EPC (Engineering Procurement Construction) model, also known as design, procurement, construction integration mode. It means that after the project decision-making stage, from the beginning of the design, a tender is entrusted to an engineering company to perform general contracting for design-purchase-build. Under this model, according to the total price or adjustable total price stipulated in the contract, the engineering company is responsible for managing and controlling the progress, cost, quality, and safety of the project, and completing the project according to the contract. EPC has a variety of derivatives and combinations, such as EP+C, E+P+C, EPCm, EPCs, EPCa, etc. 1) Advantages: The owner entrusts the project's design, procurement, construction, and start-up services to the project's general contractor. The owner is only responsible for overall, principled, and objective management and control. The general contractor can better exert his subjective initiative and can use it. Its advanced management experience creates more benefits for owners and contractors themselves; it improves work efficiency and reduces the amount of coordination work; there are few design changes and the construction period is short; As a total price contract is used, there is basically no need to pay claims and additional project costs; the final price of the project and the required duration of the project have a greater degree of certainty. 2) Disadvantages: The owner can not control the whole process of the project; the general contractor is responsible for the cost period and quality of the entire project, increasing the risks of the general contractor, the general contractor to obtain more profits in order to reduce the risk, and may reduce the cost by adjusting the design plan. , may affect the quality in the long-term sense; Due to the use of a total price contract, the contractor’s flexibility to obtain the owner’s change order and additional fees is minimal. 2. Project Management Contracting (PMC) model PMC is ProjectManagementConsultant, the project management contract. Refers to the project management contractor on behalf of the owners of the project for the entire process, a full range of project management, including the overall project planning, project definition, project bidding, selection of EPC contractors, and the design, procurement, construction, trial operation Management generally does not directly participate in the specific work of the project design, procurement, construction and commissioning. The PMC model reflects the separation of the preliminary design and the construction drawing design. The construction drawing design enters into the field of technical competition, except that the preliminary design is completed by the PMC. 1) Advantages It can give full play to the management contractor’s professional skills in project management, harmonize and manage the design and construction of the project, reduce conflicts, and help save the investment in construction projects; the model can optimize the design of the project and can be implemented in the project. During the life cycle, the lowest cost is achieved; while ensuring good quality, it is beneficial for the contractor to obtain the right to the stock or return of the project in the future, and the construction period can be shortened. In high-risk areas, the company usually uses a deed to stabilize the team. . 2) Drawbacks The degree of owner involvement in the project is low, the right to change is limited, and coordination is difficult; the owner's big risk lies in the ability to choose a high-level project management company. This model is usually applied to large-scale projects with a project investment of over 100 million U.S. dollars. Projects in countries and regions that lack management experience, the introduction of PMC can ensure the successful completion of the project. At the same time, help these countries and regions to improve project management. Projects built using banks or foreign financial institutions, consortium loans or export credits. Process equipment is numerous and complex, and the owner is not familiar with these processes. 3. Design-Build (DB) Model That is, the design-build mode (DesignAndBuild) is also called Turn-Key-Operate internationally. In China, design-construction general contracting model (Design-Construction). After the principle of the project was determined, the owner selected a company responsible for the design and construction of the project. This method is based on a total price contract when bidding and entering into a contract. The design-build general contractor is responsible for the cost of the entire project. He first selects a consulting and design company for design, and then uses competitive bidding to select subcontractors. Of course, he can use the company's design and construction strength to complete part of the project. Avoid the contradiction between design and construction, can significantly reduce the cost of the project and shorten the construction period. However, the main concern of the owners is that the project is delivered and used according to the contract, and does not care how the contractor implements it. At the same time, when selecting a contractor, the merits and demerits of the design plan are taken as the main evaluation factors, which can guarantee the owner to obtain high-quality engineering projects. 1) Advantages The owner and the contractor work closely together to complete project planning and acceptance, reducing the time and cost of coordination. The contractor can incorporate knowledge, experience, material, construction methods, structure, price, and market into the design in the initial stage of the participation; Cost, lower cost. The foreign experience shows that the implementation of the DB model can reduce the cost by an average of 10%; it is conducive to schedule control and shortens the construction period; the risk responsibility is single. Generally speaking, the contract relationship of the construction project is the relationship between the owner and the contractor. The responsibility of the owner is to pay according to the contract. The responsibility of the general contractor is to provide the products required by the owner on time, and the general contractor The entire process of construction bears full responsibility. 2) Drawbacks The owners have lower ability to control the final design and details: the design of the contractor has a great influence on the economic efficiency of the project. Under the DB model, the contractor bears greater risks. The construction quality control mainly depends on the function description of the owner when tendering. Quality, and the level of the general contractor has a greater impact on the quality of the design; there is a short time, lack of specific laws and regulations, there is no special type of insurance; delivery methods are complex to operate and less competitive. 4. Parallel Delivery (DBB) mode That is, Design-Bid-Build, which is one of the earliest projects in the world and one of the earliest projects. It means that the owner commissions an architect or consulting engineer to carry out the preliminary work (such as conducting opportunity research, feasibility study, etc.), and then design after the project evaluation is approved. In the design phase, the construction bidding documents are prepared, and then the contractor is selected through bidding; while the subcontracting of individual projects and the procurement of equipment and materials are generally contracted by the contractor and subcontractors and suppliers, and organized and implemented. In the implementation phase of the project, the engineer provided construction management services for the owner. The most prominent feature of this model is that the implementation of the project must be emphasized in accordance with the order of the DBB. Only one phase can be completed before the other phase. 1) Advantages The advantages are expressed in mature management methods. All parties are familiar with the relevant procedures. Owners are free to choose consulting design personnel. They can control the design requirements. They are free to select engineers. Standard contract texts that are familiar to all parties can be used to facilitate the contract. Management, risk management and reduction of investment. 2) Drawbacks The project cycle is long, the owner and the design and construction parties sign the contract, manage the project by themselves, and the management fee is high; the designability is poor, the engineer's ability to control the project goal is not strong; it is not conducive to the division of responsibilities of the engineering accident, and disputes arise due to the drawing problem. More claims and more. This management model is the most common in the world. All projects based on World Bank, Asian Development Bank loan project and FIDIC contract conditions adopt this model. The "Project legal person responsibility system", "Tender bidding system", "Construction supervision system", and "Contract management system" commonly used in China today basically refer to this traditional model of the World Bank, ADB, and FIDIC. 5. Construction Management Contracting (CM) Model Construction Management Approach mode is also called "edge design, construction side" mode. In phased contracting mode or rapid track mode, the CM mode is entrusted by the owner to the CM unit. As a contractor, the conditional “edge design and edge construction†is adopted, focusing on shortening the project cycle, also called the fast path method. That is, FastTrack's production organization method is used for construction management, directly directing construction activities, and affecting design activities to a certain extent, and its contract with the owner usually adopts such a contracting mode of “cost + profitâ€. This way through the construction manager to coordinate the design and construction of the contradiction, so that decision-making open. It is characterized by a joint team of engineering project managers and engineers entrusted by owners and owners to jointly organize and manage the planning, design, and construction of the project. After completing a part of the sub-item (single item) engineering design, the part will be tendered and issued to a contractor. Without the general contractor, the owner will directly sign the contract with the contractor according to each individual project. This is a contract management model widely popular in foreign countries in recent years. This model is different from the continuous construction and production mode in which tenders are completed after the design drawings of the past are completed. The general method of bidding and contracting is compared with the method of stage contracting. Two forms of implementation of CM mode: CM unit service, sub-agent type and non-agent type. 1) Agency CM ("Agency" CM): Work as an agent of the owner and collect service fees. 2) Risk-type CM ("At-Risk" CM): As a general contractor, it can directly distribute packages, sign contracts directly with subcontractors, and assume the maximum project cost GMP for the owners, if the actual project costs exceed GMP. , More than part of the CM unit. 1) Advantages In terms of project schedule control, the CM model adopts decentralized contracting and centralized management to allow full overlap between design and construction, which will help shorten the construction period; The CM unit's strengthening of coordination with the designer can reduce delays caused by modifying the design; In terms of investment control, through the coordinated design, CM units can also help owners adopt rational engineering methods such as value engineering to explore the potential for saving investment and greatly reduce design changes during the construction phase. If a CM model with GMP is adopted, the CM unit will assume more direct economic responsibility for the control of the project cost, which can greatly reduce the owner's risk in project cost control; In terms of quality control, design and construction are combined and coordinated with each other. When new processes and methods are adopted on the project, it is beneficial to the improvement of construction quality; 5) The choice of subcontractors is jointly determined by the owner and the contractor, and therefore more For wise. 2) Drawbacks The requirements for the qualification and reputation of CM managers and their employers are relatively high; the subcontracting bidding may result in higher contracting fees; the CM model generally adopts a “cost plus compensation†contract, which requires a relatively high contract model. 6. Build-operate-transfer (BOT) mode: That is Build-Operate-Transfer mode. Refers to the consortium of a country's consortium or investor as a project, obtaining a concession for the construction of a project's infrastructure from a national government, and then independently establishing a project company in conjunction with other parties responsible for the financing, design, and construction of the project. Operating. Throughout the concession period, the project company obtained profits through the operation of the project and used the profits to repay the debt. At the end of the concession period, the entire project was handed over to the host government by the project company at no cost or at a nominal price. The most important feature of the BOT model is that due to obtaining government permission and support, preferential policies are sometimes obtained and financing channels are broadened. BOOT, BOO, DBOT, BTO, TOT, BRT, BLT, BT, ROO, MOT, BOOST, BOD, DBOM, and FBOOT are all different evolution methods of standard BOT operations, but their basic characteristics are the same, that is, the project company must Get the concession granted by the relevant government department. This model is mainly used for infrastructure projects such as airports, tunnels, power plants, ports, toll roads, telecommunications, water supply, and sewage treatment, which have large investments, long construction periods, and can operate profitably. 1) Advantages It can reduce the government's responsibility for sovereign debt and debt service; it can transfer the risks of public organizations to private contractors, avoiding the public organizations to bear the full risk of the project; it can attract foreign investment to support the construction of domestic infrastructure and solve the development problem. Chinese countries lack the issue of construction funds; BOT projects are usually contracted by foreign companies. This will bring advanced technology and management experience to the countries where the project is located. It will not only bring more development opportunities to the contractors in the country, but also promote The integration of the international economy. 2) Disadvantages: Within the concession period, the government will lose control over project ownership and operation rights; there are many parties involved, the structure is complex, the project is too long and the financing cost is high; it may lead to a large amount of tax loss; it may cause predatory operations of the facility; After the completion of the project, there will be a large amount of foreign exchange outflow; risk apportionment and other asymmetry. Although the government has transferred risks such as construction and financing, it has assumed more other responsibilities and risks, such as interest rates and exchange rate risks. 7. Public-Private Partnership (PPP) The model of non-governmental participation in the construction of public infrastructure and the management of public affairs is collectively referred to as Public-Private Partnership (PPP). Specifically, it refers to a franchise project financing model in which the government and private enterprises form a mutual cooperation relationship based on a certain project. The project company is responsible for financing, construction and operation. The government usually enters into a direct agreement with the financial institution that provides the loan. This agreement is not a guarantee for the project. It is a commitment made by the government to the lending institution. It will pay the relevant fees according to the contract signed between the government and the project company. This agreement enables the project company to obtain loans from financial institutions more smoothly. The project's expected return, assets, and government support will directly affect the number and form of loans. The essence of adopting such a form of financing is that the government will provide the long-term franchise and income rights for private enterprises in exchange for infrastructure construction and efficient operation. The PPP model is applicable to projects with large investment, long construction period and slow return on capital, including railways, highways, bridges, tunnels and other transportation departments, electricity and gas and other energy sectors as well as telecommunication networks and other communications businesses. Whether in developed or developing countries, the application of PPP mode is more and more extensive. The key to the success of the project is that the participants and shareholders of the project have clearly understood all risks, requirements, and opportunities of the project before they can fully enjoy the benefits of the PPP model. 1) Advantages: The public sector and private enterprises participate in the demonstration at the initial stage, which helps to determine the feasibility of project financing as soon as possible, shorten the preparatory work cycle, and save government investment; the risk allocation can be realized at the early stage of the project, and the risk can be allocated more because the government shares some risks. Reasonable, reducing the risk of contractors and investors, thereby reducing the difficulty of financing; Private companies involved in project financing to participate in the early stages of the project, is conducive to private companies to introduce advanced technology and management experience from the beginning; Public and private companies participate in the construction and operation. Both parties can form long-term goals of mutual benefit, provide better services for the society and the public, and integrate the project participants into strategic alliances, which play a key role in coordinating the interests of different parties. The government has some control. 2) Disadvantages: For the government, how to determine the cooperation company has increased the difficulty for the government, and it has to bear certain responsibilities in the cooperation, which increases the government's risk burden; the organizational form is more complicated, which increases the difficulty of coordination in management; how to set the project The rate of return may become a controversial issue. to sum up The above cooperation modes are formed under different conditions, after market operations and inspections, but the cooperation mode is not fixed. The above 7 cooperation modes can be adjusted under specific conditions, and new ones can also be proposed after creation. The only criterion for the cooperation model is to meet the interests of all parties and meet specific conditions. 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