Construction Organization and Management

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Any project involves construction work, and there will also be **small problems**. I present here the book \"Construction Organization and Management\"; I’ve glanced through it briefly and found it quite informative! But the file is too large; attachments cannot be uploaded... Let’s upload the content of Chapter 1 first. With the modernization and advancement of construction technology, the production of building products has become a comprehensive and complex systematic project. Whether in terms of scale or functionality, some of them soar high into the sky, some have enormous spans, and some extend deep underwater, which poses many complex and difficult challenges for construction. To carry out construction preparation work properly, it is necessary to conduct on-site surveys and investigations of the project to be built in order to obtain first-hand data. This is essential for developing an advanced, reasonable, and practical construction organization plan. How to select the optimal and most feasible solution among numerous factors such as the construction season, environmental conditions, project duration, the skill level and number of workers, the availability of machinery and equipment, material supply, component production methods, and transportation conditions is an issue that construction workers must address before starting work; it is also the key focus of this chapter. 1.1 The Role and Classification of Construction Organization 1.1.1 The Object of Study in Construction Organization Construction organization involves studying the objective laws of overall planning and systematic management in construction projects, in light of the complexity associated with such projects. It is a form of production organization that entails the allocation of resources in a manner appropriate to the unique characteristics of single-unit production in construction projects (products). Different buildings or structures have distinct construction methods. Even for buildings or structures designed according to the same standards, the construction methods cannot be exactly the same due to differences in the location of construction. Therefore, there is no universally uniform and fixed construction method available to choose from; instead, different construction organization plans must be developed for each specific project. Therefore, it is necessary to study in detail the characteristics of the project, the regional environment, and the conditions of construction. From an overall construction perspective as well as from a technical and economic standpoint, it is essential to follow the requirements of the construction processes, arrange the spatial layout and timing of the construction activities in a rational manner, organize the supply and consumption of material resources scientifically, and better coordinate the relationships between various units, departments, and construction phases involved in the project. This requires unified planning to be carried out before the construction of the project begins, and it needs to be scientifically expressed through a construction organization plan. 1.1.2 The role of construction organization design: Construction organization design is a comprehensive technical and economic document that plans and guides the entire process of a project, from preparation for construction to completion and acceptance. It serves as a bridge between project design and construction; it must reflect both the design and operational requirements of the project as well as the objective laws of construction work, playing a role in formulating strategic plans or tactical arrangements for the whole construction process. (1) The construction organization design can guide project bidding and the signing of project contracts, and serve as part of the bid document and the contract paperwork. (2) The construction organization design is an important part of the construction preparation work; it enables scientific management of the construction process to ensure that the preparatory tasks for each construction phase are carried out on time. (3) The construction organization design is an important means for implementing scientific management throughout the construction process of a project to be built, and it serves as a basis for monitoring the three key objectives of project construction: progress, quality, and cost. (4) By preparing the construction organization plan, methods of construction, construction sequence, as well as labor and technical organization measures are determined, thereby improving overall efficiency. 1.1.3 Classification of construction organization design: Construction organization design can be classified in the following ways, based on different design stages, the scope of the subjects involved in its preparation, and the complexity of its content. 1. Classification by different design stages: 1) Pre-bid design. Pre-bid design covers the scope of work related to bidding and signing of project contracts; it is prepared by the management team prior to bidding, and the quality of this pre-bid design is a key factor in determining whether a bid will be successful. 2) Post-marking design: Post-marking design covers the period from construction preparation to construction acceptance. It is prepared by the project management team after the contract is signed but before work begins, and it serves to guide the construction of the entire project in the absence of a prior plan. 2. Classification according to the scope of the subject for which it is prepared: Construction organization designs can be classified, based on the scope of the subject for which they are prepared, into general construction organization designs, construction organization designs for individual (or single) projects, and construction organization designs for specific components or tasks of a project. 1) General construction organization plan: The general construction organization plan is a comprehensive document of technical, economic, and organizational nature that is prepared for a building complex or a construction project, and it serves to guide all the construction activities throughout the entire process of building that complex or carrying out that project. The general construction organization plan is generally prepared after the preliminary design or expanded preliminary design is approved, under the leadership of the chief engineer of the general contracting company, in collaboration with the construction party, the design team, and the subcontractors. 2) Construction organization design for a unit (or individual) project: The construction organization design for a unit (or individual) project is a guiding document of technical, economic, and organizational nature that is prepared for a specific unit project (a building or structure), and it serves to guide the entire construction process. The construction organization design for a unit project is generally prepared under the leadership of the technical supervisor of the project team, after the construction drawings have been completed and before the start of construction of the project. 3) Construction organization design for individual construction tasks: The construction organization design for individual construction tasks is a comprehensive document of technical, economic, and organizational nature, prepared for those construction tasks that are difficult to carry out or involve complex technologies. It serves to outline all the construction activities required for the complete execution of such tasks. The construction organization design for sub-projects and individual tasks is generally prepared simultaneously with the construction organization design for the entire project, and it is the technical personnel in charge of the overall project who are responsible for its preparation. 3. Classification by the level of complexity of the content: 1) Comprehensive construction organization plan. For projects that are important, large in scale, complex in structure, require high technical standards, and involve the use of new structures, technologies, materials, and processes, it is necessary to prepare a construction organization plan that is detailed and thorough. 2) A concise construction organization plan: For projects with a small scale, simple structure, and low technical requirements, a construction organization plan that includes only basic elements such as the construction plan, construction schedule, and construction layout diagram can be prepared. 1.2 Construction Procedures and Building Processes 1.2.1 Construction Projects and Their Components A basic construction project, simply referred to as a construction project, generally means a construction work that is carried out within the framework of an overall design or preliminary design; once completed, it forms a complete system that can independently generate production capacity or possess utility value – such a project is considered a construction project. For example, in industrial construction, such as a power plant or a cotton mill, etc ； In civil construction, such as a school, a hospital, etc. An enterprise or institution that carries out capital construction is called a construction unit. The construction unit is administratively organized independently and managed in a unified manner, with unified economic accounting; it can establish economic relationships with other units directly. Construction projects can be classified from different perspectives. For example, construction projects can be classified into large-scale, medium-scale, and small-scale projects based on their size ； Based on the nature of the construction project, they can be classified as projects to increase production capacity, such as new construction, expansion, or renovation ； According to the different specialties of construction projects, they can be classified into industrial and civil building projects, transportation engineering construction projects, water conservancy engineering construction projects, etc ； Based on the purpose of construction projects, they can be divided into productive construction projects (including those in industry, agricultural water management, transportation and telecommunications, commerce and material supply, geological resource exploration, etc.) and non-productive construction projects (including those for housing, education and culture, health care, and public services). Knowledge link: To meet the needs of decomposed management in construction projects, these projects can be broken down into individual works, unit projects, sub-projects, and detailed tasks. Application Case 1-1 takes a hospital construction project as an example; its decomposition can be referred to as shown in Figure 1.1. Figure 1.1 Decomposition of a hospital construction project 1) Individual project (also known as a construction project) An individual project is one that has its own separate design documents, can be constructed independently, and can operate to produce capacity or deliver benefits on its own once completed. A construction project can consist of a single unit project or multiple unit projects. In civil construction projects such as outpatient and inpatient buildings in hospitals, as well as teaching and dormitory buildings in schools, these can all be considered individual projects. Their scope includes building construction, equipment installation, as well as utilities such as water, electricity, and heating systems. 2) Unit project: A unit project is a project that has its own design and can be constructed independently, but it cannot operate to generate production capacity or benefits on its own after completion. A single project can be composed of several sub-projects. For example, a production workshop generally consists of various sub-projects such as civil engineering, industrial piping engineering, equipment installation engineering, water supply and drainage engineering, and electrical lighting engineering ； A outpatient building is also composed of individual construction elements such as civil engineering, equipment installation, plumbing, and electrical lighting works. 3) Sub-projects: Sub-projects are components of a larger project; they are typically classified based on the location of the work, structural design, type of specialty involved, and the materials used. For example, the civil engineering components of an outpatient building can be divided into sub-projects such as foundations, the main structure, the roof, and interior decoration, based on their structure or functional areas ； According to its quality inspection and evaluation requirements, it can be divided into foundation and substructure, main structure, floors and surfaces, doors and windows, decoration, roof works, etc. 4) Sub-projects (also known as construction processes) are components of larger projects; they are those that can be completed through relatively simple construction processes. The volume of work and its unit price can be calculated using appropriate measurement units. Sub-projects are generally classified based on factors such as construction methods, main types of work involved, materials, and the specifications of structural elements. For example, the foundation of a brick-concrete structure can be divided into sub-projects such as soil excavation, concrete cushion, brick foundation, and backfilling ； The main concrete structure can be divided into sub-projects such as installing formwork, binding rebar, and pouring concrete. Special note: Several sub-projects make up a sub-work; several sub-works constitute a single work; several single works form a project; and several projects comprise a construction project. ? A simple construction project may also consist of just one single task. 1.2.2 Characteristics of construction projects The characteristics of construction projects are mainly reflected in two aspects: its outcome—the building products—and the production process of those building products. 1. Characteristics of construction products 1) Large size of construction products: To fulfill their functional requirements, construction products require a large amount of material resources and occupy substantial areas both on the ground surface and in terms of space; compared to ordinary industrial products, they are much larger in size. 2) Fixed nature of construction products: Construction products are fixed in the location where they are used; they are connected to the foundation buried deep underground. Therefore, they can only be produced and used at the place of construction, cannot be moved around, and cannot circulate like ordinary industrial products. 3) Diversity of building products: Different building products vary in terms of construction scale, structural type, architectural design, foundation design, and usage requirements. Even building products of the same type can vary from one another due to differences in location, terrain, geological and environmental conditions, as well as the type of materials used. 4) The comprehensiveness of building products: Building products involve not only various technical aspects and specialties related to the architectural functions, structural design, and decorative elements of construction projects, but they also incorporate various facilities such as process equipment, heating and ventilation systems, water and power supply, and communication networks. Therefore, building products represent a complex organic whole. 2. Characteristics of construction 1) Long construction period: The large volume of construction products determines that the construction process takes a long time. The volume of work involved in building products is enormous; a great deal of human, material, and financial resources are required for their production. It demands the cooperation and joint effort of various types of workers and teams, and it takes a long time to complete such production. 2) Mobility in construction work: The fixed nature of building products determines the mobility in their production. For general industrial products, the location of production, the producers, and the production equipment are fixed, with the products moving along production lines. Construction, on the other hand, is different: building products are fixed, and the producers involved in construction, as well as materials and production equipment, not only need to move as the location where the building product is constructed changes, but also keep moving around in space depending on the different parts of the building that are being constructed. 3) The uniqueness of construction projects: The fixed location of building products and the diversity of their types determine the uniqueness of building production. Each building product is designed and constructed according to the requirements and plans of the construction party, with distinct design processes, construction methods, and feasible construction plans developed based on its functional purpose and location, thereby ensuring that each building project is unique. 4) Complexity of construction: The complexity of construction products determines the complexity of building construction. The production of building products is a process that requires a long time, involves significant workload, high resource consumption, and involves a wide range of specialties. It involves various specialties such as mechanics, materials, architecture, structure, construction, hydraulics, and equipment; coupled with the mobility and uniqueness of each construction project, this makes the organizational coordination in building construction highly complex. 1.2.3 Capital construction procedures The capital construction procedures refer to the sequence that various tasks must follow throughout the entire process of a construction project, from decision-making, design, construction, and completion inspection to commissioning or putting the project into use. They represent the objective rules that must be adhered to throughout the construction of a project. This sequence is neither arbitrarily arranged by humans nor can it change with the location of construction; rather, it is determined by the basic construction process. Considering the objective laws of capital construction, the characteristics of projects, and the scope of work involved, it is necessary to ensure that the various stages and aspects of project construction are interconnected within a multi-level, multidimensional framework and within a limited time frame in order to organize capital construction effectively. The capital construction process in our country can be divided into eight stages: project proposal, feasibility study, design documents, construction preparation (including bidding and contract signing), construction implementation, production preparation, completion acceptance, and post-evaluation. These 8 stages can be further summarized into three major phases, namely the project decision-making phase, the project preparation phase, and the project implementation phase. 1. Project decision-making stage: The project decision-making stage includes elements such as project proposals and feasibility studies. 1) Project proposal: A project proposal is an overall outline of the proposed project. It is formulated in accordance with the **long-term plans for national economic and social development, industry plans, and regional plans, as well as** industrial policies. Through research, market forecasting, and technical analysis, it focuses on providing a macro-level assessment of the necessity for carrying out the project, as well as a preliminary evaluation of its feasibility. A project proposal is a recommendation document submitted by the project owner to the relevant authorities requesting the construction of a particular project. For large and medium-sized projects, those with complex technological processes, wide scope of involvement, and high levels of coordination, a feasibility study report must also be prepared as one of the main attachments to the project proposal. The project proposal represents the initial stage of the project development cycle; it serves as the basis for **selecting a project as well as for conducting feasibility studies. In the case of projects that involve foreign investment, external activities can only commence after the project proposal is approved. The content of a project proposal varies in complexity depending on the specifics of the project, but it generally should include the following aspects. (1) The rationale for proposing the project, which mainly outlines the current situation of the project owner, the name of the proposed project, its nature, the location where it will be constructed, as well as the reasons and basis for carrying out this project. (2) The preliminary construction plan for the project, including the scale of construction, main contents, and functional distribution, etc. (3) Project construction conditions, as well as the progress of various aspects of the project construction and its duration. (4) The total investment amount for the project and the arrangement of funds for its main construction, as well as the methods and plans for raising funds. (5) Preliminary estimates of the economic and social benefits after project completion, including preliminary financial evaluation and national economy evaluation. Once the project proposal is prepared in accordance with the requirements, the approval authority is determined based on the overall scale and budget limits, and the proposal is submitted for approval. 2) Feasibility study: Once the project proposal is approved, the feasibility study can be carried out. A feasibility study is a thorough and detailed investigation into the social, economic, technical, and other aspects related to a proposed construction project prior to making an investment decision. It involves a careful technical and economic analysis and comparison of various possible design and construction solutions, as well as a scientific prediction and evaluation of the economic benefits that will arise once the project is completed. On this basis, a comprehensive analysis, systematic evaluation, comparison of various options, and overall assessment are carried out regarding the technical advancement and suitability, economic rationality and effectiveness of the proposed project, as well as its necessity and feasibility. Conclusive opinions are thus derived on whether to invest in the project and how to do so, providing a reliable scientific basis for investment decisions in this project. The content of a feasibility study report for a construction project can be summarized into three main parts. First is market research, which includes market surveys and forecasting studies for the proposed project. This constitutes the premise and foundation for feasibility studies of the project, and its main task is to address the issue of the project’s \"necessity\" ； The second is technical research, namely the study of technical solutions and construction requirements; this constitutes the technical foundation for the feasibility study of a project, as it aims to address the issue of the project’s technical feasibility ； The third is benefit analysis, that is, the examination and evaluation of economic benefits. This constitutes the core part of a project feasibility study, addressing primarily the issue of the project’s economic \"reasonableness\". Market research, technical research, and benefit analysis together constitute the three main pillars of project feasibility study. Based on the feasibility study, a feasibility study report shall be prepared, and the completed report must be submitted to the relevant authorities for approval in accordance with regulations. The approved feasibility study report serves as the basis for the preliminary design and must not be modified or altered arbitrarily. 2. Project preparation phase: The project preparation phase mainly includes the preparation of design documents and construction preparations. At this stage, the main tasks involve establishing a project entity based on the approved feasibility study report, carrying out preliminary design and detailed construction drawings, preparing an estimated cost for the design, formulating annual construction and investment plans, conducting bidding for the project, signing construction contracts, and preparing equipment, materials, and the construction site. 1) Design documents: Design documents serve as the main basis for planning construction projects and carrying out building work. Design documents are generally prepared by the project owner through bidding or by entrusting a design firm with the appropriate qualifications to carry out the design work. When preparing the design documents, the requirements of the construction project should be translated into engineering drawings and their accompanying specifications that guide construction, based on the approved feasibility study report. The design is carried out in stages. For small and medium-sized construction projects, a two-stage design process is generally adopted, namely preliminary design and construction drawing design. For large-scale projects or those that are technically complex, a three-phase design approach can be adopted, namely preliminary design, technical design, and construction drawing design. (1) Preliminary design. The preliminary design is a preliminary design document prepared based on the approved feasibility study report or design assignment. The preliminary design documents consist of four parts: the design specification (including the general design description and the design specifications for various specialties), the design drawings, a list of major equipment and materials, and the project cost estimate. During the preliminary design phase, each specialty shall conduct a comprehensive technical and economic analysis of the design proposals for its own area of work or of the solutions to major technical issues, in order to assess their technical suitability and reliability as well as their economic viability; the main findings of this analysis shall be included in the preliminary design documentation for that specialty. The chief design officer discusses the overall design of the engineering project in the general design specifications. The preliminary design is approved by the project owner. Once approved, the control parameters such as the scale of construction, the location of construction, the main processing procedures, the key equipment, and the total investment shall not be altered arbitrarily. (2) Technical design. Technical design involves further addressing various technical issues related to architecture, structure, processes, equipment, etc., on the basis of the preliminary design. It is necessary to clarify the main dimensions of the plan, elevation, and section views, determine the main architectural elements, select the key components and equipment, and resolve any conflicts between different specialties. Technical design is the foundation for producing construction drawings, and it also serves as the basis for ordering equipment and preparing for construction. (3) Construction drawing design. Construction drawing design is the final stage of architectural design. Its main task is to meet the construction requirements; that is, based on the preliminary or technical design, it integrates the efforts of various specialties such as architecture, structure, plumbing, electrical systems, and HVAC, ensures proper communication among them, conducts thorough verification, and gains a deep understanding of factors such as material supply, construction techniques, and equipment. It then reflects all the specific requirements for the construction project in the drawings, ensuring that the entire set of drawings is complete and accurate. The contents of construction drawing design mainly include: determining all project dimensions and materials required, drawing all construction drawings for the building structure and equipment, as well as project specifications, structural calculations, and construction drawing budgets. 2) Construction preparation: The construction preparation work can begin after the feasibility study report is approved. The following preparatory work must be carried out before the implementation of the construction project: land acquisition and demolition, as well as ensuring \"three connections and one leveling\" (water supply, electricity supply, road access, and site leveling) ； Engineering geological survey ； Collect basic design information and organize the review of design documents ； Organize equipment and place material orders ； Prepare the necessary construction drawings ； Organize construction bidding, select the best contractor, sign a construction contract, and handle the procedures for starting construction, etc. Proper preparation for construction projects plays a crucial role in ensuring better project quality, reducing costs, and accelerating the construction pace. Special note: For detailed information on the construction preparation work, please refer to Section 1.3. 3. Project implementation phase The project implementation phase is the longest, most labor-intensive, and most resource-consuming stage in the capital construction process. The focus of work at this stage is to carry out construction and installation based on the design drawings, which also includes preparing for production or use, conducting completion inspections, and performing post-evaluations. 1) Building construction: Building construction refers to the entire process by which workers with relevant production experience and technical skills, using necessary construction equipment, purposefully move, process, shape, and install various building materials (including finished or semi-finished products) in accordance with specific requirements, in order to produce building products of satisfactory quality. It is the process of turning plans and blueprints into physical structures. Before construction, it is necessary to conduct a thorough review of the drawings. During construction, work must be carried out strictly in accordance with the construction drawings and the records from the drawing review; any changes require the approval of the project owner and the design team ； Before construction, a construction drawing budget and a construction organization plan should be prepared, specifying the control requirements for investment, schedule, and quality, and these must be approved ； During construction, the relevant construction standards and specifications must be strictly followed to ensure project quality, and the construction tasks must be completed in accordance with the provisions of the contract. 2) Production preparation: Production preparation is an important task carried out by the project owner prior to the start of production; it is a necessary condition for transitioning from the construction phase to production and operation. The project owner shall promptly organize a dedicated team or agency to carry out the preparatory work for production. Production preparation work is determined according to the requirements of different types of projects, and generally should include the following items. (1) Establish production and management organizations, and formulate management systems and relevant regulations. (2) Recruit training personnel to improve the overall competence of production and management staff, so as to meet the requirements of production and operations. (3) Production technology preparation, including technical consultation, determination of operation plans, and job operation procedures. (4) Preparation of materials, including raw materials, fuel, tools and equipment, spare parts, and other supporting products. (5) Other necessary production preparations. 3) Completion acceptance: The completion acceptance of a construction project is an activity in which the employer, the contractor, and the project acceptance committee, based on the approved design specifications and documents for the project, as well as the construction acceptance standards and quality inspection rules issued by ** or relevant departments, carry out inspections and certifications, as well as comprehensive evaluations and assessments of the entire project after it has been built and passed trial production, following certain procedures and formalities. Completion acceptance is the final stage of a construction project. It requires that the individual construction units have been approved for acceptance, that all project documentation has been properly organized in accordance with regulations, and that necessary documents such as the completion report and final account have been prepared, before an application can be submitted to the competent authority for acceptance to take place. For industrial production projects, acceptance can only take place after the trial run with feed materials is successful, production capacity is established, and normal product manufacturing is possible ； For non-industrial production projects, they must be able to function properly before acceptance can take place. Knowledge link: After the preparation of the final settlement for completion, an audit must be conducted by an auditing authority; the audit report issued by this authority serves as the basic document for the completion acceptance. For projects of large scale and high technical complexity, relevant personnel can be organized to conduct a preliminary inspection; projects that fail this inspection will not be approved ； For projects with unresolved issues, specific solutions must be proposed, and rectification must be carried out within a set time limit. 4) Post-evaluation: With China’s successful accession to the WTO, there will be an increasing number of domestic international cooperation projects involving foreign entities. In accordance with international contracting practices, post-evaluation of construction projects is an essential part of it. Objectively speaking, the post-evaluation of construction projects in our country is still in its infancy. Based on foreign experience and the consensus of domestic experts, it is an inevitable trend to establish and improve a system for post-investment evaluation of projects in our country as a way to regulate the construction market and align it with international standards. Post-project evaluation refers to the process of, after a project has been completed and put into operation and has reached its designed production capacity, conducting a comprehensive analysis of the project’s preliminary stages, implementation process, and operational status. This involves assessing and analyzing the differences between the actual performance of the project and the predictions (plans) made initially, determining whether those predictions and judgments were accurate, and identifying the reasons behind any discrepancies. It also entails learning from the experiences gained during the project’s execution, in order to improve future decision-making, planning, management, and supervision related to projects. Additionally, it aims to develop practical and feasible strategies to enhance the profitability of project investments. This process generally includes the following elements. (1) The impact and evaluation of the actual operating conditions of the project after it reaches its designed production capacity. (2) The economic evaluation of the project after it reaches its designed production capacity consists of two components: the financial post-evaluation of the project and the national economic post-evaluation of the project. (3) Analysis and evaluation of the actual results versus the expected results after the project reaches normal production capacity. (4) Summary of work after the project is completed and put into operation. 1.2.4 Construction procedures The construction procedures represent the sequence and objective rules that must be followed throughout the construction phase of a planned construction project. It is generally divided into 5 steps. (1) Undertake construction tasks and sign construction contracts. (2) Make comprehensive arrangements and develop a proper construction plan. (3) Carry out construction preparations and submit a start-up report. (4) Carefully organize construction and strengthen scientific management. (5) Conduct project acceptance and hand over for production use. 1.3 Construction preparation work: The general process for a basic construction project is carried out in three phases: decision-making, preparation, and implementation. The design phase is further divided into two stages: preparation of design documents and construction preparation. It can be seen that the primary task of construction preparation work is to establish the necessary technical and material conditions for the construction of the project to be built, as well as to organize the construction workforce and the construction site in an appropriate manner. Construction preparation work is also the fundamental guarantee for construction companies to implement effective target management and ensure the smooth progress of civil engineering works and equipment installation. With the trend of construction projects moving deeper underground and higher above ground, the characteristics of being large-scale, complex, challenging, time-sensitive, and hazardous have become evident in such projects. Therefore, carrying out thorough preparation work for construction is of great significance for achieving goals such as leveraging the company’s strengths, ensuring proper allocation of resources, accelerating the construction pace, improving project quality, reducing costs, enhancing the company’s economic performance, gaining social credibility, and modernizing company management. 1.3.1 Classification of construction preparation work 1. Classification based on the scope and scale of the construction preparation work: (1) Overall construction preparation, also known as site-wide construction preparation, refers to all the preparations carried out for a particular construction project. Its purpose and contents are aimed at facilitating site-wide construction activities; it not only creates favorable conditions for such activities but also takes into account the preparation needs of individual construction tasks. (2) Preparation of construction conditions for individual (unit) projects. It refers to the preparatory work carried out for a building or structure; its purpose and scope are both aimed at serving that particular project. It involves making all the necessary preparations before the start of construction for that project, as well as creating the necessary working conditions for the construction of its various components. (3) Preparation of working conditions for sub-projects (individual tasks). It is the preparation of working conditions carried out for a specific sub-project or for construction work during winter or rainy seasons. 2. Classification according to the different construction phases of the project: (1) Pre-construction preparation work. It refers to all the preparatory construction work carried out before the official commencement of a project, with the aim of creating the necessary conditions for its actual start. (2) The construction preparation work after the project starts, also known as the preparation work prior to each construction phase. It refers to the preparatory construction work carried out after the commencement of the project and before the official start of each construction phase, in order to create the necessary conditions for each phase of construction. For the construction of mixed-structure residences, it is usually divided into construction phases such as underground foundation work, main structure work, roof work, and decoration work. The tasks involved in each phase are different, and the required materials, technical conditions, organizational requirements, and site layout also vary from one phase to another. Therefore, it is necessary to carry out the appropriate preparatory work before construction at each stage of the project. 1.3.2 Contents of construction preparation work The construction preparation work must be carried out throughout the entire construction process, and it should be done in a planned, step-by-step manner, phase by phase, according to the sequence of construction tasks. Based on the nature of the preparatory work, it can be roughly categorized into four aspects: preparation of technical documents, preparation of the construction site, preparation of resources, and preparation for seasonal construction. 1. Preparation of technical documents: The preparation of technical documents is extremely important in the overall construction preparation process; any technical errors or mistakes can lead to safety hazards and quality issues. Therefore, it is necessary to thoroughly carry out the investigation, research, and collection of technical materials. 1) Thoroughly review the preliminary design plan. Once the tasks are determined, it is necessary to communicate in advance with the design agency to understand the progress of preparing the preliminary design plan, ensuring that the design meets the requirements in terms of quality, functionality, manufacturing processes, and technology, so as to facilitate construction by removing any obstacles. 2) Familiarize with and review construction drawings. Familiarizing with and reviewing construction drawings mainly provides various bases for preparing the construction organization plan. Familiarity with the drawings is essential; technical and managerial personnel involved in construction must fully understand and grasp the design intentions, as well as the characteristics and technical requirements of the structure. They need to be able to follow the specifications outlined in the design drawings so as to produce building products that meet the design requirements. Familiarizing with and reviewing construction drawings is usually carried out in three stages: self-review of the drawings, joint review, and on-site visa. The self-review of the drawings is carried out by the construction unit, which also prepares a record of this self-review ； The drawing review is chaired by the project owner, with the design unit providing explanations; the construction unit and the supervision unit also participate in it. A minutes of the drawing review is prepared, which is then formally issued by the project owner. All parties involved sign it and affix their official seals to it, using it as a basis for guiding construction work and carrying out project settlement ； On-site visa for drawings refers to the process in construction projects where, if it is found that the actual conditions during construction do not match those specified in the design drawings, or if errors are detected in the drawings, the technical approval and design change visa system must be followed. Issues identified in this way are documented through on-site visas, which serve as a basis for guiding construction, conducting final inspections, and settling accounts. 3) Preparation of construction drawing budgets and construction budgets. A construction drawing budget is an economic document that outlines the cost of construction work and the requirements for various resources, prepared by the construction contractor based on the quantities determined from the construction drawings, the construction methods outlined in the construction organization plan, as well as the budgetary rates for construction work and related costs. A construction budget is an internal economic document prepared by the construction company based on documents such as construction drawings, construction organization plans or schemes, and construction quotas.