JP4325754B2 - Concrete for building seaweed beds and breeding blocks using the same - Google Patents

Description

  The present invention relates to a concrete for building seaweed beds for growing seaweeds such as kelp, and a growth block using the same.

  Conventionally, concrete products such as natural stones and concrete blocks have been used as a substrate for growing seaweeds such as kelp.

  However, many seaweed beds made of these materials have poor aging effects and have a problem of low growth efficiency. “Aging effect” refers to the time-dependent establishment efficiency of the seaweed bed material introduced into the sea. In natural stones and concrete blocks, seaweeds have become poor over time, which is said to have low aging effects.

Therefore, an epidermal substrate using a shell or the like has been proposed. For example, there exists a thing like patent document 1. FIG.
Japanese Patent Laid-Open No. 5-192048

  Patent Document 1 is made of concrete using shells instead of aggregates, and casts ready-mixed concrete into a mold or the like to be used after curing, or is used by fixing the shells to the surface of the molded body with cement or adhesive. To do. This concrete has almost the same appearance as conventional general concrete, has a poor aged effect as a seaweed bed, and has a problem that it is difficult to increase the surface area of the substrate due to voids and irregularities caused by shells.

  This is considered to be due to the fact that the mix of concrete is almost the same as that of general concrete. That is, in the case of almost the same as general concrete, it is rather necessary to maintain the strength of the concrete that the porosity is low and the compressive strength is large. However, when such concrete is used for seaweed algae, it is renewed. It is unsuitable due to its small nature. “Renewability” refers to the property of allowing a new substrate surface to appear.

  As a method for collecting seaweeds such as kelp, there is a method in which seaweeds are entangled and peeled off with a rod-shaped collecting tool having a bifurcated tip. At this time, fragments of the epiphytic substrate adhere to the roots of seaweeds such as kelp and peel off. As a result, a new substrate surface appears, but seaweed spores such as kombu prefer a new substrate surface, so that they grow again and form a seaweed bed.

  If the structure is almost the same as that of general concrete as before, the surface of the concrete is hard, so when harvesting useful seaweeds such as kelp or in the stormy season in winter, it often breaks from the stem part, leaving only the roots. End up. For this reason, it takes a certain amount of time for the roots to decay, and the breeding season (around October to December) is completed without attaching new kelp spores (spores). In this case, since spores such as other seaweeds are attached instead, they are replaced with miscellaneous seaweeds and lime algae and cannot be propagated.

  In addition, in order to expose the shell on the surface of the concrete, in the case of Patent Document 1, it has to be washed out with water or stuck to the shell in an uncured state, and there is a drawback that it takes time and effort. .

  The object of the present invention is to solve the above problems and increase the proliferation efficiency of seaweeds such as kelp. Other objects of the present invention will be apparent from the following description.

In order to achieve the above object, the concrete for constructing a seaweed bed according to the present invention comprises mortar and shells, and the mixing ratio (S / C) of sand S to cement C composing the mortar is within a range of about 1 to 1.25. And the blending ratio of water W to cement C (W / C) is within the range of about 52.5% to 62.5%, and the weight of the mortar used relative to the weight of shell There is a value in the range of about 80% of to 100%, and the porosity is characterized in that it is a value within a range of around 35% of to 40%.
Further, the shell is crushed.
The shell is not crushed.
The shell is a mixture of crushed and uncrushed shells.
In addition, the above-mentioned shells are characterized by being piled up for a certain period.
In addition, the growth block according to the present invention is characterized in that the above-mentioned concrete for building algae beds is used as a substrate for the growth of seaweeds.

  According to the concrete for algae bed construction according to the present invention and the growth block using the same, the mixing ratio of sand S to cement C (S / C) is about the same amount or about 1/4 as much as the mixing ratio of mortar. In addition, since the mixing ratio (W / C) of water W to cement C is set to about 52.5% to 62.5%, the shell can be attached with an appropriate force. Thereby, at the time of harvesting seaweeds, the shell of the surface layer portion to which the seaweeds are attached can be peeled off together with the roots of the seaweeds. Therefore, since the renewability of an epiphytic substrate is obtained, it has the effect of increasing the growth efficiency of seaweeds.

  Moreover, since the use weight of the mortar with respect to the use weight of the shell is about 80% to 100% with respect to the use amount (attachment rate) of the mortar, the compressive strength and porosity of the concrete can be adjusted. The rate can be optimized. As a result, the surface area of the growth substrate becomes larger than it appears, and the growth area can be increased. Therefore, this also increases the growth efficiency of seaweeds.

  Next, the seaweed building concrete 1 according to the present invention and the growth block 11 using the same will be described in more detail with reference to the drawings showing embodiments. For convenience, portions having the same function are denoted by the same reference numerals and description thereof is omitted.

  First, regarding failure examples, seashells were pasted in a state where the mortar had not hardened, and the seaweed building construction concrete 1 was made, but it took too much time for pasting, and there was no on-site workability described later. Next, I tried to fix the shell by using a solidifying agent, but the amount of shells etc. used was small, it could not be mixed well with the solidifying agent, it took a lot of work, and there was variation in strength and construction management However, it was not practical because the solidifying agent was expensive. Next, I tried to form a mortar film by immersing a shell filled in a box made of wire mesh in a container containing mortar, but the mortar film that covers the shell according to the size of the mesh of the metal mesh and the time to immerse the shell However, the construction of the mortar residue after the use of the wire mesh and the method of transporting the shell-growth substrate immersed in the mortar were problematic. Next, I tried to make a mesh base material by filling a shell and spraying the solidifying agent, but the amount and time of the solidifying agent spraying, grasping the optimal mesh size of the wire mesh, the scattering of the solidifying agent by the spraying work It was not suitable for on-site construction due to reasons such as selecting the production site in terms of the point, residual treatment of the solidifying agent, price increase due to the trouble of spraying, and difficulty in grasping the strength characteristics. Therefore, as described in detail below, the present invention has attempted to improve mortar.

  The seaweed bed building concrete 1 according to the present invention is manufactured by making a predetermined mortar, mixing crushed or / and crushed scallop shells therein, and stirring. The mortar has a mixing ratio of sand S to cement C (S / C) of 1: 1 to 1.25, and a mixing ratio of water W to cement C (water cement ratio W / C) of 52.5% to 62. .5%. The use weight of the mortar with respect to the use weight of the shell is 80% to 100%. For example, the shells that have been piled for more than one year are used.

  The blending ratio of mortar and the amount of mortar used (attachment rate) are based on the following experimental results.

  First, Table 1 shows the results of a mortar formulation test. As a result of changing the water cement ratio (W / C) and measuring the flow value (softness of the mortar) and the compressive strength, the flow value and the compressive strength decrease as the water cement ratio (W / C) increases. Since the water cement ratio (W / C) is the weight mixing ratio of water and cement, the higher the value, the more the mortar becomes watery and the fluidity increases, and the cement content decreases, so the strength also decreases. On the other hand, when the water cement ratio (W / C) is lowered, the mortar becomes solid, the fluidity decreases, and the cement content increases, so that the strength is improved. From the blending test results, the graph of FIG. 1 was obtained for the relationship between the water cement ratio (W / C) and the flow value, and the graph of FIG. 2 was obtained for the relationship between the water cement ratio (W / C) and the compressive strength.

  Based on the flow value and compressive strength obtained from the mortar blending test results, a concrete blending test according to the present invention is performed. When the shell is put into the mortar and kneaded, the water cement ratio (W / C) is assumed to be 52.5%, 57.5%, 62.5% assuming the adhesion amount and viscosity of the mortar attached to the shell. , 67.5%, and 72.5%. In the blending test of the present concrete, the blending ratio S / C of the mortar was also changed, and the adhesion rate, porosity, and compressive strength of the mortar adhered to the shell were measured. The results of this blending test are shown in Table 2.

  The graphs of FIGS. 3 and 4 summarize changes in the properties of the concrete of the present application when the blending conditions shown in Table 2 are changed. Under the above blending conditions, as can be seen from these graphs, the porosity is increased when the mortar is hardened, and the porosity is decreased when the mortar is softened.

  The fluctuation factors of the compressive strength of concrete include the amount of mortar, the particle size of shells, etc., and it was found that the concrete of the present invention is not controlled by the water cement ratio W / C, unlike ordinary concrete. The amount of mortar and the particle diameter of the shell are closely related to the porosity (see FIG. 4). There is also a close relationship between the compressive strength and the porosity (FIG. 3). It can be considered that the compressive strength can be estimated to some extent by measuring the porosity, and the porosity can be adjusted.

  Further, as shown in FIG. 5, when the water cement ratio W / C is increased, the thickness of the mortar attached to the shell is reduced, and when the water cement ratio (W / C) is decreased, the thickness of the mortar attached to the shell is increased. The mortar mixing ratio S / C shows the opposite tendency.

  Table 3 shows the results obtained by selecting the most excellent concrete blending from these blending results.

From Table 3, concrete 1 of the present application consists of cement, sand, water, crushed and / or crushed shell, the amount of shell used is 900 kg / m ³ , mortar compounding ratio S / C (sand S and cement C (Mixing ratio) 1: 1 to 1: 1.25, water cement ratio W / C (weight mixing ratio of water W and cement C) 52.5% to 62.5%, adhesion rate (the mortar ratio relative to the shell use weight) Use weight) 80% to 100%. At this time, the compressive strength of the concrete is 2.15 N / mm ^{2 on} average, and the bending strength is about ½ of the compressive strength. FIG. 6 shows the concrete 1 for creating a seaweed basin thus produced. 3 shows the basic concrete which consists of concrete of a normal composition.

  Here, each upper limit value and lower limit value will be described with respect to the blending ratio of mortar and the amount of mortar (attachment rate) according to the present invention.

  First, the reason why the upper limit value of the mortar mixture ratio S / C is set to about “1.25” is as follows. When the mixing ratio S / C of the sand S to the cement C is set to 1: 1.75 or more, the amount of the sand S is larger than the amount of the cement C in the specimens of the test numbers 22 to 25 shown in Table 2. Therefore, the kneaded shell matrix concrete was in a state close to a normal concrete composition, and there was a case that almost became a concrete state as in test number 24. When the specimen in this state is placed, the renewability is lowered because the substrate strength is excessive with few voids. Therefore, since it is inappropriate to set the mortar blending ratio to “1.75 or more”, the upper limit value is set to about “1.25” having a smaller value.

  The reason why the lower limit of the mortar mixture ratio S / C is set to about “1” is as follows. The ratio of normal mortar is “1 to 1”. If this amount is below this value and the amount of cement C is relatively increased, the fluidity of the concrete decreases, and the strength of the concrete becomes excessive, so the renewability decreases. Therefore, the lower limit is set to about “1”.

  Next, the upper limit of the water cement ratio W / C is set to about “62.5%” for the following reason. When the mixing ratio of water W to cement C is set to “67.5%” or more, for example, in Test Nos. 24 and 25, the kneaded shell matrix concrete becomes water-like and the fluidity increases and is close to a normal concrete composition. Some of them were in a concrete state, as in test number 24. In addition, the shell was not well covered with mortar, and it was close to the separated state. When the specimen in this state is placed, the renewability is lowered because the substrate strength is excessive with few voids. Therefore, the upper limit value of the water cement ratio W / C is set to about “62.5%” which is smaller than “67.5%”.

The reason why the lower limit value of the water cement ratio W / C is set to about “52.5%” is as follows. From Table 2, in Exhibit Nos. 21 to 31, excluding unsuitable specimens having a mortar blending ratio of “1.75” and a water cement ratio (W / C) of “67.5%” or more, The water cement ratio W / C is “52.5%”. From Table 1, when the water cement ratio W / C “52.5%” or less is observed in the test numbers 11 to 17, the flow value “64.56 seconds” indicating the softness of the mortar at “50.0%” The compressive strength is “29.2 N / mm ² ” (7 days) and “40.1 N / mm ² ” (28 days). Therefore, the lower limit value of the water cement ratio W / C is set to about “52.5%”, which is larger than “50.0%”.

  Next, the upper limit of the mortar use weight (attachment rate) relative to the shell use weight is set to about “100%” for the following reason. From Table 2, since the adhesion rates of the test numbers 21 to 25 are all values of “130” or more, a value lower than this is considered an appropriate value.

  On the other hand, the lower limit value of the mortar use weight (attachment rate) relative to the use weight of the shell is set to about “80%” in the test numbers 30 and 31 in which the attachment rate is “70%” or less from Table 2, The covering of the mortar on the shell was thin and papasa, and the shell and the mortar were not intertwined and easily separated. Therefore, the lower limit value is considered to be an appropriate value. From these, the use weight of the mortar with respect to the use weight of the shell is set to about 80% to 100%.

  The present concrete 1 blended in this manner was not too soft in terms of viscosity in any of the mortar blending ratios of S / C and W / C, and the fluidity was not lowered so much that it showed suitability. In terms of adhesion rate, it showed the suitability to cause separation of shells and mortar.

  Next, it was verified whether or not concrete having the above blending conditions could be transported from the <1> factory to the site by a concrete mixer truck, and <2> on-site workability.

  As a result, it was confirmed that <1> could be transported and discharged by a concrete mixer truck. In this regard, it can be manufactured in a batching plant of a general ready-mixed concrete factory, shells can be stored using the same facilities as general aggregates such as stone, and mortar and shells can be mixed together. Since crushing progresses with time, voids decrease, and as a result, mixing time can be discharged in about 1 minute after putting shells in, and since flat shells are used and there are many voids, it is discharged little by little. It turns out to be desirable.

  Regarding the point <2>, it was confirmed whether or not concrete can be placed at the actual site and whether or not the seaweed can be constructed. In this regard, the concrete placement of the present application can be carried out without using a vibrator like a general concrete, and the placement can be performed simply by laying it on the formwork without stepping on the foot, thus making the construction easy. It turns out that there is. In addition, when it was verified whether the construction management of the concrete placed as a substrate for curing was possible, it was possible to perform a compressive strength test with a test piece, and to manage with a compressive strength according to the concrete construction management. understood.

  Therefore, the concrete 1 of the present application can be manufactured in a ready-mixed concrete factory and transported by a concrete mixer truck while ensuring a viscosity that can be applied on site.

  As described above, according to the concrete for constructing the seaweed bed and the growth block using the same according to this embodiment, the shell can be attached with an appropriate force by appropriately blending the mortar. At the time of harvesting, the shell of the surface layer portion to which the seaweed is attached can be peeled off together with the roots of the seaweed. Therefore, since the renewability of an epiphytic substrate is obtained, it has the effect of increasing the growth efficiency of seaweeds.

  Moreover, since the use weight of the mortar with respect to the use weight of the shell is about 80% to 100% for the use amount of the mortar, the compressive strength and the porosity of the concrete can be adjusted, and the porosity can be optimized. I can plan. As a result, the surface area of the growth substrate becomes larger than it appears, and the growth area can be increased. Therefore, this also increases the growth efficiency of seaweeds.

  Further, as described above, there is an effect that the transportation to the site and the workability at the site are good.

  Furthermore, since shells are used instead of natural stones, the resource problem of depletion of natural materials, the solution of shell processing problems as industrial waste generated about 200,000 tons per year, and its effective use are achieved simultaneously. be able to.

  FIG. 7 shows an embodiment in which the algae bed construction concrete 1 having the above composition is molded for the breeding block 11. When A is a flat cylindrical block 1A for the seaweed bed building concrete 1B, B is a block 1B having a circular cutout hole 5 at the center, and C is 12 for the seaweed bed building concrete 1 This is a case where a square columnar block 1C is used. A and B are exclusively for sandy beach area, and C is for sandy beach area and bedrock area. Reference numeral 13 denotes a basic block made of concrete having a normal composition.

When each of the above breeding blocks 11 was installed at a water depth of 5 m and a seaweed bed was created to examine the prosperity of the kelp, the average number of the growing blocks 11 according to the present invention was 168 per m ^{2 of} general stone. It was confirmed that 357 / m ² and more than doubled. This is because the growth block 11 according to the present invention has a large number of voids in the structure and has uneven undulations inside, so the seaweed settlement area (about 1.5 times that of ordinary concrete) is more than apparent. Because there are many.

  The present invention is not limited to the embodiment described above. For example, the shell may be crushed or uncrushed, or a mixture of both. Moreover, shells other than scallops can be used as the shells to be used. Moreover, the sand S which comprises mortar can use not only land sand but shellfish sand. The shape and size of the growth block can be designed according to the conditions of the seaweed beds. In addition, examples of seaweeds other than kelp include gagome, wakame, hondawala, arame, and scallop, and the present invention is applicable to various seaweeds.

  The invention of the present application is used particularly for a concrete for building seaweed beds for growing seaweeds such as kelp and a growth block using the same.

It is a graph which shows the relationship between the water cement ratio (W / C) and flow value of the concrete for seaweed building construction by this invention. It is a graph which shows the relationship between the water cement ratio (W / C) and the compressive strength of the concrete for seaweed formation by this invention. It is a graph which shows the relationship between the porosity and the compressive strength of the concrete for seaweed formation by this invention. It is a graph which shows the fluctuation | variation factor of the porosity of the concrete for seaweed formation by this invention. It is a graph which shows the compounding conditions and the thickness of mortar of the concrete for seaweed formation by this invention. It is a perspective view which shows embodiment of the concrete for seaweed bed construction by this invention. A is a perspective view showing one embodiment of a breeding block using the concrete for seaweed building according to the present invention, B is a perspective view showing another embodiment, and C is still another perspective view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Concrete for seaweed bed construction 1A block 1B block 1C block 3 Foundation concrete 5 Cut-out hole 11 Growth block 13 Foundation block

Claims (6)

The composition ratio (S / C) of the sand S to the cement C constituting the mortar is a value within a range of about 1 to 1.25 , and the composition ratio of the water W to the cement C (W / C) have a value in the range of about 52.5% about to 62.5%, and a value within a range for use weight to about 100% using the weight of about 80% of the mortar shell, Moreover, the concrete for seaweed bed construction characterized by the porosity being a value within a range of about 35% to about 40%.   The said seashell is crushed, and the concrete for seaweed bed construction according to claim 1 characterized by things.   2. The seaweed building concrete according to claim 1, wherein the shell is not crushed.   2. The seaweed building concrete according to claim 1, wherein the shell is a mixture of crushed and uncrushed.   2. The seaweed building concrete according to claim 1, wherein the shell is piled for a certain period.   A breeding block characterized by using the concrete for building seaweed beds according to any one of claims 1 to 5 as a substrate for growing seaweeds.

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