Dawlish sea wall – section two

The railway is a vital artery, which connects communities, businesses and visitors in 50 towns and cities in the South West with the rest of the UK. Since the damage caused by heavy storms which resulted in an eight-week closure of the railway in 2014, Network Rail has been developing plans to improve the resilience of the railway between Exeter and Newton Abbot.

TheSouth West Rail Resilience Programme成立以确定和实施改善DAWlish和Teignmouth之间的轨道恢复力的最佳选择，有助于避免重复2014年的事件。

Following the events of 2014, we undertook a complex and expensive repair operation to reinstate the line between Dawlish and Teignmouth, this work cost more than £35m.

Since then, 2014 we have been working continuously on the line and putting together plans to safeguard it for future generations. This includes three studies in 2014, 2016 and 2018.

In November 2018, a nine-month plan of work began to repair the breakwaters at Dawlish.

2019年初，运输部致力于为Dawlish的新海墙致力于80米，从海岸守卫堤防到2019年夏季，我们开始在海洋游行的第一个部分工作。

We have now developed plans for the remaining section, which is to be built between the Coastguard and Colonnade breakwaters, a 415m stretch between the 2014 sea wall work and the current Marine Parade scheme.

With the support of world leading coastal, marine and railway engineers we have been investigating the best long-term solutions to make this section of the railway more resilient.

We believe the option we are proposing – a new, taller sea wall with high-level promenade – offers the best solution between the Coastguards and Colonnades breakwaters.

There are a number of varied engineering challenges along this 415m stretch, including the Grade II listed Dawlish station building; Dawlish Water stilling basin, where the stream runs out into the sea; and the town gateway.

We undertook a full option-selection process, which considered a series of potential solutions. These included combinations of the following to deliver the required resilience:

• Offshore breakwaters
• 护岸
• Raised sea wall with high level promenade
• Raised sea wall with low level promenade.

在下面的选项选择报告中提供了完整详细信息。

• Option selection report Dawlish Sea Wall Phase 2 (PDF, 4.22 MB)
• Offshore breakwaters technical note (PDF, 4 MB)

为了确保我们找到了对DAWlish铁路海防的合适恢复力解决方案，网络铁路与HR Wallingford一起使用，这是一个全球公认的领导者解决挑战，随着水与人，基础设施和环境互动。亚搏彩票软件官网HR Wallingford的主要工程师蒂姆·普伦博士，负责改善DAFLish中的改善铁路复原力的解决方案的项目主任解释了他们的研究结果;是否有“完美的海防”这样的东西;以及为什么其他选择折扣。

Part 1 – Findings and solutions

Part 2 – Promenade level

Part 3 – Perfect sea wall

新的较高的海墙，具有高水平的散步，将建在混凝土预铸造面板中。它将从新的斜坡/访问中奔跑，这是在Dawlish站的西端建造的，一直到海岸守卫堤防。

The new wall will add 4.2m to the height of the current 3.8m promenade, and its toe will extend, on average, 2.8m further out towards the sea. The wall includes a recurve at the top, as at Marine Parade, to help deflect waves and reduce ‘overtopping’ of water onto the track.

新的高级散步，它将与当前平台大致相同的高度，将为用户提供更宽敞的更安全，水平的表面。它比电流散步（从3米到4米的不同）宽，用户将由海侧上的弯曲的栏杆墙保护，围绕腰部高度（1.1米）。这是墙体整体高度的一部分。

There will be a number of raised points with benches along the promenade. This will allow more people to enjoy the views as the parapet will be reduced to 0.8m with a small railing on top.

In addition to the sea wall itself, the project also includes the Grade 2 listed railway station. The existing platform, a timber construction, overhangs the sea wall and has been rebuilt many times in the past due to sea damage.

该平台将被重建并重新调整，以使人们更容易进入和关闭列车，因为从平台到培训平台将减少。这对轮椅/俯卧撑用户来说尤为重要。

Although the view of the station building from the beach will be partially obscured by the new wall, the structure will protect it from the elements and protect it in the years ahead. Increased resilience will also give the potential for parts of the building to be brought back into use.

The new footbridge will feature both steps and lifts, helping passengers with disabilities, wheelchairs, pushchairs and heavy luggage.

The design proposed is the result of a national Network Rail competition with the input of the Design Council. However, due to the harsh coastal environment, the favoured design has been adapted to include higher specification motors and electronics. In addition, at the side of the steps to the seaward platform, we need to incorporate a solid wall to provide shelter from the wind and water from the sea.

当前的人行桥仍将作为一个integral part of the station platform buildings for those that wish to use it.

在该方案的南端，目前对毗邻车站建筑物的海滩的倾斜进入将被坡道替换。在该计划的北端，将更换现有步骤。

South of the station, the new high-level promenade will continue onto a new footbridge, running parallel to the existing Colonnade viaduct.

The bridge will link the second section of the new sea wall and promenade to the first,
目前正在海洋游行建设。

另一端，它将提供直接连接到车站平台和向海岸窗口的新高级散步。

To improve resilience, we will reconstruct the existing ‘stilling basin’ boundary wall on its existing footprint with a much stronger structure.

这将从波浪中取出能量并延长盆地的寿命。能源的减少将减少在高架桥下存放的一些海滩材料，并保护新的链路桥和现有结构。

根据海平面上升，可以在30至40年内需要进一步努力盆地。我们正在进行建模以评估这一点。

To achieve the level of resilience required by providing a much higher sea wall, we need to demolish the Coastguards boathouse owned by Network Rail to enable us to increase in height of the promenade/sea defence.

A footprint will be left to show where the building stood and we plan to reuse the stone in constructing new public benches within the project.

We’ll also need to adjust the bottom section of the existing footbridge steps at this location.