Climatic effects and road subgrade stabilization

气候影响和路基稳定

• 批准号: RGPIN-2019-04593
• 负责人: Siddiqua, Sumi
• 金额: $ 3.13万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=761777
• 关键词: Climatic; effects; road; subgrade; stabilization

Studying and validating novel techniques for road subgrade stabilization is becoming an increasingly important field, especially considering extreme climatic effects that may take a toll on road infrastructure. At the same time, initiatives such as Canada's Climate Lens encourages infrastructure projects to maintain a focus on reducing greenhouse gas emissions. The proposed research addresses these issues, while aiming to develop a novel calcium bentontite-based chemical additive for road subgrade stabilization that minimizes, or sequesters, carbon emissions, and remains resilient to the effects of climate change. Two important parameters, the resilient modulus (MR), and the soil suction (s), play a key role in contributing to the stiffness and strength of soils. Ideally, chemical additives, such as a proposed optimum ratio of an alkaline activator and magnesium chloride (MgCl2), lead to higher soil stiffness. Climate change, however, results in a gradual loss of this stiffness. Consequently, the resilient modulus and soil suction parameters must be studied at various temperatures and curing periods to study the strength of subgrade soils, and to predict the climatic influence on stiffness. These behaviours will be studied through a series of spectroscopic and microscopic tests; including: X-ray diffraction (XRD), Energy Dispersive Spectroscopy (EDS), a field emission scanning electron microscope (FESEM), and Fourier transform infrared spectroscopy (FTIR). Additionally, a CO2 sequestration technique of the proposed binders will be studied by carbonating two binders: (i) alkaline activated MgCl2 and (ii) Ca-bentonite alkaline activated MgCl2. The mechanical and microstructural properties of these carbonated binder-stabilized soils will be analyzed through spectroscopic and microscopic tests. The research outcomes of the chemical stabilization technologies will support road construction with materials that have reduced carbon emissions and energy consumption. Moreover, this research will save millions of dollars in long-term public infrastructure projects by developing a greater knowledge of stiffness properties of subgrades under the influence of climate change. Trained HQP exposed to this research will become highly skilled leaders and engineers supporting Canadian innovation in road construction technology.

研究和验证道路路基稳定的新技术正成为一个日益重要的领域，特别是考虑到可能对道路基础设施造成影响的极端气候效应。与此同时，加拿大的气候透镜等倡议鼓励基础设施项目保持对减少温室气体排放的关注。拟议的研究旨在解决这些问题，同时旨在开发一种用于道路路基稳定的新型钙基膨润土基化学添加剂，该添加剂可最大限度地减少或封存碳排放，并保持对气候变化影响的弹性。回弹模数(MR)和土壤吸力(S)这两个重要参数对土的硬度和强度起着关键作用。理想情况下，化学添加剂，如建议的碱性激活剂和氯化镁(氯化镁)的最佳比例，会导致更高的土壤硬度。然而，气候变化导致这种僵硬逐渐消失。因此，必须研究不同温度和养护时间下的回弹模数和土体吸力参数，以研究路基土体的强度，并预测气候对刚度的影响。这些行为将通过一系列光谱和微观测试来研究；包括：X射线衍射(XRD)、能量色散光谱(EDS)、场发射扫描电子显微镜(FESEM)和傅立叶变换红外光谱(FTIR)。此外，将通过碳化两种粘结剂来研究所提议的粘结剂的二氧化碳固定技术：(I)碱活性氯化镁和(Ii)钙基膨润土碱活性氯化镁。这些碳化结合料稳定土的力学和微结构特性将通过光谱分析和微观测试进行分析。化学稳定技术的研究成果将支持使用减少碳排放和能源消耗的材料进行道路建设。此外，这项研究将通过更多地了解路基在气候变化影响下的刚性特性，在长期公共基础设施项目中节省数百万美元。接受过这项研究的训练有素的HQP将成为支持加拿大道路建设技术创新的高技能领导者和工程师。