Modern construction industry is the pillar industry of national economy. Once there is a problem in the building, it will also have a great impact on people's production and life. An important factor affecting the building quality is the quality of reinforcement engineering. The quality of building engineering refers to the comprehensive requirements of environmental protection and beauty in the country. Construction engineering is a special product, which not only meets the needs and attributes of society, but also has the characteristics of one-off and long life. The quality of construction projects mainly includes three main parts: the quality of construction process, the quality of construction and the quality of the main body of construction projects. So how to judge whether a project meets the requirements? Let's introduce some problems in the project process and the methods to avoid them in detail.
1 quality improvement of reinforcement engineering
1. 1 Basic principles for judging the quality of reinforced concrete projects. Reinforced concrete engineering is the foundation of building engineering. The determination of reinforced concrete engineering quality should be based on building site selection, address investigation and structural design, including the selection and storage of engineering materials, the construction of building foundation and the construction of main building. Based on the ability to meet the usability and durability of buildings, there are special requirements for the selection of materials. Strictly judge whether the reinforced concrete project meets the quality standards stipulated in the contract and building codes according to the standard specifications. The required quality standard, that is, inferior reinforced concrete engineering, should be reformed or remedied by effective measures to achieve the required quality standard. Quality evaluation includes engineering material test, quality control during construction and quality inspection after construction. Therefore, determining the quality of reinforced concrete projects is based on various building codes for inspection and evaluation.
1.2 purpose and method of quality control of reinforced concrete engineering. Reinforced concrete has become a widely used building material in various buildings and structures. For the foundation and main works of the building, reinforcement is needed. It can be said that it plays an important role in supporting buildings, protecting, separating and coordinating buildings and structures. In building engineering, it is very important to control the quality of reinforced concrete from many aspects. Construction process control and guarantee and construction management. For the whole reinforced concrete project, the quality of raw materials and the main reference of curing technology are the key links to ensure the quality of reinforced concrete project. Therefore, it is necessary to analyze the influencing factors of reinforced concrete engineering quality of construction enterprises at these stages. Including the problems existing in the project, formulate specific improvement strategies to further improve the project, and at the same time provide better services for the society and create higher quality building products.
2. Quality control of reinforcement engineering in practical engineering.
In the process of building main body construction, the last process is reinforced concrete pouring, which should be highly valued. During construction, if the density of the foundation is not high, the foundation will easily settle and bend under certain mechanical action during pouring. In this way, in the process of paying attention to this aspect, seamless steel pipes should generally be selected for treatment. The diameter of seamless steel pipe can be selected as required. The pipe diameter is generally 22-25 cm, and the length of each section is about 2.50m m. The corresponding joint parts should be provided with a certain sealing ring and lubricated, and a short joint with a certain length should be reserved. When running into the hole, the conduit should be carefully checked, and unqualified conduit should not be selected, and the corresponding joint should meet certain firmness requirements. When the catheter is lowered, the distance between the end and the bottom of the hole should be properly controlled, not too far or too close. At the same time, the depth of buried pipe should be properly considered to avoid the influence of mud entry; When pouring, the corresponding holes should also be checked to avoid blockage.
2. 1 Used for the control of steel raw materials. Some steel raw materials are often piled up on the construction site, but they have not been used for a long time due to improper storage or problems in the warehouse itself. The phenomenon of surface corrosion of steel raw materials. At first, the surface of these steel bars was discolored floating rust. As time goes on, it gradually turns red or even dark brown, and what's more, the fish scales will fall off. Therefore, for the storage of steel raw materials, it is required to have a fixed shed area, the humidity should not be too high, it should be kept as dry as possible, and the storage period should be shortened as much as possible. For floating rust that has appeared, it should be treated before use, and for serious corrosion, it should be scrapped or degraded. Fig. 2 is a well-preserved steel bar in the field. It is necessary to avoid improper management of raw material warehouse and lax system; If the diameters are similar, they should be distinguished by visual inspection; There is a phenomenon that the technical certificate data is not put into storage at the same time as the reinforced material. Raw materials and processed semi-finished products of steel bars shall be classified and stacked, and nameplates shall be erected to indicate the materials and specifications. Before blanking, carefully check the materials and specifications according to the drawings and bill of materials, especially the secondary steel and the tertiary steel; Be familiar with the construction flow and process arrangement, and organize the construction.
2.2 Quality problems of steel raw materials. In practical work, in most cases, the area of steel bar processing site is relatively narrow, which can not meet the corresponding processing requirements. The finished product after the steel bar end is processed. The steel bars used in this process are basically processed, and a small number of steel bars are produced on site, which may have four quality problems. Changes in specifications, varieties and grades of steel (replacement, no design change documents. There is no ex-factory certificate and ex-factory inspection report for steel bars. The information in the ex-factory warranty of steel bars is inconsistent with the real thing. The mechanical properties test of steel bars does not meet the relevant requirements.
2.3 Construction drawing reinforcement. In the process of architectural design, the factors of "resistance" and "release" in the corresponding components should be reasonably coordinated to avoid the stress concentration problem related to the sudden change of structural section as much as possible. In this design, we should also choose the appropriate shrinkage compensation reinforced concrete technology. According to a lot of experience, the formation of construction cracks is closely related to concrete shrinkage. In order to solve this problem effectively, a part of expansive agent can be properly mixed into reinforced concrete. At the same time, relevant designers should also consider the reasonable arrangement of steel bars. In the process of designing thin-walled members, special attention should be paid to these problems, such as the design of floor and wallboard, to ensure that the corresponding number of steel bars meets the requirements. In addition, the construction personnel should also be familiar with the relevant knowledge of steel structure, and should be dealt with in time if the construction drawing is found to be inconsistent after inspection.
2.4 steel bar displacement. In the process of construction site, quality problems of steel bars often occur, such as steel bar joints and steel bar breaks. Table 1 analyzes the common phenomena in reinforcement field engineering, and introduces the problems, causes and solutions in detail.
3 quality control of reinforcement engineering
3. 1 quality control points for steel bar installation. Steel bars play an important role in architecture. Reinforcement installation is closely related to reinforcement construction. The quality of steel bar installation directly affects the overall quality of the project. Therefore, this work needs the supervision of quality engineers. When installing steel bars, it is important to check whether the specifications, quantity and varieties of steel bars meet the installation requirements. For the abnormal situation in the installation stage, the quality engineer needs to carefully check the specific treatment process in the construction site, especially the structure of the frame surface structural beam and the boundary anchorage, and pay attention to the structure in the anchorage column of the simply supported frame beam in the transfer floor for some projects. In the process of steel bar installation, the key point of inspection is the cantilever part to ensure the position and height of cantilever steel plate, and it is also necessary to check the design involving reinforcement; The location of the steel bar binding connection joint should be set in the place where the tensile stress of the steel bar of the component is small. If the connecting joint must be placed under high tensile stress, the proportion of products in the same connecting section should not be greater than 50%.
3.2 Key points for quality control of steel bar processing. According to a lot of experience, the quality of reinforced concrete whole structure is closely related to the quality of corresponding reinforcement materials, so the quality of reinforcement should be strictly controlled. Quality engineers often forget to control the processing quality of reinforced materials, and the inspection of the processing quality of reinforced materials is mainly carried out on the spot and accepted at the installation stage. In this acceptance process, if there is a problem with the processing quality of steel bars, it needs to be reworked. In this case, it is easy to waste a lot of manpower, material resources and financial resources, which will affect the smooth completion of the project. Therefore, quality engineers need to monitor the processing process of steel bar materials to control the qualified rate of steel bar processing quality. Therefore, it is necessary to make a careful inspection.
3.3 Quality control points of steel bar connection. The welding process of steel bars is important, with high risk factor and high professional requirements for employees. Therefore, it is necessary to carry out trial welding before welding, and normal welding can only be carried out after the trial welding meets the requirements. After welding, relevant personnel shall be arranged for certain inspection. Install the steel bar joint in a position with less stress. In the longitudinal direction, multiple joints cannot appear at the same stress position, and the length from the end of the joint to the starting point of the steel bar curve should exceed ten times the diameter of the steel bar. Joints of the same assembly cannot overlap or be adjacent. The joint area of longitudinal stress of steel bars in the same connection section should meet the proportion specified in the design. If it does not meet the design requirements, it should comply with the provisions of the layout: the tensile area should not be greater than 50; If there are seismic requirements, there should be no joints in the stirrup encryption area at the beam end and column end of the frame; Welded joints should not be used in structures that directly bear dynamic loads. For welding, if problems are found during post-installation acceptance, it will greatly consume resources and seriously affect the progress of the project. It can be seen that the position arrangement of welded joints is very important. Quality inspectors shall conduct quality acceptance of welded joints in batches, and both appearance and mechanical properties shall be tested during inspection, but the order is different, among which the appearance of welded joints shall be mainly tested, and then the mechanical properties shall be tested, which shall be carried out by relevant quality inspectors before installation. After installation, it is important to check the longitudinal stress parts of the steel bar to ensure that the joint parts meet the requirements.
Generally speaking, in addition to the selection, proportion and construction of reinforced concrete construction projects, the lack of professionalism, comprehensive quality, sense of responsibility and quality management of construction personnel is also an important reason. In view of these problems and reasons, it is required to ensure that the reinforced concrete project can achieve the goal of high quality, low consumption and environmental protection from the aspects of engineering design, material selection, laboratory testing and company management system.
The above factors affecting the quality control of reinforcement engineering are collected and sorted by Zhong Da Consulting Company. For more "Influencing Factors of Quality Control of Reinforcement Engineering", please pay attention to the column of Zhong Da Consulting Industry. "It is easy to win the bid with a little construction." For information about construction enterprises, award-winning achievements, builders under construction, enterprise honors, qualification grades, industrial and commercial information, legal proceedings, etc., please visit Zhong Da Consulting, Construction Link or follow the official account of Zhong Da Consulting WeChat for enquiries.
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