專案管理與系統思考在施工計畫問題解決之應用-以河川環境營造工程管理為例

Abstract

專案係指一個獨特而有時間及預算限度的任務，河川環境營造工程亦需在一定的時間和預算內，達成預定的河川環境營造任務，具備一般專案的特性，也符合專案管理的「起始」、「規劃」、「執行」、「監督與控制」及「結束」等專案生命週期。但實務上在工程執行過程中常常發生趕工、加班、變更設計等狀況，若能從根本上找出問題的原因，並提出治本的方法，將能有效提升河川環境營造工程之品質。有鑑於此，本研究目的在藉由問卷調查了解河川環境營造工程管理在實務上所發生之問題，並運用系統思考分析規劃流程上之差異對執行過程影響之因果回饋關係，再據以提出根本上的改善建議。本研究首先藉由分析工程實務與專案管理知識體系兩者間規劃流程上之差異而設計問卷，再以深度訪談的方式來了解及確認問題所在，最後經由因果關係及系統回饋圖分析規劃流程上的差異與實務上執行過程所發生的問題間之關聯性，並據以提出規劃流程之短、中、長期改善策略。 本研究發現實務上執行監控之問題的根本原因，乃是其工作項目之分類與專案管理所強調之工作分解結構不同，因此從專案管理的角度而言，難以定義出明確的階段性交付標的，因此即使實務上亦以工程之實獲值控管工程進度，仍容易造成施工進度落後。另外，專案管理上之成本乃是時程規劃後的成果，惟在工程實務上，合約成本的限制卻在工程施作的時程規劃之前，因此容易產生因投標時估價不足而產生虧本。。除此之外，缺乏完整的風險規劃增加專案額外成本進而影響利潤。本研究建議短期改善策略需在施工計畫書規劃過程中加入資源行事曆，以及風險計畫書改善資源調度問題以及額外的專案成本﹔中期改善策略有二，(一)為改善招標文件以工作分解結構作為工作項目之拆解方式，以便可有明確的階段性交付標的，而方便執行過程之進度控管，(二)為於投標時先行規劃施工計畫書以及品質計畫書，已使成本估算更為精確；長期改善策略建議將完整的專案管理知識體系落實在河川環境營造工程之中，以解決橫跨多角色之專案整體管理。

A project can be referred to a mission with restrictions of time and budget. The task of environmental rehabilitation and planning shares the common characteristics and the same life cycle with a "project." The life cycle includes processes of the start, planning, execution, monitoring and control, and the end. In practice, the problems of makeup works, overtimes, and design changes are common. If the causes of these problems can be found and solved, the quality of the task of environmental rehabilitation and planning can be improved. Therefore, this study uses questionnaires to investigate the problems occurred in practice and uses in-depth interview to identify the problems. To analyze these problems, a systematic method is used to evaluate the relationship between the difference of planning process and the results using Cause-and-Effect diagram. Based on this analysis, short, medium, and long term improvement strategies are provided. The result shows that the task category in practice and the work breakdown structure are defined differently, which is the main reason to cause the problem of monitoring. In other words, the deliverable for each phase is not easy to be clearly defined. This poor definition could result in delay even, in practice, the schedule is usually controlled by the earned value. Besides, the cost of the management project is the result of time planning. However, in practice, the restriction of the contract cost is prior to the time planning. This priority could cause underestimation of the cost and result in economic loss. In addition, lack of complete risk assessment could increase additional cost of a project and reduce the profit. The short term strategy is that the resource calendar and risk assessment should be added into construction plan to properly allocate the resource and reduce additional project cost. Two median term strategies are provided. First, clearly defined deliverables should be provided using work breakdown structure for better monitoring results. Second, The construction plan and the quality plan should be prepared prior to the bidding. Then the cost estimation could have better accuracy. The long term strategy is that the complete knowledge of project management should be applied to the entire process of the task of environmental rehabilitation and planning. This knowledge can improve the quality of project management.