本研究分析在不同的道路維護計畫下，路面粗糙度與能量消耗、溫室氣體排放等環境衝擊之關係；評估結果可協助量化道路維護的環境影響。由於汽車使用階段為主要的影響，本評估亦考慮道路情況對汽車汽油消耗等因素，期能結合路面粗糙度與汽車使用成本，提供相關單位及道路使用人更全面的分析情報。
本研究建構兩個分析模式：第一，生命週期評估模式，以量化不同維護計畫所造成之能量消耗與溫室氣體排放；第二，粗糙度預測模式，以模擬道路在高降雨量及高溫情形之變化。結合以上二模式之結果與其他輔助資料，如：維護效果、情境分析及汽車使用情形等，維護計畫得以有效設計。此維護計畫之評估以40年為分析基準。
評估薄瀝青鋪面（thin hot-mixed asphalt overlay）及微表面處理（micro-surfacing）技術的結果顯示，前者因準備與實行階段需較多的材料、能源及運輸，導致更高的能源消耗與溫室氣體排放。分析結果也顯示，此二技術的材料生產過程皆為能量消耗及溫室氣體排放之大宗，約佔總過程之90%。
氣候對道路的影響是，降雨量會提升道路粗糙度，溫度則降低之。因此，降雨量大之地區需較頻繁之維護。由於微表面處理技術的使用標準受限於良好的道路狀況，該條件卻不適用於薄瀝青鋪面，因此薄瀝青鋪面技術相較於微表面處理，可減低維護頻率。雖然微表面處理技術的維護較頻繁，但是相較於目前的維護作法，仍減少了47% 的溫室氣體排放。另外，微表面處理之汽車燃料情境分析結果顯示，其較排放低之溫室氣體，故微表面處理在高雨量、高溫地區，被視作良好的維護計畫。然而，微表面處理理應在道路情形良好的時候進行，才能拉長維修之間隔期間，以減少頻繁維修所延伸之困擾。

This research evaluates several maintenance strategies that were set to relate pavement roughness condition to environmental impact in term of energy consumption and greenhouse gas (GHG) emission associated to each strategy. There are interactions present between pavement and vehicle during their use phase. Therefore, evaluation was done to quantify not only the impacts from pavement maintenance activities (from material production to construction), but also the influence of pavement condition to vehicle operation, namely the differences caused in fuel consumption of passenger cars. Here, the incorporation of roughness impact to vehicle operating cost aims to provide a complete picture of maintenance activities impact to road-related agency, road users, and to our environment.
Two models are developed and used in this study: (1) Lifecycle assessment model, to quantify GHG emission and energy consumption of each treatment technology and maintenance strategy, and (2) Roughness-prediction model, to simulate pavement condition that is posed to high precipitation and temperature over its age. The results from the both models and other data such as treatment effect, scenario setting, and vehicle use related information becoming input in designing maintenance strategies. Then, maintenance strategies were evaluated based on analysis life of 40 years.
The results show that between the two technologies evaluated, namely thin hot-mixed asphalt overlay (OL) and micro-surfacing (MS), the former needed more energy and so released more emission compare to the latter due to more material and energy (and thus transportation) required in preparing and performing the treatment. Even so, both technologies agree that material production stage is the hotspot of energy consumption and GHG emission, which accounted for around 90% of overall process.
Regression analysis implies that precipitation contributes in higher pavement roughness while, surprisingly, temperature indicates negative correlation to roughness progression. The negative correlation between temperature and roughness is not clearly understood except from the perspective of reducing wet weather damage or reduce shrink-swell of soils from being wet more of the time. Thus, more frequent maintenances are especially required for road posed to higher precipitation in Taiwan.
Furthermore, application of OL within maintenance strategies resulted in fewer maintenance cycles compare to MS employment. It is because MS requires a relatively good road condition in order to suffice the expectation of the treatment while that requirement not really applied to OL so that OL application can be delayed a bit. Despite of the number of MS cycles is greater, it still give a lower emission accumulation up to 47% compare to current practice. The associated vehicle fuel consumption for MS-related scenario also show a lower emission accumulation, thus MS can be considered a good maintenance approach to be applied in region with intense precipitation and temperature. However, MS should be done when the road condition is good which will be better to be applied in a road with low-initial pavement roughness, so that the intermittent period between each treatment cycles is longer and road user do not suffer from undesired number of frequent maintenance.

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