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Volcanic structures are inhomogeneous on a number of scales. Quantifying whether such inhomogeneities result in a physical and mechanical anisotropy is important to improve large-scale volcano and volcano-geothermal modelling. It is, however, currently challenging to account for such anisotropy because there are very few experimental studies that quantify the physical and mechanical property anisotropy expected for volcanic rocks. Here, we measure the porosity, permeability, P-wave velocity, thermal properties, uniaxial compressive strength (UCS), and static Young's modulus of samples from five trachyandesite lavas from the Chaîne des Puys (Massif Central, France) that have been cored in three arbitrary orthogonal directions. We show, using X-ray computed tomography, that the pores in the most anisotropic lava are oblate spheroids, with a major axis 2−5 times larger than their minor axis, that have a shape preferred orientation. This lava is an order of magnitude less permeable, has a P-wave velocity ~25% lower, and has a UCS and Young's modulus ~50% lower when measured perpendicular to the major pore axis. The observed physical and mechanical anisotropy is therefore the result of a pore shape preferred orientation. We conclude that, alongside large-scale sources of anisotropy such as stratified lavas, modellers should also consider incorporating a physical and mechanical anisotropy in the volcanic rocks forming a particular layer in the development of models that seek to incorporate greater complexity. Incorporating additional complexities in modelling, where and when possible, will provide the most accurate predictions and therefore the most reliable information for a given volcano or geothermal reservoir. [ABSTRACT FROM AUTHOR]

The use of bio-based building materials is a sustainable opportunity to reduce the environmental footprint associated with the construction sector. The achievement of this objective is primely achieved through the valorisation of vegetable waste, resulting in a reduction in the use of primary source material and waste generation. Within the scope of this study, the focus is directed towards research concerning the thermal, acoustic, and fire behaviour properties of bio-based building materials. This study conducts a comprehensive bibliometric analysis encompassing all documents meeting these criteria within the Scopus database, spanning two decades, from 2003 to 2023. The comprehensive analysis covered a total of 1081 documents, which were analysed. This analysis furnishes insight into various facets, including the temporal evolution of publications, journals boasting the highest publication counts and impact, influential research areas, countries with substantial contributions and their collaborative patterns, noteworthy affiliations, prolific authors, and seminal documents, alongside recurrent keywords. The objective of this comprehensive study is to provide a detailed analysis of the documents published up to the present day, in order to identify research gaps and potential opportunities in this field, to assist new researchers interested in the subject. The analysis reveals that bio-based building materials have gained substantial attention over the past decade. With each passing year, the published documents have increased their impact and become more specific, underscoring the growing importance of this subject. This evolution has also fostered a broader network of researchers engaged in this field. However, it is noteworthy that the characterization of these materials focuses predominantly on their thermal properties, while research avenues related to acoustic and fire properties remain less explored and present opportunities for future investigation. • This study contributes to identify research gaps and potential opportunities in the field of bio-based building materials. • Studies in bio-based building materials have shown an annual growth of the 25% since 2014, being a topic on the rise. • France and China are the countries with the highest scientific publication on bio-based building materials. • Keywords play a crucial role in making visible the research within bio-based building materials. • "Thermal Conductivity" and "Thermal insulation" are the most repeated keywords in this field. [ABSTRACT FROM AUTHOR]