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The M’Hamid Oasis is the last of the palm groves in the Drâa Valley, in Southern Morocco. The 13 villages (ksar/ksour in Arabic) in M’Hamid share many sociological, urban, and architectural similarities with the ksour located in the pre-Saharan valleys. These similarities range from environmental threats, such as extreme climate, to the current social and economic model. As a result, the settlements are being abandoned, and the tangible and intangible heritage of the Drâa Valley is in a progressive disappearance. The paper aims to discuss these issues.

To deal with the complexity of this problem, a progressive approach beginning at the territorial scale must be developed. In this regard, a lasting solution can be found only by promoting development that integrates nature, culture, and architecture, as well as by finding a new balance of these elements within the current social and economic requirements.

This paper presents part of the research conducted by the team of the Terrachidia Association, which allows an overall understanding of the place. To this aim, the new social and economic context of the Drâa Valley is pointed out, as well as the characteristic features of M’Hamid architecture and urbanism. In this regard, the principles and requirements of its conservation are presented, and the project of the Terrachidia Association is also described. Finally, the project’s impact is assessed and the results of the set of interventions are evaluated.

Since 2012, the activity of the Terrachidia Association has focussed on the study, promotion, preservation, and restoration of the architectural and cultural heritage of M’Hamid. The main activity of the association focusses on the organization of workshops, which are attended mainly by university students and professionals from around the world.

In total, 13 workshops were organized since 2012, thanks to the engagement of the local population. In this period, around 300 participants from more than 15 different countries attended these workshops, working with approximately a 100 local craftsmen. All of them share a similar commitment to the work that Terrachidia is developing. These workshops allow the participants to know places and people in a way hardly achievable through conventional tourism. At the same time, this awareness is also achieved in the local population, and cultural exchange strengthens its identity.

The purpose of the workshops organized by Terrachidia is manifold, and the participants actively take part in the restoration works while they interact and exchange experiences with a reality that is generally unknown in western societies. The local population also benefits from this cultural exchange by strengthening their identity, which is linked to architecture, and demonstrating the economic possibilities of conservation through responsible tourism. And these aims are achieved through a self-managed project, which benefits all involved.

This paper aims to investigate and explain the dual fracture behaviour of PA12 specimens sintered by selective laser sintering (SLS) as a function of wall thickness and build direction with a powder mixture 30:70. To achieve this objective, research related to chemical, thermal and structural behaviours as a function of the input variables was carried out to describe and explain why ductile-fragile behaviour occurs during fractures under uniaxial tension manufactured via a methodology of material analysis and manufacturing processes.

The factorial design 32 relates the fracture of PA12 tensile specimens to the horizontal, transverse and vertical build directions at 2.0, 2.5 and 3.0 mm thicknesses, respectively. Fractographic images revealed the fracture surfaces and their dual ductile-fragile behaviour related to the specimens’ measured crystalline, thermal, surface and chemical properties.

The study showed that thermal property variables differ depending on the input variables. The wall thickness variable affected this morphology the most, showing the highest percentage of the ductile area, followed by the transverse and vertical directions. It was determined that the failure in the vertical direction is due to crystalline gradients associated with the layer-by-layer construction process. The pore density may be closely related to generating ductile and brittle areas.

In this paper, fracture characterisation is performed based on the mechanical, chemical, structural, thermal and morphological properties of PA12 manufactured by SLS. In addition, a heatmap of porosities in cross-sections is constructed using a machine learning model (k-means) related to dual fracture behaviour. This research revealed significant differences in the fracture type according to the build direction. In addition, thin-section fractography provides a more detailed explanation of the fragile behaviour of the vertical direction associated with crystalline changes due to the direction of the sintering layers.