Starting with the Ertan arch dam （240 m high, 3300 MW） in 2000, China successfully built a total of seven ultra-high arch dams over 200 m tall by the end of 2014. Among these, the ]inping 1 （305 m）, Xiaowan （294...Starting with the Ertan arch dam （240 m high, 3300 MW） in 2000, China successfully built a total of seven ultra-high arch dams over 200 m tall by the end of 2014. Among these, the ]inping 1 （305 m）, Xiaowan （294.5m）, and Xiluodu （285.5 m） arch dams have reached the 300 m height level （i.e., near or over 300 m）, making them the tallest arch dams in the world. The design and construction of these 300 m ultra-high arch dams posed significant challenges, due to high water pressures, high seismic de- sign criteria, and complex geological conditions. The engineering team successfully tackled these chal- lenges and made critical breakthroughs, especially in the area of safety control. In this paper, the author summarizes various key technological aspects involved in the design and construction of 300 m ultra- high arch dams, including the strength and stability of foundation rock, excavation of the dam base and surface treatment, dam shape optimization, safety design guidelines, seismic analysis and design, treatment of a complex foundation, concrete temperature control, and crack prevention. The experience gained from these projects should be valuable for future practitioners.展开更多
A review of the current status and progress of steel arch bridges in China is presented in this paper. The existing steel arch bridges in China were analyzed in terms of steel material, span, structure type, main arch...A review of the current status and progress of steel arch bridges in China is presented in this paper. The existing steel arch bridges in China were analyzed in terms of steel material, span, structure type, main arch rib form and construction method. The comparison with CFST arch bridges and RC arch bridges is also conducted. It is shown that steel arch bridge has gain rapid development in China since 2000, characterized by long main spans. As for the span, most of the steel arch bridges have a span less than 250 m, while when the span exceeds 350 m, steel arch bridges are strongly competitive against CFST or RC arch bridges. Over 80% of the bridges are through and half-through bridge types, and the arch ribs are hingeless structures. The rise-to-span ratios of the arches are mainly between 1：4 and 1： 5. Most of the arches use solid box ribs, and a small portion of arches use truss ribs in which box sections are mostly adopted for the truss members. The cantilever method and scaffolding method are the two main construction methods used, but some other construction methods have also been developed.展开更多
Linear monitoring is an important link of bridge construction control,which is conducted in key processes of construction to ensure the security of bridge in construction procedure. Combining with main arch constructi...Linear monitoring is an important link of bridge construction control,which is conducted in key processes of construction to ensure the security of bridge in construction procedure. Combining with main arch construction monitoring program of No. 2 bridge in north district of Changbai international tourism resort,main content and key technologies are recommended. Considering the various influential factors during the construction process,linear adjustment is handled to ensure that the stress and linear of main arch meet design requirements.展开更多
The use of Network hanger arrangement, a development of the classical Nielsen V-hanger system, in steel bowstring arch bridges allows for important steel saving, with very slender main elements, owing to the remarkabl...The use of Network hanger arrangement, a development of the classical Nielsen V-hanger system, in steel bowstring arch bridges allows for important steel saving, with very slender main elements, owing to the remarkable reduction of bending stresses in the arches and tie beams. The present paper describes the main features of the design and construction of several long-span arch bridges of this typology in Spain： the three pedestrian footbridges for the Madrid cycling ring track, with spans of 52, 60 and 80 m, the Bridge over River Deba in Guipuzcoa with a span of 110 m and Palma del Rio Bridge over River Guadalquivir in Cordoba, 130 m long. In all cases, two inclined arches linked at the crown were implemented, a very effective disposition to reduce the out-of-plane buckling length. The multiple crossings of the hanger system, consisting of prestressed bars in the case of Deba Bridge and the footbridges, and locked coil cables for Palma del Rio Bridge, were dealt with by means of crossing devices which led to a technically satisfactory solution with minimal visual impact. An innovative approach to bowstring arches was introduced in Valdebebas Bridge over M-12 motorway in Madrid, next to the new T-4 Terminal of Barajas Airport, with a span of 162 m, where the hangers are replaced by a structural steel mesh -diagrid- which acts as the web of a simply-supported beam whose compression head is the arch and the tie beam is the deck.展开更多
文摘Starting with the Ertan arch dam （240 m high, 3300 MW） in 2000, China successfully built a total of seven ultra-high arch dams over 200 m tall by the end of 2014. Among these, the ]inping 1 （305 m）, Xiaowan （294.5m）, and Xiluodu （285.5 m） arch dams have reached the 300 m height level （i.e., near or over 300 m）, making them the tallest arch dams in the world. The design and construction of these 300 m ultra-high arch dams posed significant challenges, due to high water pressures, high seismic de- sign criteria, and complex geological conditions. The engineering team successfully tackled these chal- lenges and made critical breakthroughs, especially in the area of safety control. In this paper, the author summarizes various key technological aspects involved in the design and construction of 300 m ultra- high arch dams, including the strength and stability of foundation rock, excavation of the dam base and surface treatment, dam shape optimization, safety design guidelines, seismic analysis and design, treatment of a complex foundation, concrete temperature control, and crack prevention. The experience gained from these projects should be valuable for future practitioners.
文摘A review of the current status and progress of steel arch bridges in China is presented in this paper. The existing steel arch bridges in China were analyzed in terms of steel material, span, structure type, main arch rib form and construction method. The comparison with CFST arch bridges and RC arch bridges is also conducted. It is shown that steel arch bridge has gain rapid development in China since 2000, characterized by long main spans. As for the span, most of the steel arch bridges have a span less than 250 m, while when the span exceeds 350 m, steel arch bridges are strongly competitive against CFST or RC arch bridges. Over 80% of the bridges are through and half-through bridge types, and the arch ribs are hingeless structures. The rise-to-span ratios of the arches are mainly between 1：4 and 1： 5. Most of the arches use solid box ribs, and a small portion of arches use truss ribs in which box sections are mostly adopted for the truss members. The cantilever method and scaffolding method are the two main construction methods used, but some other construction methods have also been developed.
文摘Linear monitoring is an important link of bridge construction control,which is conducted in key processes of construction to ensure the security of bridge in construction procedure. Combining with main arch construction monitoring program of No. 2 bridge in north district of Changbai international tourism resort,main content and key technologies are recommended. Considering the various influential factors during the construction process,linear adjustment is handled to ensure that the stress and linear of main arch meet design requirements.
文摘The use of Network hanger arrangement, a development of the classical Nielsen V-hanger system, in steel bowstring arch bridges allows for important steel saving, with very slender main elements, owing to the remarkable reduction of bending stresses in the arches and tie beams. The present paper describes the main features of the design and construction of several long-span arch bridges of this typology in Spain： the three pedestrian footbridges for the Madrid cycling ring track, with spans of 52, 60 and 80 m, the Bridge over River Deba in Guipuzcoa with a span of 110 m and Palma del Rio Bridge over River Guadalquivir in Cordoba, 130 m long. In all cases, two inclined arches linked at the crown were implemented, a very effective disposition to reduce the out-of-plane buckling length. The multiple crossings of the hanger system, consisting of prestressed bars in the case of Deba Bridge and the footbridges, and locked coil cables for Palma del Rio Bridge, were dealt with by means of crossing devices which led to a technically satisfactory solution with minimal visual impact. An innovative approach to bowstring arches was introduced in Valdebebas Bridge over M-12 motorway in Madrid, next to the new T-4 Terminal of Barajas Airport, with a span of 162 m, where the hangers are replaced by a structural steel mesh -diagrid- which acts as the web of a simply-supported beam whose compression head is the arch and the tie beam is the deck.
