Jiří Bláha - Academia.edu (original) (raw)

Papers by Jiří Bláha

13th SGEM GeoConference on SCIENCE AND TECHNOLOGIES IN GEOLOGY, EXPLORATION AND MINING, Jun 20, 2013

A few years ago we acquired research project funding from the Ministry of Culture of the Czech Re... more A few years ago we acquired research project funding from the Ministry of Culture of the Czech Republic to develop a comprehensive methodology for the selection and craft processing of replacement stones for the repair of ashlar masonry in historical constructions. The main objective of the project called "Lapidarius" is to develop a model procedure for a comprehensive survey and the subsequent appropriate repairs of ashlar facing walls made of sedimentary rocks. In 2012 we participated in a battlement wall gallery restoration at the medieval Kost Castle solidly built of squared Cretaceous sandstones in the 14th century. First a detailed survey of its initial state was completed and then the stone masonry was described from a geological, structural and historical perspective. Depending on the kind and degree of damage and weathering, the stone elements that could be restored and those that needed to be replaced were determined. To replace the blocks it was necessary to find a matching local alternative rock or a comparable one from another site. Therefore a geological survey was made to identify and document possible historic quarries from where the stone for construction and subsequent repairs of the castle walls was taken. During the repair copies of historical stonemasonry tools were used as well as stone working technologies from the periodboth with an utmost respect towards authentic material.

New findings about the round tower of the castle formarly considered to be a part of the C13-C14 ... more New findings about the round tower of the castle formarly considered to be a part of the C13-C14 building period. The detailed research involving dendrodating proved that the tower was built in late medieval period after the fire in 1522. Under the spire roof made of bricks the timber scaffolding structure originally supporting the sheeting boards is preserved

The overview of the most significant European activities of the scientific research of historic t... more The overview of the most significant European activities of the scientific research of historic timber roofs from the half of the 19th century until now

Research and evaluation of timber structures used within historic buildings should have considera... more Research and evaluation of timber structures used within historic buildings should have consideration for an authentic substance bearing the most of specific heritage values. Modern technologies have brought new tools for a detection of the subsurface biogradation. Among the non-invasive techniques the ultrasonic testing, portable X-ray scanning and thermo-vision belong to most promising ones. There are also sophisticated semidestructive methods like microdrilling or video scope available

The present state of knowledge and documentation of historical roof trusses in Czech towns. An ov... more The present state of knowledge and documentation of historical roof trusses in Czech towns. An overview of the educational and leisure orientated activities of the last decades. Creating the concept of enhancing the historical towns as tourist attractions with the addition of tours accessing historical timber roofs and other significant artefacts of structural history situated in related attic spaces. It is a by-product of long-term research activities focused on building heritage identification and preservation, manifestations of regional cultural diversity and the transfer of historical technological innovations in Europe. Improvement of awareness for both professionals and the general public of traditional building carpentry, construction development and their manifestation in the urban environment. The first experiences of the realization of the tour route “Under the Roofs of the Cheb Houses” which was established in 2017

The vast majority of historic roofs in the region belong to the common rafter and collar typologi... more The vast majority of historic roofs in the region belong to the common rafter and collar typological group. The large diversity and variability of technical solutions, especially noticeable in the lengthwise frame construction allows us to trace the evolution of traditional carpentry as well as to map its local differences. The Bohemian-Moravian Uplands region is one of the relatively homogenous areas, where the timber transport distance from the place of felling the trees to the site was very short. There are no large rivers, and the altitude is 500-840 meters (about 1500-2500 ft.)above sea level

The multidisciplinary criteria for selecting, preparation and processing of a replacement stone f... more The multidisciplinary criteria for selecting, preparation and processing of a replacement stone for ashlar masonry were implemented in restoration and conservation of the Castle of Kost battlements – one of the most authentically survived medieval fortification monuments in the Czech Republic. Detailed description of undertaken surveys, preparation and interventions carried out within the repair process

The aim of this paper is to present the Report of innovative restoration techniques, technologies... more The aim of this paper is to present the Report of innovative restoration techniques, technologies and materials used in conservation in the context of natural sciences and heritage science of the RUINS Project. First, the specifics of preservation and maintenance of ruins are briefly described. Subsequently, the context of natural sciences and the new scientific discipline of heritage science, including the link to innovation, are indicated. The paper then presents the structure of the report and an example of one record representing one specific technique. Record structure is ready to be transferred to versatile data set so it could be converted into an updatable online database in the future.Celem artykułu jest przedstawienie raportu o innowacyjnych technikach restauratorskich, technologiach i materiałach stosowanych w konserwacji w kontekście nauk przyrodniczych i dziedzictwa przyrodniczego Projektu RUINS. W pierwszej kolejności opisano specyfikę ochrony i konserwacji ruin. Nastę...

Geologists, structural engineers, construction historians, conservationists and restorers formula... more Geologists, structural engineers, construction historians, conservationists and restorers formulated their views on the relevant intensity of interventions, the replacement stone quality and also the parameters of processing by craftsmen. Methodical guidelines define the necessary level of adequate historical, technological and structural surveys and, subsequently, propose an optimal procedure for laboratory tests and for the following repair processes of a particular structure

The designs of the low-cost roof trusses created at the end of 1820s by Prague carpenter of Hunga... more The designs of the low-cost roof trusses created at the end of 1820s by Prague carpenter of Hungarian origin Michael Ranek (1770-1842) form a sort of link between traditional trusses with collars and modern purlin constructions. The swift adoption of Ranek’s truss among carpenters was helped by the relationship of trusses to traditional collar systems, easier handling of beams with smaller profiles and last but, not least, its simplicity during fabrication and erection. During the course of the second half of the 19th century Ranek’s trusses, together with traditional trusses with collar beams, were forced out by new, progressive constructions, especially by the generally widespread purlin trusses

Photographic, x-ray and drawn documentation of the oak wood door frame dendrochronologicaly dated... more Photographic, x-ray and drawn documentation of the oak wood door frame dendrochronologicaly dated by means of non-destructive tree ring measuring to the years 1480-9

Grafická úprava a sazba © Břetislav Vašek K realizaci výstavy a katalogu svou obětavostí velkým d... more Grafická úprava a sazba © Břetislav Vašek K realizaci výstavy a katalogu svou obětavostí velkým dílem přispěli také kolegové, přátelé a rodinní příslušníci. Reprodukce na frontispisu: Detail dubového trámu ze štítové stěny

This contribution presents a project, which is solved in cooperation of Faculty of Civil Engineer... more This contribution presents a project, which is solved in cooperation of Faculty of Civil Engineering CTU, ITAM and NTM within the Program of applied research and development of national and cultural identity (NAKI) in the years 2012-2015. It’s practical parts deal with a broad knowledge of architectural history, historic craft technology and conservation’s practices. The main goal of the project is a development of comprehensive methodology for specialized surveys and processing of stone intended for replacements and repairs of the ashlar masonry of historic buildings mainly composed of sedimentary rocks. The output of the project will also help to determine a relevant intensity of interventions and also the parameters of craftsman’s processing, with an emphasis on respect for authenticity and specific characteristics of a particular historical monument. Use of this methodology will enable to obtain all adequate historical, technological, technical and structural surveys, and subseq...

WIT Transactions on The Built Environment, 2013

There are various macroscopic traces recognizable and readable on the surfaces of historical stru... more There are various macroscopic traces recognizable and readable on the surfaces of historical structures and materials. According to their origin they can be divided into several groups including traces of the transportation or other manipulation during construction; geometric schedules, height and direction lines, auxiliary design sketches; signs of wear and natural aging of materials; structural failures and impact of natural disasters; traces of subsequent additional modifications or conservation interventions; small epigraphical relics such as inscriptions, datings, the names of artisans or craftsmen, various graffiti etc. The traces of working tools are among the most important ones. They allow us to reconstruct forgotten arts and techniques performed by craftsmen or artisans in the past. For tool marks examination, the original surfaces intact with no later modifications or even conservation activities are very important. The sites with authentically preserved surfaces or details should therefore be registered, documented and then rigorously protected from adverse environmental factors and, if possible, in future spared any interventions including even attempts at conservation and restoration.

Journal of Ethnology, 2014

ABSTRACT The paper presents a project aiming to develop a knowledge-based system for documentatio... more ABSTRACT The paper presents a project aiming to develop a knowledge-based system for documentation and analysis of defects of cultural heritage objects and monuments. The MONDIS information system concentrates knowledge on damage of immovable structures due to various causes, and preventive/remedial actions performed to protect/repair them, where possible. The currently built system is to provide for understanding of causal relationships between a defect, materials, external load, and environment of built object. Foundation for the knowledge-based system will be the systemized and formalized knowledge on defects and their mitigation acquired in the process of analysis of a representative set of cases documented in the past. On the basis of design comparability, used technologies, materials and the nature of the external forces and surroundings, the developed software system has the capacity to indicate the most likely risks of new defect occurrence or the extension of the existing ones. The system will also allow for a comparison of the actual failure with similar cases documented and will propose a suitable technical intervention plan. The system will provide conservationists, administrators and owners of historical objects with a toolkit for defect documentation for their objects. Also, advanced artificial intelligence methods will offer accumulated knowledge to users and will also enable them to get oriented in relevant techniques of preventive interventions and reconstructions based on similarity with their case.

13th SGEM GeoConference on SCIENCE AND TECHNOLOGIES IN GEOLOGY, EXPLORATION AND MINING, Jun 20, 2013

WIT Transactions on The Built Environment, 2013

Journal of Ethnology, 2014