隧道的最初目标是穿越障碍(一般是山),但是,最近几年伴随着大量的日益复杂的操作设备(通风系统)和操作方法的引入,隧道已经变得越来越复杂。能够操控成千上万的项目,包括控制系统、检测系统和运营,由此带来了日益复杂的各种管理运营情况。
图1.0 : 圣哥达隧道火灾
继勃朗峰隧道的灾难之后,1999年陶恩隧道和2001年圣戈撒德隧道也发生了火灾,整个系统与安全相关的所有方面被加强,并因此形成了个安全系统的整合。从工程的设计开始就有了更多的限制规定,这些限制规定对土木工程所有设备都有一个重要的影响。
隧道被普遍认为是“造价高且风险大的工程”,对于它的建设和运营管理都是如此。这一背景使得一些国家在建造第一条道路或铁路隧道时很不情愿。为了解决这一问题,即降低建设和运营成本,控制建设中的风险和运营中的火灾意外,优化隧道设计、建设和运营过程中的每一步就显得越来越必要。当考虑到建设和融资模式时,这种风险和成本的控制得到加强。现在的建设融资模式有特许模式、设计建造模式(或叫私人公营机构合作模式),越来越多的使用这些模式就使得风险和成本的控制更为加强。
第一章的目的:
这一章不是宜隧道业主所需的行动的详细手册,或设计师实施的技术规定,或确定的任务,以确保运营商,以确保安全和舒适的隧道为目的。第一章不是一个设计手册。它的目的是提起读者的注意,以方便他们的做法和对这一复杂领域的理解,确保他们能够避免许多操作不当引起的不幸的失误,并使他们能够察觉到可能优化。
本部分文献由伯纳德法卡特(法国)编写整理,伯纳德法卡特先生是隧道分会的法国代表,同时兼任第五工作小组成员,并将其法文版本的手册翻译到目前的英文版本。
最初的法文版本由迪迪拉克尼斯(法国)和威利德拉斯韦尔(比利时工作委员会的世界隧道协会代表)进行修定。
本章的英文版本由路斯儒(法国)和范西特纳达(美国)审核。
一个隧道,构成一个“复杂系统”,这是把非常多的参数考虑进来的结果。这些参数的影响因素通过下图(图1.1-1)可以看出。
所有这些参数在各因素的影响下是可变的和相互影响的,就像各个因素也是变化的一样各个参数之间的相对权重,各个参数的性质由于个隧道的情况不同而或多或少的不同。例如:
图1.1-1 : 复杂隧道系统子集组成示意图
注释1:简图布局有多种且往往是可转换的,该简图中,隧道的总体思路和功能区是放置在草案的中心。也可以制定当其他因素放置在草案的中心时的类似的图表。
注释2:第一圈代表技术领域,主要因素表示以下几个方面:
注释3:第二圈代表即将建设工程的修建环境,主要因素包括以下几个方面:
一条新隧道(或者一条就隧道的维修)的设计需要考虑很多很多的参数。决策树中相关的参数非常复杂,且需要多领域有经验的各方进行确定,由于以下原因,各方应尽早考虑并确定相关因素:
每一座隧道都是独一无二的,应针对其具体和独特的条件进行分析,这些专门的分析结果是针对具体条件建立隧道提出合适的解决方案必不可少的,并且可以达到以下目的:
对于多数隧道,不存在复杂的"魔幻版的关键技术",也不是简单的将方案进行复制和粘贴,隧道的设计和优化需要开展以下工作:
下面的几个段落将用来阐述分析中参数间的作用特征,分析其相互特征及往复循环特征。
尽管上述事例不够详尽,但是他们的目标是让读者认识到这些问题,并尽量针对具体隧道考虑这些问题。
1.1.2.1. 参数分析
表1.1-1与土建工程相关的各个方面的主要技术参数。
1.1.2.2. 不同参数间的互相作用
不同参数间的相互作用较为频繁,且这些影响考虑到了不同参数间的交叠。
下表1.1-2举例列出了通风、断面和安全方面参数的相互作用:
表中显示了若干个列中都有同样的特定的参数(见连接线),这样就建立了不同参数子集中参数间环状相互作用。这些相互作用通过复杂的函数来确定,所以一般想利用简单的纯数学公式来解决是几乎不可能的。该问题的解决要求的各种参数之间的层次结构的定义,然后考虑到更高层次的参数的假设。这个层次不同于一个项目到另一个,例如:
结果的过程是交互式的,且如前面的例子中展示的,是基于一组假设的基础上的。这个过程需要技术人员宽泛的、多学科的工程经验,从而能够充分将工程中的相关参数纳入到这个连续的过程中,确保服务水平和安全水准的基础上,能够优化整个工程。
表1.1-3显示了通风系统各个方面主要技术参数的关系,但并不详尽。
对于土木工程,不同参数间的相互作用是非常多的,这种作用也是循环作用的关系。
解决问题的过程与上述描绘的土木工程中的方式是类似的。
除以下内容外,运营部分并不是功能定义的关键参数:
“运营设备”的组成在另一方面来说对技术性建筑物的入口,地下机电分站,所有的地下技术空间,或者各种设备,凹处和壁龛的尺寸的一个重要参数。关于温度,空调以及空气质量往往需要安装特殊的设备。
从建设、运营和维护费用的角度来讲,这些也是非常重要的。
隧道运营设备对于隧道安全来讲也是必不可少的,并按照以下目标进行设计、建造和维护:
1.1.5.1. “安全”概念
图1.1-5 : 影响安全因素
在建设成本方面基础设施是一个重要参数。但是在基础设施上投资太多的钱而没有使重要的设备提高安全条件则是没有考虑到以下几个方面:
1.1.5.2. 如何进行隧道工程的参数影响分析?
对于一个隧道工程,这些参数或多或少都会影响到隧道的青年,下表给出了一个简例。
注:下面的四张表指的是图1.1-5中的4个主要领域:
基础设施 | 影 响等 级 | (主要影响因素)注解 |
---|---|---|
逃生路线 | 隧道内 -平行导洞 - 直接外部通道 - 连接两洞之间的横通道 | |
紧急团队通道 | 来自另一洞 - 专用通道 - 普通逃生路线 | |
多人逃生 | 逃生路线规模 - 连接隧道的间距 | |
通风 | 通风概念 - 在一定运营和交通状况下,纯纵向通风系统的局限性 |
运营 | 影 响等 级 | (主要影响因素)注解 |
---|---|---|
反应计划程序 | 发信号 - 监测控制和数据采集 - 与用户的沟通 | |
干预营救队 | 洞口建筑尺寸 - 最终的地下设施 - 专用工具 - 水箱大小 | |
团队培训 | 特定的外部设备- 专用软件 |
车辆 | 影 响 | (主要影响因素)注解 |
---|---|---|
平均和峰值小时交通量 | 车道数- 通风概念和大小 | |
危险品运输 | 通风影响 -特定危险货物泄漏的排水系统 - 在消防队陪同下特定护送的运行程序--> 停车设施和人员 | |
车辆状态 | 特定状况下, 在进入隧道前尺寸控制和热控制 --> 门框热控制 + 停车 + 人员 | |
特定车辆类型的限制 | 例如: 城市隧道用于轻型车辆 - 隧道的尺寸, 通风逃生路线 |
道路用户 | 影 响等 级 | (主要影响因素)注解 |
---|---|---|
信息咨讯 | 进入前散发传单-电视宣传 | |
"实况直播" 通讯 | 发信号、 速度测量系统、 收音机广播、交通指示灯、横截面的影响、 机电系统、 数据采集与监控系统、有时远程的路障 | |
教学 | 驾驶学校(在一些欧洲国家) | |
逃生路线指导 | 发信号- 栏杆 - 闪光 - 噪声 - 对机电系统和数据采集与监控系统的影响 | |
车辆之间速度和距离的控制 | 雷达和间距探测器 - 对机电系统和数据采集与监控系统的影响 |
隧道是一个复杂的系统,特别是:
由于隧道设计中缺少隧道文化,没有考虑相关因素,导致了许多问题的处理是片面的,不周全的。
对隧道这个复杂的系统的设计进行进行控制很复杂,但是必须的,特别是:
通过早期清晰的功能定位和价值工程程序,可以确保这个复杂系统的得到控制,同时可以使工程的投资和技术方案得到优化,从工程的开始,应考虑到以下相关因素:
这些因素的考虑是确保整个系统的设计问题解决的有效方法。
第1.2节主要涉及的新隧道的设计问题。设计主要是关于运营隧道的重新装修、安全升级等问题,相关内容在第1.3节中有描述。
公路或高速公路隧道纵向和横向线形的设计,是新隧道设计主要和基本过程,但是缺乏必要的重视。
将隧道作为复杂系统进行考虑必须在整体方案设计的最初阶段进行,即隧道线形设计阶段就要考虑,但是实际上一般没有做。因为在线形规划阶段,技术和投资优化工作是最重要的。
在工程最早的阶段,非常有必要动员一批经验丰富的多学科专家和设计师,他们将帮助识别出项目的潜在问题,即使初期缺乏初步的信息和数据。这个专家组会对主要问题作出可信且有益的决定,这将有助于充分利用现有的信息。
本节的目的不是指出隧道布局设计的规则(第1.6节参考了几个国家的设计手册),而是使业主和设计者在设计的早期对全球性和多文化的方法及从工程中获取的经验是工程成功的首要因素的重要性有充分的认识
1.2.1.1. 无"隧道文化"的国家
这些国家隧道业主和设计者对于隧道理解有一定理解,他们更愿意将隧道理解为穿越山岭的"魔术般的布局",穿越陡峭山岭,有着陡峭的梯度,有较大的挡土墙或很长的高架桥,穿越活动滑坡地区的时候需要做大量的加固工作(这些加固工作非常昂贵,且不会有很长的使用寿命)。
通过多个对采用系统全局设计方法施工的工程和未采用系统全局方法设计工程(包括隧道和线形)的实例对比可知:
通过外部评审员的协助减轻了"隧道文化"的不足或者缺少,从而提高了工程效率。
考虑工程总体优化的集成方法很少能够得到采用,反而将隧道断面作为固定几何形状的线形专家,而没有考虑到隧道整体设计中的诸多约束因素和要素。
非常有必要在本阶段将1.1段所有参数及接口考虑在内,特别是:
1.2.2.1. 具体问题
选线完成后,功能性横断面构成了的隧道设计的第二个重要阶段。对于第一阶段,"复杂系统"的做法,必须考虑在一个非常细心的方式下进行,尽可能与有经验的多学科小组一同成为上游。第1.1节所述的参数和接口都必须考虑。
第二个阶段(功能性横断面)和第一个阶段(定线)并不是相互独立的,显然,必须考虑到由此产生的规定。这两个阶段是相互依存,密切联系在一起的。
另外,如1.1.2.2.段所述,前两个阶段的过程是迭代和互动的。没有直接的数学方法,能给出一个单一的答案来分析"复杂系统"。也没有唯一的答案,但有有限数量的好答案以及大量不好的答案。要尽快确定一个好的解决方案,多学科团队的经验是必不可少的。
在第1.2.1.段所引述的例子说明"功能性横断面"的规定,对平纵面线形设计有着重大影响。
经验表明,"功能性横断面"的分析往往是不完整的,仅限于土木工程的唯一的规定,从而不可避免地出现:
1.2.2.2 重要条款
隧道功能性横断面形状的主要参数如下:
1.2.3.1. 一般规定
国际路协的建议很多是关于安全性和安全考查操作、组织操作和应对突发事件以及操作的规定。(内容详见:第二章"安全性"和第三章"人为因素对隧道安全性的影响")
本章主要介绍"复杂系统"的安全性和操作接口。1.1.5.2.节的表格表明了工程不同部分参数的相互依赖程度。
一部分参数很受工程中上一环节的影响。以下这些参数必须从第一步设计阶段开始分析并且特别处理:
这些重要的隧道设计参数也是进行 "危害分析"的必要组成部分以及"紧急救援队伍介入营救"的初步草案。这就是为什么我们认为"初步风险分析"是很重要的,在刚开始的设计阶段即需要进行"紧急应变计划"初步分析。这种分析可以更好地描述隧道的具体特点和必须满足的安全规范。它也有助于进行价值工程分析、优化设计以及最佳化资金运用。
接下来的段落较为详细地介绍了这些参数和它们的影响。
1.2.3.2. 与交通相关的参数及其意义
这些参数主要影响隧道功能性断面尺寸,且部分影响了断面的布局:
1.2.3.3. 用户的撤离与抢救队伍的进入
用户的撤离和抢险队伍的进入参数是功能性条款和总体设计的一个基本要求,这个要求经常影响布局(直接通往外界的出口)及建设的相关要求:横洞、下穿洞、平行导洞、逃生避难所的连接通道。
分析要求建立集成的通风设计方法(特别是火灾情况下的通风方案)、流量分析、风险分析、紧急情况下响应方案的草案(特别是通风、救援场景的调查)、和施工方法。
所以,非常有必要从功能的角度定义路线、几何特征及空间布局,以确保紧急情况下正常人和残疾人能够正常流动。
所以,应该保证这些设施具有统一性、可获取性以及设备具有缓解紧张情绪、使人乐于获取等特征。这些设备是用户在非常紧张的情况下使用的,设备的简单、易用、具有缓解紧张情绪的功能,可以避免用户的紧张情绪转化成恐惧心理。
1.2.3.4. 通风
通风设施设计为纯粹的纵向通风系统,且对隧道功能断面和线形均无影响的通风系统。
这里指通风系统的并非纵向由配有抽排管道设备,或横向通风系统、半横向或半纵向系统和混合系统,也不是利用竖井、连接通道等非洞口方式进行抽排的通风系统。所有上述的系统均对隧道功能横断面和线形及附加的地下结构均的设计有很大的影响。
交通区域通风设施设计的实际目的在于:
通风系统可以同时具有以下功能:
通风系统不仅与交通区域有关,还与以下因素有关:
设计的通风系统应具有以下功能:
1.2.3.5. 与用户的联系及监管
信号指示中的与用户相互联系对隧道功能性横断面有重要影响。
通讯系统对"复杂的系统"总体不产生的重要影响,而与操作系统相关的子系统有直接关系,特别是远程监控、探测、联系、交通管理控制和监管以及紧急撤退的组织工作。
1.2.3.6. 运营的特别要求
隧道的运营和养护组的工作均需要作出专门的工作安排,确保相关工作能够在完全安全的环境下进行,且减少对隧道的正常交通影响。这些专门的工作安排包括:在地下的设施前面设置紧急停车道(带),为设施的常规维修、材料(特别是重量较重或不方便操作的材料)的更换和维修服务。
本节的主要目的不是详细介绍操作的设备器械、功能及设计。这些要素的定义在目前的公路隧道手册的标准以及相关的手册、第1.6节中列出的国家标准中。
主要的目的在于引起隧道业主及设计者对隧道运营的设备和仪器的重视。
1.2.4.1. 重要选择
隧道的运营设备应该能够隧道有效发挥其功能,保证隧道交通通行,满足车辆通行时能够提供安全、舒适的服务。
运营设备能满足隧道功能:适合其地理条件、其内在特质、交通车辆类型及隧道进出口两端基础设施的类型,以及紧急情况下救援安排和隧道所在地国家的规定和文化。
隧道运营系统过度并不自动提升隧道的服务竖排、安全性和舒适性。相反,这需要加大对这些设备维护和人为干预,否则反而可能导致隧道安全水平的降低。相关设备的并置或过度使用是无用的,这些设施应该相互匹配、互补、适度冗余(确保起到安全作用)且整体具有连贯一致性。
运营设施是"活"的:
基于以上的考虑,主要的战略选择有以下几个:
1.2.4.2. 关键设备的主要要求
1.2.4.2.a. 能源-电源-电力的分布模式
需要隧道正常的运营,必须有正常的电力供应。长大隧道可能需要几个兆瓦的电源供给,这种供给一般现场很难直接解决。从隧道设计的早期阶段即应该特别安排来加强利用已有的电力网络,或创建相关电力网络。电力网络对于隧道的建设和运营是必不可少的。
电力的供给及配置应该满足:
隧道的特殊性决定应对隧道的地理特征、现有电力网络、电力供给特征(优先特性)、现有电力网络的可靠性以及是否可能增加网络的电力供应、隧道特有的风险及紧急服务时需要干预工作的条件。
相关的设施可以对应进行设计,并且根据系统的可靠性和设计阶段的决策来实施运营程序。
隧道在缺乏电力供给时的安全目标:
电力供应主要通过以下措施得到实施:
1.2.4.2.b. 通风
在通风领域,相关的世界道路协会的规定是比较多的,对于世界上通风设施的概念和设计有重要的参考意义。除了上述的1.2.3.4节外,读者还可以参考第8.5节。
但是,值得指出的是,通风设备仅仅是保证隧道内运营环境健康、舒适和安全的一个基本要素,它仅仅是由用户、操作员、紧急救援组等诸多人员的行为、专业技术和行动能力构成的复杂系统中的一环。
通风系统自身不能满足设想所有的场景、所有功能,特别是有关环境保护和空气净化相关的功能。
通风系统及定位的相关选择需要丰富的经验:封闭空间中流体力学现象的理解、火灾发展的多个步骤、辐射和热交换,以及燕窝等有害气体的产生及发展。
通风系统消耗能量巨大,应特别注意他们的尺寸和操作的优化,譬如采用专家系统。
通风系统一般来讲非常复杂,相关的火灾情况下的管理实施需要安装自动系统,以期自动管理和掌握现场情况,这中操控比操作人员在巨大压力下进行操作能够更加高效。
在第1~4节中表明的,通风系统必须首先满足正常运营情况下的健康、卫生要求,以及紧急状况下的安全要求。
耐用性、可靠性、实用性、寿命及消费能源类型等要素构成了通风系统需要满足的条件。
1.2.4.2.c. 通风设备的附加设备
如果股东、居民团体或强烈游说的存在,可能需要安装以下两种附加设施:
A. 空气清洁设施,
读者如需阅读相关内容请参考第5.1节。
空气清洁系统的实施是当地城区环境保护组织的不断要求下进行的,这些设施通常安装在地下,这些设备的建设、运营和维护通常非常昂贵,且耗费大量的电能。
目前其效果也不是太令人信服,特别是重要的汽车尾气排放减污,且这是设备很难彻底清除隧道内污物含量不高的空气,所以最近十年安装的清洗系统基本上都没有正常工作。
在存在严格的规定的国家,严格要求从根源上消除污染排放,这种清洗设备的前途是不够明朗的。
B. 固定灭火系统(FFSS)
第8.7节主要介绍该部分内容,需要的读者请阅读相关章节。
具体技术有很多种,对于不同的技术标准回答也不同:灭火-控制火势-减少处于附近用户处的热传递和温度-保护衬砌结构免受高温破坏等。
这些系统,即使都有各种的优点,但是都有一个特别的缺点即是隧道内的视线环境变得更差,特别是火灾刚刚开始时,固定灭火器需要一个内在一致的方法确保用户所有方面的安全,这个方法应同时与保持通风和紧急撤离相一致。
决定是否实施这种系统的决策是异常复杂的,且会产生非常严重的后果。这种决策应该是通过通盘对安全的特殊要求及该系统带来的附加效果的思考的基础上进行的,而不是由于一种流行或经他人游说产生的结果。
固定迷惑系统需要重要的维护措施的实施,需要经常进行测试,否则无法确保其可靠性。
1.2.4.2.d. 照明
国际照明协会(CIE)的标准遭受了世界道路协会的批评,因为其规定往往导致过度照明,读者请参考欧洲标准委员会出版的技术报告中推荐的几种方法,其中包括CIE推荐的方法。
照明是确保隧道内安全和舒适的基本工具,照明的基本目的应适应隧道的地理条件(是否城市隧道)、隧道特征(隧道长短)、车辆类型和特性。
照明系统消耗大量的能源,新的技术正在发展来优化其特征和性能。
1.2.4.2.e. 数据传输检查(SCADA)
数据传输检查(SCADA)是隧道的神经系统和大脑,允许数据信息的编译、传输,并传输对仪器发出的操作指令。
系统需要谨慎的对隧道内的根据细节进行分析,其中包括隧道的运营的模式和组织、隧道所处环境带来的风险、救援干预的实施程序和安排。
应该根据隧道(群)特殊的环境、必须的人员和材料、将要起到的作用、发生事故时自动设备和专家系统对操作人员带来的实质帮助等要求,监管和控制中心的组成进行详细的分析,以期达到简化和减少操作人员的工作任务,提高工作效率的目的。
系统的详细设计需要时间长,过程复杂,需要对系统开发、不同阶段的控制、试验、现场安装后全局控制等有严格的方法论,经验表明这些系统中诸多的错误原因有以下几点:
手册的第8.2节总结起来就是这几个方面的内容。
1.2.4.2.f. 无线电传输-低电压回路
这些设备包括:
1.2.4.2.g. 信号
信号的具体含义见第8.9节。
比其他设施更明显的是,信号信息的过于繁多或冗余对于其相关设备和目标是不利的。
隧道信号体系的可识别性、同质性和层次性是隧道信号洞内、洞口段信号设计的首要任务,甚至比灾害情况下向用户发出紧急撤退的信号还要重要。
固定信号面板,车道信号,可变信息的信号,交通灯,停车灯,紧急出口的信号,那些出口的特定信号,信号的安全区域,关闭通道(可移动的障碍)的物理设备,水平标记和横向警示条都是信号装置的一部分。他们确保了与用户的部分联系。
1.2.4.2.h. 灭火器
火灾探测器可能是布于局部的空间(探测地下子站或工作室),或线形分布在交通通道空间中。
防火器械有很多种:
1.2.4.2.i. 其他各种仪器
另外,还可以针对隧道安全、舒适、结构保护的需要有针对性的安装其他设备,例如:
已有运营隧道的升级与装修可能会产生新的分析和解决问题的方法。这时限制的条件比新建隧道要多的多,因为应该将已有空间和限制等问题进行考虑。相关设备及集成的技术差不多是相同的。
隧道运营状态下进行更新和升级往往导致工期和费用的增加,且更难控制交通流量和交通条件,导致安全性降低。这些不利通常可能因为未对现有隧道运营状况、隧道真实特征、设备和环境条件进行充分分析所致,或未根据交通情况进行有效的缓解策略或措施所致。
第2.8节提出了已有隧道安全诊断及升级计划的方法论。另外,第4.9节提出了隧道运营中开展工作的相关问题,这些方法有助于这些问题的解决。
读者应注意以下章节的关键内容:
物理的检查必须辅助运营过程、运营组织和养护及与安全和救护干预相关卷宗的检查,检查的这个阶段最终可能会导致建立相关干预各方的培训,从而促进整修前隧道整体初始状态的安全情况。
诊断后必须根据隧道的实际状况进行风险分析,这种分析有以下双重的目的:
应该对隧道是够能够在目前的状态下(更新前)是否继续运营进行评估,以及是否必要采取过渡性安排:限制通行仅供某种特定类型的车辆通行、加强警戒安排及干预措施的安排、附加设备等等。
从安全角度来建立一个参考来提升更新计划的定义。
诊断需要能够识别(在工作中能正常识别而不会发生晚发现的风险)是否设备可以在工作情况下进行修正、增加或今后进行升级(工艺上的可兼容性,特别是数据采集、传输,自动起作用的设施及数据传输监控(SCADA))。
更新和升级计划分为两个阶段。
1.3.2.1. 第一个阶段:项目规划进行项目规划可能源于以下的原因:
升级计划还应基于隧道的自然环境和空间范围的限制,如果优化的基建或设备的升级计划因无法满足一些限制条件而不可行。
1.3.2.2. 第二个阶段:升级计划的审核确认
升级计划的确认工作包含以下内容:
隧道的升级或改进工作并非只必须进行实际工程改造,它也可能是仅对隧道的功能、运营安排做出修改,譬如:
本阶段的工作就是将升级的计划和方案转化为技术和合同细节,并加以实施。
本阶段需要对以下工作进行详细而深入的分析:
一般来讲,隧道生命周期可以分解为以下几个主要的阶段。
这是新隧道生命周期中最重要的一个阶段,本阶段对于隧道的建设和运营成本、技术和管理风险来讲是具有决定性意义的。
这个阶段应该对隧道这个复杂的系统所有的借口进行全面集成,这个集成工作必须从隧道设计的最初期阶段就开始(见前文)。
但是实践表明,非常不幸的是,多数隧道设计不同部分的设计是独立进行且被认为是不相干的,即使这样讲很夸张,我们仍然可以注意到:
对于土木工程所关注的,最重要的即技术风险(特别是地质风险)和带来的建设成本和工期造成的影响。
隧道施工风险分析的相关要求必须在设计中予以重视,这些要求必须详细和深入,且应与业主共同分享这些要求,针对这些风险所作的决策必须明确其决策过程且应明确记载存档。
做出的决策可能有一定的风险,但是这些决策并非一定错误或并非一定禁止的,因为这种决策可能会遇到行政命令,譬如可能是和更高一级的安排有关,这个安排可能与消除所有不确定因素的调查的实施不一致。
但是承担一定风险的决策必须是经过仔细的思考,这些思考应涉及到:
承受风险的决策千万不能是由于疏忽或某一方的不称职所造成的。
与隧道运营相关的设备,读者应重点关心以下内容:
隧道寿命周期的这个阶段经常被低估或忽略,导致隧道经常在非常非常不理想的条件下竣工,或在安全方面被过度。
这个阶段包括:
本章的主要任务就是确保:
有必要从整体上来看,客观的分析日常的活动:
隧道工程的建设和运营费用是非常昂贵的,所以从工程开始就必须特别注意技术和投资优化。
所以隧道设计从开始就应该按照以下流程进行实施:
这个过程可以确保工程的优化(建设和运营费用的优化),也可以优化工程的技术和投资的风险管理的方法,以及工程的流程。
1.5.2.1. 每公里成本比率
隧道建设成本差异非常大,对于不同的隧道基本不可能给出每公里隧道单价的成本价格,因为以下因素的不同可能导致它们在成本中所占比例的变化:
根据上述上述的分析,大致可以对隧道的成本进行分析,即通常地质条件下修筑隧道的成本是其他野外条件下基础建设成本的10倍(远离城区的情况下)。
1.5.2.2. 建设成本的分解
隧道建设的成本可以分解为以下三个部分:
下面的两个表是隧道建设费用的分解表,左边的图中是无复杂情况的隧道建设费用的分解表,右边图中是存在复杂情况下隧道建设费用分解表。
图1.5.1: 施工成本分解
注释:这些图标显示了运营和维护费用的重要性,以及利用隧道第一阶段即安排优化运营和维护成本优化的必要性。
隧道的运营成本可以分解为以下三种类型的成本:
下面两图举例说明了建设成本(土建结构、运营设备、其他费用)的分解图(相同经济情况下),和总体运营费用(隧道运营始到隧道运营三十年这一阶段费用总和)。
图1.5.2: 30年期间的费用明细
注释:以上两图表明了土建结构成本的重要性,并举例说明了土建结构成本几乎倍增的后果(右图)。
本章主要针对新规定要求的更新或升级工作,主要工作涉及到紧急撤退、结构防火、安全设施、运营等诸多需要满足安全规定的条款。
当然,实际上由于已有隧道的具体特征多种多样,很难给出具体的升级的费用,且隧道交通流量、安全工作的重要性要求在不同的国家也不尽相同。
在法国,升级公路隧道工作从2000年就开始了,使现有隧道能够满足新的规定。这些工程中对于的预算的费用差别也非常大,从几千万欧元到几亿欧元不等(已经有几个更新升级工程的预算费用超过2亿欧元)。
从投资角度来看,隧道的建设和运营过程需要耗费大量的费用,但是隧道工程可以从以下角度弥补相关投资耗费:区域经济发展、交流流动性增强、舒适的交通、安全可靠的路线,同时可以保护环境。
工程投资费用的工作亦可以通过以下措施进行保障:
本手册由于篇幅所限,将不涉及具体投资模式、机理及优缺点,可是根据具体经验这里给出一些初步的、有启发意义的指导性意见。
a) 国有企业的投资
b) 由特许经营权的投资模式-隧道作为整个基建措施的一部分
这种投资上非自主经营的隧道或特许隧道(有或没有投资方的自主)是最常见的城际高速公立收费隧道。这时隧道的建设和运营成本与其他的隧道和地上基础设施共同分担。经验表明,这种城际公路按照公路进行收费的综合收费模式容易被用户所接受,只要这种基建设施能够带来足够多的优势:节约时间、可靠且值得信赖的服务、舒适和安全。
c) 由特许经营权的投资模式-单个隧道的情况
单独隧道主要包括以下两种情况:
d) 公私合营的模式及类似情况:
许多国家都制定了隧道的规定,并制定了隧道相关的设计、施工、运营、养护、安全与救援服务的规程和指南。
关于隧道安全的条款,隶属于欧盟的国家要求,泛欧公路网络中超过500m的公路隧道的安全条款应该满足Directive 2004/54/CE,该规程规定了必须实施的最低安全标准。其他更多的欧洲国家,也遵守相关的国际惯例,即《国际公路危险货物运输协议》(ADR),其中就包括了与隧道工程相关的条款。每个成员国都根据欧洲的规定,制定了对应的国内法律。甚至一些国家的国内规定增加了新的更加严格的安全规定。欧盟成员国的公路隧道安全规定应遵守Directive 2004/54/CE,规程系统规定了泛欧公路网络中超过500m的隧道工程对安全措施的最低要求。
目前,有世界道路协会、世界隧道协会地下工程运营安全分会(ITA-COSUF)、世界隧道协会地下工程分会(ITA-AITES)合作颁布了一系列的隧道运营与安全方面的规定和规程,相关文献可以在世界隧道协会地下工程运营安全分会(ITA-COSUF - Publications)的网站上找的。虽然这些规程和规范不尽详尽,但是是37个国家和三个组织建立的国际性平台。
但是迄今为止,许多国家都没有隧道及安全方面的规范和规程,这是由于这些国家内部没有隧道工程。可以给这些国家提出以下建议,建议这些国家选择一个有较长隧道管理经验和完善的规范、规程的国家进行参考,而不必在多个国家的资料进行对比选择,否则可能导致无所适从。世界道路协会总结的这些规程,以及欧洲的European directive 2004/54/CE,都逐渐被作为国际性的规范作为参考。
This chapter consists of two main subsections:
“Complex Underground Road Networks” has been the subject under consideration by the PIARC Working Group 5 throughout the course of the 2012-2015 cycle.
The working plan consists of two sections:
The terminology “Complex Underground Road Tunnels” covers the following infrastructure:
All the structures share several similar characteristics:
The objective of the case study was to identify structures of this type around the world, to summarise collected information, to analyse it and to establish a number of preliminary recommendations for owners, designers and operators.
While this collection of information is not exhaustive and the summaries do not constitute a scientific database, it nevertheless contains pertinent and interesting findings. The collection of information was limited to the countries of origin of the Working Group 5 members, wherein the working group had active correspondents available to them.
The general methodology has been the following:
At more than 600 pages, a significant volume of information was collected. Therefore a direct publication of all information has been deemed unsuitable. The working group decided to:
Twenty-seven (27) “tunnel complexes” were analysed. The list is provided in §1.7.2.5 below. Several “complexes” consist of two to four tunnels and the actual analysis reflects a total of 41 individual tunnels.
The geographic distribution of structures analysed is shown in the graph below :
Fig 1.7.1 : Distribution of tunnel complexes within the case study and detailed distribution in Europe
The European tunnels seem over-represented in the sample analysis. This stems,
Particularly, investigations in Chile (Santiago), in Australia (Melbourne and Sydney) and a second project in South Korea were unfortunately unable to be completed by the production date of the current report. They will be the subject of future updates throughout the course of the next cycle during which supplemen-tary analysis from Germany, China, Japan, Singapore and the USA will also be considered.
The key information outlined in the analysis focus on the following aspects:
As the outcome of this analysis, the working group established a number of preliminary recommendations. These recommendations will be the subject of detailed additional developments which will be published in Part B of the report at the end of the 2016-2019 cycle.
These preliminary recommendations, presented in Chapter 11 - Present Situation, Comments and Preliminary Recommendations of the report, deal with the following aspects:
Underground road networks are located mainly in urban areas, and their design (in particular their alignment) has several constraints.
Geometrical conditions which often contribute to traffic incidents, include: meandering curved alignment, insufficient visibility near the access and exit areas, insufficiently defined characteristics of merging or diverging lanes and, poorly designed exit ramp connections towards the surface road network leading to congestion in the main tunnel, etc.
It is recommended that in preparing the alignment, the following be considered:
b - Cross-section
The investigations mentioned above show that 80% of analysed tunnels prohibit the transit of vehicles that weigh over 3.5 tonnes (or 12 tonnes, in some instances). However, the tunnel design does not take into account this restriction, and does not reconsider optimisation of the lane width as well as vertical height clearance.
Investigations carried out on recent projects show that substantial savings (from 20% to 30% depending on the final design characteristics) can be obtained by choosing a reduced vertical height for tunnels that prohibit heavy vehicle usage.
It is recommended that at the earliest stage for developing tunnel projects detailed studies be undertaken to consider and analyse the “function” of the tunnel, traffic conditions (volume and nature of vehicles), as well as the financial feasibility and financing methods. This should be done in such a way as to analyse the advantages of a cross-section with reduced geometric characteristics. This may facilitate the financial optimisation of the project without reducing the level of service or affecting the safety conditions.
c - Ventilation
Underground road networks are usually subjected to large traffic volumes. Traffic congestion is frequent, and the probability of a bottleneck developing within the network is high and recurring. As a result, the ventilation system has to be developed with a detailed analysis of the risks and dangers, taking into account the existence of bottlenecks.
A “pure” longitudinal ventilation system is rarely the appropriate sole response to all the safety requirements, especially in the scenario of a fire located upstream of congested traffic. A longitudinal ventilation system will cause smoke de-stratification downstream of the incident location. This constitutes a danger for any tunnel user blocked or in slow moving downstream traffic.
The addition of smoke extraction gallery or the choice of a transverse or semi-transverse ventilation system is often vital if no other realistic or feasible safety improvement measures can be put into place, and considered as efficient.
It is also necessary to implement equipment allowing the different network branches to operate inde-pendently of each other. This will facilitate the control and the management of smoke propagation during a fire incident.
The risks associated with the traffic of dangerous goods vehicles through a tunnel with a high urban traffic density must be carefully analysed. There are no ventilation systems capable of significantly reducing the effects of a dangerous goods large fire in such traffic conditions.
d - Firefighting
The necessary timeframe for response teams to arrive on site must be subjected to a detailed analysis under normal and peak hour traffic conditions. The objective is to determine whether or not it is necessary to install first line intervention facilities and resources in proximity of the tunnel portals.
The turnover of fire brigade staff is relatively high in urban areas and their interventions in tunnels are rela-tively rare. The high rate of turnover may lead to loss of specialist skills in tunnel intervention. Thus, it is essential to implement tools which allow continuous professional education and training of the teams. A virtual 3D model of the network, associated with simulation software, can provide pertinent, user-friendly and effective tools.
e - Signage
It is fundamental to ensure clear visibility of the exit ramps and a clear legibility of signage, in order to reduce the risk of accidents where exit ramps diverge from the main carriageway.
The locations of interchanges, entry and exit ramps, as well as the concept for signage should be analysed from the conceptual of alignment studies.
f - Environment
In order to reduce atmospheric pollution, communities, stakeholders and residents often demand the installation of filtration devices for in-tunnel air before it is released into the atmosphere.
This results in a decision to install filtration equipment which is rarely rational or technical, but in ad-hoc response to public pressure. Before any decision-making on this issue, it is, however, essential to:
g – Traffic conditions – Traffic management
The connections between exit ramps and the surface network must be equipped in a way which allows supervision and management of traffic in real time. This arrangement allows traffic congestion to be reduced inside the tunnel, and an improvement of safety should tunnel incidents require quick evacuation of users.
The coordination between operators of physically connected infrastructure is in general adequate. However, it is often essential to improve this coordination by clarifying the situation and role of each operator (particularly in the event of traffic congestion and fire incident) by defining common procedures and determining priorities between the different infrastructure parts and their traffic.
Monographs have been established for each of the structures listed in the table below. They are accessible in the Multimedia Kit at the bottom of the page. The monographs of the structures highlighted in amber are in the process of being updated and will be online shortly.
Continents | Countries | Cities | Names of the tunnels complex | Appendices |
---|---|---|---|---|
Asia | China (CHN) | Changsha | Yingpan Tunnel | 1-1 |
Japan (J) | Tokyo | Chiyoda | 1-2 | |
Yamate | 1-3 | |||
South Korea (ROK) | Seoul | Shinlim-Bongchun and Shinlim-2 | 1-4 | |
Europe | Austria (A) | Vienna | Kaisermühlen | 2-1 |
Belgium (B) | Brussels | Leopold II | 2-2 | |
Belliard | 2-3 | |||
Czech Republic (CZ) | Prague | Blanka Tunnel complex (3 tunnels) | 2-4 | |
Mrazovka and Strahov | 2-5 | |||
Finland (FIN) | Helsinki | KEHU - service tunnel | 2-6 | |
France (F) | Annecy | Courier | 2-7 | |
Ile-de-France | Duplex A 86 | 2-8 | ||
Lyon | Croix-Rousse (road tunnel + multimodal tunnel) | 2-9 | ||
Paris La Défense | A14 / A86 motorway interchange | 2-10 | ||
Voie des Bâtisseurs | 2-11 | |||
Italy (I) | Valsassina | Valsassina tunnel | 2-12 | |
Monaco (MC) | Monaco | Sous le rocher tunnel (2 interconnected tunnels with “Y” form layouts) |
2-13 | |
Norway (N) | Oslo | Opera tunnel (chain of 4 tunnels) | 2-14 | |
Tromsø | 3 interconnected tunnels with roundabouts and access to parking lots |
2-15 | ||
Spain (E) | Madrid | M30 By-pass | 2-16 | |
M30 Rio | 2-17 | |||
Sweden (S) | Stockholm | Ring Road – Northern link | 2-18 | |
Ring Road – Southern link | 2-19 | |||
The Netherlands (NL) | The Hague | Sijtwendetunnel (chain of 3 tunnels) | 2-20 | |
North America | Canada / Quebec (CDN) / (QC) | Montreal | Ville-Marie and Viger tunnels | 3-1 |
USA | Boston | Boston Central Artery | 3-2 | |
Oceania | Australia (AUS) | Brisbane | M7 Clem Jones Tunnel (CLEM7) | 4-1 |
“Underground Road networks” are “complex systems”. All the recommendations presented in Chapters 1.1 to 1.5 above are applicable to them. Nevertheless, certain “subsets” and “parameters” mentioned in Chapter 1.1 present a much more significant potential impact on underground networks. The “interactions between parameters” (see § 1.1.2.2) are generally and much more extended and complex.
Several major strategic challenges presented in the above chapters, as well as their principal interactions, and the additional parameters below, must be well considered in the process of developing tunnel designs and for the construction and operation of tunnels.
This term is applicable to tunnel cross-section, vertical alignment, implementation of interchanges, access and exit ramps. In addition to the recommendations from § 1.2.1 the following elements should be considered for:
a – Land occupation
Land occupation deals with the surface occupation in open air (roads, buildings and various structures, parks and protected areas, etc.) and the volumetric occupation of the underground space (underground infrastructures such as metro, car parks, various networks, building foundations, etc.)
The interfaces between the underground and surface spaces are numerous: ventilation stacks, access and exit ramps, evacuation corridors and intermediate emergency access.
The underground and surface land occupation constraints are not always compatible with a given location and it is often necessary to decouple surface structures from those underground. This relationship can be implemented through inclined shafts or underground corridors that link any vertical shafts that are located away from the tunnel alignment.
b - Geology, geotechnical, hydrogeology
The geological, geotechnical and hydrogeological conditions have a significant impact on the horizontal and vertical alignment especially with regard to the risk of settlement, the possibility of construction underneath existing structures and any required maintained distances to existing surface or underground struc-tures, in relationship with the construction methodology considered.
These conditions can also influence the position of underground interchanges. For example, in the case of loose soil below groundwater level a localised widening of the cross section to build ramp merge and diverge areas could require construction works starting from the surface (large shafts, treatment and land consolidation works). These works require setting up temporary occupation on the surface. Under such conditions the location of underground interchanges should then also consider the type of land occupation on the surface.
c - Functionality for traffic
The functionality of the alignment mainly deals with areas where connection to the road network at the surface (or possibly with other underground structures) has to be built. The position and the design of the main tunnel portals, the access and exit ramps, as well as the location of interchanges depend on these functionalities.
The location of all these connections is also linked to the volume of traffic in the underground network, as well as its multiple entrances and exits. The connections must take into account the absorption capacity of traffic in the surface road network, adjustments to connections design in order to avoid underground traffic congestion and thus reduce accidents and significant tunnel fire incident risks.
d - Safety – rRsks of accidents
The analysis of existing networks demonstrates a concentration of accidents around areas with curved geometry, overly steep slopes and insufficient visibility around the merge and diverge areas of ramps.
All these elements must be carefully taken into account from the early stage of the design of the horizontal and vertical alignments of a new network.
e - Methods of construction – Time period
The construction methodology has a direct impact on the horizontal and vertical alignments (and vice-versa). They are also strongly guided by the geological, geotechnical and hydrogeological conditions.
The methods of construction can have an important impact on the location of the tunnel portals. In particu-lar, the use of a shield (slurry shield or earth pressure balanced) requires significant site area not only for the assembly of a tunnel-boring machine but also throughout the duration of the works (particularly for the treatment of slurry and provisional storage). A conventionally bored tunnel (when soil conditions permit it) requires fewer facilities close to the portal, and can be accommodated in a smaller site area.
The analysis for the shortening of construction timeframes can have an impact on the horizontal and vertical alignments, for example in order to make possible intermediate construction access sites.
f – Environmental conditions
During operation period of the network, the main concerns are air quality and noise impacts. These concerns have repercussions on the positioning of tunnel portals and ventilation shafts. These issues must be analysed carefully, in particular the ventilation plants as well as the additional equipment likely to reduce the environmental impact.
The position of portals, and the associated temporary work site plants, must also be analysed from an environmental aspect in terms of construction methods and timeframes. For example, a conventional method of construction will have a more significant noise impact as opposed to a TBM construction method. If the tunnel portal is situated in a noise sensitive area, works will have to be suspended during quieter night periods, leading to a prolonged construction period and consequent inflation of costs. A modification of the portal location or changes to the alignment can reduce these impacts.
In addition to the recommendations from § 1.2.2 the following elements should be considered for:
a – Nature of traffic - Function
As mentioned in § 1.7.2.4.b above, the nature of traffic is a factor that must be carefully analysed regarding their initial conditions as well as its evolution over time. Many urban underground networks prohibit heavy vehicles (more than 3.5 t or 12 t depending on different conditions), even though they were designed with standard vertical height clearance and lane width characteristics (defined for the allowance of all types of vehicles).
Analysis of the “function” of the underground network and the evolution of that function is essential. It allows the cross-section to be optimised by choice of geometrical characteristics (vertical height clearance and lane width) to ensure adequacy for the present and future traffic that will use the network.
Savings made regarding construction costs are significant (from 20% to 30% depending on the chosen characteristics). Where applicable, these savings may allow a project to be financed, and thus feasible, where it may not have been with standard vertical clearances and lane width.
b - Volume of traffic
The volume of traffic is the determining factor in defining the number of lanes of the main tunnel, as well as interchange or access and exit ramps.
The volume of traffic should be taken into account when defining the length of merging and diverging lanes for entrances and exits. The risk of congestion, at the connection of exit ramps to the surface network, must also be considered, as well as the consequences that this has on the main tunnel (bottleneck queue) to determine whether or not it is necessary to design and lengthen a parallel lane upstream from the divergence point of the exit ramp from the main road.
c - Ventilation
The ventilation galleries to be installed inside the structure contribute considerably to the spatial requirement. Therefore, it is necessary to proceed to a preliminary “analysis of hazards and risks”, and an initial sizing of ventilation installations before definitively setting the characteristics of the functional cross-section. This approach is often iterative.
d – Geology - Geotechnics - Hydrogeology - Methods of construction
The geological, hydrogeological and geotechnical conditions, as well as methods of construction (which are often interlinked) have a vital impact on the shape and surface area of the cross-section. The following example illustrates this interaction.
In loose soil below groundwater level, the use of a shield will be required for the construction of the main tunnel. The main tunnel will be circular in shape. However, the cross-section will also depend on other functions:
Recommendations in section 1.2.3 are integrally applicable to “underground road networks”. The analysis approach must, nevertheless, take into account the complexity of underground networks and the aggravating influence of certain factors, in particular:
a - Traffic
The volume of traffic is generally more significant and in high traffic volume conditions traffic congestion is much more frequent. It follows that the number of persons in tunnel is much higher and in the event of an incident, the number of users to evacuate will be more significant.
Ramps merge and diverge areas are important locations in terms of risk of accidents.
The assumption, which is sometimes prevalent from the start of projects, that there will never be a traffic blockage must be analysed with much circumspection. It is indeed possible to regulate the volume of traffic entering into an underground network in order to eliminate all risk of bottlenecks. Nevertheless, this leads to a significant decrease in the capacity of the infrastructure (in terms of traffic volume) which often goes against the reasoning that justifies its construction. Over time, measures of reducing entering traffic must be relaxed, or even abandoned because of the need to increase traffic capacity. The probability and recurrence of bottlenecks increase, disregarding the initial assumption upon which the network was based (particularly in terms of safety and ventilation during incidents).
b - Emergency evacuation – emergency access
The analysis must take into account:
c - Ventilation
The concept and design of ventilation systems must take into account:
d – Communication with users
Communication with tunnel users must be reinforced and adapted throughout the multitude of branches within the network. Communication must be able to be differentiated between the different branches according to operational needs, especially in the case of fires.
Users must be able to identify their position inside the network, which would require, for example, the installation of specific signs, colour codes, etc.
Directional signs and prior information signs at interchanges or ramps must be subjected to careful consideration, particularly the visibility distances with regards to signals and the clear legibility of the signage.
e – Operational needs
Specific operational needs (cf. § 1.2.3.6) must be adapted to the complexity of a network, to the volume of traffic and to the resulting increased difficulties of achieving interventions under traffic conditions.
Recommendations in section 1.2.4 are also applicable to “underground road networks”. Nevertheless, anal-yses must take into account the complexities of underground road networks and the supplementary needs or conditions mentioned in Chapter 1.7.3.
The interfaces between operators of associated or related network must be subjected to a specific analysis, particularly for all aspects concerning, on the one hand, traffic management and, on the other hand, safety (especially fire incidents), including evacuation of users and intervention of emergency response agencies in response to fire incidents.
Control centres must take account of the interfaces within the network and between diverse operators. They must allow the transmission of common information which is essential to each operator, and facilitate the possible temporary hierarchy of one control centre over another. The architectural design of the network of control centres, and of their performance and methods, must be subjected to an overall analysis of organisa-tions, responsibilities, challenges and risks. This analysis should reflect a range of operational conditions such as during normal and emergency scenarios, and should review the interaction between the different subsections of the network and the respective responsibilities of each control centre.