The construction technology of river projects in water conservancy construction is very important. Only the reasonable application of construction technology can solve the actual problems of the project, and the handling of every detail is critical. Zhongda Consulting will explain to you the construction technology of river engineering in water conservancy construction.
In water conservancy construction, river engineering is one of the most common forms of engineering structure. Through river engineering construction, flood drainage channels can be made smoother to ensure the safety and reliability of the project area. Relevant practical research points out that because the river is a natural slope structure, it is often affected by sediment, water flow, geology and human factors, which often causes the bank slope to become unstable or suffer erosion damage. If the situation is critical, it may even cause a collapse accident on the bank slope, causing safety hazards. Therefore, during the construction process of river projects, mastering reasonable construction technology and mastering comprehensive and reliable construction techniques and methods are of great significance to improving the overall construction quality of river projects. This article focuses on systematic analysis and research on the construction technology and key implementation points of river engineering in water conservancy construction.
1. Analysis of river bank protection project construction technology
The construction conditions of a certain river bank protection project are relatively complex. The basic project is below the lowest navigable water level in the area and is subject to river water, rainwater, and Groundwater impacts. Moreover, the overall length of this bank protection project is longer and the working surface is wider. In addition, river engineering is a permanent water conservancy engineering infrastructure, so the selection of construction technology for bank protection projects is crucial. In the process of selecting the bank protection structure for this river project, the vertical bank protection method was selected. Under this shore protection method, the main components include wall, foundation, and top pressure. The main advantages are: the project structure is simple, the construction is convenient and feasible, it is less affected by ship waves, and it has a good protection effect on the land resources on both sides of the river. Specifically, the corresponding bank protection structure in this river project is shown in the figure below (see Figure 1).
Take this form of river bank protection project as an example. During the specific construction process, the technical points that need to be followed include the following aspects:
The first step is foundation pouring. During the foundation pouring construction process, it is necessary to do a good job in setting out the construction first. Since the bank protection structure in this project is upright, the difficulty of construction and laying out is relatively low. The key to ensuring the quality of setting out is to set wire points at both ends of the straight line to be staked out and around it, in areas with good visibility conditions, and to stake out the end points of the straight line with the help of theodolite, and at the same time coordinate with the layout of cross-section piles. . However, one thing that needs special attention is that for river regulation projects, since the bank protection line is difficult to maintain a straight state and is affected by many factors, the bank protection line mostly appears as a circular curve, so this method cannot be used directly for stakeout. The recommended technical measures are: use theodolite to set out by declination processing. During this period, the starting edge is set as the straight line to be placed, and the direction of the tangent line is calculated based on the rotation angle. Then the excavation work for the cofferdam structure needs to be done. In the excavation of the cofferdam structure, the main body of the excavation includes the upper soil mass and the foundation trench. During the excavation process, it is necessary to strictly control the excavation slope ratio, and arrange for dedicated personnel to regularly measure key parameters such as the internal slope ratio and external slope ratio of the cofferdam structure to evaluate the excavation quality in a timely manner. On this basis, it is also necessary to do a good job in drainage treatment of the foundation pit. This work is of great significance in the excavation of the lower earthwork of the cofferdam structure. In addition to paying attention to the elimination of groundwater at the construction site, it is also necessary to eliminate the influence of sewer pipes, atmospheric precipitation and other factors to the greatest extent. Therefore, a comprehensive selection can be made between the open ditch drainage scheme and the well point drainage scheme based on the actual conditions of the bank protection project. After the above operations are completed, foundation pouring operations can be carried out. The pouring stage requires a dedicated person to strictly control the quality indicators of the pouring materials, and conduct strict calculations and tests on the mix ratio of the raw concrete materials to ensure that they meet the design requirements.
The second step is to build the wall. During the wall masonry construction process, it is first necessary to do a good job in erection work. The main operating technology is: using angle iron as the basic raw material to form an L-shaped sample frame. During this period, the slope ratio of the sample frame should be consistent with the slope of the front wall corresponding to the bank protection project. Moreover, after the masonry work is completed, the sample frame needs to be dismantled in time. Then, the masonry work on the wall needs to be carried out. For river engineering in a general sense, the thickness of a single-layer wall structure ranges from 0.4 to 0.5m. During masonry construction, a leveling layer of a certain thickness is required for each layer of wall. The setting range of the leveling layer is recommended to be the area near the top of the wall near the top pressure. The reserved thickness of the leveling layer should be controlled to 0.15m at most. Before building the wall, you first need to pre-pave a layer of mortar on the bottom of the wall. Follow the basic principle of facing the small side up and the wide side down, and gradually complete the placement of the stones. Each construction section of the bank protection project needs to set up a settlement joint. The setting plan is: vertical direction, bottom up, from the foundation to the wall. The overall width is about 1.5cm. During this period, the verticality of the settlement joint needs to be strictly controlled. Within the range of ±1.0cm.
The third step is topping pouring. In the process of capping pouring construction, the most commonly used control raw material is concrete precast blocks. Generally speaking, the width of precast concrete blocks is about 20.0cm. Usually, after leveling the masonry wall, the precast concrete blocks are placed directly on both sides of the settlement joint.
In order to ensure the scientific and reasonable placement of the prefabricated blocks, it is necessary to use theodolite to reasonably control the positions of the front and rear ends of the prefabricated blocks. In the same way, a level is used to control the positions of the upper and lower ends of the prefabricated blocks. After the top pouring, bolts are used to fix the formwork. The comprehensive implementation of the above measures makes the final appearance of the entire bank protection project straighter and smoother.
2. Analysis of river slope protection engineering construction technology
In the implementation process of river engineering construction operations, river management is one of the crucial links. Especially for our country, affected by serious water and soil erosion problems, how to ensure the safety and stability of bank slopes to the greatest extent requires special attention to the construction and operation of river management projects. Generally speaking, the slope protection technology adopted in river management is lining construction technology. Under this construction plan, the natural form formed by the rational road itself is ignored. Although the construction is relatively convenient and the planning difficulty is low, the capital investment is quite large, and the river lining has obvious closing characteristics, which has a negative impact on the natural environment of the area where the river is located. Extremely adverse effects. Therefore, in the process of river management, relevant research recommends the rational application of high-pressure jet anti-seepage wall construction technology to ensure the effectiveness of river construction (the specific structure is shown in Figure 2 below). The implementation points of this technology can be summarized as follows:
Take this form of river slope protection project as an example. During the specific construction process, the technical points that need to be followed include the following aspects:
< p>First of all, the construction holes need to be reasonably arranged. Generally speaking, control piles need to be introduced outside the axis every 20 holes so that the quality of hole position approval during the construction process can be guaranteed. At the same time, each hole position during on-site construction needs to be clearly marked to indicate the specific sequence of the hole positions. Secondly, after the hole layout is completed, the drilling rig needs to be arranged to enter the construction site. Especially during the installation of on-site drilling tools, it is necessary to ensure that the structure is stable, and the horizontal and vertical axes of the frame, machine table, and vertical axes should be kept vertical. Secondly, drilling and final hole operations need to be performed. During the drilling process, the boreholes are required to be drilled through the mud retaining wall. The mud specific gravity is controlled to a standard of 1.1 to 1.25t/m3, and the aperture control standard is 130.0mm. Exploration holes should be set at intervals of 20.0m, and good preparations should also be made. Stratified sampling works, braided into a histogram. If the information collected from the exploration hole is different from the design, the exploration personnel and designers must jointly inspect the core. The drilling process should be well documented, including hole location, hole diameter, hole number, various stratum depths, and the drilling process, so that abnormal problems can be discovered in a timely manner. After the deep hole drilling meets the construction standards, mud needs to be poured in advance and the hole elimination duration is 30.0 minutes to minimize the sedimentation of slag in the hole and ensure that the insertion depth of the high-pressure injection equipment meets the requirements.Finally, high-pressure injection and reinjection operations are required. During the spraying process, the spraying direction needs to be determined in advance. According to the requirements for spraying water, mud, air, etc. in the construction design, the high nozzle can be raised only when the grouting standard of the orifice is 1.355t/m3. The spraying is completed at one time and must not be interrupted. If there is a mechanical failure, it should be dealt with immediately. If the processing time exceeds 20rain, the high nozzle should be lowered by 0.5m before spraying again. After the injection is completed, reinjection operations need to be carried out in time. During refilling, ensure that the pipeline is smooth and clean.
3. Conclusion
A large amount of engineering construction experience shows that: as one of the most typical water conservancy buildings, bank protection projects have relatively simple overall structures, but the construction conditions are relatively complex. During the construction of the bank protection project, it is necessary to carry out operations in strict accordance with the specifications and design requirements, and systematically control the construction quality of each key link and supply and demand, so that the bank protection project can be completed with high quality and take into account the beautiful appearance and improve the bank protection project. social and economic benefits.
For more information about engineering/service/purchasing tender document writing and production to improve the bid winning rate, you can click on the official website customer service at the bottom for free consultation: /#/?source=bdzd