Prestressed membrane roofs have been designed since the invention of prestressed concrete. They are described in the basic books written by pioneers of prestressed concrete. For illustration, four architecturally most successful roofs are discussed. The authors emphasize that the prestressed membrane roofs are still modern, structurally efficient, and architecturally interesting. If they are assembled of precast members, they can be erected without scaffolding. Recently, the authors have studied different membrane structures from the point of view of their architectural and structural arrangement, process of erection, and static and dynamic behavior. In‐depth studies were carried out for membranes of simple curvature situated above the whole or portion of the rectangle area and self‐anchored membranes supported by arches or shells. Also self‐anchored suspension membranes situated above circular or elliptical plans, hypar membranes, and membranes of a free form that are suspended on arches or suspension cables were analyzed.

The effect is studied of the activated carbon moisture on the recovery (R) of some organic substances, viz. benzene, acetone, tetrahydrofuran, ethanol, 2-methyl-1-propanol, and 1-butanol, trapped from air of different humidity and desorbed with carbon disulphide to equilibrium. If the weight fraction of water in the activated carbon is w = 0.02, the variations of R lie within the limits of error (for 0.3 g of activated carbon and 5 ml of CS2), whereas if w = 0.15, the variations of R, if disregarded, can result in errors as high as -45% for ethanol and -6 to -12% for butanol and acetone. In the case of benzene and tetrahydrofuran, the increase in the water content in the carbon does not affect the R value. The error increases as the activated carbon-to-carbon disulphide weight ratio is raised. For the standard addition method, the relative error was in average 18% (largely negative) for ethanol and -4.5 to -13% for the remaining substances.

<p>Four arch pedestrian and cyclist bridges built in the USA, Slovakia and in the Czech Republic are described in terms of their architectural and structural solution, static and dynamic behaviour, and technology of their construction. The bridges with span length up to 104 m have slender decks which are suspended on arches of a butterfly arrangement. The dynamic analysis proved that all structures are comfortable to users. The footbridges are structurally efficient, they are light and transparent, correspond to the scale of the landscape and all structural members have human dimensions.</p>

<p>Three suspension pedestrian and cyclist bridges built in Sweden and in the Czech Republic are described in terms of their architectural and structural solution, static and dynamic behaviour, and technology of their construction. The bridges with span length up to 179 m have slender decks which are fix connected with suspension cables. The dynamic analysis proved that all structures are comfortable to users and they have a sufficient aerodynamic stability. The footbridges are structurally efficient, they are light and transparent, correspond to the scale of the landscape and the structural members have human dimensions.</p>