時程管理是營建專案於專案生命週期不同階段皆非常重視的工作。國內工程專案多採用要徑法進行工期推估,但此方法在專案執行中的控制功能仍然有可改善之空間。因此,本研究以國外相關研究為基礎,以實獲值管(Earned Value Management)方法做為研究主軸。實獲值管理已發展多年,多被應用於掌控專案各階段之工期,並被學者證實預警能力良好。近年來,有關實獲值管理的相關方法被大量延伸,學者們針對所有方法進行整理及比較,發現實獲時程方法(Earned Schedule Method)在工期推估中的表現良好,儘管它仍有部分使用限制。為解決過去研究指出存在的問題,本研究整理實獲時程方法的使用限制,接著設計模擬案例找出除了方法的選用外,是否還有其他可能之因子亦會對工期推估造成影響,提供使用者可遵循的規則。最後,基於上述模擬結果,本研究提出使用原始實獲時程方法之插值法概念,改善先前研究已建立之實獲時程方法(Earned Schedule Min)在工期推估上無法即時發現非要徑上作業延遲之情境,並進一步統整模擬成果,提出使用限制更少、應用範圍更廣之工期推估方法供使用者參考。經由測試分析確認,本研究提出的方法在工期推估的準確性良好,能夠做為未來專案時程管理工期推估的方法之一。;
Schedule management is a process in which construction projects attach great importance to different stages of a project lifecycle. In Taiwan, the critical path method (CPM) is generally utilized in a project to estimate the duration thereof, but this method is subject to some unsolved restrictions. Thus, some researchers have proposed the earned value management (EVM) method to control the duration of aproject in each stage, and have proven that EVM has a good warning ability of time overrun by forecasting. In recent years, there have been many relative extensions
concerning the index of duration forecasting, and some researchers have compared all methods to find the most accurate one, which is earned schedule management (ESM).
According to the aforementioned, this research will tidy up the restrictions of ESM and then use a simulated project to search for the factors which may affect the accuracy of the ESM-based approach and provide a working rule to users for
reference. Based on the aforementioned simulated results, we use interpolation which is applied in ESM calculation to improve how the existing method’s earned schedule min. (ESmin) cannot find delay instantly while activity is on a non-critical path. Finally, we look forward and promote project managers applying the improved ESM-based approach to enhance the accuracy of duration forecasting in a construction project.