An improved theoretical formulation is proposed here to predict the moment field induced in laterally loaded RC rectangular stiffened plates including the effect of strength and stiffness of the internal stiffening beams. Design charts are also presented for their quick proportioning. The study reveals the effect of strength and stiffness of the internal beams on the moment field induced in the plate-system which was not considered, currently, by various methods prescribed by different design codes. The use of stiffened-plates becomes mandatory in buildings to accomodate some architectural constraints as well as for satisfying the serviceability criterion of design codes. This type of a structural system is efficient, economical and readily constructible in most of common materials. Moreover, it can be built as a monolithic unit or as a composite system comprising a plate cast in concrete and beams constructed in prestressed concrete, fabricated sections in steel, and so forth. A working example is presented to demonstrate the validity and efficiency of the simplified approach in comparison to finite element based design and other code prescribed methods. and Obsahuje seznam literatury a Appendix A
The rock architecture that forms part of the folk architecture has up to now been only inadequately studied. The present study is based primarily on the field researches that have been realized ince the 1950s by the Ethnological Institute of the Czech Academy of Sciences (up to the year 1999, Institute for Ethnography and Folklore Studes of the Czech Academy of Sciences), researches that cannot be thought of without mentioning the name of Emanuel Baláš. The author of the present study himself realized the researches in the second half of the 1990s. The study aims to present, in historical perspective, the special type of primarily provisional dwellings that were being hollowed out primarily in the sandstone rocks. Beside the living quarters, the attention is dedicated also to other types–for example, to the out-buildings (such as barns, cellars) and technical buildings (water mills, blacksmith shops, drying-rooms) that are found in greatest number in the regions of Mělník, Mladá Boleslav, Děčín, Česká Lípa and Semily. According to the datation, the majority of the rock dwellings had been excavated since the second half of the eighteenth century and especially during the whole nineteenth century. But it is beyond doubt that such objects had existed also before, probably already in the Middle Ages, when they had especially the function of temporary refuges. The making of a rock dwelling was in the majority of the cases conditioned by the social status of the „builders“ that belonged among the poor classes. This was especially the case of the local agriculture workers (for example in the region of Mělník) and also of the seasonal workers from Slovakia that were coming especially after the founding of Czechoslovakia. There are many diferences in the disposition, extent and arrangement of the rock dwellings, even though from the point of view of typology this dwelling stems from the three-part chamber house. The incomplete character of the rock dwelling that often was reduced to a hall with a room was caused on the one hand by the economic situation o f the owners, but primarily by the natural conditions (the shape and size of the sandstone massive). The process of the rapid extinguishment of the rock dwellings started after the year 1945 when many of their inhabitants moved out during the settlement of the frontier regions. Minor part of the objects has up to now been used as barns or cellars.