Concrete is a mixed material, which is composed of coarse aggregate, fine aggregate, cement and other additives, and cement will undergo heat of hydration reaction, which will lead to temperature cracks in concrete, which seriously affects the construction quality of housing construction projects.

The following author briefly introduces the causes of problems in the construction of concrete for housing construction and the causes of problems in the construction process, and analyzes the measures to improve the quality of housing construction, hoping to provide some help to the construction units.

In the future construction, effectively reduce the quality problems as well as safety hazards, reasonable application of concrete and other important construction materials, so as to extend the construction life of housing buildings.

　　1 The problems of concrete construction of housing buildings

　　1.1 Problems of concrete raw materials

　　In the housing construction project, there are many construction materials that need to be applied, in order to ensure the quality of construction, it is necessary to take effective tools for the transportation of materials, for concrete mixing materials, generally mixed at the construction site, if the concrete is transported over long distances, it will lead to an increase in the water-cement ratio of concrete, and it will also lead to the concrete becoming very thin, which is also the cause of the quality problems in the construction of concrete for housing buildings .

When mixing concrete on site, we also need to master the ratio of coarse and fine aggregates to ensure the thoroughness of flushing and to avoid the strength of concrete not meeting the standard. In some construction units, there are often problems of unreasonable coarse aggregate grading coefficients, the proportion of concrete ingredients is not reasonable enough, and the amount of cement paste is seriously insufficient, which are the reasons for the appearance of honeycomb pockmarked concrete members, and the unreasonable ratio is a major reason for reducing the strength of the concrete structure, which is also the main reason for the quality problems of housing construction projects, and needs to be paid attention to.

　　1.2 Problems of concrete construction process

　　Concrete construction process includes formwork engineering, concrete pouring and pounding, concrete demoulding and maintenance, etc. In formwork engineering, it is necessary to choose suitable formwork and then choose the best installation method, but in many building construction units there is no detailed plan for formwork installation and dismantling, and no detailed instructions are given for these processes.

During on-site construction, the formwork should be made and assembled well, but in practice, the construction personnel cannot make and assemble them very precisely, so the formwork often has deformation, open joints and other problems, which leads to deformation, pockmarking or honeycomb of some concrete members, so the construction unit must ensure that the concrete members meet the requirements of strength performance and avoid the deformation problems caused by poor construction process and damage problems.

　　When mixing concrete, the mixing time will also affect its quality, if the mixing time is not enough, it will lead to the failure of the cement to fully occur the heat of hydration reaction, and some constructors do not follow the requirements of the ingredients, which directly affects the strength of the concrete after molding, concrete pouring must do a good job of pounding, if the pounding is not dense enough or the pounding bar is not inserted deep enough, will lead to concrete components The concrete must be properly pounded.

When demoulding the concrete after forming, the work must be meticulous, but some construction units start demoulding without reaching the demoulding time and strength in order to catch up with the schedule, which reduces the strength of the concrete components. In the maintenance of concrete, you need to control the temperature and humidity of the surrounding environment, in the colder weather, if you do not do a good job in the maintenance of concrete components, will lead to more cracks in the concrete components. If the concrete members do not meet the strength requirements and heavier objects are placed on the concrete members, it will lead to larger loads on the concrete members in the early stage, thus increasing the probability of cracks.

　　2 Measures for quality control management of concrete construction in housing construction

　　In the housing construction project, the construction unit needs to strengthen the quality control, develop an effective management plan, the necessary constraints on the construction personnel, so as to ensure the quality of the construction of housing buildings, the following author introduces the common quality control management measures one by one.

　　2.1 Control the quality of raw materials

　　In the housing construction project, the construction unit needs to do a good job in the preservation and management of raw materials, in the transport of concrete and other materials, must reduce the transport distance, but also according to the site conditions, the mixing process to adjust the mixing time and control the mixing ratio of ingredients, but also add the right amount of admixtures.

Cement in concrete plays a role in hydration and condensation, the strength and volume stability of concrete has a decisive impact on the selection of suitable cement should be compared with the test, selected on merit. The fineness modulus and mud content of fine aggregates are the index parameters for the assessment of their quality, which has a great impact on the quality of concrete mixing.

Coarse aggregate to consider the rationality of its gradation, to ensure that the selected coarse aggregate gradation continuous, it is necessary to conduct experimental studies. The water used for mixing concrete cannot contain substances that affect the process of hydration reaction of concrete and the strength of concrete, and the water quality needs to be tested before concrete mixing and can only be mixed after passing.

Materials are the basis for controlling the quality of concrete construction. Raw materials should be strictly quality control, for unqualified, expired raw materials are not allowed to enter the construction site. The quality of materials should be tested again during the construction process, and substandard concrete materials should not be used.

　　2.2 Strictly control the technical points of construction

　　Formwork construction structure design should be reasonable, the lower bracket should be both stable and deformation resistance, mold removal should grasp the time of casting concrete forming strength, do not remove the mold too early. The concrete pouring process should be carried out under the premise of clear arrangement of reinforcement in the pouring part, and the pouring method may depend on the situation, and should be changed to the manual inserting brazing method for pounding in the dense part of reinforcement arrangement of the member.

In the pouring process must prevent the occurrence of segregation, pounding concrete should be dense, uniform, moderate, and strictly control the spacing of pounding, pounding must ensure that the surface of the elements out of the pulp, stopping time shall not exceed the initial setting time of cast-in-place concrete, if more than the initial setting time, it must be reserved for construction joints.

Early maintenance of cast-in-place concrete elements must be in place to maintain the appropriate ambient temperature and humidity. In the case of special environment and poor conditions, consider the option of using methods such as covering moisturized concrete elements for maintenance work. According to the reasonable mix ratio construction, firstly, the moisture content of sand and stone should be measured in time, and the design mix ratio should be converted into the construction mix ratio. Secondly, use the weight ratio, not the volume ratio, and finally, check in time whether the raw materials match with the raw materials at design.

　　Conclusion

　　Through the analysis of this paper, it can be seen that there are more problems in the construction of concrete for housing buildings, which can be roughly divided into two aspects of raw materials and construction techniques. In order to improve the quality of construction, construction units need to understand the reasons for the appearance of common quality problems, so as to develop effective management measures to reduce the probability of quality problems.

Concrete is a common construction material for building projects, it is a mixed material, first of all, you need to do a good job in the proportion of raw materials, but also optimize the construction process to ensure that the strength of concrete components up to standard. The rationality of the concrete construction process has a direct impact on the construction quality of the whole project, if there are safety hazards in the construction, it will threaten the life and property safety of the owner, and will also have a negative impact on the reputation of the construction unit again.

Therefore, the relevant building construction units must pay attention to the mastery of concrete construction technology, and constantly summarize and analyze in order to improve their own capabilities, so as to promote the overall development and progress of the construction industry.