長期施工期間改道流量預測模式之構建與應用探討－－以國道3號田寮路段為例

Construction of Route-diversion Traffic Flow Prediction Model and Its Potential Applications to Long-term Roadwork: A Case Study in the Tianliao Segment of No.3 Freeway

本研究係透過反S-Curve模式之構建，以進行高快速路網中路段施工期間，施工路段每日流量變化預測。有別於以往傳統運輸規劃之靜態交通指派僅能獲得路段之均衡流量，且無須利用複雜的逐日學習與適應性的旅運決策行為理論，便可將施工期間每日流量變化之預測以簡易且正確的方式進行。本研究利用高速公路管理局提供之實際長期施工路段流量資料，經由資料篩選、轉換與嚴謹的統計檢定過程，完成該案例施工路段數種型態之改道流量預測模式構建，並經由相關統計評估指標評比得出以羅吉斯特函數為基礎之反S-Curve為最佳模式。最後以該模式進行多種實際應用之探討，並依據模式之特性提出一個全新的「衝擊損失」指標，以作為相關施工計畫評選參考之依據。

This study proposes a predictive model for the daily traffic volume changes of a freeway/expressway section during roadwork periods. Data collected from Taiwan Area National Freeway Bureau (TANFB) were used to illustrate the capability of using the proposed model on roadwork planning evaluation. Unlike the conventional static transportation planning models, which only can obtain one set of equilibrium traffic volume of the roadwork links, this model can be easily used to predict traffic volume during roadwork periods without the need for day-to-day learning or complex traffic decision-making theory with adaptiνe behaviors. The data for this study were long-term actual traffic volume collected from vehicle detectors along roadwork links. After the data were selected and transformed, a reverse-S-Curve based on logistic function was applied to the development and evaluation of the model. With several models being evaluated under various criteria, the logistic model in the form of reverse S-Curve has proven to perform the best. This model can be used for the prediction of gradually decreasing daily traffic flows towards another equilibrium level through the roadwork section under long-term maintenance work in freeway/expressway networks. Finally, the model was used in the discussion of various potential applications. Based on the developed model's characteristics, "impact loss" was adopted as an evaluation criterion in roadwork plans.