The Ksar of Kenadsa counts among the most important old cities of the south-west region of Algeria by its cultural and religious dimension, its architectural value and the extent of its urban influence. Ksar has long been held as a functional and culturally radiant regional centre for all the western part of the Maghreb. This formerly powerful and influential centre is a shadow of its former self and today forms one peripheral district of a much larger city. The Ksar district is deserted by its occupants and subjected to the process of degradation. In this area, the traditional architecture evolved from an empirical knowledge, particularly oriented to the realisation of comfort in the hot season. The comfort requirements have changed, and so has the current architectural design. The city's development follows the example of the northern cities, which have a different climate. This raises questions concerning how the current architecture addresses local climate conditions characterised by a long a...

This study investigates the effects of incorporating recycled coarse aggregates (RCAs) at different substitution rates on the mechanical and fracture properties of recycled aggregate concrete (RAC). Four concrete mixtures were prepared: a reference mixture using natural coarse aggregates (NCAs) and three RAC mixtures in which 30%, 60%, and 100% of the NCA mass was replaced with RCAs. The RAC mixtures were compared to natural aggregate concrete (NAC) in terms of compressive strength, splitting tensile strength, modulus of elasticity, hydration rate, water-accessible porosity, pore size distribution, post-peak behavior, and fracture energy. The results show that as the RCA substitution rate increases, the RAC porosity rises and its modulus of elasticity decreases. However, the compressive strength and splitting tensile strength remain comparable to, or even exceed, those of NAC, with optimal performance observed at a 60% substitution rate. This optimal behavior can be attributed to a more favorable pore distribution and an increased hydration rate. For an equivalent strength class, RAC with up to 60% RCA substitution exhibits post-peak behavior and fracture energy comparable to NAC. However, at a 100% substitution rate, the behavior becomes more brittle, and fracture energy decreases by 23.20%.