贯通六级词汇的文章（21） [00:00.00]UNIT12 [00:13.55]The American Dream [00:15.84]The dream to construct a building [00:19.89]to house everyone and everything [00:21.97]connected with world trade [00:23.94]began in the early 1960's. [00:27.34]After much deliberation， [00:29.41]Minoru Yamasaki was commissioned [00:33.13]over more than a dozen other architects [00:35.98]to work with the firm of Emery Roth [00:39.04]and Sons to design this massive edifice. [00:42.11]His task was evident: [00:45.05]the building must have [00:46.92]twelve million square feet of floor space [00:49.98]on a sixteen acre parcel of land, [00:52.93]accommodate the new facilities [00:55.12]for the Hudson tubes and subway connections, [00:57.97]and be done within the 500 million dollar budget. [01:02.12]The relatively small site [01:04.86]combined with the vast space [01:07.05]needs meant that [01:08.36]the only way to go was up. [01:10.44]The development would dwarf its neighbors [01:14.16]and change the New York landscape [01:16.13]and skyline at the bottom of Manhattan. [01:19.52]In order to accommodate [01:23.13]the nine million square feet of office space, [01:26.09]Yamasaki made the decision [01:28.16]that a two?tower development would be best. [01:31.33]This would serve the dual purpose [01:34.18]of giving sufficient office area [01:36.81]on each floor and allowing a manageable structural system [01:40.74]while taking advantage of the superb views. [01:43.92]The twin towers would be 110 floors each, [01:48.73]rising to a height of 1,353 feet (412 meters). [01:56.06]From the observation decks [01:59.23]at the tops of the towers [02:00.76]it would be possible to see 45 miles [02:03.94]in every direction. [02:05.69]When asked why he designed two 110-storey buildings [02:11.49]instead of one 220-storey building, [02:15.21]he replied, flippantly, “ [02:17.28]I didn?t want to lose the human touch.” [02:20.35]The first act in the construction process [02:25.05]was the excavation. [02:26.48]The 1.2 million cubic yards of earth [02:30.63]and rock that were removed [02:32.49]were used to create 23 acres of fill [02:35.55]in the Hudson River adjacent to the W.T.C. site. [02:40.37]This landfill project was subsequently developed [02:45.29]as Battery Park. The excavation, [02:48.79]besides providing the foundation [02:50.98]for this enormous construction, [02:52.95]would house parking garages, [02:55.14]subway terminals and tubes, [02:57.54]and shopping concourses. [02:59.08]Yamasaki believed that [03:02.91]all buildings must be strong [03:04.66]in the context of being dominant. [03:07.17]He felt that each building should [03:10.24]“be a monument to the virility of our society”. [03:14.07]The structural system, [03:17.24]while possessing this strength, [03:19.31]is also impressively simple. [03:21.94]The 208-foot front wall [03:25.34]is essentially a pre-assembled steel web, [03:28.61]with columns on 39?inch centers, [03:31.68]providing the wind bracing necessary [03:34.41]for a building of this height, [03:35.94]allowing the central core [03:38.35]to take only the gravity loads. [03:40.65]This very light, [03:42.84]economical configuration would result in [03:46.01]keeping the wind bracing [03:47.54]in the most efficient place, [03:49.18]the outside shell of the building. [03:51.70]In this way, the wind force [03:54.87]would not be transferred [03:56.62]through the floor membrane to the core. [03:58.92]Thirty?three inch deep floors [04:02.31]made of prefabricated steel trusses [04:05.49]would act as supports to stiffen the outside walls [04:09.09]against the buckling forces [04:10.95]of the wind?load pressures. [04:13.36]There would be no interior columns [04:16.76]in the office spaces, [04:18.29]an amazing feat [04:19.92]as there would be 40 000 square feet [04:23.21]of office space on each of the upper floors. [04:26.17]In total, there would be seven buildings [04:30.87]in the complex; [04:36.34]the twin towers standing 110 stories high , [04:36.08]four smaller towers, [04:38.27]and a central plaza. [04:39.70]Also, there would be seven underground levels [04:44.18]containing services, [04:45.38]shopping, parking garages and a subway station. [04:49.43]When completed, there would be [04:52.38]ten million square feet of leasable space, [04:55.88]or an acre of rentable space [04:58.51]on each floor of each tower. [05:00.70]The elevator system was intended to be fast, [05:05.26]efficient,and space saving. [05:07.67]Express elevators opening onto the forty-first [05:11.61]and seventy-fourth floors [05:14.24]would serve the sky lobbies. [05:16.31]From these floors and from the plaza, [05:19.70]four banks of elevators would [05:22.22]carry passengers to each of the three zones. [05:25.06]Tenders posted, contractors hired, [05:29.23]and the preliminary materials purchased, [05:31.85]the groundbreaking ceremony [05:33.82]was held on August 5, 1966. [05:38.85]Some offices were ready for occupancy [05:42.24]in 1970 but the ribbon cutting ceremony |
