The design and construction of tall and slender steel structures is always challenging. This paper discusses several design aspects (structural information, analysis methods, applied loads, cost optimisation) and a ca...The design and construction of tall and slender steel structures is always challenging. This paper discusses several design aspects (structural information, analysis methods, applied loads, cost optimisation) and a case study regarding the design and construction of 10-m-tall windbreak panels for a Greek electricity producer. The purpose of the panels is to reduce wind turbulence and improve the performance of the electricity producer’s air-cooled condenser. In this case, the main wind load acts in the longitudinal direction, with friction inducing only a small amount of wind load in the transverse direction. The steel columns are constructed from 10-m-tall hot-rolled IPE 270 (S235) cross-sections, and are supported by cables in the longitudinal direction and bracing systems in the transverse direction. Concrete anchorages and concrete footings are used for the cables and steel columns, respectively. System optimisation is investigated in terms of the steel weight, cable length, and overall cost, and practical issues are explained regarding technical decisions. Furthermore, the construction details, construction methods, and cost estimation are discussed.展开更多
The main objective of the present study is the assessment and retrofit of an existing road bridge that is located in Cyprus over the river Kouris. In particular the study concerns in a road bridge with seven spans of ...The main objective of the present study is the assessment and retrofit of an existing road bridge that is located in Cyprus over the river Kouris. In particular the study concerns in a road bridge with seven spans of 10.5 m + 5 * 12.6 m + 10.5 m, a cross section width of 7.10 m and a 5 m piers height that was constructed in the early 50’s. The structural system of the bridge comprises of cast in situ reinforced concrete T-beams and slab deck that is simply supported on masonry piers. According to the new urban plan to design the bridge should now accommodate two lanes per direction, a pedestrian walkway and a cycling lane with total cross section width of new deck 15.60 m. The deck of the bridge widened using for aesthetic reasons the same cross section type and the new T-Beams and slab deck connected monolithically to the existing one. The existing part of the deck was strengthened with reinforced concrete jacketing due to inadequacy in shear resistance. Major challenge of the project posed the existing masonry pier layout that was insufficient to carry the new design seismic forces. New piers, founded on piles, were designed adjacent to the existing piers in order to support the new widened part of the bridge, and also to bear all the horizontal loads arising from the masses of the total deck. Sliding bearings (free movement) placed in the part of the bridge over the existing piers and elastomeric bearings with movement only in the longitudinal direction placed in the new piers.展开更多
文摘The design and construction of tall and slender steel structures is always challenging. This paper discusses several design aspects (structural information, analysis methods, applied loads, cost optimisation) and a case study regarding the design and construction of 10-m-tall windbreak panels for a Greek electricity producer. The purpose of the panels is to reduce wind turbulence and improve the performance of the electricity producer’s air-cooled condenser. In this case, the main wind load acts in the longitudinal direction, with friction inducing only a small amount of wind load in the transverse direction. The steel columns are constructed from 10-m-tall hot-rolled IPE 270 (S235) cross-sections, and are supported by cables in the longitudinal direction and bracing systems in the transverse direction. Concrete anchorages and concrete footings are used for the cables and steel columns, respectively. System optimisation is investigated in terms of the steel weight, cable length, and overall cost, and practical issues are explained regarding technical decisions. Furthermore, the construction details, construction methods, and cost estimation are discussed.
文摘The main objective of the present study is the assessment and retrofit of an existing road bridge that is located in Cyprus over the river Kouris. In particular the study concerns in a road bridge with seven spans of 10.5 m + 5 * 12.6 m + 10.5 m, a cross section width of 7.10 m and a 5 m piers height that was constructed in the early 50’s. The structural system of the bridge comprises of cast in situ reinforced concrete T-beams and slab deck that is simply supported on masonry piers. According to the new urban plan to design the bridge should now accommodate two lanes per direction, a pedestrian walkway and a cycling lane with total cross section width of new deck 15.60 m. The deck of the bridge widened using for aesthetic reasons the same cross section type and the new T-Beams and slab deck connected monolithically to the existing one. The existing part of the deck was strengthened with reinforced concrete jacketing due to inadequacy in shear resistance. Major challenge of the project posed the existing masonry pier layout that was insufficient to carry the new design seismic forces. New piers, founded on piles, were designed adjacent to the existing piers in order to support the new widened part of the bridge, and also to bear all the horizontal loads arising from the masses of the total deck. Sliding bearings (free movement) placed in the part of the bridge over the existing piers and elastomeric bearings with movement only in the longitudinal direction placed in the new piers.
