Specific Features of Historical Structures of Buildings and Road Facilities in Bulgaria in 19th and In the Beginning of 20th Century

The aim of the study is an analysis of some constructive systems in Bulgarian architecture in 19th century and in the beginning of 20th century. In the historical development of Bulgaria this is the time of changes in all areas of life. The period is connected with the transition from the Middle Ages to the Modern Era and the perception of the changes brought about by the industrial development in Europe. The wooden and steel constructions used in cult and public buildings and facilities have been explored. The use of different types of materials for these structures is related to the functions of the facilities, their social and industrial significance. In the course of the study, the hypothesis of the unity of the construction system and its relation to the terrain is confirmed. The unity of the construction system is considered as a significant problem, because builders during this period follow the local historical tradition and good knowledge of the craft. Following the tradition they work with historic, traditional materials such as wood and stone. The change with the constructions and the materials comes with the liberation of the Bulgaria in 1878. At that time an accelerated development of industrial production began. The active construction of buildings and road facilities is connected with steel structures of prefabricated elements. Often, they also come into use due to the compromised peculiarities of the terrain. In the study in chronological order were analyzed cult buildings with brick massive constructions, with wooden constructions and industrial steel structures. A cult building rare for the Bulgarian architecture, such as the church in Istanbul, is accented. It is assembled from pre-fabricated steel profiles in order to be reversible, portable and easily replaceable structural elements