SYSTRA的创新设计——U型高架结构
SYSTRA's innovation – U - shaped elevated structure

SYSTRA公司在总结城市轨道交通高架形式的基础上，经多学科工程专家共同努力，开发的u型高架结构形式，特别适用于城市轨道交通，符合现代化城市发展对景观和环保的需求。其主要特点如下：
On the basis of summarizing the elevated structure forms of urban rail transit, through the joint efforts of multidisciplinary engineering experts, SYSTRA developed the U - shaped elevated structure, which is especially suitable for urban rail transit and complies with the needs of landscape and environmental protection for modern urban development. Its main characteristics are as follows:

● U型高架的主要特点 Main Characteristics

1.改善城市景观 Urban landscape to be improved

传统的箱型结构断面，桥面板的厚度通常在1.5米至2.3米之间。而U型结构，其轨下结构的厚度（结构底板的厚度），在0.22米至0.35米之间。因此，使轨道高度降低1.2米至2米，车辆的下部在U型槽里，有助于减少高架结构对城市景观视觉上的影响。
For the cross sections of traditional box structure, the depth of deck is usually between 1.5 m and 2.3 m. But for the U-shaped elevated structure, the depth of the structure under the rail (the thickness of the slab) is between 0.22 m and 0.35 m. Therefore, the track top level is reduced by 1.2 m to 2 m and, the lower part of the train is inside the u-shaped structure, which can help reducing the visual impact of the elevated structure in the urban landscape.

2. 隔音效果良好 Good sound insulation effect

由于车辆在U型结构内走行，U型结构腹板起到的隔音效果胜于传统的隔音屏。
Since the trains run inside the u-shaped structure, the u-shaped structure's web plays a better sound insulation effect than the traditional sound insulation screen.

3. 车站设计简化 Station design to be simplified

典型的U型结构在穿越车站时可以与车站结构完全分离，即车站主体结构基本上由U型结构本身组成，这将可以使整个线路的结构底板保持一致性。

车站的其它结构，例如：屋顶、售票大厅、设备用房等则可以在主要结构之外独立建设。
The typical u-shaped structure can be completely separated from the station structure when passing through the station, which means, the main structure of the station is basically composed of the u-shaped structure itself. This will allow the structural slab to be consistent for the whole line.
Other structures of the station, such as roof, ticketing hall, equipment room, etc., can be built independently of the main structure.

4. 施工灵活方便 Flexible and convenient construction

U型结构的施工可根据项目现场的实际情况，采用整体预制、分段预制、现场拼装或现场浇注等不同的施工方法。此外，U型结构还有施工周期短、施工期间对地面交通影响小、施工地点灵活的特点。
According to the actual situation of the project site, the construction of the U-shaped structure can adopt different construction methods such as full span prefabrication, segment prefabrication, on-site assembly or on-site casting etc. In addition, the construction of U-shaped structure has the advantages including short construction period, little impact on ground traffic during construction, and flexible construction site.

5. 降低工程造价 Project cost to be reduced

由于结构高度的降低，车站的高度也因此下降。显然可以降低工程造价（如可以节省自动扶梯的费用等）。另外，混凝土底板的造价与传统箱型梁相比也降低了。总体的工程量与投资成本可以节省20%以上。
As the height of the structure is reduced, so does the height of the station，that can obviously reduce the cost of the project (for example: cancellation of the cost of escalators, etc.). In addition, the cost of concrete slab is reduced compared with traditional box beams. Generally, the total project volume and investment cost can be saved more than 20%.

6. 设置安全通道 Easy to set up the safety evacuation walkway

U型结构侧壁上部与车辆地板等高的层面上可以设安全通道，方便乘客在紧急情况下的疏散。这是U型结构从安全角度考虑设计，这是与传统高架结构相比最为显著的优势和特点。
The safety evacuation walkway can be provided on the upper part of the web of U-shaped structure, which is at the same level of the train floor, so as to facilitate the evacuation of passengers in case of emergency. This is a specific design of U-shaped structure for safety reasons. This is the most significant advantage and characteristic compared with the traditional elevated structure.

7. 防止脱轨装置 Derailment prevention device

在高架桥上，必须设置防脱轨的装置以保证安全。常规结构通常需要使用混凝土的防脱轨墙或护轨。而U型结构中，由于车辆位于结构侧壁之间，因此不需要其它辅助的防脱轨装置。
Normally, on the viaduct, anti-derailment devices must be installed to ensure safety. Conventional structures usually require the use of concrete derailment walls or guardrails. For the U-shaped structure, since the train is located between the webs of the structure, no additional derailment prevention devices are needed.

8. 设备集中布置 Centralized arrangement of equipment

信号设备、通讯设备、电缆等都可以安装在U型结构的侧壁上，减少空间的占用，方便设备操作和维修。

基于以上这些优点，U型结构作为一个先进的设计，将在城市轨道交通中占有重要的位置。
The equipment for signaling and communication as well as the cables can be installed on the web of the U-shaped structure, which can help reducing the space occupation and facilitating the operation and maintenance of equipment.
Based on these advantages, the U-shaped structure is considered as an advanced design, which will play an important role for the development of urban rail transit.

● 项目实例 Reference