【正文】 different geologicaland soil conditions. On the east side of the canal, beneath shallow layers of overburden that rangs in consistency from soft to hard, lies a block of basalt ranging from medium hard to hard with very closely spaced engineers determined that the basalt would provide a petent platform for the construction of shallow foundation for tower, piers, and approach structures on this side of west side, however,featured the infamous Cucaracha Formation, which is a heterogeneous conglomerate of clay shale with inclusions of sandstone, basalt,and ash that is prone to landslide. As a sudsurface stratum the Cucaracha Formation is quite stable,but it quickly erodes when exposed to the elements. The engineers determined that deep foundations would therefore be needed for the western approach structure,the west tower,and the western piers. Before a detailed design of the foundationa could be developed,a thorough analysis of the seismic hazards at the site was required,The design seismic load for the project was developed on the basis of a probabilistic seismic hazard assessment that considered the conditions at the an assessment establishes the return period for a given earthquake and the corresponding intensity of ground shaking in the horizontal directtion in terms of an acceleration response PSHA determined two dominant seismic sources: a subduction source zone associated with the North Panama Deformed Belt capable of producing a seimic event as strong as ,and the Rio Gatun Fault, capable of producing an event as strong as . The NPDB event was used as the safety evluation earthquake,that is,the maximum earthquake that could strike without putting the bridge out of damage to the bridge would be minor but would require some closures of the Gatun Fault event was used as the foundational evaluation earthquake,a lowerlevel temblor that would cause minimal damage to the bridge and would not require the FEE load case,the SEE loading was scaled back by FEE is assumed to have a peak acceleration of and a return period of 500 years。為了減輕大橋線路的平靜問題，促進巴拿馬西部地區(qū)的發(fā)展，國家公共工作部決定修建一個新的高速公路系統(tǒng)。為了能在 27 個月內(nèi)及時完成工程，在 2020 年 12 月施工開始前的設(shè)計工作的 30%得進展順利才行。 ● 車行道要足夠?qū)?，能容納 6 個車道。下列設(shè)計標準被 用來作為此橋的設(shè)計標準。 在制度基礎(chǔ)的詳細設(shè)計方案之前，需要對該位置的地震危險性作一個全面的分析。 由于接近該位置的地震波來說方向確定性，所以用單個反應(yīng)范圍（一條曲線顯示一批簡易 、潮濕、協(xié)調(diào)震動器的不同固有頻率與個別地震加速度的統(tǒng)計規(guī)律）來描述水平面上兩個相互垂直的運動的特征。因為橋所在位置包含許多不同土壤類型的土層，因此每一層需要用不同的硬度模量來表示然后進行分析。 橋的主梁從橋臺是一個連續(xù)的箱形絎架，并且只在支座處設(shè)置伸縮縫。 如前面提到過的東西地區(qū)玄武的存在意味著此處需要淺層基礎(chǔ)。橫向鋼筋的布置遵循以下規(guī)范，并考慮 CIDH 柱施工的局限。這種設(shè)計上的挑戰(zhàn)需要細節(jié)上的小心謹慎。因為在塔中間設(shè)置的懸索，它會提供足夠的抗扭鋼度和特殊的墩和橋面的連接是很有必要的。在這些地方提供鋼筋砼是有必要的，這些地方與基礎(chǔ)表現(xiàn)出所希望的形式。所有大于 80m 長度的索用器具設(shè)在塔頂?shù)哪┒?。為了估計人行道和這種長期效應(yīng)作用下的鋼筋松弛，一種被稱為 TANGO 的計算機程序被應(yīng)用，它由這篇文章的作者發(fā)展的，現(xiàn)在已被提供。 結(jié)構(gòu)的地震分析應(yīng)用一個名叫 SADSAP 的結(jié)構(gòu)分析程序，也是 CSI 的產(chǎn)品。用來完成，它們被設(shè)計成為橋墩基礎(chǔ)的腳手架的完整部分。 。在橋墩基座施工完成后，脫離開來進入最初澆鑄的橋面板位置。這個先進的程序能模擬可彎曲的塑性鉸 接處的非彈性行為。 為了工作荷載的分析，包括活載、溫度荷載和風荷載，工程師應(yīng)用了加利福尼亞的 Berkeley 公司發(fā)明設(shè)計的一個計算機程序，叫 SAP2020。 每隔 6m 設(shè)置懸索并且是成對設(shè)置的。每個箱梁件是 高， 6m 長。 主跨兩邊的結(jié)構(gòu)是支撐在一個 5m 的中空的預應(yīng)力砼的橋墩上。在沿縱向橋的方向上，特殊的細部結(jié)構(gòu)和區(qū)域被設(shè)計為塑料的，特別是橋面建筑下部和拱圈上部。 然而它們被設(shè)計成不同的作用，索塔被設(shè)計成完全相同的。這就需要一些外徑為2m，長度為 25～ 35m 的鉆孔（ CIDH）轉(zhuǎn)動軸。多方位的弧形軸承用在墩位和支座上以適應(yīng)其運動。很多結(jié)構(gòu)系統(tǒng)需檢查，包括主要的可變因素，如塔的結(jié)構(gòu)、斜索的構(gòu)造、橋跨的 設(shè)計、上層結(jié)構(gòu)的交叉段以上述結(jié)構(gòu)的支撐情況。以及一系列由三方面因素延遲時間估計，即該段估計時間被認為是由 SEE 和 FEE 地震產(chǎn)生的運動從一個點傳到下一個點的時間假設(shè)地震波速度和塔柱之間的距離計算得到。這個估計確定了地震和對應(yīng)的地面震動在水平方向的往返時間。然而，在初步設(shè)計階段進行的地質(zhì)勘測和鉆孔取樣表明運河東部和西部堤岸的地質(zhì)和土壤條件很不一樣，也就是塔柱坐落處。 ● 路緣能容納 寬的人行道。因此，橋梁設(shè)計的完成與施工聯(lián)系在一起，整個工序類似于設(shè)計 — 修建。百年大橋（為紀念巴拿馬人民獨立 100 周年而命名）已經(jīng)開始修建。the probability that it will be exceeded within 50 years is 2 pencent and within 100 years,4 persent. Because of uncertainty about the direction from which the seismic waves would approach the site, a single response spectruma curve showing the mathematically puted maximum response of a set of simple damped harmonic oscillators of different natural frequencies to a particular earthquake ground accelerationwas used to characterize mitions in two mutually orthogonal directions in the horizontal conduct a timehistory analysis of the bridge’ s multiple supports,a set of synthetic motions with three ponentslongitudinal,transverse,and verticalwas developd using an iterative ground motions from an earthquake in Chile in 1985 were used as “ seed” motions for the sythesis process. A time delay estimatethat is,an estimate of the time it would take for the motions generated by the SEEand FEE earthquakes to travel from one point to the nextwas create using the assumed seismic wave velocity and the distance between the piers of the an assumed was velocity of approximately ,a delay on the order of half a second to a second is appropriate for a bridge 1 to 2km long. Soilfoundation interaction studies were performed to determine the stiffness of the soil and foundation as well as the seismic excitation measurement that would be used in the dynamic studieswere conducted by means of soilpile models using linear and nonlinear soil layera of varying equivalent pile lengths in the studiesthat is, the lengths representing the portions of a given pile that would actually be affected by a given earthquakeinduced ground motionranged such a threedimensional model,there are six ways in which the soil can resist the movement of the lpile because of its stiffness:throngh axial force in the three directions and through bending moments in three the bridge site contains so many layers of varying soil types,each layer had to be represented by a d