Current Problems Involving the Dismantle of Asbestos- Cement Sheets in Buildings. The Case of Central Market in Alicante

The project and the works described in this article mainly deal with the removal of the current asbestos-cement covering of the roof of the Central Market in Alicante and its replacement with zinc diamond-shaped scales, similar to the originals which were implemented in 1921 when the building was put into service. These upgrades were necessary to avoid the causes (and consequences) of rainwater infiltration, as described in an earlier report in 2006, also drafted by the author of this article. The article illustrates the difficulties involving the practical application of Spanish Code RD 396/2006 (minimum safety and health requirements for work with risk of exposure to asbestos) in a complex case such as this, especially with regard to aspects such as economic (increasing costs), technical (increased difficulty of implementation), and the total duration of the work (total increase in duration due to interference with other trades).

Self-sensing properties of alkali activated blast furnace slag (BFS) composites reinforced with carbon fibers

In recent years, several researchers have shown the good performance of alkali activated slag cement and concretes. Besides their good mechanical properties and durability, this type of cement is a good alternative to Portland cements if sustainability is considered. Moreover, multifunctional cement composites have been developed in the last decades for their functional applications (self-sensing, EMI shielding, self-heating, etc.). In this study, the strain and damage sensing possible application of carbon fiber reinforced alkali activated slag pastes has been evaluated. Cement pastes with 0, 0.29 and 0.58 vol % carbon fiber addition were prepared. Both carbon fiber dosages showed sensing properties. For strain sensing, function gage factors of up to 661 were calculated for compressive cycles. Furthermore, all composites with carbon fibers suffered a sudden increase in their resistivity when internal damages began, prior to any external signal of damage. Hence, this material may be suitable as strain or damage sensor.