The Roman bridge of Alcántara is the largest in Spain. Its preservation is of the utmost importance and to this end different aspects must be studied. The most prominent is the assessment of its structure, and this is especially important as the bridge remains in use. This paper documents the way the assessment of structural safety was carried out. The assessment methodology of existing structures was applied. The preliminary assessment was based on bibliographic data and non-destructive techniques. The geometric data of the bridge were obtained by Terrestrial Laser Scanning (TLS), which made possible the analysis of its deformations and assessment of its structure. Ground-Penetrating Radar (GPR) was also used with different antennae to work at different depths and spatial resolutions with the aim of analysing structural elements. From the above information, the assessment of structural safety was made using the limit analysis method by applying the historical works carried out on it and those described in the regulation of obligatory compliance in Spain (IAP11), studying the sensitivity of safety to the most relevant parameters. The state of preservation and structural integrity of the bridge is discussed and conclusions are drawn on the areas of greatest risk and the bases for the following assessment phase of preservation of the bridge.

In green urban areas, the allergenic factor is important when selecting trees to improve the quality of life of the population. An application of laser imaging detection and ranging (LiDAR) in building information modelling (BIM) is the capture of geo-referenced geometric information of the environment. This study presents the process of digitalisation of a green infrastructure inventory based on the geolocation and bioparameters of the cypress species. The aerobiological index (I_UGZA) was estimated by developing green infrastructure BIM models at different detail levels and with a new BIM dimension (6D) for the urban environment. The novelty of the study is the modelling of urban information for evaluating the potential environmental impact related to the allergenicity of the urban green infrastructure using LiDAR through BIM. The measurements of cypress trees based on bioparameters and distances were applied to the I_UGZA. This innovation for describing the current 3D environments and designing new scenarios in 6D may prevent future problems in urban areas during construction projects.

Electrical risk has a particular impact within the construction sector. This leads to the development of regulations to mitigate it, but correct application of regulations is impossible with a traditional 2D analysis. The construction sector is using technologies from the industrial sector (Construction 4.0), with BIM as the main enabling technology. Thus, the objective of this article is the evaluation of the risk produced by Overhead Power Lines (OPL) through BIM integration. The OPL, its risk zones, the affected road, and the envelope resulting from the geometry of the necessary machines to build it were digitized, converging in a single model to perform a 4D risk analysis. The risks of the execution of the embankment and road surface of a road section passing through an OPL were analyzed by means of the collision of the envelope with its risk zones, resulting in an integration of their evaluation, to which was added the introduction of preventive measures and their re-evaluation. The parametric 3D modelling allowed a better definition of the risk zones and the BIM management minimized errors, providing traceability of decisions from the design phase, complying with health and safety regulations and applying the principle of Prevention through Design (PtD).