營建承包商精實分包採購流程之改善方法

An Improved Approach to the Lean Subcontracting Procurement Process (LSPP) for Construction Contractor with Cases

吳青龍(Ngo Thanh Long)

指導教授 ： 曾惠斌

共同指導教授 ： 謝尚賢 ； 荷世平(Ho, Shih-Ping)

國立臺灣大學/工學院/土木工程學研究所/博士(2012年)

https://doi.org/10.6342/NTU.2012.03260

摘要

對於承包商和業主而言，瞭解並減少營建專案浪費是極為重要的課題。營造業的浪費情況，一直是政府、業主、承包商等社會各界關注的問題。浪費不僅減少營建專案各方參與人的利益，同時也會造成環境污染。此外，若干研究報告亦指出，營造業的浪費情況較其他產業來得嚴重。然而，先前的研究大都集中在如何消除單一種類的浪費，並未提出消除營建專案多種主要浪費的方法。
分包採購的先期規劃，是營建專案管理的主要任務，可讓承包商以較低成本取得工程案件，但卻不因此犧牲工程品質、時間和安全等其他標準。不僅如此，分包採購的先期規劃，可以建立控制系統的標竿，俾利追蹤工程品質、成本與時間，減輕承包商的工程執行與管理負擔。傳統的規劃模型往往只建立在生產的轉換（任務）概念之上，假設任務就是生產過程，而忽視了生產的工作流程與價值創造概念。然而，工作流程概念是營建專案規劃非常重要的因素，因為它可以解決工作流程中絕大多數的浪費。然而，現今關於規劃模型的研究非常有限，大多數研究都集中在規劃的工具和技術，而非規劃程序。此外，有關規劃的研究也大多涉及環境、交通、業主規劃程序、工程範圍界定及水資源規劃，承包商往往不關心營建專案的先期規劃，因此，營建專案往往存在許多規劃的問題，包括時間的浪費、遲延和溝通不良等等。
分包採購程序尤其影響工程專案與營建專案的成本。傳統的分包採購程序往往會限制價格談判機會以及承辦商之間的合作，並且忽略許多潛在的問題，例如工程界面、營建風險和浪費。傳統上，分包採購幾乎都是透過價格談判和價格競爭來降低工程成本。此方法旨在降低人工、機器、設備和物料成本，同時維持一定的工程品質，並滿足業主對於工程施工的要求。然而，此種採購方法主要有四大缺點：(1)浪費時間、物料、機械、人力等，這些浪費會隨著工程進度，一一反應在專案成本上；(2)限制價格談判的機會；(3)在價格談判過程，往往忽略工程界面、營建風險等潛在的問題；(4)承包商彼此競爭，充滿敵意，導致無法促進創新。儘管研究分包採購的文獻不少，但這些研究大都著重於如何遴選分包商、分包商遴選標準、分包商評分技巧，以及如何利用網際網路和人工智慧來遴選或評估分包商。這些研究並未說明分包商在採購與營建過程，如何消除浪費、預測風險，並且與其他承包商建立良好的合作關係。
本研究首先點出營建專案的七大類浪費，並應用製造業的精實理論，提出三大方法，有效消除營建專案的浪費情況。其次，本研究針對承包商，提出「精實規劃模型」(LPM)。LPM可大幅消除營建專案的主要浪費，因為此模型有效結合生產的三個重要概念：轉換(T)、流程(F)和價值創造(V)。LPM模型包含七個準備步驟，本研究將提供系統性的說明，以協助承包商實際應用於營建專案。LPM的方法係基於TFV三個概念的整合。第三，本研究根據營建專案的案例研究，以精實營建理論為基礎，提出「精實分包採購程序」(LSPP)。該模型包含一個全新的七大安排 (Seven-Arrangement)執行計畫，以及四種標準作業流程。 LSPP不僅僅可以協助分包商消除營建專案的各種浪費，同時也能建立一個公共的訊息平台與合作環境，協助承辦商逐一瞭解各個作業程序，進而了解整個工程專案。如此一來，參與承包商便可建立合作關係，潛在的風險可以早期發現，承包商之間也可以共享利潤。因此，LSPP程序可讓承包商獲得長遠利益，並且更有效地消除浪費情況。

關鍵字

精實分包採購程序 ； 精實規劃模型 ； 七大浪費 ； 專案成本

並列摘要

Realizing and reducing types of waste in construction projects are very important to both construction contractors and owners. Waste in the construction industry is an interested problem that has been cared by all society such as government, owner, construction contractor, and so on. Waste not only reduces benefit of all participants in construction projects, but it also causes environmental pollution. In addition, some studies have concluded that waste level in the construction industry is relatively high. However, most previous studies have focused on ways to eliminate individual types of waste, and they have not proposed a method to eliminate main types of waste in construction projects.
Early planning in the subcontracting procurement is an essential function of construction project management, and it allows construction contractors to obtain projects with low cost while achieving other criteria, such as quality, time, and safety. Early planning in the subcontracting procurement also helps contractors during the whole project execution and management since it establishes the benchmark for the control system to track the quality, cost and time of project. The traditional planning model often bases on only the transformation (task) concept of production under the assumption, which considers the task, is a production process, while flow (workflow) and value generation concepts are often ignored. In contrast, the workflow concept is an important contributor for planning the construction project because it addresses the high levels of waste in the workflow. However, there is limited research regarding planning model; most research has focused on planning tools and techniques as opposed to the planning process. Moreover, most of the research on planning relates to the environment, transportation, the owner planning process, scope definition, and water planning. Construction contractors tend to not be concerned with the early plan. As a result, many problems relating to planning, including wasted time, delays, and poor communication, exist in construction projects.
The subcontracting procurement process is one of the most important issues impacting the costs of engineering projects and construction projects, in particular. Traditional procedures of subcontracting procurement tend to limit the opportunities for price negotiation and cooperative relationships between contractors and neglect potential issues such as engineering interface, construction risk, and waste. Traditionally, the subcontracting procurement almost always uses price negotiation and price competition in order to lower the price of the project. This method aims to reduce labor, machine, equipment, and material costs while maintaining quality and meeting the project owner’s requirements. However, this procurement method has four main weaknesses: (1) wastage such as time, material, machine, manpower, etc., which can accumulate and prove costly for a project; (2) this procurement limits the opportunities for price negotiation; (3) potential issues with the engineering interface and construction risks are often neglected during price negotiation; (4) relationships between contractors are competitive and adversarial, and it has not promoted innovation. Despite the many studies on the procurement of subcontractors, the focus of these studies has been limited to the selection of a subcontractor, subcontractor selection criteria, subcontractor rating techniques, and use of internet and artificial intelligent in selecting or evaluating subcontractor. Moreover, these studies do not address how a subcontractor might eliminate waste, predict risk, and achieve cooperative relationships with other contractors during the procurement and construction processes.
Firstly, this research identified seven major types of waste in construction projects, and it applied the manufacturing industry’s lean theory to propose three important methods that can effectively eliminate types of waste in the construction projects. Secondly, the research proposed a lean planning model (LPM) for construction contractors. The LPM can significantly eliminate the main types of waste in construction projects because it effectively combines three important concepts of production: transformation (T), flow (F), and value generation (V). This model includes seven arrangement steps, which are described systematically to help contractors with real-world applications. The method of LPM is based on an integration of TFV concepts. Thirdly, based on case studies of construction projects, the research proposed a lean subcontracting procurement process (LSPP) drawing from lean construction theory. The model consists of a novel Seven-Arrangement operation plan and four types of standard operating flows. Not only does the proposed LSPP help subcontractors eliminate various types of waste in construction projects, it also establishes a common information platform and cooperative environment that help participating contractors understand the work emphasis of each operation and the whole operation in sequence. As a result, the relationships between participating contractors become cooperative, potential risks in construction projects can be discovered early, and profits are shared between contractors. Thus, this process allows contractors to obtain long-term benefits and improved elimination of waste.

並列關鍵字

Lean subcontracting procurement process ； Lean planning model ； Seven types of waste ； Project cost

參考文獻

Menches, C. L., Hanna, A. S., and Russell, J. S. (2005). “Effect of Pre-Construction Planning on Project Outcomes.” Proceedings of the Construction Research Congress, San Diego, California, United States.

Ibbs, W., Nguyen, L.D., and Simonian, L. (2011). “Concurrent Delays and Apportionment of Damages.” Journal of Construction Engineering and Management, 137(2), 119–126.

Lee, T. C., Lee, T. H., and Wang, C. H. (2009). “Decision Analysis for Construction Contract Risk-Sharing.” Journal of Marine Science and Technology, 17(2), 75–87.

Cheung, S. O., Ng, T. S. T., Wong, S. P., and Suen, H. C. H. (2003). Behavioral Aspects in Construction Partnering.” International Journal of Project Management, 21(5), 333–343.

Abdelgawad, M., and Fayek, A. R. (2010). “Risk Management in the Construction Industry Using Combined Fuzzy FMEA and Fuzzy AHP.” Journal of Construction Engineering and Management, 136 (9), 1028-1036.