【正文】 ijan,located on the western side of the Centennial Bridge –named to memorate 100 years of Panamanian independencehas noe been constructed and, when opend, will carry six lanes of traffic. This cablestayed bridge of castinplace cancrete features a main span of 420m,the longest such span for this type of bridge in the Western Hemisphere. In 200 the MOP invited international bridge design firms to pete for the design of the crossing, requesting a twopackage proposal:one techinical, the other financial. A total of eight proposals were received by December 2020 from established bridge design firms all over the world. After shortlisting three firms on the basis of the technical merits of their proposals, the MOP selected International, of San Francisco, to prepare the bridge design and provide field construction support based on the firm’s financial package. The Centennial Bridge desige process was unique and aggressive,incorporating concepts from the traditional design/build/bid method, the design/build method , and the sacalled fasttrack design plete the construction on timethat is ,within just 27 monthsthe design of the bridge was carried out to a level of 30 percent before construction bidding began, in December selected contractorthe Wiesbaden,Germany,office of Bilfinger Berger,AGwas brought on board immediately after being selected by the MOP ,just as would be the case in a fasttrack approach. The desige of the bridge was then pleted in conjunction with construction , a process that id similan to desige/build. The design selected by the client features two singlemast towers,each supporting two sets of stay cables that align in one vertical was used to construct both the towers and the box girder deck,as well as the approach structures. The MOP , in conjunction with the Panama Canal Authority,established the following requirements for the bridge design : A 420m,the minimum length for the main span to acmodate the recently widened Gaillard Cut,a narrow portion of the canal crossing the Continental Divide that was straightened and widened to 275m in 2020。 A deck able to acmodate a wide pedestrian walkway。 the probability that it will be exceeded within 50 years is 10 pencent and within 100 years,18 SEE is assumed to have a peak acceleration of and a return period of 2,500 years。Structrures,Inc.(CSI), of Berkeley, program was selected for its ability to easily model the service loads and to account for tridimensional correct SAP2020 modeling, it was necessary to define a set of initial stresses on the cables, deck, and tower elements to capture the state of the structure at the end of the calculation of those initial stresses, a series of iterations on the basic model were performed to obtain the stay forces in the structure that balance both the bridges’s selfweight and the superimposed dead loads. Once the correct cable stiffness and stress distribution were obtained, all subsequent serviceload analyses were performed to account for the geometric stiffness and Pdeltaeffects, which consider the magnitude of an applied load (P) versus the displacement(delta). The seismic analysis of the structure was conducted using the SADSAP structural analysis program, also a CSI product, based on the differences in seismic motions that will be experienced at the different piers based on their distance from one sophisticated program has the capability to model inelastic behavior in that flexural plastic hinges can readily be hinge elements were modeled at varous locations along the structure where the results from a preliminary response spectrum analysis in SAP2020 indicated that inelastic behavior might be timehistory records pertaining to the site were used in conjunction with the SADSAP model to botain a performacebased design of the piers and towers and to verifh the design of several deck stctions. As previously mentioned,the construction contractor was brought on board early in the process。用于聯(lián)系位于運河東部的巴拿馬城北部地區(qū)和運河西部。 2020 年 12 月， MOP 總共收到了來自全球各地橋梁設計公司的 8個方案。選擇的承包商 — 法國的 Wiesbanden在被 MOP 相中后立即簽訂 了合同。 MOP 聯(lián)同巴拿馬運河當局就大橋的設計提出了如下要求： ● 主跨長度不得小于 420m，能適應最近加寬的 Gaillard Cut— 運河的一小部分，橫跨 Continental Divide， 2020 年被修補過并加寬到了 275m。每個方向 3 車道。 ● 施工方法不能妨礙運河的正常工作，不管何時、用什么方法。 纜索的塔柱結構必須建在避免偶然的輪船沖擊力，還需要在水中修建深基礎，這兩方面是最重要的。然而運河西面地質是臭名昭著的 Cucaracha 結構，也就是頁巖粘土混雜砂巖、玄武巖和灰，很容易造成崩塌、滑坡。工程的地震荷載設計是基于考慮到該位置的可能地震危險估計（ PSHA）。 的Rio Gatun Fault 震級被作為地震時的，一個微小的地震運動只對橋造成及小的損害不會產(chǎn)生裂紋。為了研究分析橋梁雙重支撐的耐久性（縱向、橫向、豎向）組成的綜合運動，需要借助反復工藝過程。這些研 究通過土壤不同深度的淺性堆積和非淺性堆積研究來實現(xiàn)。 一旦以上的分析完成， 國際公司的工程師考慮到該工程負責人的要求對幾個不同的混凝土斜拉索設計進行評估對此。工程負責人后選擇了單桿塔，因為這樣設計施工簡便，可運作、簡單又不失優(yōu)雅。這些標準化的伸縮縫允許橋面板有 400mm 的伸縮風 4。支座和塔柱處的橋面板允許在縱向活動。特別是東西塔柱、連接結構和墩臺需要深扎于 Cucaracha 結構中。縱向鋼筋的布置應滿足以下規(guī)范要求，考慮承包商優(yōu)先選擇的 CIDH 柱施工的限制。橫向鋼筋呈螺旋布置。在縱橋向上，從塔底部的 到拱上建筑標高處恰好寬度為 8m，且矢高為 87m。 索塔被設計的應用了先進的 ATC 抗震技術。的鉤子鉤住。這些交叉的地方?jīng)]有豎向預應力鋼筋， 并且設置在距塔的中性軸較近的地方，橋面構造也要設置預應力。這種方法需要一種模型，此模型的構造件的性能反應墩的性能。 橋面建筑的用懸索拉起的主跨是由整體澆注的單獨的箱梁組 成的，包括鋼筋，肋板、梁、并向塔高的方向。與整體澆注相比，它是沿架設的箱梁澆注的，碾壓設備被應用來獲得平整度的路面。對鋼鉸線的保護包括對于進行扭處理，及張拉，和一種特殊的材用充滿數(shù)根鋼鉸線之間。鋼架被設計成通過縱向橋的橋面轉移水平力，并且通過整體的鋼結構轉移豎向力。這個程序被成功的應用到 40 座懸索橋的分析設 計中， TANGO 使得在不同的建筑狀態(tài)下模擬不同的結構分析成為可能。通過這些初始應力的計算，基于基礎模型的一連串迭代法可以得到結構中用于平衡橋梁自重和超靜載。彼此之間距離不同的不同橋墩之間，地震運動也是不同的。 在前面提到過，工程 承包商在施工過程的早期就動工了，該公司的 9300 萬美元的投標競標成功， 2020 年 3 月交付工程。完成基座部分的組裝之后，兩獨立地立在就地澆注的橋墩基座上，被此相互連接。東面高架橋主跨先被修建起來，然后移去支撐絎架遷至 西面，這樣可以同時修西面高架橋的三根橋跨和一根