工程学：阿基米德桥（Submerged Floating Tunnel,简称SFT）

Engineering: Archimedes Bridge, a Submerged Floating Tunnel (SFT)

沟通某片海域的支流两岸，或者连接湖的两端，这曾是人类不得不直面的难题。为了解决这个难题，人类学会了搭建桥梁。随着时间的流逝，这些桥梁变得更加坚固，外形也变得更加雄伟壮观，而随着筑桥技术变得越来越精密复杂，桥的跨度也变得越来大。不过，无论这些桥梁设计是怎样的前卫大胆、充满创新精神，都离不开一位生活在很久很久之前的天才所研究出的原理，这位天才就是生活在公元前二世纪的阿基米德，史上最伟大的科学家和数学家之一。

我们首先从关于海峡大桥的研究谈起。海峡大桥用来连接意大利半岛和西西里岛之间3千米长的海峡。不过之后人们研发出一种可以取代传统水上桥梁的新型桥梁，我们姑且可以把这种它称作“海峡下的桥梁”。这种桥梁彻底颠覆了传统筑桥的固有模式，水不再是需要被克服的障碍，相反，通过自身的推动力作用，水成为加固桥梁的因素之一。这种“水下桥”的结构创新之处在于，桥梁并不处于海底，而是浸没在有一定深度的水下，但是同时又不会影响海面上船只的自由航行。这种桥梁由多段隧道集合而成，这些隧道被流线型的罩子密封起来，被固定在海底的钢缆紧紧拉住。这种桥梁在耐受性方面更具优势，

因此近几年国际上有关这种新型桥梁结构的研究不计其数。不过这种结构基本原理的发现得益于古代天才阿基米德的灵光一闪。早在公元前二世纪，这位来自古希腊锡拉库萨的科学家就根据直觉断言“水中的物体受到向上的浮力等于它排出的水的重量”。为此，中意阿基米德桥联合实验室(Sino-Italian Join Laboratory for Archimede’sBridge ,简称SIJLAB）得以建立。这个实验室以那不勒斯腓特烈二世大学为首，主要目的是完成连通中国千岛湖的阿基米德桥的模型构建工作。

Connecting the shores of a river or of a lake has always been a challenge that man had been facing by inventing ever more brilliant, spectacular and increasingly complex technologies. Yet the most innovative and futuristic system is based on a very ancient principle studied by the great genius of Archimedes, who is considered one of the greatest scientists and mathematicians in history, lived in the 2nd century BC.

From the study carried out for the so-called Bridge on the Strait, designed to cross the 3 km long sea stretch that divides the Italian peninsula from the island of Sicily, an alternative solution to the traditional suspended bridge has been developed. And we could call it the Bridge under the Strait. It completely changes the philosophy of the project: water is no longer an obstacle to overcome, but rather an element that contributes to the stability of the bridge through the push it exerts on it. Archimedes Bridge is conceived to interact with water itself. The innovative structure consists in a submerged bridge that is nor subterranean neither does just lie on the bottom but floats at a depth compatible with free navigation, and consists of some tunnels integrated in a hydrodynamic gasket tinned by steel cables hooked to the bottom. The cross section is defined by functional, static and hydrodynamic parameters, including the floating ratio that depends on weight and volume. Depending on the severity of the underwater environment, the anchors may be of different type: cables, bridges, rigid elements or piles.

In the last few years a number of international studies have been carried out, the most significant ones in Italy, China, Japan, South Korea and Norway, to study the bridge innovative structure, in order to investigate the advantages in terms of sustainability. These studies has been motivated by an interest in the great structural and sustainability advantages as well as the modularity of the structure, which implies the possibility of achieving the Archimedes Bridge without any length limit and with a drastic reduction of the traditional construction times and costs. An innovative concept but based on a very ancient principle, the intuition of the genius of Archimedes, a Greek-Syracuse scientist who back in II century B.C. had already discovered that "a body immersed in a fluid receives a push from the bottom upwards equal to the weight of the volume of liquid shifted". In particular, the SIJLAB - Sino-Italian Join Laboratory for Archimede's Bridge, an experimental laboratory led by Federico II University of Naples and Politecnico di Milano, Chinese Academy for Sciences and Archimedes Bridge Society S.p.A, has been created with the aim of designing a 100mt prototype bridge to cross the Qiandao Lake in China, as an experimental support to technological development.

Curator               

Beatrice Faggiano – Università Federico II Napoli
Alessandra Fasanaro, Bruno Discepolo, Giovanni Aurino - Ado Architecture design organisation

special thanks to            
- Alessandro Rugolo, Giorgio Onda, Giovanni Santoro
Università Mediterranea Reggio Calabria
- Rollin & Rollin