Tower construction Eastern span replacement of the San Francisco–Oakland Bay Bridge

-


march 4, 2011: phase 4 4 columns in place; jack-up crane (to left) used erect , dismantle scaffold, , gantry crane atop scaffold lifts , places tower columns.


the process build sas tower atop foundation consisted of 5 phases. first 4 phases each consisted of lifting 4 similar columns , bolting them place , elements connecting them, while last phase lift final top cap carry crowning main cable saddle. on july 28, 2010, first of 4 below-deck main tower pillars erected, having arrived earlier in month barge china. placed lifting 1 end barge temporary scaffold, carriage on barge allow lower end move place. after columns bolted place, scaffolding extended upward allow next set of above deck columns erected, lifted, , translated position, process repeated each of remaining phases.


tower erection continued when second set of columns arrived in week of october 24, 2010, 3 months after first set placed. second set of columns erected gantry atop scaffold , placed on first 4 columns placed earlier in year. after columns set place, bolted first set of columns. after second phase complete, tower 51 percent completed , stood @ height of 272 feet. third set of tower columns did not arrive until week of december 15, 2010. third set, larger crane, lifted , placed on second set of columns. tower stood @ impressive height of 374 feet , 71 percent complete. erection process did not continue until following year when final set of tower columns arrived valentine s day 2011. these 4 columns, each being 105.6 feet tall, lifted in week of february 28, 2011 , placed on third set of columns. tower stood @ height of 480 feet , 91 percent complete.



april 15, 2011: grillage in place.


the fifth , final tower phase lift grillage (a structure join columns, more commonly used foundation element) weighs 500 tons, lift main 450-ton cable saddle, , lift final tower head completed entire sas tower. of these final pieces arrived @ site same day fourth set of tower columns arrived. on april 15, 2011, first part of fifth , final phase began. 500-ton grillage lifted 500 feet in air , placed on fourth set of columns. tower stood @ height of 495 feet , 94 percent complete. took 1 day lift , place grillage on top of tower.








Comments

Post a Comment

Popular posts from this blog

Early forms Nasal helmet

-
helmet of saint wenceslaus, prague the nasal helmet characterised possession of nose-guard, or nasal , composed of single strip of metal extended down skull or browband on nose provide facial protection. helmet appeared throughout western europe late in 9th century, , became predominant form of head protection, replacing previous types of helmet design based on late roman types such ridge helmet , helmets of spangenhelm construction. nasal helmets universally conical in shape. skull raised single sheet of iron or of composite, segmented (spangenhelm) construction. spangenhelm variety was, in general, earlier method of construction. single-piece skulls, being technically more difficult produce, became more common increase in metallurgical skill on time. though nasals had been used on earlier helmets, , on contemporary helmets found in byzantium, slavic eastern europe , middle east, characteristic of nasal helmet in general larger , integrated either skull or browband of helmet. nasal...
Read more

History Fixed exchange-rate system

-
1 history 1.1 chronology 1.2 gold standard 1.3 bretton woods system 1.4 current monetary regimes history the gold standard or gold exchange standard of fixed exchange rates prevailed 1870 1914, before many countries followed bimetallism. period between 2 world wars transitory, bretton woods system emerging new fixed exchange rate regime in aftermath of world war ii. formed intent rebuild war-ravaged nations after world war ii through series of currency stabilization programs , infrastructure loans. 1970s saw breakdown of system , replacement mixture of fluctuating , fixed exchange rates. chronology timeline of fixed exchange rate system: gold standard the earliest establishment of gold standard in united kingdom in 1821 followed australia in 1852 , canada in 1853. under system, external value of currencies denominated in terms of gold central banks ready buy , sell unlimited quantities of gold @ fixed price. each central bank maintained gold reserves official reserve asset. example, du...
Read more

Early years .281995.E2.80.931999.29 History of D.C. United

-
1 years (1995–1999) 1.1 d.c. awarded inaugural mls franchise 1.2 immediate success (1996–99) 1.2.1 1996: debut double 1.2.2 1997: back-to-back league titles 1.2.3 1998: international glory 1.2.4 1999: rongen steps in early years (1995–1999) d.c. awarded inaugural mls franchise prior 1994 fifa world cup, united states soccer federation fulfilled promises fifa aiding in foundation of new professional league. on june 15, 1994, major league soccer selected washington, d.c. out of twenty-two applicants host 1 of first 7 franchises, 3 more added before league s launch. once mls franchise awarded washington, new management had name it. in keeping sports naming conventions in united states, earliest efforts entailed area s name followed mascot. ideas included spies , americans , eagles . eventually, however, new team s operators decided name team d.c. united . name united alluded well-known european club names such leeds , manchester united, , reflected team s location in capital of uni...
Read more