營建社會成本量化分析模式

營建社會成本是專案的外部成本，其主要承受者並非參與專案的業主、設計顧問或承包商，而是屬於專案第三者的社會大眾。工程施做階段對於周遭環境之負面衝擊甚大，包含工地鄰近區域交通之衝擊、環境之污染及商家之營業損失等，造成人民福社之損失甚大。此外，對於公共工程之主管單位而官，社會成本分析對於規劃設計階段之方案評估、發包階段之最有利決標決選，乃至施工階段趕工策略之研提至為重要。因此，建立一個客觀的社會成本量化分析模式是當務之急。本文旨在建立一道路工程營建社會成本之量化分析模式，簡稱為「COSCO模式」。此一模式將道路工程所造成之主要社會成本歸納為三大類：(1)交通衝擊成本；(2)環境衝擊成本；以及(3)商業衝擊成本。其他如心理、視覺、美觀等層面之社會成本，由於量化之困難而加以忽略，所以COSCO屬於保守端之估算模式，實際營建社會成本應高於本模式之估算結果。經案例分析發現，道路工程施工所造成之營建社會成本平均可達專案工程費之5.27倍，可見其嚴重性。本文所提出之COSCO模式，可作為公共工程主管單位進行最佳施工規劃、研擬決標模式甚至訂定趕工獎金之參考。

關鍵字

營建工程；社會成本；量化分析；道路工程

並列摘要

Construction social costs are external costs of a construction project. They are not undertaken by the project participants-the owner, the A/E, or the contractor-but rather by the public. The negative impacts of construction works to the neighborhood consist of transportation impacts, environmental pollutions, business losses, and other effects. From the viewpoints of a public project manager, the quantitative analysis of construction social costs is also desired for alternative selection, most advantageous bid evaluation, and schedule compression strategy planning. This paper proposes a quantitative analysis model for the construction social costs called Construction Social Cost (COSCO) model. The COSCO model for roadwork projects consists of three major categories of construction social costs: (1) the transportation impact costs; (2) the environmental impact costs; and (3) the business impact costs. The other aspects such as psychological, visual, and aesthetic impacts were excluded due to the difficulty of quantification. Thus, the proposed COSCO model is a conservative model. The actual social costs shall be greater than those estimated by COSCO. According to the case study, the overall construction social costs can be as high as 5.27 times of construction cost. The proposed COSCO model provides the public project managers a tool for optimal project planning, most advantageous bid awarding, and schedule compressing incentive determination.