Combined In-Situ and Laboratory Minor Destructive Testing of Historical Mortars

ABSTRACT

Mortar is of all masonry components the most difficult to be experimentally characterized in heritage buildings. This article investigates the possibility of combining different in-situ and laboratory minor destructive testing (MDT) techniques to assess the strength of mortar in historical brickwork. Lime mortar and clay brick walls were built in the laboratory and then tested in order to derive empirical correlation rules among three different MDT techniques: double punch test (DPT), helix pull-out test (HPT), and pin penetration test (PPT). The outcomes of this activity were used eventually to assess the mortar properties of an important historical heritage structure, Casa Puig i Cadafalch, located near Barcelona. The research is intended to promote the use of MDT in studies and conservation works on built cultural heritage by providing criteria for the evaluation of the strength of existing mortar with respectful sampling and testing techniques.     

黄色纳米比亚 穿越沙漠看海豹

如果在非洲看见一只斑马从眼前闪过或一队大象过马路,可能没人感到惊讶,可如果看见的是成群的海豹,多少让人觉得新鲜。     

Arnold J. Toynbee’s Quest for a New World Order: A Survey

This article surveys the work of the controversial historian and internationalist Arnold J. Toynbee (1889–1975). In particular, it examines Toynbee’s understanding of foreign politics and his constant search for a stable world order. From the idealism of his youth, through his temporary disenchantment with his youthful expectations, to the religiously inspired utopianism of his final years, this essay discusses the development of Toynbee’s work and understanding of international affairs throughout the twentieth century.     

Firing technique characterization of black-slipped pottery in Praeneste by low field 2D NMR relaxometry

This study was aimed at individuating characteristics related to the pottery’s firing technique of Classical Roman producers, through the low field single-sided NMR relaxometry. The approach is based on a recent method of analysis, the correlation of the longitudinal and transverse NMR relaxation times of a liquid probe (in this case distilled water) filling the porous system of ceramics. The analyzed findings form two homogeneous classes with dating and place of production well established through the producer trademarks. Pottery findings belong to the black-slipped pottery productions of the Latin ancient city of Praeneste between third and second century B.C. and have been attributed to two different ”patriziae” production families: gens Samiaria and gens Trebonia. A further fragment with Greek kylix style, found in the same archaeological area, has also been analyzed, in order to understand if it had been imported from Greece, or made in Praeneste in imitation of the Greek style.