The revetment project is a part of the river regulation project, which is a systematic project involving water conservancy, water transport, industry and agriculture. The design of revetment engineering should not only respect the evolution law of river bed, but also seriously consider the requirements and interests of all parties concerned. Before the project design, economic investigation should be carried out to fully reflect the value of comprehensive management and mobilize the enthusiasm of all parties.
1, revetment works
Revetment works in the middle and lower reaches of the Yangtze River can be generally divided into two types according to the scope of application. One is mainly aimed at flood control, such as Jingjiang levee and Wuwei levee, and its source of funds is invested by the state. A kind of revetment project with the main purpose of developing and utilizing the coastline or water area, such as Xibatou revetment project on the left bank of Bafengzhou confluence section, is built to reduce the siltation of the deep-water wharf of the refinery on the right bank, and its capital source is mainly enterprise fund-raising. This paper mainly discusses the design of the latter revetment project.
In the initial stage of enterprise construction, enterprises generally do not attach importance to revetment engineering, or even regard it as an extra burden. For example, Jiangyin Chengxi Shipyard built a factory in Huangtian Port Gaotan on the right bank of Jiangyin River. At that time, the coastal water depth was stable and the harbor conditions were good, but the left bank of Jingjiang County collapsed seriously. If the riverbed widens due to bank collapse, it may affect the deep-water harbor basin on the right bank, and enterprises are reluctant to invest in the bank protection project on the left bank. The dam head revetment at the western end of Bagua Island was also invested and constructed after siltation occurred in the harbor basin of the right bank refinery. Maanshan Iron and Steel Company built a power plant on the right bank of Xiaohuangzhou in the early 1950s, and the bank collapsed after completion, which seriously affected the safety of the power plant. Maanshan Iron and Steel Co., Ltd. invested in the construction of bank foundation head and groin, riprap revetment 1 km, riprap 536,000 m', and subsidence168,000 mz. Eight years later, the situation of bank failure has not changed. The analysis data of riverbed evolution show that the bank collapse of the power plant is due to the small Huangzhoutou, which makes the Zhoutou collapse greatly, resulting in the continuous downward movement of the right bank of the right Han River. If we don't stop the collapse of Zhoutou first and only consider the power plant revetment, then the revetment section will be extended with the collapse of Xiaohuangzhou Head, and the peak point of water flow will continue to move down, which is difficult to protect. 1969- 197 1 year, Maanshan iron and steel co., ltd invested in the construction of xiaohuangzhoutou dike protection project, with a riprap of 500,000 m' and a length of 4 km, which stabilized zhoutou and controlled the bank collapse of power plant, and initially achieved the expected purpose. However, after the protection of Xiaohuangzhoutou, the riverbed cut down, and the inflow section of the left Hankou sluice developed, and the diversion ratio of the left Han River increased, which affected the stability of the right Han River. Because the bank collapse section on the left bank of the diversion area keeps moving down, the diversion point and the end of the upper deep trough keep moving down, which forms a favorable river regime for the positive drainage of the left Hanjiang River. Bank protection (including reinforcement) from Taiyanghekou to Xinhekou section on the left bank of distributary area 1973- 1977, with riprap of 664,000 m'. The riprap of the above three sections of revetment works is 6.5438+700,000 m', which has stabilized the river regime and achieved good engineering results. If Masteel can design the revetment project from the whole river section in the early stage of the project, it can achieve the same engineering effect with less engineering investment. In order to improve the silting environment of the coal terminal, Hechang Hebi Power Plant invested in the revetment project of Hechang Zhoutou, but failed to invest in the revetment project of the bank collapse section of the sand trough estuary on the left bank of the upstream diversion area in time, which delayed the opportunity and reduced the diversion ratio of right Korea (main Korea) from 52% to 48%. As a result, more engineering measures need to be taken to stabilize the dominant position of Right Korea and ensure the complete operation of the right Korean port basin and water intake. From the above engineering practice, it is clear that the design of revetment engineering serving for river development and utilization must be guided by the characteristics and laws of river bed evolution, follow the laws and respect science, and work out the main regulation scheme of the whole river section. River resources are priceless, but the use of these resources must pay a price. Although these revetment projects were put forward because of the development and utilization of coastline, they undoubtedly brought great benefits to flood control. We should make full use of this advantage to provide the greatest convenience for its engineering realization.
In the implementation of the project, we should strictly respect science and have a sense of urgency when determining the construction section, project schedule and engineering quantity. At the end of 1970s, due to insufficient funds, small quantities and short berm length, the berm project failed to achieve the design effect, but was copied by the flood, and the berm project completely lost its function. The protection project of Xiaohuangzhoutou is also due to insufficient funds. In the first year, there was a gap in the revetment design, but in the flood season, it was copied into the blank section of the revetment by water. In the second year, although the whole revetment project was designed, due to the slow progress of the project, the riprap project could not be completed as designed before the flood came, and 80% of riprap fell into the river in a flood season. In the third year, the project started early and was constructed in strict accordance with the design. So far, the project is still playing a good engineering effect. It can be seen that in the area with serious bank collapse, the design of revetment engineering cannot leave gaps, and it must be completed in one go before the flood season.
At the experience exchange meeting of bank protection engineering in the middle and lower reaches of the Yangtze River, many people gave up groin bank protection and gave priority to smooth bank protection. The main reason is that groins interfere with the flow pattern, strengthen the local erosion of the river bed by the water flow, make the river bed cut down, and lead to new unstable factors. Dante dam sometimes plays a good role in the comprehensive management project of shoreline utilization or smooth navigation channel. For example, the Fenhan River regulation project in Xiaotangzhou, Xijiang River, has built 45 groins on both sides of the 30-kilometer-long river. These groins are either built on the beach or in inverted sleeves, which play a role in stabilizing the channel. The engineering practice in Xiaotangzhou has achieved good engineering results. Therefore, the designer should analyze the position of the project in the river and its relationship with the sediment-laden flow according to the service object of the project, and determine the best project form and project scheme.
2, river dangerous control technology
2. 1 new technology of risk protection
2. 1. 1 interlocking concrete slab protection
In order to strengthen the integrity, impact resistance and wind and wave resistance of concrete slope protection, interlocking concrete slabs can be used as protective measures, that is, prefabricated interlocking concrete slabs are connected with each other to form a flexible row, which can not only resist impact, protect the foundation, but also adapt to deformation. Strong hinge interlocking allows the plate to move to some extent to adapt to the deformation of the foundation. This plate can be laid on the slope of 1: 2 without any support. Non-woven geotextile is laid at the bottom of the board to prevent the loss of foundation soil. The special structure of the surface layer can absorb the motion energy of waves and currents. This new structure has been applied in Yongding River.
2. 1.2 geotextile bag protection
Geotechnical formwork bag is a large-area continuous bag-like material made of upper and lower layers of geotextile. The formwork bag is filled with concrete or cement mortar, and the protective formwork bag concrete slope protection is formed after the filling material is solidified. Geotextile bag protection technology has the advantages of strong terrain adaptability, good integrity, strong scour resistance, rapid construction, durability, reasonable price and underwater construction, and good protection effect. But at present, the biggest difficulty is the construction under the condition of deep water and rapid flow, including construction machinery, filling and sinking technology. Application of formwork bag slope protection in 65438-0987 Luanhe River Diversion Project.
2. 1.3 Cement-soil slope protection
Cement-soil has been applied abroad for decades, but it has not been well popularized in China at present. Cement-soil is a building material made of cement and soil in a certain proportion, which has the advantages of easy material acquisition, simple construction, economy and convenient maintenance.
Cement soil slope protection is required to be built on a stable bank slope. At the same time, in principle, the bank slope is required to be undisturbed soil, and the filled slope must be compacted to prevent the uneven settlement of the filled slope from causing damage. The design of cement-soil slope protection is not very complicated, but the construction quality is very important. It is necessary to strictly clear the foundation, cut slopes, mix materials, fill in layers and maintain them in time. Pay attention to the time interval between two layers of cement-soil paving, and the joint surface should be chiseled to ensure close combination. The economic benefit of cement-soil slope protection is obvious. Compared with dry masonry slope protection (30cm thick), it can save more than 60% investment.
2. 1.4 geotextile soft mattress protection
Geotextile soft mattress is a kind of anti-scour structure in the form of large cushion made of geotextile as the basic material, and most of the geotextiles used are woven geotextiles. At present, there are two kinds of soft mattress: ballast soft mattress and sand-filled pipe bag soft mattress.
2. 1.5 reinforced concrete well column diversion row
The diversion row of reinforced concrete well column is a fence-like permeable building made of reinforced concrete. For important dangerous projects, the mainstream pushes the dike, threatening the safety of the dike. The groin made of concrete diversion row can play the role of silting, beach protection and dike protection, controlling flow and weakening water potential. Reinforced concrete well column diversion row has been used in many rivers such as Hutuo River and Zhulong River in Hebei Province. It absorbs the characteristics of wickerwork's wooden stake, box dike and permeable gabion project, and is a kind of bank protection project combining soft and hard. Compared with ordinary earthwork, it has the advantages of saving labor and materials and does not need frequent maintenance. Structurally, its durability will be better than other earth-rock projects.
2. 1.6 reinforced concrete pipe pile permeable groin
The two pipe joints are firmly bonded into a whole with steel bars and sulfur cement. The main functions of reinforced concrete tubular pile permeable groins are to control and guide water flow, stabilize rivers, slow down siltation, build beaches and protect dikes. This kind of dam has simple structure, short construction period and low cost, and it is a new type of river construction that can be applied in Haihe River basin.
For more information about project/service/procurement bidding, and to improve the winning rate, please click on the bottom of official website Customer Service for free consultation:/#/? source=bdzd