What should I do with a refurbishment?

 

        Development of assembly-style building is a major change in the way of construction, is to promote the construction industry on the side of the structural reform of the important initiatives, is conducive to saving resources and energy, reduce construction pollution, improve labor productivity and quality and safety level, is conducive to promoting the construction industry and information The deep integration of chemical industry, so that the cost of the assembly-style building is getting higher and higher, more in line with the requirements of green buildings. At present, the assembly of buildings in the pilot exploration stage, there are still some uncertain factors, the need for a summary of the process. For the assembly of construction bidding, the current problems and difficulties, such as: the lack of assembly-type construction of the national operating technical regulations and provinces and cities supporting the bill of quantities specification, tender and tender procedures in the development of exploration, immature Evaluation methods, to grasp the lack of construction technology enterprises, the state, provinces and cities did not develop assembly-type bidding and other tender methods. Therefore, the issue of the tender for the construction of the tender needs to be studied in the actual work to solve.

 

1. Analysis of the status quo of assembly construction bidding

         First, all localities have formulated policies to support the development of assembly buildings. The most common are six types of policy support: First, land security. In the construction of land on the priority to support the development of the assembly of the construction industry. Second, the area award or volume rate reward. Generally given no more than 3% of the floor area rate of incentives, prefabricated exterior wall is not included in the building area. Third, financial incentives (subsidies). Such as the provisions of Shanghai, the assembly of 100 yuan per square meter subsidy, the maximum subsidy of a single project 10 million yuan. Chongqing City, 350 yuan per cubic meter of concrete components subsidies. Fourth, tax incentives. Shall be exempted from corporate income tax or enjoy the value-added tax that levy 50% of the policy. Fifth, the provisions of the construction of the commercial housing can be pre-sale in advance. Construction site to reach ± ​​0.000, can apply for "commercial housing pre - sale permit. Six is ​​to give the fund back. Exempt from the new wall materials special fund, the completion of acceptance after the acceptance of new wall materials special funds can be implemented preferential return.

         Second, in order to promote the development of assembly-style buildings, many parts of the country issued a fixed rating of the building. 2016 years ago has released areas including Shanghai, Liaoning, Shandong, Anhui, Fujian, Hunan, Sichuan. Tianjin, Henan, Hebei, Zhejiang, Shenzhen was released in 2016. Inner Mongolia, Qinghai, Jiangsu, Hubei, Guangdong is also about to release.

Third, all around the assembly-style construction of the regulatory mechanism is also innovative, in the assembly of building bags in all directions to promote the project general contracting model. Jinan City, with component production qualification, the total investment to a certain size of the general contracting enterprises, in the bidding to give bonus points. Construction of the project in accordance with the design, component production, construction, installation of integrated procedures for the general contracting enterprises, project bidding, the same conditions under the priority bid. Design, construction, installation, supervision and other enterprises to participate in the construction of assembly projects to achieve a certain scale, in the bidding to give bonus points. Hefei City, the provisions of the pilot in the early part of the pilot project to take a single source to determine the assembly of construction enterprises, the cost of the use of traditional methods and industrialization to compare the way to the industrial enterprises a certain profit margins, and gradually with the market Convergence. In the future, all the assembly projects will be open tender, take the design and construction general contracting way, from the industrial enterprises from the design, parts and components to the construction of assembly, the whole process of general contracting, the bid price significantly reduced construction period greatly shortened.

It is foreseeable that as the market system matures, the bidding process is gradually standardized, the construction cost of the assembly building will be gradually reduced.

 

2. Introduction to the bidding process of the assembly building

        In accordance with the relevant provisions of the requirements, the assembly of construction in principle should be used in general contracting. Therefore, the author first introduced EPC (design - procurement - construction) project general contracting model. In the EPC project general contracting mode, the scope of commissioned construction of the tender includes: design, procurement, construction and commissioning. Organizational implementation principles for the unified planning, unified organization, unified command, unified coordination. Should be from the construction scale, construction standards and responsibilities, such as the division of the tender requirements to develop.

        In addition, the requirements of the tender for the construction of the tender tenders include: First, with the general contract management capacity of enterprises, can be design, construction, developers or other project management units. Second, with the corresponding qualification level of the design, construction or project management unit independent or composition of the Commonwealth bid. Third, due to the current construction market with a total contract performance of the unit less, in the tender should not be the general contract performance as a tender conditions to promote the development of the general contracting industry.

        EPC project general contract tender in the demand for a unified, clear under the premise of the bidders according to a given conceptual program (or design), construction scale and construction standards, the preparation of estimates of the bill of quantities and quotation. It is recommended to use the total price of the package pricing model, but the underground project should not be included in the scope of total price package, but should be used to simulate the amount of unit price contract, according to real measurement. If you need to agree on the material, the adjustment of labor costs, the proposed tender when the first fixed adjustment materials, labor in the total proportion of the total cost of the project to the bid price of the project cost multiplied by the proportion as a base, The proposed adjustment method to be adjusted.

         Assembly of construction bidding on the evaluation and calibration are also required. To be careful to determine the bidder's general contract management capacity and performance capacity, the tender to deepen the design of the tender requirements in line with the requirements of the tender offer is reasonable.

 

3. Electronic evaluation of assembly-type bidding

         In reality, the difficulties in the evaluation of the tender documents of the assembly building are focused on the design scheme, the construction plan and the bidding offer. I believe that, for the assembly of construction bidding, based on BIM (building information model) of the electronic evaluation will be more scientific and efficient.

         Electronic evaluation system based on BIM should be established. In the bidding and bidding phases, the following areas are included: modeling or model introduction, construction program preparation and optimization (simulation), preparation and optimization of construction schedule, preparation and optimization of resources and funding programs, preparation and optimization of construction projects, tender documentation (Bidding, bidding), online bidding system, construction schedule planning software, site layout program preparation software, pricing software. In the evaluation stage, the need for the construction program than the selection and evaluation, construction 5D review, resource planning review, construction special program review, design review, should have the electronic (remote) evaluation system, BIM technical evaluation trial subsystem. BIM-based bid review specifically includes the following:

 

       One is the model check. The object information, time information and optimization rationality are reviewed intuitively. The types of floors and professional components to be viewed are selected, and the rationality of construction parameters and construction plan is reviewed through the property window. The traditional graphic text into a three-dimensional observation of the three-dimensional information model to enhance the evaluation process of targeted and in-depth level.

 

       Second, the progress of simulation. The progress simulation is a visual review of the progress schedule of the technology standard. The progress schedule of the technology is reviewed in the form of 4D animation. The construction order and rationality of the different professional models in the construction plan are viewed through the multi-window. The progress of the text and the chart is changed. Standard experts to deepen the understanding of the construction organization, to make accurate judgments.

 

       Third, capital resources check. This step is a multi-dimensional display of bidders' funds and resource use plans. From the current value or the cumulative value of the point of view, month, week, day different time units, according to the smoothness of funds to determine the rationality of the funding plan. This step is convenient for the evaluation of experts to conduct a comprehensive and in-depth assessment of the resource resource plan.

 

       Fourth, the venue layout program evaluation. This is a three-dimensional display of the construction site and temporary facilities layout, through the three-dimensional site and the physical model, the combination of measures to model, to roam the way from different viewing perspective, the venue layout review. Can change the two-dimensional plane drawings can not be intuitive display site layout and technical solutions to improve the accuracy of the results of the assessment.

 

       Five is the key node program review. This is mainly in the form of animation to show the most difficult construction program, direct animation and play video two ways to double the difficult parts of the construction process to check, change the traditional lengthy text description, and enhance the intuitive experience, easy to evaluate the standard Difficult to understand the program, while reducing the threshold of the animation program.

 

        Six is ​​the tender offer review. The use of BIM technology to provide the overall view of the bill of quantities to view the function, starting from the project as a whole, a comprehensive and detailed display of the bidder business standard content, visual display of the contents of the overall list, combined with large data applications, easy to find experts in the project offer problems The

 

        Seven is a direct fee check. Criteria for visualizing the BIM model area selected by the expert. Through the check box, box selection, component query, etc., quickly sort out the need to review the component items to three-dimensional information model and data combination of the way from the component level presented business standard data, easy evaluation experts intuitively, in-depth found that The problem.