CN-121473280-B - Porous coconut fiber energy dissipation unit and wave dissipation system construction method

CN121473280BCN 121473280 BCN121473280 BCN 121473280BCN-121473280-B

Abstract

The invention provides a porous coconut fiber energy dissipation unit and a wave dissipation system construction method, which belong to the technical field of hydraulic engineering of coastal engineering and ecological restoration, wherein the energy dissipation unit body is a prolate cube, steel gauze is arranged on three sides, an open pore plate is arranged on backwave side, the bottom is closed, a detachable plant upper cover is arranged on the top, and the inside is filled with coconut fibers with adjustable porosity. Backwave side concave clamping grooves can be clamped with the guide rail to achieve vertical adjustment, and T-shaped grooves and tenons on two sides can be spliced into different arrays. The plant grows the fertile plant of upper cover and builds ecological unrestrained area that disappears, and the unit reserves the sensor installation space. Physical model tests show that the effects of eliminating waves and stabilizing flow are good. The energy dissipation unit structure can be applied to the construction of various wave dissipation systems, and specific adjustment is carried out based on different scenes.

Inventors

PAN XINYING
Wei Haoqiang
LIANG BINGCHEN
CHEN JIASHU
SHI LUMING
ZHANG HONG
WANG ZHENLU
WU GUOXIANG

Assignees

中国海洋大学

Dates

Publication Date: 20260508
Application Date: 20260108

Claims (9)

1. A porous coconut fiber energy dissipation unit is characterized by comprising a prolate cube unit main body (1), wherein the wave facing side and two adjacent side walls of the unit main body (1) are steel gauze (2), a backwave side is provided with an opening plate (3), a plurality of through holes are uniformly formed in the opening plate (3), a closed bottom plate (4) is arranged at the bottom of the unit main body, and a detachable plant growing upper cover (5) is arranged at the top of the unit main body; The unit main body (1) is internally filled with a coconut fiber filling material (6), and the coconut fiber filling material (6) is arranged in a loose or semi-compaction mode, so that the internal porosity is within a reasonable range of a corresponding scene, namely, the internal porosity is within a range of 70% -85%; The unit body (1) backwave side is provided with a groove type sliding rail joint (7) for installation, and the groove type sliding rail joint is used for forming sliding connection with a convex type guide rail (8) which is pre-buried and arranged on the inner surface of the installation substrate.
2. The porous coconut fiber energy dissipation unit according to claim 1, wherein two sides of the unit main body (1) are respectively provided with a T-shaped groove structure (9 a) and a T-shaped inserting structure (9 b) which are used for realizing splicing connection with adjacent energy dissipation units and locking through bolts, fasteners or clamping pieces.
3. A porous coir energy dissipating unit according to claim 1 wherein the coir filling material (6) is comprised of bundles, flocs or blends of graded fibers, the packing density of which is adjusted by compaction to vary the damping and energy dissipation capacity within the structure.
4. A porous coir energy dissipating unit according to claim 1, wherein the upper cover (5) has a shallow basin-like structure, the inside of which can accommodate the substrate soil and plant coastal plants, and the upper cover (5) is detachably connected to the unit body (1) by means of bolts, buckles or slots.
5. A porous coconut fiber energy dissipation unit according to claim 1, wherein a sensor installation cavity (10) is reserved in the unit main body (1) for arranging wave pressure, flow rate, water quality or ecology monitoring sensors.
6. A method for constructing a wave dissipating system, characterized in that the porous coconut fiber energy dissipating unit according to any one of claims 1 to 5 is used, and the method comprises the following steps: Step 1, determining main control wave conditions of a sea area according to long-term or designed wave data of the sea area where a target revetment is located, wherein the main control wave conditions comprise a representative wave period, a wave height and a wave energy level, and the main control wave conditions are divided into a low-energy wave area, a medium-energy wave area or a strong-energy wave area according to a water area at the front of the revetment; Step 2, according to the wave conditions and the shore protection structural form determined in the step 1, fixedly mounting convex guide rails on a bank slope, a vertical shore protection, a stepped shore protection or an auxiliary structure along a preset layout direction, wherein the guide rails are fixed on a concrete foundation, a steel structure or a pile foundation member; Step 3, installing the energy dissipation unit based on the guide rail, enabling the energy dissipation unit to be in sliding connection with the guide rail, and adjusting the installation elevation and the front and rear positions of the energy dissipation unit through a limiting structure to form a continuous or sectional energy dissipation unit array; Step 4, in the low-energy wave zone, single-layer or few-layer energy dissipation units are arranged, in the medium-energy wave zone, a multi-row or staggered arrangement mode is adopted, and in the strong-energy wave zone, a multi-layer stacking or combined arrangement mode is adopted; And 5, adjusting the arrangement interval, the arrangement mode and the array combination mode of the energy dissipation units according to the wave dissipation effect required by the target bank protection to obtain a preset integral aperture ratio, and simultaneously, adjusting the filling mode and the compaction degree of the coconut fibers to enable the internal porosity of the energy dissipation units to be in different working areas.
7. The method of constructing a wave dissipating system as set forth in claim 6, wherein when the wave dissipating system is applied to a vertical dock revetment scene, the porous coir energy dissipating units are disposed along a facing wave elevation of the dock revetment, the convex guide rails are disposed along the vertical direction or the direction facing the wave, so that the plurality of energy dissipating units form a continuous or semi-continuous vertical layered array in the water depth direction, wherein the front edge of the dock is formed into a multi-stage energy dissipating region having a certain thickness by controlling the overlapping ratio or the spacing distance of the adjacent energy dissipating units in the vertical direction, and the overall aperture ratio is controlled within a range of 10% -18% and the coir filling aperture ratio is controlled within a range of 70% -75% in the array configuration, so as to enhance disturbance, seepage and reflection energy dissipation of incident waves before the dock.
8. The method of constructing a wave dissipating system according to claim 6, wherein when the wave dissipating system is applied to a pile foundation open-air breakwater scene, the porous coir energy dissipating units are disposed in a water flow passage between pile foundations on a wave side of the breakwater, in front of the pile foundations or between the pile foundations and an upper structure, and are connected with the pile foundations, cross beams or auxiliary connection members through guide rails; The arrangement direction of the energy dissipation unit array is consistent with the pile row direction or forms a preset included angle, so that the flow direction of waves is changed for many times when the waves pass through the pile foundation open area, the overall aperture ratio is controlled within 18% -30% and the coconut fiber filling porosity is controlled within 80% -85% on the array configuration, and disturbance, seepage and internal energy consumption of the waves in the inter-pile channels are enhanced on the premise of keeping the overall air permeability and water body exchange capacity of the breakwater.
9. The method of constructing a wave dissipating system according to claim 6, wherein when the wave dissipating system is applied to a stepped bank protection scene, the porous coir energy dissipating units are arranged step by step along the bank protection steps, so that the energy dissipating units located at different elevations correspond to a breaking area, a climbing area or a falling area of waves respectively; The integral aperture ratio of the energy dissipation unit array is controlled within a range of 20% -30% and the coconut fiber filling aperture ratio is controlled within a range of 80% -85% at a step position close to the water surface or mainly under the direct action of incident waves so as to slow down wave impact and promote water body exchange, and the integral aperture ratio of the energy dissipation unit array is controlled within a range of 10% -18% and the coconut fiber filling aperture ratio is controlled within a range of 70% -75% at a step position close to the bottom or concentrated in falling water flow so as to enhance the energy consumption effect on climbing water bodies and falling water flows.

Description

Porous coconut fiber energy dissipation unit and wave dissipation system construction method Technical Field The invention belongs to the technical field of hydraulic engineering for coastal engineering and ecological restoration, and particularly relates to a porous coconut fiber energy dissipation unit and a wave dissipation system construction method. Background Coastal and near-coastal areas are subjected to the combined action of complex hydrodynamic forces such as stormy waves, swells, long-period waves and the like for a long time. When waves propagate in shallow water, energy of waves is attenuated slowly, and scouring, slapping, vibration and potential resonance effects are often generated on a bank slope, a breakwater and a coastal infrastructure, so that structural safety and stability of a bank line are affected. In order to resist the adverse effects, rigid or semi-rigid structures such as a riprap dike, a gravity type concrete breakwater and a wave-absorbing block are adopted in the traditional engineering. The structure is against wave load by means of mass or section, and has a clear design theory, but the problems of large structural quantity, high construction difficulty, insufficient adaptability and large interference to the offshore ecological environment generally exist. In recent years, some researches and engineering practices have attempted to adopt a transparent or ecological structure so as to weaken reflected waves, improve local hydrodynamic environment and meet ecological requirements. For example, the prior art discloses wave-dissipating structures with a certain water permeability formed by means of cavity blocks, through-hole members, ecological bricks, etc., so as to reduce wave surface elevation and impact pressure to a certain extent. However, the above-described techniques still suffer from the following general deficiencies in use: (1) The aperture ratio is not adjustable. The existing permeable member usually determines fixed aperture ratio and hole arrangement mode in the manufacturing stage, and after installation, the overall permeability is difficult to dynamically adjust according to wave conditions, so that the problems of insufficient wave elimination or reflection enhancement and the like can occur in the sea area with large periodic variation; (2) The internal materials have limited ability to dissipate energy. The partial ecological bank protection technology introduces porous media or plant-growing base materials, but the main effects are mainly concentrated on stable surface layer slope protection or plant-growing attachment, the energy dissipation mechanism after wave incidence is underutilized, and a mature 'internal seepage energy consumption-orifice plate flow control-turbulence after penetration' multistage energy dissipation mode is not formed yet; (3) The modular underwater structure installation mode lacks adjustability. The existing structure depends on fixed anchoring, pouring base or large prefabricated foundation. Once the installation is completed, the position and the elevation of the device are difficult to adjust, and the device is not suitable for the bank slope dredging change, tide level fluctuation or maintenance requirements in the operation period; (4) The integration level of ecological functions is not high. Although ecological revetment schemes have been introduced into the vegetation modules or attached substrates, most structures still lack replaceable, maintainable, independent vegetation unit designs, nor do they form an ecological hydraulic system with synergistic vegetation layers, perturbation layers, and percolation layers. In view of the above, a novel energy dissipation unit technology with light structure, convenient and fast construction, adjustability and interchangeability, sufficient energy dissipation and remarkable ecological effect is urgently needed, so as to solve the problems of static layout, single energy dissipation mechanism, insufficient ecological fusion degree, inconvenient maintenance and the like in the prior art. Disclosure of Invention Aiming at the problems, the invention mainly aims to provide a porous coconut fiber energy dissipation unit and a wave dissipation method, which overcome the defects of the existing wave dissipation device in the aspects of adaptability, ecology and maintainability in terms of structure and method, and realize the organic combination of efficient wave dissipation and ecological restoration. Specifically, the invention aims to provide a modularized unit structure filled with natural coconut fiber materials, and a continuous and controllable multistage energy consumption mechanism is formed by step-by-step coupling of disturbance, seepage and steady flow processes of incident waves. Meanwhile, the unit realizes flexible adjustment of unit elevation and array aperture ratio through the back groove guide rail and the lateral T-shaped splicing structure, so that the unit is