This paper describes the inspection for cavity detection in an urban area in Torrente (Valencia, Spain). A shallow cavity was found during excavation works for a sewerage project. Digging activities were stopped immediately and a GPR survey was required to reorganize the sewerage planning. The 3D GPR-mapping pinpointed cavities mostly on one side of the street. As a result, the sewerage system layout was moved to the side of the street where poor cavity evidences were detected. GPR technique is helpful for minimizing costs, time, work safety risks and inconveniences to neighborhood during civil engineering works, especially in urbanized areas.Highlights 1  3D GPR data has been used for cavity detection in urbanized areas. 2  3D representations of GPR data facilitate interpretation in civil engineering. 3  GPR survey reduces work safety risks in urbanized karst hazardous areas. 4  Civil engineering projects including GPR are cost-effective and time-reducing. Highlights Graphical Abstract Minimizing street work disruption by mapping cavities 1 derived from 3D GPR-data: a new sewerage project in 2 Torrente (Valencia, Spain) Abstract 13 This paper describes the inspection for cavity detection in an urban area in Torrente 14 (Valencia, Spain). A shallow cavity was found during excavation works for a sewerage 15 project. Digging activities were stopped immediately and a GPR survey was required to 16 reorganize the sewerage planning. The 3D GPR-mapping pinpointed cavities mostly on 17 one side of the street. As a result, the sewerage system layout was moved to the side of 18 the street where poor cavity evidences were detected. GPR technique is helpful for 19 minimizing costs, time, work safety risks and inconveniences to neighborhood during 20 civil engineering works, especially in urbanized areas.21 22 23 *Manuscript Click here to view linked References 2 Keywords 24 street work disruption; ground-penetrating radar; GPR; cavity; cave hazards; 3D 25 mapping; sewerage project 26 27 130 depth of 1.5 m projected excavation for sewer pipe. Amplitude slice maps from the 3D 131 model were used to identify irregularities at a constant depth. Besides, transparent 132 visualization of the 3D GPR data set was conducted for revealing main subsurface 133 anomalies. 134The main objective was to define the location, shape and depth of the cavities detected. 135The results can be enriched when visualized as a volumetric rendering. This procedure 136 allows anyone to reckon and understand how the subsurface area under study looks. 137 Maps and 3D representations allow for the characterization of the radar data, for 157 depth-slices are identified at 0.5, 1.0, 1.5 and 2.0 meter-depth. The maximum and 158 minimum amplitude ranges according to the amplitude-color scale characterize the 159 cavities filled with air in the subsurface study site. Moreover, the isosurface rendering 160 technique enabled visualizing the whole subterranean structures defined by karst

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Employers in the construction industry are regularly and increasingly reporting hiring difficulties, since the sector is experiencing a skills shortage in spite of numerous apprenticeship schemes. According to the European Construction Sector Observatory, the main reason of this skills shortage is two-fold: a) the inadequacy of VET provision, and b) the low attractiveness of the sector to young people, further hindered by the perception of its limited capacity for innovation. Correspondingly, modernising construction apprenticeships is crucial for the development of key skills and the improvement of the employability of young construction workers. Training the trainers and mentors to become more engaged and involved in the design of apprenticeships and to introduce new methods, digital tools, and innovative content during their teaching practices is essential to make training more flexible and effective. Such an approach could effectively address the misalignment between VET offerings and the demand for skills and innovation in the construction sector. This article shows the focus of the European project CONDAP, whose purpose is to improve learning in the construction sector.

The construction segment is an important economic sector in Europe, representing 9% of European gross domestic product (GDP) and providing approximately 18 million direct jobs. Construction activities that include renovation work and energy retrofits add almost twice as much value as the construction of new buildings, and small and medium-sized enterprises (SMEs) contribute more than 70% of the value added in the EU building sector. Furthermore, European legislation obliges member states to establish minimum energy efficiency requirements for buildings to achieve optimum levels of costs versus energy demand reduction. These requirements are reviewed every five years and represent categories of buildings based on their energy levels (demand and generation). This chapter analyzes the legislation associated to nearly zero energy buildings (nZEB) in Spain in order to identify the factors that will leverage their massive implementation.

The construction segment is an important economic sector in Europe, representing 9% of European gross domestic product (GDP) and providing approximately 18 million direct jobs. Construction activities that include renovation work and energy retrofits add almost twice as much value as the construction of new buildings, and small and medium-sized enterprises (SMEs) contribute more than 70% of the value added in the EU building sector. Furthermore, European legislation obliges member states to establish minimum energy efficiency requirements for buildings to achieve optimum levels of costs versus energy demand reduction. These requirements are reviewed every five years and represent categories of buildings based on their energy levels (demand and generation). This chapter analyzes the legislation associated to nearly zero energy buildings (nZEB) in Spain in order to identify the factors that will leverage their massive implementation.