Advanced Materials Research Vols. 133-134

Abstract: The Franciscan church of La Peregrina in Sahagún (Spain) was founded in the 13th Century. It has undergone many transformations and additions throughout its history. The most important were carried out in the 17th Century when the church was converted to the Baroque style. The apse vaults were demolished and new timbrel vaults were built hiding the Mudéjar windows. In the nave, the transverse arches that supported the modern roof were also demolished, internal counterforts were built and new barrel timbrel vaults with lunettes, erected. Eventually, an oval dome was built on the transept. Recent restoration work will give the building a new use. The project aims to recover the Mudéjar apse with its windows providing natural light to the presbytery. This involves the demolition of the Baroque vaults above the presbytery (a barrel vault terminated with a semi-dome). The oval dome will lose some buttressing to the side of the apse and an expertise was required to assess the feasibility of the operation. In the present paper the structure of the church will be described and the analysis of the oval dome with and without the presbytery vaults will be explained.

Abstract: During a scientific research, directed to understand the structural role of some particular masonry elements, noticeable in covering structures like vault and dome, we searched the technical rules and function of these elements. We verified that in literature there is no specific documentation about these elements and its mechanic purposes. The study was directed to recognize the most representatives architectures in different ages, and to identify the construction technique’s evolution process of this particular arc-double or thickening of arc that we arrived to identify as a necessary building component to give balance in particular structural configuration. This process put down roots from the roman ancient age, until baroque age, where the most original applications of this regulation were placed. From Pantheon to the limit case of St. Filippo Neri chapel, the covers’ structures springer angle studied was analyzed together with its relation to plan, sections and elevation of all buildings. Therefore, if these elements are well-performed, they follow precise constructive patterns that this article would like to identify and show.

Abstract: Whenever interventions on medieval churches are necessary, they must be approached as a whole, based on a numerical analysis of the load-bearing structure, especially if exceptional actions, like seismic ones, are present. Numerical analysis results can be successfully used in the assessment of quantitative elements for timber load-bearing structures. Nonetheless, masonry load-bearing subunits are more difficult to design and assess, results of the calculations made in case of elastic behaviour of the masonry structure being valid only until the first cracks. Numerical analysis can indicate, from a qualitative viewpoint, the behaviour of load-bearing structures of church buildings.. This paper presents the modelling principles of various types of load-bearing structural units belonging to medieval churches, which are subjected to dead loads and non-gravity actions, including Lutheran Church in Bistrita, Reformed Church in Aiud, Lutheran Church in Drauseni. , drafted within the Built Heritage Conservation Research and Design Centre – Utilitas, Cluj-Napoca City. It applies to three case studies, displaying their structural behaviour and contributing to the selection of appropriate strengthening methods

Abstract: Historical masonry buildings located in the Southern Italy are usually built with irregular stones joined with mortar with poor mechanical properties. Therefore, piers and spandrels ultimate resistance is not always well predicted by simplified formulas suggested by codes of practice, which typically are tailored to regular patterns. In this framework, we present a two-step numerical model –within the equivalent frame approach assumption– for the pushover analysis of in-plane loaded historical masonry walls constituted by an irregular assemblage of stones. In Step I, ultimate bending moment-shear force strength domains of piers and spandrels are derived by means of a heterogeneous upper bound FE limit analysis and the results are stored in a database. Assessing the capacity of both piers and spandrels is crucial for correctly predicting the ultimate resistance of masonry walls acted upon by in-plane loads. Heterogeneous limit analysis is particularly suitable for computing failure loads, since it permits a distinct modeling of stones and mortar joints. Appropriate static and kinematic boundary conditions are set to account for the complex interaction of internal forces and deformed shapes of single elements. At Step II, a frame model of the masonry wall is assembled, where piers and spandrels are modeled as elastic Timoshenko beams. At each analysis step it is checked that the internal forces in each structural element are smaller than the failure loads stored in the database created at Step I. If the capacity is exceeded, suitable flexural hinges are introduced at the end of the structural elements. The resistance of the element is then set to zero when a limit chord rotation is exceeded. With the numerical tool developed, a real scale old masonry oil-mill located in the Southern Italy is analyzed in the inelastic range under increasing static loads.

Abstract: For safety assessment, a double curvature hollow bricks cloister vault with lunettes has been studied. Its geometry, constructive aspects, crack pattern have been surveyed and a 3D finite element analysis has been carried out, the numerical model exploiting the accurate survey of the vault geometry.

Abstract: The internationally acknowledged Art Nouveau architect Victor Horta built remarkable artifacts of public iron architecture in Brussels. His projects display an innovative philosophy based on apparent iron frameworks used in a very efficient manner. As a supplement to the ample historical and architectural studies on Belgium’s most famous Art Nouveau architect, this paper puts Horta’s innovative structural practice of iron into the picture. To reach this goal, a structural analysis of four of Horta’s most interesting projects is carried out, going into the following topics: conceptual philosophy (structural typology), building techniques (shapes, connection details) and the coherence of the structural logic (structural usefulness).

Abstract: The basilica st. Jiri on Prague Castle has two towers and three bodies. The north tower is deflected from vertical about 450mm. During the last measurement it was found, that the walls were diverted too. The reasons and beginning of fault genesis have not been known yet. It can be larger self weight of tower then weight of navy. It leads to different settlements during homogenous foundation conditions. The next reasons are not clear. I investigated: tower weakening by the door opening, influence of inside vault over middle navy, foundation conditions. The results obtained from numerical model show that every mentioned reason contributed to the deflection of the tower.

Abstract: The Broumov group of churches represents an integral part of Bohemian baroque architecture. The famous Dientzenhofer family of architects, that helped define the Bohemian baroque style in the early 18th century, designed the Broumov group for the governing Benedictine abbey of St. Wenceslaw in Broumov. This report summarizes a structural investigation, using FIN10 finite element software, into the stability and efficiency of the roof trusses design. The structures age and current state were taken into account in calculating both the applied loads and structural capacity by increasing loads and reducing material strength. A damage analysis, including identification of fungi species, was performed, documented and implemented in a three-dimensional model for comparison with undamaged results. Magnitude and distribution of axial and bending forces were determined using both two dimensional and three-dimensional models for several load cases. Using the comparison of 1st order and 2nd order structural analysis results and Eurocode specified criteria, critical and unnecessary members of the roof system were identified and evaluated. Classical linear elastic 2nd order theory was used based of Eulerian principles, ignoring geometrical non-linearity and non-linear material effects. The main analysis was performed on the St. Ann church in Viznov and St. Barbora church in Otovice.

Abstract: The Prince of Wales Fort, in Churchill Manitoba, was constructed in the early 18th century by the Hudson Bay Trading Company (HBC) in an effort to secure the fur trade in northern Canada. The fort is a Vauban style rubble masonry construction, and is the most northerly fortification of this kind. In the 1920’s the fort received recognition as a National Historic Site by the Historic Sites and Monuments Board of Canada, at which time monitoring and repairs began under the leadership of Parks Canada. As a result of the fort’s northern latitude it has been subjected to extreme temperatures and freeze thaw cycles causing a gradual break down of the mortar within the escarp walls. Recently, climate change has led to an increase in the average local temperature shifting the thermal gradient within the earth rampart. During spring and summer, high volumes of ground water have drained through the walls washing out much of the degraded mortar. The result is a partially grouted rubble wall, encased with ashlar face stones. These deteriorating core conditions have caused significant lateral deflections in several areas and failure in others. The core wall material will be analyzed by modeling it as an irregular granular material. Using this approach, different levels of cohesion can be used to determine the in-situ mortar conditions and the strength of the structure.

Abstract: Based on the past monitoring data of crack movements and various weather conditions by JASA (Japanese Government Team of Safeguarding Angkor), we quantitatively examine about the effects of each weather conditions to each crack movements at Bayon main tower. Then, we applied the time series analysis using a state-space representation in the examination. In the model of the state-space representation, the factors of crack movement are assumed as temperature, wind velocity and rainfall. Those quantitative examinations of crack movements will be necessary for the planning of reinforcement and restoration at Bayon main tower.