The development of science and technology has laid a good foundation for the construction construction of water conservancy projects, and with the continuous improvement of the level of construction technology, our society has become more stable and developed in the direction of harmony. The construction of hydraulic engineering is a basic engineering construction, about the development of China’s infrastructure, so the quality of water conservancy projects to be strict requirements, only in accordance with the construction technology for strict construction construction, in order to get further development.
This paper focuses on the construction technology that must be used in construction construction, that is, crushed concrete construction technology, a detailed analysis of how the technology is applied to the project, and can obtain satisfactory benefits.
1 Construction plan
First of all, the selection of a set of scientific construction plan is the premise of the construction of water conservancy projects. Because there are many factors that influence the construction process at the construction site, such as the environment, temperature and many other factors that can cause problems in construction, it is important to analyze the construction plan in detail and to prevent them.
At the same time, the relevant construction personnel are required to visit the field before carrying out the project and constantly adjust the construction plan to achieve the optimized effect. Especially in the construction of key areas, the adverse effects of human factors and natural factors on the project should be taken into account, combined with the environment, geology and more elements in the construction of zoning design, determine the best construction plan and engineering construction.
2 Crushed Concrete
Crushed concrete construction technology in the process of application should first be adequately prepared, especially for the selection of raw materials for construction, if the construction of improper raw materials, then the construction of water conservancy projects will cause direct damage, so we must pay attention to the quality of raw materials, strict testing, China’s relevant system has made a clear regulation of the quality of construction materials.
The main raw material composition of compacted concrete mainly contains the following categories, the specific requirements for its management are as follows.
2.1 Cement
Cement plays the most significant role in construction, and is an indispensable raw material in engineering construction. In order to ensure the strength of concrete effectively, we should start from the quality of cement and focus on its production quality and whether it has the corresponding certificate of conformity in the process of testing.
In the construction process, the cement of one manufacturer should not be replaced at will, because the cement produced by different manufacturers also has certain differences, once replaced for the strength of the structure will have a different size of impact, so the quality and supply of cement should be strictly managed.
2.2 Admixtures
The main role of admixtures in the crushed concrete is to further enhance the strength of concrete, which contains two main substances, one is limestone, the other is fly ash, appropriate admixtures in the concrete can react with cement, cementing ability can be significantly improved, because the grade of fly ash is different, so in the construction of the project by reference to the actual situation, choose the right Because of the different grades of fly ash, so in the construction of the project by referring to the actual situation, choose the appropriate materials and pay attention to ensure that the sun and rain, to ensure that the function of the admixture can be maximized.
2.3 Additives
Additives need to be deployed at the construction site according to the different construction requirements, the use of admixtures can be the nature of the concrete itself to maximize the play, and the admixture in the concrete, the external factors on the concrete strength of the interference has become significantly smaller, but it should be noted that the scientific formulation of the admixture has an important role, so the dosage in use needs to be strictly Add to control, so as to achieve a more stable construction effect.
3 Construction technology
3.1 Paving, grading and rolling technology
In the actual construction, manual and automated construction techniques are mainly used, among which paving, grading and rolling are carried out by mechanized equipment because of the large construction volume.
In order to ensure that the aggregates can be effectively concentrated together, the unloading methods that should be used are stacked and chain type, and manual methods can also be used to disperse materials in the process of local construction to ensure that the construction can be carried out in a gradual manner during the construction process.
3.2 Induced joints, transverse joints into the form of seams
In the construction of water conservancy projects, dams often use seam cutters in the construction of earth dams for slit construction, but the current application of a more widely used form of construction for the construction of induced joints, because in the process of construction often exist construction difficulties, the principle of induced joints to carry out engineering construction, you can avoid the seam is not fixed or the problems arising from the excavation of the trench.
In addition, the horizontal joints in the construction process and the construction of the induced joints have similarities, but there are also certain differences, concentrated in the setting of the horizontal joints, to pre-set four different components, this method is more suitable for manual operation, so the construction of water conservancy projects are more common.
3.3 Bedding concrete construction technology
In the past, most of the bedding concrete of crushed concrete dams were poured using normal concrete when construction was carried out, and some corresponding vertical transportation equipment was configured to carry out the relevant transportation of normal concrete, through the analysis and study of construction practice.
At this stage, when the concrete pouring construction is carried out, it is often carried out on the horizontal surface of the bedrock, followed by direct pouring, by crushing concrete instead of normal concrete, which can not only speed up the construction, but also strengthen the control of the temperature of the dam body.
3.4 Repeated Grouting System
Compacted concrete arch dams usually do not reach a stable temperature when water storage is carried out, but in order to ensure that the arch dam has a certain overall bearing capacity, it is necessary to start the corresponding grouting of the induced joints or transverse joints. However, as the temperature of the dam body decreases, the dam body will shrink, which will cause the grouting surface to stretch and cracks to appear, requiring secondary grouting.
Puding crushed concrete arch dams are generally grouted twice using two sets of pre-built grouting pipes. In the arch dam construction process, we must strengthen the analysis of the arch dam induced seam formation principle, combine the structural situation of the seam surface, pay attention to the use of repeated grouting technology, strengthen the breakthrough of the technology, effectively solve the technical problems, and realize the orderly construction of water conservancy projects.
3.5 Formwork construction technology
Usually, crushed concrete formwork are used to make the Puding arch dam up and down alternating cantilever steel formwork, the upper and lower two panels are separable, can also be alternately ascending, speed up the dam construction speed. When carrying out water conservancy construction, must strengthen the improvement and optimization of formwork construction technology, in order to realize part of the dam body crushed concrete for continuous rise at the same time, to achieve the continuous rise of the step formwork, to ensure that the overflow energy dissipation step can be realized once pouring molding.
When carrying out the Soying project, the construction technology of continuous rise in blocks is adopted, and its design is in line with the characteristics of continuous pouring, which can realize the continuous turning up of the formwork, and ensure that the step formwork can be continuously risen, and use the way of continuous rise in blocks of flat layers to carry out the relevant pouring of the dam crushed concrete, and realize the record of continuous rise of 31 meters for the main dam. For more complex dam body shape and curvature changes, the use of seam construction method can be used to adjust the continuous climbing formwork to achieve rapid construction of the dam body.
Conclusion
The study of crushed concrete technology can be found that the crushed concrete technology can ensure that the concrete dam body can be balanced, there can be effective savings in human and material costs, is a positive role in the use of resources for the construction of water conservancy projects.
However, it is worth noting that although the advantages of crushed concrete construction of dams are obvious, but the technology is not applicable to any water conservancy projects, the construction plan for the dam should be developed according to the specific circumstances of the construction environment, in order to ensure the practicality and scientific nature of the construction technology.