Reaction to Fire of Existing Timber Elements Protected With Fire Retardant Treatments: Experimental Assessment

Fire safety is an important issue of building safety, especially when the building’s fire load contents enhance the risks of fire deflagration. When existing timber structures are involved, the most usual way to improve its reaction to fire is to treat wood with fire retardants. This study focuses on the surface protection of existing timber roof structures against fire, through the use of fire retardant (FR) treatments applied on site. An experimental investigation was carried out to study the effect of FR treatments on timber reaction to fire, with a special emphasis on timber members with biological deterioration and previously treated with preservative products. The behaviour and effectiveness of intumescent and non-intumescent treatments was also investigated. The study showed that the application of FR treatments improved the reaction to fire of timber, even in the presence of previous preservative treatments. However, the choice of the specific FR treatment should take into account the substrate conditions. In addition, test results suggest that protection systems involving multi layers (intumescent and non-intumescent) with different functioning modes each are likely to have a good global performance on the protection of timber elements against fire.     

A hypothesis on different technological solutions for outdoor and indoor Roman wall paintings

The determination of the chemical composition of different parts of wall paintings (pigments, mortars and binders) provides information about technology of preparation of an artefact. Herein, we present a multi-methodological characterisation of wall paintings from a Roman archaeological site in Cuma, focusing on differences between an indoor (domus) and outdoor fabrication (a temple, Tempio con Portico (TCP)). Both pigments, binders and mortars were studied via a combination of destructive/μ-destructive (mass spectrometry, ionic chromatography, ICP-based techniques) and non-destructive (Raman microscopy, small-angle neutron scattering (SANS) and X-ray diffraction) methodologies. Particularly, the systematic presence of dolomite only in mortars from TCP may suggest an intentional use of such limestone for the outdoor fabrication of public interest. Differences between TCP and domus are also related to the composition of the pigment binder. In particular, the detected binders (studied by LC-MS/MS and GC-MS) were proteinaceous in the case of domus (possibly egg and animal glue) and drying oils in the case of TCP. Ultimately, our multi-methodological study provides an overall picture of the material components of paintings from fabrications with different use, proposing a hypothesis on technological choices according to conservative and destination reasons.     

The Poor Law of old England: institutional innovation and demographic regimes

The striking improvement in life expectancy that took place in England between the Middle Ages and the seventeenth century cannot be explained either by an increase in real wages or by better climatic conditions. The decrease in the risk of utter destitution or of death from famine that was evident on the eve of the Industrial Revolution stemmed, in part, from institutional changes in the old poor law, which began to take shape and become effective early in the seventeenth century.     

Investigation of chemical changes in bone material from South African fossil hominid deposits

The bone fragments of the Australopithecus Africanus from the dolomitic cave in the Cradle of Humankind in South Africa have been studied by the use of several spectral techniques. The aim was to establish their degree of preservation and possibilities of inferring the life conditions from them. X-ray diffraction studies revealed the transformation of the mineral components partially into fluoroapatite form with addition of goethite, birnessite and quartz phases and with surprisingly well preserved collagen remains. Several important chemical elements were detected by using the electron (EPMA) and synchrotron-based X-ray fluorescence (XRF) microprobes. Among them, Sr and Zn were distributed in a way following the distribution of Ca, the main element of the bones. We suspect the immanent crystallographic substitution of Ca in this case in native bone. Iron followed the distribution of Sr but while Sr is distributed in a continuous way in more rigid locations, iron occurs mainly in the edge zones of the bones and in spot-like inclusions inside. Some part of the spots located in a very edge of bone is also filled with Mn and Cu. It suggests that the porosity and fracture of bones plays a more significant role in the localization of Fe, Mn and Cu. They also form a rigid thin layer (100–250 μm) avoiding further penetration. As (as AsO₄³⁻?) distribution pattern is unique and seems to occur in those locations where the concentrations of Sr are small. The conditions for bone penetration as determined from Eh-pH diagrams suggest that is rather impossible to preserve the organic matter in locations of Mn and also that Mn and Fe hardly can meet in the same spots.     

Closed Condominiums as Urban Fragments of the Contemporary City

Contemporary cities have witnessed the emergence of new real-estate products in which gated communities and closed condominiums (CCs) can be included. The proliferation of these urban products is worldwide, with similar patterns that are analysed in this paper according to five perspectives of analysis: physical, economic, social, political and cultural. These perspectives cross-cut some of the main issues of discussion of the contemporary urban debate associated with private residential developments. These developments seem to appeal to an increasing number of social groups and have been able to adapt to different planning systems. With a smaller scale, these developments emerged in Portugal in the form of CCs, and are analysed in a case study in Greater Oporto. The purpose of this paper is to present the Portuguese singularities of this phenomenon in comparison with the worldwide dimension. In our case study we find some important particularities strongly associated with the Portuguese planning system. Some of these particularities have negative impacts on the surrounding urban landscape. As a result, CCs demand specific planning policies to counteract the negative consequences they are likely to generate in local social and urban fabrics. In the absence of these policies, CCs, as well as other private residential developments, are likely to contribute further to an increasingly fragmented and divided urban landscape.