JP6465297B2 - Collection pipe for groundwater drainage facility and method for preventing slime adhesion in drainage pipe for groundwater drainage facility - Google Patents

Description

  The present invention relates to a drainage pipe for groundwater drainage facilities and a method for preventing slime adhesion in a drainage pipe for groundwater drainage facilities, and is installed on a slope of a natural ground in order to prevent the occurrence of a landslide, and collects groundwater from a natural ground. The present invention relates to a technology for preventing slime from adhering in a water collecting pipe that is discharged to the surface.

  As one of the landslide countermeasure technologies, a strained groundwater catchment pipe is buried in the ground, and the groundwater contained in the ground is discharged to the ground surface through this catchment pipe, thereby reducing the groundwater level and generating landslides. Methods for suppressing are known. Landslide countermeasures using groundwater collection pipes are implemented in many areas. However, it has been confirmed that the drainage function of groundwater is reduced due to clogging of the strainer, and there is concern about the impact on the landslide prevention effect. In addition, it has been confirmed that the substance causing this clogging is a slime produced mainly by iron bacteria (iron bacteria) using iron in groundwater.

  In view of this, an apparatus has been proposed that prevents clogging by suppressing the growth of iron bacteria, which are aerobic bacteria. That is, an apparatus (for example, Patent Document 1) in which a pipe is connected to a water collecting pipe and air is prevented from entering the pipe and assembled, or an open end that is a drain end of the pipe connected to the water collecting pipe There is known a device (for example, Patent Document 2) in which the water is placed so as to be immersed under the water surface. However, in these apparatuses, a sufficient prevention effect may not be recognized.

  For this reason, until now, the inner wall of the underground water collection pipe was washed with high-pressure water, and the slime, which is a clogging substance adhering to and accumulated in the collection pipe, was removed to restore the lowered groundwater removal function. . However, cleaning with high water pressure requires regular maintenance of the groundwater collection pipe. For this reason, enormous maintenance costs have arisen due to this, and it has become an issue to develop a function maintenance management technology for groundwater catchment pipes that can be rational and reduce costs.

JP 2001-040673 A JP 2001-090094 A

  Therefore, the present invention is capable of maintaining the groundwater drainage function without requiring regular maintenance that has been conventionally required, and can reduce the maintenance cost in the groundwater drainage facility. It aims at providing the slime adhesion prevention method in the water collection pipe for groundwater drainage facilities.

  In order to achieve the above object, the invention according to claim 1 is a water collecting pipe for a groundwater drainage facility embedded in a slope of a natural ground, and is a strainer for collecting the groundwater of the natural ground. Is provided in the outer peripheral wall, and has a pipe main body provided with an outlet for draining ground water collected through the strainer at the downstream end, and inside the pipe main body through the strainer. A metal member mainly composed of magnesium that is dissolved in contact with the collected groundwater and generates electrons that suppress the oxidation of iron ions contained in the groundwater is provided with a flow path for the groundwater. It is characterized by.

  According to a second aspect of the present invention, in the water collecting pipe for the groundwater drainage facility according to the first aspect, the metal member containing magnesium as a main component is formed of a magnesium pipe that is rounded with a smaller diameter than the pipe main body. It is characterized by that.

  The invention according to claim 3 is the groundwater drainage facility water collecting pipe according to claim 1 or 2, wherein the groundwater collected through the strainer is temporarily stored near the outlet of the pipe body, An elbow pipe for draining the stored groundwater from a position above the outlet is connected to the outlet of the pipe body.

  The invention according to claim 4 is a method for preventing the adhesion of slime that induces blockage of a water collecting pipe for groundwater drainage facilities that is embedded in a slope of a natural ground, and collects groundwater from the natural ground. A metal member mainly composed of magnesium is inserted into the inside of the pipe body in which a strainer is drilled in the outer peripheral wall, and a discharge port for draining groundwater collected through the strainer is provided at the downstream end. Place and contact the groundwater collected in the pipe body via the strainer, and the electrons generated by dissolving the magnesium component contained in the metal member in the groundwater act on the iron ions contained in the groundwater. By preventing the oxidation of the iron ions, slime adhesion to the inside of the tube body is prevented.

  The invention according to claim 5 is the slime adhesion preventing method according to claim 4, wherein the metal member mainly composed of magnesium is a magnesium tube that is rounded with a smaller diameter than the tube body. To do.

  The invention according to claim 6 is the slime adhesion preventing method according to claim 4 or 5, wherein the groundwater collected through the strainer is temporarily stored near the outlet of the pipe body. In addition, an elbow pipe for draining the stored groundwater from a position higher than the outlet is connected to the outlet of the pipe body.

  The invention according to claim 7 is the slime adhesion prevention method according to any one of claims 4 to 6, wherein the iron component contained in the natural ground is prevented from eluting and flowing into the pipe body of the water collecting pipe. The iron component elution suppressing material is embedded or dispersed on the surface of the natural ground.

  This invention is as described above, and according to the invention described in claim 1, is a water collecting pipe for a groundwater drainage facility that is embedded in a slope of a natural mountain, A strainer for collecting water is drilled in the outer peripheral wall, and has a pipe main body provided with a discharge port for discharging groundwater collected through the strainer at the downstream end. A metal member composed mainly of magnesium that dissolves in contact with groundwater collected through a strainer and generates electrons that suppress the oxidation of iron ions contained in the groundwater secures the flow path of groundwater. Therefore, it is possible to suppress the oxidation of iron ions in groundwater, which causes slime generation, with a very simple configuration in which a metal member mainly composed of magnesium is disposed inside the tube body. it can. As a result, the groundwater draining function of the water collecting pipe can be maintained without requiring regular maintenance as in the prior art, and the maintenance cost can be reduced.

  According to invention of Claim 2, since the metal member which has magnesium as a main component is comprised with the magnesium pipe | tube shape | molded by the diameter smaller than the pipe | tube main body, the said water collection pipe | tube does not increase in weight, but said An effect can be produced. Moreover, the range which contacts a groundwater becomes large because a metal member is made into a tubular shape, and melt | dissolution to the groundwater of a magnesium component can be maintained over a long period of time.

  According to the invention described in claim 3, the groundwater collected through the strainer is temporarily stored in the vicinity of the discharge port of the pipe body, and the stored groundwater is drained from a position above the discharge port. Since the elbow pipe is connected to the outlet of the pipe body, it is possible to ensure sufficient time for the underground water to contact the magnesium pipe by impregnating the magnesium pipe into the ground water in the area where the ground water near the outlet is stored. it can. Thereby, dissolution of the magnesium component into the ground water and emission of electrons into the ground water can be sustained over a long period of time, and the slime adhesion preventing effect is improved. Moreover, since the range in which groundwater contacts with outside air is limited only to the vicinity of the opening of the elbow pipe, oxidation of iron ions contained in the groundwater itself is suppressed, and the slime adhesion preventing effect is further improved.

  According to the fourth aspect of the present invention, there is provided a method for preventing adhesion of slime that induces blockage of a water collecting pipe for groundwater drainage facilities that is embedded in a slope of a natural ground, wherein the groundwater of the natural ground is A metal member mainly composed of magnesium in a pipe body in which a strainer for collecting water is drilled in an outer peripheral wall and a discharge port for draining groundwater collected through the strainer is provided at an end on the downstream side. The iron ions contained in the groundwater are made to contact with the groundwater collected in the pipe body via the strainer, and the magnesium component contained in the metal member dissolves in the groundwater. This prevents the slime from adhering to the inside of the tube body by suppressing the oxidation of the iron ions, so that it is extremely easy to insert and arrange a metal member mainly composed of magnesium inside the tube body. In a way, it is possible to suppress the oxidation of the iron ions in groundwater causing slime generation. As a result, the groundwater draining function of the water collecting pipe can be maintained without requiring regular maintenance as in the prior art, and the maintenance cost can be reduced.

  According to the fifth aspect of the present invention, since the metal member mainly composed of magnesium is a magnesium tube having a smaller diameter and rounder than the tube body, a lighter magnesium tube can be used as the metal member. This reduces the burden of insertion work into the tube body. Moreover, the range which contacts a groundwater becomes large because a metal member is made into a tubular shape, and melt | dissolution to the groundwater of a magnesium component can be maintained over a long period of time.

  According to the invention described in claim 6, the groundwater collected through the strainer is temporarily stored near the outlet of the pipe body, and the stored groundwater is drained from a position above the outlet. Since the elbow pipe is connected to the discharge port of the pipe body, the magnesium pipe is impregnated in the ground water in the portion where the ground water is stored near the discharge port, and sufficient time can be secured for the ground water to contact the magnesium pipe. . Thereby, dissolution of the magnesium component into the ground water and emission of electrons into the ground water can be sustained over a long period of time, and the slime adhesion preventing effect is improved. Moreover, since the range in which groundwater contacts with outside air is limited only to the vicinity of the opening of the elbow pipe, oxidation of iron ions contained in the groundwater itself is suppressed, and the slime adhesion preventing effect is further improved.

  According to invention of Claim 7, the iron component elution inhibitor which suppresses that the iron component contained in a natural ground elutes and flows into the pipe main body of a water collection pipe is embed | buried in the surface of the said natural ground, or Since it spreads, the elution itself of iron contained in the soil can be relaxed and the inflow of iron ions into the water collecting pipe can be suppressed. Thereby, it can suppress that the density | concentration of the iron ion in groundwater increases, and the adhesion prevention effect of the slime in a water collection pipe | tube can be improved.

It is a schematic cross section which shows the whole structure of the horizontal boring to which the water collecting pipe for groundwater drainage facilities which concerns on embodiment of this invention was applied. It is a photograph which shows the slime adhesion state before the test of the horizontal boring which implemented the confirmation test of the slime adhesion prevention method same as the above. It is the photograph which shows the appearance of the slime adhesion situation to the elbow pipe hole mouth about one month after the test start same as the above, (a) the water collection pipe with the magnesium pipe inserted, (b) the collection with the aluminum pipe inserted. Water pipe, (c) is the elbow pipe hole of the water collecting pipe into which nothing is inserted. It is a photograph which shows the internal condition of an elbow pipe hole opening same as the above, (a) is a water collection pipe which inserted the magnesium pipe, (b) is a water collection pipe which inserted the aluminum pipe, (c) is a collection pipe which has nothing inserted. It is the inside situation of the elbow hole of the water pipe. It is a photograph which shows the change condition of the magnesium pipe and aluminum pipe which were inserted in the water collection pipe same as the above. It is the photograph which shows the condition of the waste_water | drain stored in the water collection pipe same as the above, (a) in the water collection pipe which inserted the magnesium pipe, (b) the waste water stored in the water collection pipe which inserted the aluminum pipe This is the situation.

  Hereinafter, a case where the water collecting pipe according to one embodiment of the present invention is applied to horizontal boring which is a groundwater draining facility will be described as an example.

  FIG. 1 is a schematic cross-sectional view showing the overall configuration of horizontal boring, which is a groundwater drainage facility. In FIG. 1, reference numeral 1 denotes a water collecting pipe. The water collecting pipe 1 is embedded below the ground water surface of the natural ground A in an inclined state with its open end facing downward. The water collecting pipe 1 has a pipe main body 2 made of a hollow cylindrical pipe, the upper end of which is closed, so that earth and sand do not enter from the upper end, and the opened lower end protrudes from the earth wall B of the natural ground A. Has been. In the length direction of the tube body 2, a plurality of strainers 3, which are holes penetrating the tube wall of the tube body 2, are formed at predetermined intervals. Therefore, since the pipe body 2 to which the strainer 3 is applied is buried in the natural ground A in a downward inclined posture from the upper end to the lower end, water is collected from the natural ground A into the pipe main body 2 via the strainer 3. The underground water 4 is led from the earth wall B to a lower discharge port opened.

  An elbow pipe E is connected to the discharge port of the pipe body 2. As shown in the figure, one end of the elbow pipe E is connected to the outlet of the pipe body 2, and the other end is a hole that opens outward at a position above the outlet. Therefore, the groundwater led to the discharge port of the pipe body 2 is temporarily stored in the vicinity of the discharge port of the pipe body 2 without being immediately drained, and when the height reaches the lower end of the hole of the elbow pipe E, It is discharged as 5.

  On the other hand, a magnesium alloy tube (magnesium tube 6) is disposed inside the tube body 2 as a metal member mainly composed of magnesium. The length and shape of the magnesium pipe 6 are not particularly limited as long as it can be disposed inside the pipe body 2. For example, ASTM standard (American Society of Testing and Materials) ), A magnesium alloy tube comprising about 3% aluminum, about 1% zinc, and about 96% magnesium can be used. As a method of fixing the magnesium tube 6 to the tube body 2, for example, a method of directly fixing to the bottom of the tube body 2 by heat welding, a method of removably fixing via a support member, or the like can be adopted. Whichever method is used, it is sufficient that a sufficient flow path for guiding the groundwater to the discharge port side of the pipe body 2 is secured.

  According to the water collecting pipe 1 configured as described above, the groundwater 4 collected inside the pipe main body 2 via the strainer 3 is in contact with the magnesium pipe 6 disposed inside the pipe main body 2 while having a lower end. To the outlet side. Although the ground water 4 contains iron ions, magnesium, which is the main component of the magnesium pipe 6, has a higher ionization tendency than iron and is likely to become ions in an aqueous solution. For this reason, when the groundwater 4 collected through the strainer 3 comes into contact with the magnesium pipe 6, the magnesium component is easily dissolved in the groundwater 4. As the magnesium component is dissolved (ionized), electrons are released into the groundwater 4.

On the other hand, iron bacteria (iron bacteria) living in groundwater oxidize divalent iron ions, which are also dissolved in groundwater, to trivalent iron ions, and use the oxidation energy generated at that time. It is known to survive and proliferate. The trivalent iron ions become reddish brown iron hydroxide (Fe (OH) ₃ ) and settle together with the organic matter produced by the iron bacteria and settle inside the water collecting pipe, causing slime that causes the water collecting pipe to become clogged. Form. At this time, in the groundwater, the electrons released along with the ionization of the magnesium component described above react with the divalent iron ions to prevent oxidation to the trivalent iron ions. That is, magnesium acts as an iron reducing agent.

  That is, in the water collecting pipe 1, magnesium, which is the main component of the magnesium pipe 6 disposed inside the pipe main body 2, dissolves in the ground water and emits electrons into the ground water. Since the oxidation of divalent iron ions contained in the groundwater is suppressed, the production of trivalent iron ions that are the causative substance of slime is suppressed. Further, by suppressing the oxidation of divalent iron ions, the oxidation energy generated during the oxidation is reduced, and the growth of iron bacteria that survive using this energy is also suppressed. Thereby, the adhesion of slime to the inside of the tube body 2 is prevented.

  In addition, by connecting the elbow pipe E to the outlet of the pipe body 2 as shown in the figure, the magnesium pipe 6 is impregnated in the ground water in the portion where the ground water near the outlet is stored, and the ground water comes into contact with the magnesium pipe 6. Sufficient time can be secured. For this reason, dissolution of the magnesium component into the ground water and emission of electrons into the ground water can be continued for a long time, and the slime adhesion preventing effect is improved. Moreover, since the range in which groundwater contacts with outside air is limited only to the vicinity of the opening of the elbow pipe E, the oxidation of divalent iron ions contained in the groundwater itself is suppressed, and the slime adhesion preventing effect is further enhanced. be able to.

  Next, the slime adhesion prevention method to the water collecting pipe which concerns on one embodiment of this invention is demonstrated. Here, a case where the slime adhesion preventing method is applied to an existing water collection pipe installed in a groundwater drainage facility such as horizontal boring will be described as an example.

(Magnesium tube insertion process)
First, a metal member mainly composed of magnesium is inserted and disposed from the outlet side into the pipe body of an existing water collection pipe installed in the groundwater drainage facility. The metal member is arranged along the bottom of the pipe body so that the metal member can be surely brought into contact with the groundwater flowing from the upper end when arranged inside the pipe body of the water collecting pipe. As the metal member, the above-described AZ31 magnesium alloy tube can be used.

  Then, utilizing the fact that the ionization tendency of magnesium is higher than that of iron, the magnesium component is dissolved in the groundwater and electrons are emitted into the groundwater. The emitted electrons react with divalent iron ions dissolved in the groundwater, and the divalent iron ions are oxidized to suppress the action of trying to become trivalent iron ions. This reduces the oxidation energy generated in groundwater, suppresses the growth of iron bacteria, suppresses the formation of trivalent iron ions that cause slime, and prevents the slime from adhering to the tube body. To do.

  In order to continuously dissolve the magnesium component in the groundwater, connect the elbow pipe as described above to the outlet of the pipe body to temporarily store the groundwater and impregnate the storage section with the magnesium pipe. . Thereby, sufficient time for groundwater to contact the magnesium pipe 6 can be secured, and dissolution of the magnesium component into the groundwater and emission of electrons into the groundwater can be sustained for a long time. Further, the range in which the groundwater comes into contact with the outside air is limited only to the vicinity of the opening of the elbow pipe, and the oxidation of divalent iron ions contained in the groundwater itself is suppressed. Therefore, the slime adhesion preventing effect can be further enhanced.

(Spreading process of iron elution inhibitor)
Moreover, as an additional factor for promoting the slime adhesion preventing effect, in addition to the insertion process of the magnesium tube, a metal material mainly composed of typical elements belonging to Group 2 of the periodic table (for example, magnesium metal material or calcium-containing material) It is also effective to embed or disperse the material in the topsoil of the natural ground where the water collection pipe is embedded as an iron elution control material.

  In other words, these substances, which are more easily ionized than iron, react and neutralize the causative substances sulfate, nitrate, and chloride contained in acid rain. It has the effect of mitigating and suppressing the inflow of iron ions into the water collection pipe. In addition, since calcium-containing materials are easily soluble in water, a high immediate effect can be expected in the effect of preventing the elution of iron by acid rain. On the other hand, since the dissolution speed of the magnesium metal material is relatively gentle, the elution effect of iron can be maintained for a long time. Thus, if the inflow of iron ions into the water collection pipe is suppressed, the concentration of iron ions in the groundwater can be suppressed, and the effect of preventing the adhesion of slime into the water collection pipe can be further improved. .

  In addition, the present inventors implemented the above-mentioned slime adhesion prevention method in the actual landslide site, and performed the confirmation test about the effect. Hereinafter, the test results will be described. The confirmation test was conducted by horizontal boring in Niigata Prefecture, a groundwater drainage facility for landslides in the mudstone area.

  FIG. 2 shows the state of slime adhesion to the horizontal boring before the test. This horizontal boring is a facility where a large amount of iron bacteria slime adheres to the water collection pipe in less than one year after the establishment of the facility, and it can be seen that a large amount of slime adheres to the water collection pipe. The total length of each drainage pipe installed in this horizontal boring is about 60m from the lower end outlet to the upper end, but before the start of the test, the section about 20m deep from the outlet of the water collection pipe, the drainage pipe protection wall, etc. Was cleaned with a brush or the like.

  The confirmation test was conducted with three water collecting pipes located on the right side in FIG. In one of them, five AZ31 magnesium alloy tubes (3% aluminum, 1% zinc, 96% magnesium) having a length of 1.9 m were connected as an example, and a magnesium tube having a total length of about 10 m was inserted. did. Also, in another one, five aluminum alloy pipes whose surface was polished with sandpaper were connected, and an aluminum pipe having a total length of about 11 m was inserted (Comparative Example 1). Nothing was inserted into one of these (Comparative Example 2), and the state of slime adhesion was compared for about one month from the start of the test. In addition, the elbow pipe was connected to the discharge port of each water collection pipe, and the adhesion state of the slime in the vicinity of each hole was comparatively observed.

  Table 1 shows the pH and total iron (T-Fe) of drainage from the water collection pipe one day after the start of the test. The pH is 6.62 to 6.94 and is neutral. Total iron (T-Fe) is 22.1 to 29.7 mg / l, and the water quality is very easy for slime to adhere to the water collecting pipe. The amount of slime attached to the water collection pipe increases when total iron (T-Fe) is 1 mg / l or more.

  FIG. 3 shows the appearance of the slime adhesion state to the elbow tube hole mouth about one month after the start of the test. In FIG. 3, (a) is a magnesium tube inserted (Example), (b) is an aluminum tube inserted (Comparative Example 1), and (c) is nothing (Comparative Example 2). ). In addition, in the water collection pipe inserted with the magnesium pipe and the water collection pipe inserted with the aluminum pipe, the magnesium pipe and the aluminum pipe cannot be arranged in the section from the discharge port of the water collection pipe to the hole of the elbow pipe, respectively. Since each slime started to adhere, a magnesium tube cut short was also inserted into this section.

  FIG. 4 shows the internal situation of each elbow tube hole. As shown in FIG. 4 (a), the slime adhesion was hardly observed in the case where the magnesium tube was inserted, but as shown in FIGS. 4 (b) and (c), the aluminum tube was inserted. Slime adherence was observed in the case where nothing was inserted.

  FIG. 5 shows a change state of the magnesium pipe and the aluminum pipe inserted into the water collecting pipe. About the magnesium pipe, the part which was in contact with groundwater and the stored waste_water | drain became black-green over the full length of about 10 m, and adhesion of slime was hardly recognized. On the other hand, about the aluminum pipe, the section about 6m from the hole mouth became reddish brown, and the section about 6-10m from the hole mouth was hardly reddish brown. The section which became reddish brown is the section where slime produced by iron bacteria adheres to the aluminum tube.

  FIG. 6 shows the state of drainage stored in the water collection pipe. (A) is the state of the waste_water | drain stored in the water collection pipe which inserted the magnesium pipe | tube. The color of the wastewater was black, and no colloidal organic matter produced by iron bacteria was observed in the wastewater. (B) is the state of the waste_water | drain stored in the water collection pipe which inserted the aluminum pipe. The color of the wastewater was reddish brown, and floating of colloidal organic matter produced by iron bacteria was observed in the wastewater.

  Divalent iron ions are easily oxidized in the presence of oxygen and change to reddish brown iron hydroxide, but the hue changes from light green to grayish green to black brown to reddish brown as oxidation progresses. It is known to do. In other words, the magnesium pipe turned black-green in this test and the wastewater stored in the water collection pipe was black, so the magnesium alloy inhibited the oxidation of iron ions, and the oxidation of iron ions did not progress. It was shown that

  Table 2 shows the change in the amount of drainage from the elbow hole in the month when the test was conducted.

  From this result, in the water collecting pipe with the magnesium pipe inserted, there was no significant change in the amount of drainage at the start and end of the experiment, and the difference between the minimum amount of drainage and the maximum amount of drainage was relatively small. Although the flow rate decreased somewhat during the drought season in the summer, the flow rate remained almost constant throughout the period.

  In the water collection pipe (Comparative Example 1) into which the aluminum pipe was inserted, the amount of drainage decreased greatly at the end of the experiment. Fluctuations were so great that there was almost no flow rate and measurement was impossible. This is presumably because the clogging of the pipe had progressed due to the slime generated in the water collection pipe. In addition, there was a scene where the groundwater staying inside the pipe was discharged out of the pipe together with the slime during the rain. Moreover, although the drainage amount at the end of the experiment was also reduced in the water collecting pipe (Comparative Example 2) into which nothing was inserted, this was also the same as in Comparative Example 1, and the clogging of the pipe due to the generation of slime inside the pipe This is thought to be because of progress.

  In addition, the effect was not recognized in the water collection pipe which inserted the aluminum pipe because aluminum was easy to form an oxide film, and the film was comparatively strong, and became a factor which inhibited ionization of aluminum. it is conceivable that. In other words, in the ionization sequence expressed by the magnitude of the ionization tendency, magnesium and aluminum are adjacent to each other, but there is a considerable difference in solubility (ionization). It is done.

  As described above, according to the water collecting pipe for groundwater drainage facility according to the present invention, and the slime adhesion preventing method in the water collecting pipe for groundwater drainage facility, the magnesium component is dissolved in the groundwater to generate electrons. Can be prevented very easily and rationally. For this reason, the regular maintenance like the conventional one becomes unnecessary, and the maintenance management cost in the groundwater drainage facility can be reduced.

  In the above-described embodiment, the example in which the above-described AZ31 is used as the magnesium pipe has been described. However, the magnesium pipe is not limited to this, and if an alloy containing as much magnesium component as possible is used, The effect of the invention can be continued for a longer period.

  In the above embodiment, an example in which three magnesium pipes 6 are disposed has been described. However, the number of the magnesium pipes is not limited to this, and a single long magnesium pipe is used instead of a plurality of magnesium pipes. It may be used. Further, the magnesium tube 6 is not tubular but can be rod-shaped. In this case, a sufficient gap is secured between the inner peripheral surface of the tube body 2 and the outer peripheral surface of the magnesium rod. It is also possible to put short pieces such as magnesium pipes and magnesium rods that have become waste materials into a net-like container or a container with a hole, and insert these containers into the pipe body 2 to contact with groundwater. These forms can be inserted into the pipe body 2 and are not particularly particular in shape as long as they do not hinder the outflow of groundwater.

1 Drainage pipe 2 Pipe body 3 Strainer 4 Groundwater 5 Drainage 6 Magnesium pipe A Ground mountain B Earth wall E Elbow pipe

Claims (7)

It is a water collection pipe for groundwater drainage facilities that is buried on the slope of a natural mountain,
A strainer that collects groundwater of the natural ground is drilled in the outer peripheral wall, and has a pipe main body provided with a discharge port for draining groundwater collected through the strainer at the downstream end,
Inside the tube body, a metal member mainly composed of magnesium that generates electrons that dissolve in contact with groundwater collected via the strainer and suppresses oxidation of iron ions contained in the groundwater. A drainage pipe for groundwater drainage facilities, characterized in that a groundwater flow path is secured.   The water collecting pipe for groundwater drainage facilities according to claim 1, wherein the metal member containing magnesium as a main component is formed of a magnesium pipe having a smaller diameter and rounder than the pipe body.   An elbow pipe for temporarily storing the groundwater collected through the strainer near the outlet of the pipe body and draining the stored groundwater from a position above the outlet is provided at the outlet of the pipe body. The water collection pipe | tube for groundwater drainage facilities of Claim 1 or 2 connected. A method for preventing the adhesion of slime that induces blockage of a water collecting pipe for groundwater drainage facilities that is buried in a slope of a natural mountain,
A strainer that collects groundwater of the natural ground is drilled in the outer peripheral wall, and magnesium is placed inside the pipe body provided with an outlet for draining the groundwater collected through the strainer at the downstream end. A metal member as a main component is inserted and arranged, brought into contact with the groundwater collected in the pipe body through the strainer, and the electrons generated when the magnesium component contained in the metal member is dissolved in the groundwater, A method for preventing slime from adhering to a drainage pipe for a groundwater drainage facility, which prevents slime from adhering to the inside of a pipe body by acting on iron ions contained therein to suppress oxidation of the iron ions.   The slime adhesion preventing method according to claim 4, wherein the magnesium-based metal member is a magnesium tube having a smaller diameter and rounder than the tube body.   An elbow pipe for temporarily storing the groundwater collected through the strainer near the outlet of the pipe body and draining the stored groundwater from a position above the outlet is provided as an outlet of the pipe body. The slime adhesion preventing method according to claim 4 or 5, wherein the slime adhesion method is connected.   The iron component elution suppression material which suppresses that the iron component contained in the said natural ground elutes and flows in into the pipe main body of a water collection pipe is embed | buried or sprayed on the surface of the said natural ground. The slime adhesion prevention method of description.