Microtunnelling: Optimising Low-Emission Construction of Buried Utility Infrastructure (MOLE)

建筑和建设占全球碳排放总量的39%。从现在到2050年，在建成资产使用之前释放的碳排放，即“隐含碳”（EC），将占新建筑总碳足迹的一半以上。2010年，仅英国就需要大量新的地下基础设施。因此，可持续建筑技术的发展至关重要。本项目侧重于新型低碳微隧道（MT）的开发、测试、优化和验证。MT是一种日益流行的非开挖、遥控施工方法，用于提供地下公用隧道和管道，通常直径为0.5 m至4 m[2]。因此，该项目属于EPSRC基础设施研究领域。传统上，开放式施工（从地面挖沟，管道铺设在沟内）已被使用。与露天施工相比，非开挖施工技术已被证明可减少高达84%的碳排放。然而，与非开挖施工相关的EC仍然高得令人无法接受（每公里约22吨二氧化碳）。现有的研究涉及替代非开挖技术，而不是MT。这种研究的缺乏阻碍了基于环境影响的优化，而不仅仅是项目成本，因此迫切需要量化和跟踪与英国MT相关的EC。该研究旨在为下一代使用低碳材料和MT操作的关键埋地基础设施提供基础工程科学。具体而言，该项目将直接解决以下障碍，以实现地下基础设施的脱碳交付：a)与MT的不同施工阶段和活动相关的EC的不确定性，b)过时且过于保守的设计指南，以及c)普遍接受的高EC钢筋混凝土管道设计。为了实现这些目标，将实现以下可衡量的目标：(1)执行EC LCA以建立与MT相关的当前基线EC水平。LCA将允许对与不同MT建设阶段和运营相关的EC进行定量评估，以提供前所未有的高碳活动洞察力。这是新颖的，因为现有的文献都集中在替代非开挖技术。(2)通过开发现场部署的新型测量技术，开发一个框架，智能准确地推断MT顶管的加载历史。(3)开发并实验测试新型低碳MT管道，设计出能够安全承受测量载荷历史的管道。建立并验证MT管道的新设计方法。(4)与Tracey Concrete、Ward和Burke construction合作，在现场施工现场开发、测量和部署一种新型概念仪表智能管道，以进一步测试、验证和优化新的MT设计指南的开发。(5)通过减碳措施评估项目的成功程度。参考资料：[1]全球现状报告（2017），联合国环境署。& Int。能源机构。[10] Phillips， B.M.等（2019）doi: 10.1680/icsic.64669.457。bbb10国家基础设施委员会（2017），拥堵、容量、碳：国家基础设施的优先事项。[10] Tavakoli， R.等。（2017）doi: 10.1061/ 9780784480892.005。[10] Nandyala， V.K.等（2019）doi: 10.1061/9780784482506.007。

Building and construction are responsible for 39% of all carbon emissions in the world [1]. Carbon emissions released before the built asset is used, referred to as 'embodied carbon' (EC), will be responsible for more than half of the entire carbon footprint of new construction between now and 2050. A substantial amount of new buried infrastructure is required in the UK alone [3]. As such, the development of sustainable construction techniques is essential. This project focuses on the development, testing, optimization, and validation of novel low carbon microtunneling (MT). MT is an increasingly popular trenchless, remote-controlled construction method for the provision of underground utility tunnels and pipelines typically 0.5 m to 4 m in diameter [2]. As such, this project falls within the EPSRC Infrastructure Research Area. Traditionally, open-cut construction (where a trench is dug from the ground surface and the pipeline is laid within the trench), has been used. Trenchless construction techniques have been shown to deliver up to 84% reduction in carbon emissions compared to open-cut construction [4]. However, the EC associated with trenchless construction remains unacceptably high (~22 tonnes of CO2 per km [5]). Existing research relates to alternative trenchless technologies rather than MT. This lack of research inhibits optimisation based on environmental impact, rather than solely on project cost, so there is an urgent need to quantify and track the EC associated with UK MT. The research will aim to deliver the underpinning engineering science for next generation critical buried infrastructure using low-carbon materials and MT operations. Specifically, this project will directly tackle the following obstacles towards decarbonising the delivery of buried infrastructure: a) uncertainty surrounding the EC associated with the different construction stages and activities for MT, b) out-dated and overly conservative design guidelines, and c) commonly accepted high-EC reinforced concrete pipe designs. To realise these aims, the following measurable objectives will be achieved: (1) Perform an EC LCA to establish current baseline EC levels associated with MT. LCA will allow a quantitative assessment of the EC associated with different MT construction stages and operations to provide unprecedented insight into high-carbon activities. This is novel as existing literature has focused on alternative trenchless techniques. (2) Develop a framework to infer the loading history of MT jacking pipes intelligently and accurately by developing novel measurement techniques deployed on site. (3) Develop and experimentally test novel low-carbon MT pipes designed to safely withstand the measured load histories. Establish and validate new design methodologies for MT pipes. (4) Develop, instrument, and deploy a novel conceptual instrumented smart pipe on live construction sites, working with collaborators Tracey Concrete and Ward and Burke Construction, to further test, validate and optimize the development of new MT design guidelines. (5) Evaluate the success of the project through carbon saving measurements. References: [1] Global Status Report (2017), UN Environ. & Int. Energy Agency. [2] Phillips, B.M. et al. (2019) doi: 10.1680/icsic.64669.457. [3] National Infrastructure Commission (2017), Congestion, Capacity, Carbon: Priorities for national infrastructure. [4] Tavakoli, R. et al. (2017) doi: 10.1061/ 9780784480892.005. [5] Nandyala, V.K. et al. (2019) doi: 10.1061/9780784482506.007.