble masonry building, Bytown Museum in Ottawa, Canada, using discontinuum-based analyses. In the proposed modeling approach, non-uniform geometrical properties of rubble masonry walls are replicated via a group of rigid polyhedral blocks interacting along their boundaries based on the discrete element method (DEM). Once the adopted modeling strategy is validated, the nonlinear quasi-static analysis of the South and North façades of the Bytown Museum is performed. Special attention is given to the irregular block generation within the discontinuum analysis framework, where discrete element models are generated from high-resolution site recording data, representing the masonry morphology at a high level of detail. Then, the predicted collapse mechanisms from advanced computational models are further utilized to generate pre-defined macro-blocks in kinematic limit analyses, providing a simple alternative solution for seismic assessment. The results reveal the significant effect of openings and the construction technique (morphology) in unreinforced rubble masonry buildings that can play an important role in the structural capacity and behavior. Moreover, it is noted that DEM-based solutions provide lower seismic capacity compared to kinematic limit analyses. Finally, a noticeable sensitivity to the input parameters in the discrete element models is noted; therefore, characterization of material properties is necessary for reliable predictions.