Bibliographic research on historical documents from the archives of several national institutions, namely Direcção Geral dos Edifícios e Monumentos Nacionais, Torre do Tombo, Evora’s and Portalegre bishoprics, local museums and libraries in order to obtain information about the construction techniques, the provenance of the materials used for mortars, and the conservation and repair works preformed through the ages.
This data will be cross linked with data related to the history of the places and their social evolution.
Careful and correct sampling is of utmost importance to guarantee the success and representativity of the physical and chemical characterization studies. The choice of the sampling sites is done by a careful initial inspection of the buildings. The extraction operation will be well documented and registered before and after removal of the sample through acquisition of pictures and a description of the aspects observed.
In the laboratory, samples will be carefully observed under a stereomicroscope at low magnification to detect and register special features, such as fiber materials or ceramics, and to separate the different layers of the sample, for subsequent analysis.
The samples will be gently crushed with a rubber hammer and sieved to remove larger aggregate particles and then separated into several fractions that will be subjected in the next task to different protocol procedures.
The characterization methodology involves the use of several physico-chemical techniques, namely X-ray difractometry analysis (XRD), thermogravimetric and differential thermal analysis (TGA/DTA), optical microscopy (in reflection and transmition modes), scanning electron microscopy with an energy dispersive X-ray microanalysis system (SEM-EDS), atomic absorption spectrometry (AAS), potenciometry, gravimetry, capillarity water absorption, compressive resistance, mercury porosimetry and nitrogen adsorption. This methodology allows a great reliability in the final analysis, attempting to maximize the characterization objectives and, overlap, the techniques limitations.
Some research have been done and published in this area, nevertheless it is still necessary to systematize and complete the existing survey and to evaluate the present feasibility of materials and techniques used, considering present workmanship, work delays and economic factor.
Selection of materials, namely lime and aggregates, based on the results of previous tasks (3 and 4). A special care will be accorded to the choice of aggregates, their nature and grading, taking into account their influence on the porous structure of the material.
Preparation of specimens for physical and mechanical characterization: workability, density, capillarity, drying characteristics, compressive and flexural strength, elasticity modulus, water vapour permeability, accelerated ageing.
Detailed characterization by nitrogen adsorption and mercury porosimetry of the porous structure of historical and new compatible mortars.
Correlation of these results with results from task 3 in order to gain a better understanding about the chemical and structural transformations that occur during the process of mortar preparation and the importance of mortar composition and porous structure in the deterioration of masonry monuments and buildings.
Creation of a interactive webpage where it will be possible to find information about the history and conservation of the monuments, the project progress and results, and future research needs.
Diffusion of the published works.
In 2008 will be held a Congress with international and national researchers participation.