TWI457488B - A caudal - type breakwater with a circular arc - Google Patents

Description

Caisson breakwater with arc-shaped wave-eliminating cabin

The invention relates to a breakwater structure, in particular to a caisson type breakwater with a circular arc elimination chamber.

At present, most of the breakwaters or seawalls within 10m of the water depth in Taiwan use the structure of the riprap type, and the enlarged blocks and concrete dampers must be thrown. However, this method produces the water rights of the coastal landscape and the people. The negative impact is often criticized by environmentalists. Due to the difficulty and cost of the mining and transportation of the stone in the island of Taiwan, most of the current block stones in the harbor project are imported from mainland China. However, with the rising oil prices, the shipping costs are rising, plus the mainland. The regional economy continues to grow and environmental awareness is gradually rising. In the future, the control of block stone mining and export will become more and more strict, which will lead to the increasing monotony of block stone export. Therefore, the Taiwan harbor engineering community must propose countermeasures against this point. Most of the breakwaters in the deeper seas use the traditional caisson composite levee structure. The caisson is formed by the bottom plate, the closed upright outer wall and the inner bulkhead. The caisson is dragged and lowered to the fixed point and the inlet valve is opened. Into the water, and then gradually sink to the bottom of the seabed, then backfill the sand and gravel inside the caisson, and cast the capped concrete, and then apply to the embankment and the chest wall. The caisson composite embankment usually resists the waves by its own weight and the friction of the bottom plate to avoid the occurrence of overturning and sliding damage. However, the strong typhoon wave will still cause great shock wave pressure on the vertical outer wall of the caisson, and at the same time cause the erosion of the embankment to be lost. Therefore, the size of the caisson must be large enough to resist the typhoon wave, and when the water depth is shallow, The cost of the caisson composite levee is higher than that of the riprap.

Although the harbor project has obvious regional characteristics regardless of design conditions (waves, tides, currents, geology, earthquakes, etc.) or construction conditions (obtainment of construction materials, construction equipment, construction technology, etc.), the existing breakwaters are To ensure that it can withstand the strong wave forces of sudden events such as typhoons and maintain a long service life, it is usually necessary to set a large caisson and use a wave block to reduce the wave energy, but this will increase the amount of steel and concrete. The cost of the project, and the use of the wave block, hinders the aesthetics of the landscape. Therefore, there is still a need to develop other types of breakwaters.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a caisson type breakwater having a wave eliminator which is capable of effectively reducing wave reflectivity and reducing wave energy to reduce the force of waves on the breakwater.

The invention is suitable for use as a seawall and a breakwater structure in a coastal area, thereby achieving the purpose of protecting the port. The sunken-type breakwater with a circular-faced wave-eliminating cabin comprises a combined wave-blocking body unit facing the sea side, and A caisson body unit facing the land side.

The wave eliminator body unit includes a front wall defining a anechoic chamber, a bulkhead wall spaced from the front wall, and two side walls connected between the front wall and the bulkhead wall, the front The wall has an upstanding wall portion extending upward from the bottom edge in the upright direction and terminating at a first turning boundary line, a circular arc wall portion extending upward from the first turning boundary line of the upright wall portion and facing the partition wall And a plurality of upper openings that are spaced apart from the arcuate surface wall portion and communicate with the anechoic chamber, the length of the upper openings being the arcuate wall portion along the upper and lower sides The length of the direction is 50%~60%, the width of each upper opening is between 1.0 and 1.5 meters, and the total width of all the upper openings is 50%~60% of the total width of the front wall, wherein The arcuate wall portion of the front wall of the wave-eliminating body unit terminates in a second turning boundary line spaced from the partition wall, and the front wall further has a second turning boundary line upward in the upright direction An extended chest wall portion that cooperates with the partition wall and the two side walls to define a top opening.

The caisson body unit and the wave eliminator body unit are combined by a bulkhead wall.

The present invention has the beneficial effects of forming a cabin space between the front wall and the bulkhead wall by providing an evanescent chamber in the wave-eliminating body unit and providing the upper opening in the front wall of the sea surface. Therefore, when the wave reaches the upright wall portion and the arcuate wall portion, part of the water body is reflected by the wall surface, and part of the water body enters or falls down into the anechoic chamber through the upper opening, thereby causing wave wave waveform. A phase difference is generated before and after the front wall, and a turbulent energy loss effect occurs in the anechoic chamber, thereby effectively reducing wave energy, reducing wave reflectivity, and thereby reducing the effect of wave force on the breakwater, since the design can reduce The amount of steel and concrete can be avoided and the use of wave-eliminating blocks can be avoided. Therefore, it also has the characteristics of reducing the cost of raw materials and avoiding damage to the coastal landscape.

The above and other technical contents, features and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments.

Referring to Figures 1, 2 and 3, a preferred embodiment of the breakwater 2 of the present invention is suitable for use on the shore to provide reduced wave energy and wave pressure. The purpose of the force, which in turn achieves the purpose of protecting the port, comprises a wave-blocking body unit 3 facing the sea side and a caisson body unit 4 facing the land side.

The wave eliminator body unit 3 includes a front wall 31 adjacent to the sea side that defines a anechoic chamber 30, a bulkhead wall 32 spaced from the front wall 31, and two connected to the front wall 31 and the The side wall 33 between the bulkhead walls 32 (the preferred embodiment is shown in FIG. 1 for facilitating observation of the internal structure of the wave-eliminating body unit 3, and the side wall 33 of the other side is taken away, so in the drawing The wave-eliminating main unit 3 only shows one side wall 33), a bottom plate 34 which cooperates with the front wall 31, the partition wall 32 and the two side walls 33 to define the bottom plate 34 of the anechoic chamber 30, and a plurality of The anechoic chamber 30 is deposited on the bottom plate 34 for assisting in increasing the overall stability of the breakwater 2 by weighting stones 35. The number of the weight increasing stones 35 can be adjusted according to the environmental conditions such as the wave, the tide level, the current, the geological and the earthquake, and the stability of the breakwater 2 at the place where the breakwater 2 is installed.

Preferably, the front wall 31 has an upright wall portion 311 extending from a bottom edge 312 in the upright direction Z and ending at a first turning boundary line 313, and a first turning boundary line 313 from the upright wall portion 311. An arcuate surface wall portion 314 extending upwardly toward the partition wall 32, a plurality of upper openings 315 extending through the arcuate surface wall portion 314 and communicating with the anechoic chamber 30, and a plurality of spaced intervals A lower opening 316 is formed in the upright wall portion 311 and communicates with the anechoic chamber 30. The height of the weight-increasing stone 35 placed on the bottom plate 34 is preferably not higher than the lower end edge of the lower opening 316 to prevent the lower opening 316 from being blocked and affecting its function. And maintaining the predetermined anechoic cabin 30 Space so that the turbulent energy loss effect can be smoothly generated to achieve the effect of reducing wave energy.

Further, the upper opening 315 is an elongated opening and is disposed in parallel with the circular arc surface wall portion 314 in an up and down direction I, whereby when the wave hits the circular arc surface portion 314, part of the water body is covered by the wall surface. In the reflection, part of the water body falls down through the elongated upper opening 315, so that the waveform has a phase difference before and after the arc surface wall portion 314, and a turbulent energy loss effect occurs, thereby contributing to the reduction of the wave. can. Further, the lower opening 316 is also an elongated opening and is disposed in parallel with the upright wall portion 311 in the upright direction Z. By providing the lower opening 316, the water body entering the anechoic chamber 30 via the upper opening 315 can be re-flowed, thereby avoiding the occurrence of a water level swell.

In order to obtain a better turbulent energy loss effect, and considering that the supporting force and structural strength of the front wall 31 can meet the safety specifications of the engineering practice, the opening of the upper opening 315 in the arc surface wall portion 314 The rate is preferably 25% to 36%. The preferred length a1 of the upper opening 315 is 50% to 60% of the length A1 of the circular arc surface portion 314 along the vertical direction I, and the total width value obtained by accumulating the width b1 of all the upper openings 315 is obtained. (If there are n1 upper openings 315, the total width is n1 × b1) is preferably 50% to 60% of the width B1 of the circular arc surface portion 314. In the present embodiment, the design opening width b1 of the upper opening 315 of the circular arc surface wall portion 314 is between 1.0 and 1.5 meters.

Preferably, in order to obtain a better turbulent energy loss effect and to consider that the supporting force and structural strength of the front wall 31 can meet the safety specifications of the engineering practice, the lower opening 316 is on the upright wall portion 311. The opening ratio is also 25% to 36%. If the opening ratio exceeds the upper and lower limits, the expected wave-eliminating effect may not be achieved. And the length a2 of the lower opening 316 is preferably the upright wall portion 311 is 50% to 60% of the length A2 of the upright direction Z, and accumulates the total width value obtained by the width b2 of all the lower openings 316 (if there are n2 lower openings 316, the total width is n2×b2) It is preferable that the width B2 of the upright wall portion 311 is 50% to 60%. The design opening width b2 of the lower opening 316 of the upright wall portion 311 is also between 1.0 and 1.5 meters.

It is worth mentioning that the arcuate surface wall portion 314 of the front wall 31 terminates in a second turning boundary line 317 spaced from the partition wall 32, and the front wall 31 further has a second turning boundary line 317. A chest wall portion 318 extending upwardly in the upright direction Z, the chest wall portion 318 cooperates with the partition wall 32 and the two side walls 33 to define a top opening 360. By providing the top opening 360, even within the continuous action of the larger typhoon waves, the gas and water bodies entering the anechoic chamber 30 and the interior of the anechoic chamber 30 can still be released from the top opening 360. Therefore, it is possible to prevent the gas and the water body from accumulating to form a large pressure in the anechoic chamber 30.

The caisson body unit 4 is combined with the bulkhead wall 32 of the wave-eliminating body unit 3 and includes a rear wall spaced from the bulkhead wall 32 of the wave-eliminating body unit 3 and disposed opposite to the front wall 31. 41, and a filling module 42 filled between the bulkhead wall 32 and the rear wall 41. The weight of the filling module 42 is not limited. In the embodiment, the filling module 42 is formed by filling the space between the partition wall 32 and the rear wall 41, thereby forming the filling module 42. The breakwater 2 has sufficient weight to remain stable under the action of waves.

Preferably, the upright wall portion 311 of the front wall 31 of the wave-eliminating body unit 3 is spaced apart from the bulkhead wall 32 by a first distance D1, and the upright wall portion 311 of the front wall 31 of the wave-eliminating body unit 3 is Between the rear wall 41 of the caisson main unit 4 The second distance D2 is a distance of 35% to 45 of the total width of the breakwater 2 (ie, the wall thickness of the front wall 31 + D1 + the wall thickness of the bulkhead wall + the wall thickness of the D2 + rear wall 41). %. The foregoing structural ratio is used to provide a relatively large volume for the caisson body unit 4 for providing weight, thereby ensuring that the entire structure of the breakwater 2 is stable and more resistant to strong wave forces, thereby contributing to stability. Wave clipping effect.

When the breakwater 2 is installed in the sea area, a bottom of the breakwater 2 is provided with a riprap base portion 5, and a front dam portion 319 at the bottom of the front wall 31 of the wave eliminator body unit 3 and the caisson body unit 4 respectively. A plurality of parallel base blocks 6 are respectively laid in front of the bottom of the rear wall 41 and a rear toe 411, and then two large stones of sufficient weight are placed along the surface of the riprap base 5 in front of the base blocks 6. Body 7, whereby the breakwater 2 is securely fixed at the port or coast.

Referring to Figure 4, there is shown a schematic diagram of the results obtained by using the FLOW-3D numerical simulation wave into the breakwater of the present invention according to the breakwater 2 of the present invention. As can be seen from Figure 4, when the wave 100 hits the wave-eliminating body unit 3 After the front wall 31, the waveform has a significant phase difference in front of and behind the wall of the front wall 31. It is thus explained that the structural design of the present invention can make the wave phase difference, thereby reducing the wave energy and reducing the wave. Reflectivity. It should be added that the above FLOW-3D is a fluid dynamic calculation numerical simulation system based on the three-dimensional motion equation of fluid. It was developed by Dr. CW Hirt in 1985 and developed by American Flow Science. Advanced software. FLOW-3D works with the Volume of Fluid (VOF) method to deal with free surface problems and can utilize FAVOR (Fractional Area- Volume Obstacle Representation technology to describe structures in fluids, through the validation of many related literatures, has shown that the FLOW-3D simulation system does have excellent accuracy and reliability in the analysis of fluid and structural interaction problems. Therefore, the results of the FLOW-3D simulation are sufficient to confirm that the structural design of the present invention does induce a turbulent energy loss effect.

Referring to FIG. 5, in order to simulate the wave into the breakwater according to the present invention by using the FLOW-3D value, the waveform has a phase difference before and after the wall of the front wall, and a turbulent energy loss effect occurs (block K1 in the figure). Block K2 and block K3 are shown, wherein K1, K2 and K3 are blocks with obvious turbulence, and the turbulent energy loss of K1 is the most significant, K2 is the second), and the arrow symbol in the figure indicates the water body. The flow direction, the length of the arrow indicates the flow velocity of the water molecule, and the result of FIG. 5 can also explain the structural design of the present invention, which can cause the wave to generate a phase difference after entering the breakwater and induce a turbulent energy loss effect, thereby contributing to Reduce wave energy and reduce wave reflectivity.

Referring to Fig. 6, in order to simulate the variation of the wave reflectivity of the wave into the breakwater according to the present invention by using the FLOW-3D value, wherein the yaw reflectance of the ordinate is the incident wave sharpness, and the legendary area of the upper right corner of the figure is shown. B in the block refers to the actual width inside the anechoic chamber from the inner edge of the front wall to the outer edge of the bulkhead wall, that is, D1 in Fig. 2, and the B value used in the simulation experiment is 7.56 meters. L is the wavelength, which is calculated from the period and the water depth. The L values used in this simulation experiment are 38.99 meters and 56.17 meters, respectively. The value expressed in % is the opening ratio of the front wall 31. The result shows that when the opening ratio is set within the range defined by the present invention, the greater the incident wave sharpness, the smaller the wave reflectance is. This shows that the design of the present invention can effectively reduce the wave The wave reflectance achieves the effect of reducing wave energy. Among them, the wave reflectivity refers to the ratio of the reflected wave height to the incident wave height, and the incident wave sharpness refers to the ratio of the incident wave height to the wavelength in the outer sea.

Referring to Fig. 7, in order to simulate the wave pressure of the breakwater wall of the front wall of the caisson, respectively, by using the FLOW-3D value to simulate the wave into the breakwater with the wave-eliminating cabin of the present invention and another breakwater without the wave-eliminating cabin. The change of the intensity, the ordinate is the elevation, and the abscissa is the pressure intensity acting on the upright wall. As can be seen from the results of FIG. 7, the invention has the structural design of the anechoic chamber, which can effectively reduce the wave force and make The breakwater is less susceptible to damage and helps to extend its useful life.

In summary, the present invention has the breakwater 2 of the anechoic cabin, and the following effects and advantages can be obtained, so that the object of the present invention can be achieved:

1. It is verified by the above numerical simulation results that the wave force acting on the breakwater with the anechoic cabin of the present invention can be effectively reduced. Compared with the existing breakwater, the design of the present invention can reduce the size and weight of the breakwater, and can achieve the same protection. The wave effect, by which, can reduce the amount of steel and concrete used, in addition to reducing the engineering cost, saving the amount of raw materials can also help reduce resource consumption and thus achieve energy saving and carbon reduction.

2. The breakwater 2 of the present invention can be applied to the sea area within 10 meters of water depth in addition to the wave damage in the deep sea to provide a protective function, and can replace the traditional stone dyke formed by a large number of wave-eliminating blocks. In addition to effectively reducing the use of stone and wave block to reduce the amount of resources, it can also greatly enhance the beauty of the harbor landscape, and the leisure scenery for viewing and fishing can be laid behind the top opening 360 of the breakwater 2. Auxiliary facilities( For example, the platform, the plank road, and the safety protection facility provide a hydrophilic swimming space for the public, so that the breakwater 2 of the present invention has a diversified use characteristic in addition to the wave prevention function, beautifying the landscape and providing the rest function.

3. The anechoic chamber 30 of the wave-eliminating main unit 3 on the sea side of the breakwater can be used as a habitat for marine life, and the base block 6 is laid in front of the bottom of the front wall 31, and an ecological square design can be adopted. The surface of the base 6 is provided with a groove, a concave groove or a hole to allow the seaweed and seaweed to easily multiply, and to provide a living space for adsorbing wall animals, or a space for hiding and breeding of shrimps, crabs and small marine organisms, thereby The breakwater 2 of the present invention has the meaning of marine ecological conservation.

4. Since the caisson main body unit 4 on the land side of the breakwater 2 of the present invention is formed by backfilling the sand between the partition wall 32 and the rear wall 41, the center of gravity of the entire breakwater 2 is biased toward the land. On the side, if the new land is to be backfilled on the land side of the breakwater 2, this type of structure is more effective against the backfill pressure than the conventional caisson type breakwater structure.

The above is only the preferred embodiment of the present invention, and the scope of the invention is not limited thereto, that is, the simple equivalent changes and modifications made by the scope of the invention and the description of the invention are All remain within the scope of the invention patent.

2‧‧‧ breakwater

4‧‧‧ caisson main unit

3‧‧‧Balling body unit

41‧‧‧ Back wall

30‧‧‧Destroying cabin

411‧‧‧After the toe

31‧‧‧ front wall

42‧‧‧Filling module

311‧‧‧Upright wall

5‧‧‧Rocking Foundation

312‧‧‧ bottom edge

6‧‧‧

313‧‧‧ first turning line

7‧‧‧ stone cover

314‧‧‧Arc wall

100‧‧‧ waves

315‧‧‧Open hole

Z‧‧‧Upright direction

Opening at 316‧‧

I‧‧‧Up and down direction

317‧‧‧ second turning boundary

D1‧‧‧First distance

318‧‧‧Breast wall

D2‧‧‧Second distance

319‧‧‧ Front toe

A1, A1‧‧‧ length

32‧‧‧Chamber

B1, B1‧‧‧ width

33‧‧‧ side wall

A2, A2‧‧‧ length

34‧‧‧floor

B2, B2‧‧‧ width

35‧‧‧weightening stone

K1, k2‧‧‧ blocks

360‧‧‧Top opening

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view showing a state in which one side of a breakwater having a wave eliminator of the present invention is cut off; and Fig. 2 is a side sectional view showing a wave eliminator of the preferred embodiment a case where a front wall of the main body unit has a circular arc wall portion; 3 is a front elevational view showing a case where a front wall of the wave-eliminating main unit of the preferred embodiment is provided with a plurality of upper openings and a plurality of lower openings; FIG. 4 is a schematic diagram of a wave impact result, illustrating waves. The phase difference between the waveforms before and after the front wall of the breakwater model; FIG. 5 is a schematic diagram of the results of the wave action using FLOW-3D numerical simulation, illustrating the phase difference and turbulent energy loss effect of the wave waveform; 6 is a relationship diagram using FLOW-3D numerical simulation wave action to illustrate the change of wave reflectivity after the wave enters the breakwater; and Figure 7 is a relationship diagram using FLOW-3D numerical simulation wave action. , indicating the change of the wave pressure strength of the breakwater with the wave-eliminating cabin and the breakwater without the wave-eliminating cabin.

2‧‧‧ breakwater

3‧‧‧Balling body unit

30‧‧‧Destroying cabin

31‧‧‧ front wall

311‧‧‧Upright wall

312‧‧‧ bottom edge

313‧‧‧ first turning line

314‧‧‧Arc wall

315‧‧‧Open hole

Opening at 316‧‧

317‧‧‧ second turning boundary

318‧‧‧Breast wall

319‧‧‧ Front toe

32‧‧‧Chamber

33‧‧‧ side wall

34‧‧‧floor

35‧‧‧weightening stone

360‧‧‧Top opening

4‧‧‧ caisson main unit

41‧‧‧ Back wall

411‧‧‧After the toe

42‧‧‧Filling module

5‧‧‧Rocking Foundation

6‧‧‧

7‧‧‧ stone cover

Z‧‧‧Upright direction

I‧‧‧Up and down direction

Claims (9)

A caisson type breakwater with a circular arc anechoic chamber, comprising: a wave eliminator body unit, comprising a front wall defining a anechoic chamber, a partition wall spaced apart from the front wall, and two connections a side wall between the front wall and the bulkhead wall, the front wall having an upstanding wall portion extending upward from a bottom edge in an upright direction and terminating at a first turning boundary line, a first from the upright wall portion a circular arc wall portion having a turning boundary line facing upward and facing the partition wall, and a plurality of upper openings that are spaced apart from the arcuate surface wall portion and communicate with the anechoic chamber, the upper openings The length is 50% to 60% of the length of the arcuate wall portion along the vertical direction, and the width of each of the upper openings is between 1.0 and 1.5 meters, and the total width of all the upper openings is the front wall. 50%~60% of the total width; and a caisson body unit is combined with the bulkhead wall of the wave-eliminating body unit, wherein the arc-shaped wall portion of the front wall of the wave-eliminating body unit terminates at a second turning boundary line at which the partition walls are spaced apart, and the front wall further has a second turning boundary line along the upright direction Parapet portion extending portion of the parapet to the bulkheads, forming the two side walls cooperate to define a top opening. The sunken-type breakwater with a circular-faced wave-eliminating cabin according to the first aspect of the patent application, wherein the upper openings of the front wall of the wave-eliminating body unit are elongated openings and are parallel in an up-and-down direction It is placed on the arc surface wall portion. a caisson type breakwater having an arc-shaped wave-eliminating chamber according to the second aspect of the patent application, wherein the upper opening has an opening in the arc-shaped wall portion The rate is 25% to 36%. A sunken-type breakwater having a circular-faced wave-eliminating cabin according to the first or second aspect of the invention, wherein the front wall of the wave-eliminating body unit further has a plurality of spaced-apartly spaced apart portions of the vertical wall portion And a lower opening communicating with the anechoic chamber. A caisson-type breakwater having a circular-faced wave-eliminating chamber according to claim 4, wherein the lower openings of the front wall of the wave-eliminating body unit are elongated openings and are parallel along the upright direction Set on the upright wall. The caisson-type breakwater with a circular arc-eliminating chamber according to the fifth aspect of the patent application, wherein the lower opening has an opening ratio of 25% to 36% on the upright wall portion. The caisson type breakwater having a circular arc-shaped wave-eliminating chamber according to claim 5, wherein the length of the lower opening is 50% to 60% of the length of the upright wall portion in the upright direction, The width of the opening is between 1.0 and 1.5 meters, and the total width of all the lower openings is 50% to 60% of the total width of the front wall. The caisson-type breakwater with a circular-faced wave-eliminating cabin according to the fourth aspect of the patent application, wherein the wave-eliminating body unit further comprises a front wall, a partition wall and the two side walls are combined to define the elimination a bottom plate of the wave cabin and a plurality of weight-increasing stones stacked on the floor of the wave-eliminating cabin. A caisson type breakwater having a circular arc erasing cabin according to the fourth aspect of the invention, wherein the caisson main unit comprises a compartment spaced apart from the bulkhead unit and opposite to the front wall a rear wall, the first wall of the front wall of the wave-eliminating body unit is spaced apart from the bulkhead wall by a first a distance between the upright wall portion of the front wall of the wave-eliminating body unit and the rear wall of the caisson body unit, the first distance being 35% to 45% of the total width of the breakwater, the total width of the breakwater The result is the sum of the wall thickness of the front wall, the first distance, the wall thickness of the bulkhead wall, the second distance, and the wall thickness of the back wall.