JP6022978B2 - Method and apparatus for preventing scattering of pollutants such as demolition dust - Google Patents

Description

  The present invention relates to a method and an apparatus for preventing the scattering of pollutants such as demolition dust such as dust and pollutants generated in the construction demolition work in the construction field.

  When dismantling the existing construction, the roof is normally dismantled, but dust and contaminants are generated as shown in FIG.

Conventionally, the following techniques have been applied as means for suppressing dust and the like generated during the dismantling of the existing construction.
(1) Normal sprinkling with water spray guns A general dust generation suppression method suppresses dust scattering by moistening topsoil and dismantling members.
The following patent document is one of them, and as shown in FIG. 13, a water supply passage hole is formed in the swivel joint 2 disposed in the center of the slewing bearing of the crusher 1, and the water supply passage is made. A water spray nozzle 3 is arranged at the downstream end of the hole, and water from the water supply source is sprayed from the inside of the crusher 1 toward the periphery of the rocker beam for the crusher 1 through the water supply passage hole and the water spray nozzle 3. Moreover, the operation part of the stop valve 4 which operates the start and stop of watering was arrange | positioned inside the cab 5 of a construction machine.
Japanese Utility Model Publication No. 5-58758

  According to this patent document 1, the water discharged from the watering nozzle 3 can automatically follow the location where the crusher 1 performs crushing to perform reliable watering. Moreover, since the operation part of the stop valve 4 which operates the start and stop of watering is arrange | positioned in the driver's cab interior, it is very convenient because a driver | operator can be in the cab and can operate as needed. Therefore, it is possible to exert a sufficient effect for labor saving and dust generation prevention during crushing work.

(2) Mist watering By spraying water in a mist, the contact area with the dust is increased and the washing-off effect is improved.

(3) Dust-proof net The air speed by the net reduces the wind speed and reduces the amount of accumulated dust. The following patent document discloses a plurality of nets that are supported by a structural part of a building and are arranged so as to protrude above the upper end of the building along the side of the building as a scattering prevention device using such a dustproof net. A holding part and a protective net that is held by the plurality of net holding parts at a position above the upper end of the building and covers the upper surface of the building, and the plurality of net holding parts are independent of each other. It is characterized by being vertically movable with respect to the building.
JP 2011-17230 A

  According to Patent Document 2, scattered objects from the upper surface side can be prevented by the protective net during the construction of the building, and the net holding portion can be moved in the vertical direction. The height to the net can be adjusted, and the height of the construction work space on the upper surface of the building can be adjusted appropriately. In addition, the height of the protective net in each area can be adjusted frequently according to the progress of construction in each area.

(4) Dispersion of dust coagulant Coagulates the surface of accumulated dust and earth and sand, and suppresses the rising of wind.
(5) Addition of dust scattering inhibitor to water spray By adding a surfactant or the like to the water spray, the compatibility between water and dust is improved and the washing-off performance is improved.
(6) Sealing of the dismantling work space Sealing the work space with temporary panels, etc. minimizes dust scattering outside the site.
(7) Dust collector By installing a dust collector or air intake duct near the dust generation point, collect the dust before it is scattered.

  The mechanism of generating dust and pollutants shown in FIG. 12 will be described in more detail. As shown in FIG. 14, the normal diffusive property is a peeling shear layer (= with a backflow) due to peeling occurring at the windward corner. Since a strong turbulent mixing layer is formed on the top of the building, dust and pollutants generated during demolition work and the like diffuse in a vertical direction. For this reason, it is difficult to collect dust and pollutants, and if those substances are scattered in the air, they will flow out of the premises.

The conventional means (1) to (7) have the following problems.
(1) In normal sprinkling with water spray guns, it is possible to suppress the scattering of accumulated dust by moistening the topsoil and dismantling members, but when disassembling concrete and other members, the dust does not soak into the interior. Occurrence is inevitable, and there is a possibility that it will not reach the member during strong winds. The washing-off effect can hardly be expected because the contact surface with the dust is limited.
(2) Although mist-like water spray can improve the washing-off effect, it is more susceptible to wind than water spray guns, and the operator must always discharge water to the dismantling site as with water spray guns.
(3) Dust-proof nets can reduce the amount of accumulated dust, but there is little effect of retaining dust once generated in the premises. For dust that has been scattered in the air due to destruction work, etc. The effect is low.
(4) Although the dust coagulant spray prevents the dust from being scattered, it cannot suppress the generation of dust in the destruction work of concrete or the like.
(5) The addition of the dust scattering inhibitor to the water spray can improve the washing-off performance, but increases the cost of capital investment. Moreover, the effect becomes low at the time of a strong wind like other watering.
(6) Sealing of the dismantling work space can minimize dust scattering to the outside of the premises, but it increases the cost, restricts the size of heavy equipment to be used, and deteriorates the work environment due to sealing.
(7) In the case of dust collectors and intake ducts, unlike air supply, air is sucked from the entire intake surface, so there is no point in installing an intake port very close to the dust generation source, and there is a tendency for the equipment to become large. There are significant restrictions on the handling of equipment at the site of dismantling.

  The purpose of the present invention is to eliminate the inconvenience of the conventional example, and suppress the formation of a peeling shear layer at the top of the building, so that dust and pollutants generated by dismantling and other cases are spread over a wide range in the vertical direction at the top of the building. It is an object of the present invention to provide a method and an apparatus for preventing the scattering of pollutants such as dismantled dust, which can flow downstream without being diffused, thereby facilitating the collection of dust and pollutants.

  In order to achieve the above object, as a method for suppressing the scattering of pollutants such as demolition dust, the present invention according to claim 1 is characterized in that a vane for receiving wind is installed at a corner of the building top located upstream of the inflow air. And by attracting the wind to the center of the building top, the thickness of the peeling shear layer formed due to the corner of the building top is reduced, and the mixed layer formed on the entire building top is suppressed. It is a summary.

  As a device for suppressing the scattering of pollutants such as demolition dust, the present invention according to claim 3 is provided with a vane that attracts wind to the center of the building top at the corner of the building top located upstream of the inflowing wind. Is a summary.

  According to the first and third aspects of the present invention, it is possible to suppress the formation of the peeling shear layer at the top of the building, thereby allowing the wind to be attracted to the center of the building top. Is.

  Specifically, a vane that receives wind that rises by colliding with the side of the building on the upstream side is installed at the corner of the building top located on the upstream side of the inflow wind, and by attracting it to the center of the building, The thickness of the peeling shear layer formed due to the corner portion is reduced, and the mixed layer formed on the entire building top is suppressed. Thereby, the turbulent flow diffusion in the vertical direction is suppressed, and the wind flowing into the building top portion flows from the upstream side to the downstream side without being disturbed.

  In this flow field, pollutants such as dust generated at the top of the building are not easily diffused turbulently in the vertical direction (i.e., soaring is difficult to occur), so the outflow route of pollutants may be limited to the leeward side. It becomes possible.

  The gist of the present invention described in claim 2 and claim 4 is that the trapping means is provided on the leeward side in the flow field formed by the vanes.

  According to the present invention of claim 2 and claim 4, in the flow field formed by the vane, it is possible to suppress pollutants scattered outside the site by providing a filter or duct on the leeward side. Become.

  As described above, the method and apparatus for preventing the scattering of pollutants such as demolition dust of the present invention suppresses the formation of a peeling shear layer at the top of the building, so that dust generated by dismantling and other cases at the top of the building The pollutant can flow downstream without diffusing in a wide range in the vertical direction, thereby facilitating the recovery of dust and pollutant scattering materials.

  In this way, dismantling dust and pollutant scattering can be suppressed without impairing dismantling workability, and air can be removed without dust washing and dust collection by attaching a dust scattering inhibitor to the water spray. It becomes possible to collect the dust floating inside.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a longitudinal side view showing one embodiment of a method and apparatus for preventing the scattering of pollutants such as demolition dust according to the present invention, FIG. 2 is a plan view of the same, and 6 in FIG.

  In the present invention, a vane (wind receiver, deflecting device) 8 for receiving wind is installed at a corner portion 7 at the top of the dismantling target building 6 located on the upstream side of the inflow air.

  The vane 8 is provided as an “overhang” of about 3 to 4 m on the windward side of the dismantling target building 6, and a gap 9 of about 3 m is provided between the “overhanging” and the dismantling target building 6, It is a path through which the combined upflow flows.

  As shown in FIG. 2, the width of the vane 8 is substantially the same as the width α of the dismantling target building 6.

  The vane 8 is a horizontal body, and the vane member itself does not require any special ingenuity, and there is no problem if it is a material that can receive wind such as a sheet or temporary roofing material such as corrugated board or plywood. . It is assumed that the end 8a does not come out to the dismantling target building 6 side. (This is to prevent the wind from swirling.)

  The vane 8 attracts wind to the center of the top of the building 6 to be demolished, thereby reducing the thickness of the peeling shear layer formed due to the corner 7 at the top of the building 6 to be demolished. The mixed layer formed on the entire top of the building 6 is suppressed.

  Thereby, as shown in FIG. 3, the airflow that collides with the side surface of the dismantling target building 6 merges with the wind in the mainstream direction to suppress separation, and the vertical mixing is weakened. The pollutant will flow downstream without greatly rising.

  FIG. 8 shows the results of examining the effect of the peeling shear layer suppression vane by CFD (computational fluid dynamics) analysis. It can be seen that the peeling shear layer is suppressed by the introduction of the vane 8.

  As another embodiment, the shape of the vane 8 may not be the “single point protruding” type shown in FIG. 1 but may be a square shape that forms a contracted flow as shown in FIG. 4.

  In the present embodiment, the end of the vane 8 does not necessarily have to be installed with the overhanging portion β. However, by providing the overhanging portion β, the influence due to the separation is reduced, more contraction is formed, the wind becomes stronger, and the speed is increased. The mixed layer can be suppressed by eliminating the difference.

  5 and 6 show a modification of the installation of such a C-shaped vane 8. FIG. 5 shows a case where the C-shaped vane 8 is provided on the dismantling target building 6 side. 6 is a case where it is provided so as to cover the dismantling target building 6 side. In the case of FIG. 6, the vane 8 is installed with the overhanging part β as in FIG. 4.

  Comparing the examples of FIGS. 4, 5, and 6, FIG. 5 is the least effective. The reason for this is that when the overhang is retracted to the building side in this way, an upward flow is generated due to separation at the corner of the building and it is difficult to flow into the “C” vane. (In addition, since the horizontal flow is not lost at all, a contracted flow effect can be expected.)

  In the case of FIG. 4, the installation of the C-shaped vane 8 is just before the separation at the corner, and the upward flow does not occur and the horizontal flow is maintained and flows into the “C” vane. Increases effectiveness.

  As a further embodiment, the trapping means 10 is provided on the leeward side in the flow field formed by the vanes 8 as shown in FIGS. FIG. 7 shows a case where a filter 11 is installed as the capturing means 10.

  FIG. 8 shows a case where a duct 12 is formed as the capturing means 10 and a dust collector 13 or the like is installed therein.

  FIG. 9 shows the case where the surroundings of the demolition target building 6 are surrounded by the temporary enclosure 14 as the capturing means 10, and a void (gap) 16 of about 2 to 3 m is provided between the temporary enclosure 14 and the demolition target building 6. Provided. No special device is required for the member forming the temporary enclosure 14, and there is no problem with a panel or a sheet as long as the void 16 can be set.

  Further, the height of the temporary enclosure 14 exceeds the dismantling target building 6 to some extent, for example, about 3 meters from the building height, a laterally extending ridge portion 15 having an upper end of about 1 m is formed, and the overhang is formed. A “wind receiving” space of about 2 to 3 m is provided between the part 15 and the roof height of the dismantling target building 6.

  In this manner, the void (gap) 16 between the dismantling target building 6 and the temporary enclosure 14 is in a state in which ventilation is possible, and dust and the like generated by the dismantling of the building are drawn into the void 16 and captured. .

  As shown in FIG. 10, it can be confirmed that the formation of peeling shear is suppressed by the vanes. In addition, although the figure at the time of introduction of this patent technology shown in FIG. 10 shows a flow field provided with a supplementary duct on the downstream side, it hardly contributes to suppression of the peeling shear layer, and contributes exclusively by vanes. The Lord. In addition, as shown in FIG. 11, it was confirmed that the pollutant flows downstream without diffusing in the vertical direction, and that the pollutant can be efficiently recovered by providing a capturing means 10 such as a duct downstream.

BRIEF DESCRIPTION OF THE DRAWINGS It is a vertical side view which shows 1st Embodiment of the scattering suppression method and apparatus of contaminants, such as dismantling dust of this invention. It is a top view which shows 1st Embodiment of the scattering suppression method and apparatus of contaminants, such as dismantling dust of this invention. It is explanatory drawing of the scattering suppression method and apparatus of contaminants, such as dismantling dust of this invention. It is a vertical side view which shows 2nd Embodiment of the scattering suppression method and apparatus of contaminants, such as dismantling dust of this invention. It is a partial vertical side view which shows the modification of 2nd Embodiment of the scattering suppression method and apparatus of contaminants, such as dismantling dust of this invention. It is a partial vertical side view which shows the other modification of 2nd Embodiment of the scattering suppression method and apparatus of contaminants, such as dismantling dust of this invention. It is a vertical side view which shows 3rd Embodiment of the scattering suppression method and apparatus of contaminants, such as dismantling dust of this invention. It is a vertical side view which shows 4th Embodiment of the scattering suppression method and apparatus of contaminants, such as dismantling dust of this invention. It is a vertical side view which shows 5th Embodiment of the scattering suppression method and apparatus of contaminants, such as dismantling dust of this invention. It is explanatory drawing which shows the effect examination result of the scattering suppression method and apparatus of contaminants, such as dismantling dust of this invention. It is explanatory drawing which shows the examination result of the effect of 5th Embodiment of the scattering suppression method and apparatus of contaminants, such as dismantling dust of this invention. It is explanatory drawing of demolition dust generation | occurrence | production. It is explanatory drawing which shows one of the prior art examples. It is explanatory drawing which shows a normal diffusion property.

DESCRIPTION OF SYMBOLS 1 ... Crusher 2 ... Swivel joint 3 ... Sprinkling nozzle 4 ... Stop valve 5 ... Operation room 6 ... Demolition object building 7 ... Corner part 8 ... Vane 8a ... End part 9 ... Air gap 10 ... Capture means 11 ... Filter 12 ... Duct 13 ... Dust collector 14 ... Temporary enclosure 15 ... Overhang 16 ... Void (gap)

Claims (4)

  Peeling shear formed due to the corner of the top of the building by installing a vane that receives the wind at the corner of the top of the building located on the upstream side of the incoming air and attracting the wind to the center of the top of the building A method for suppressing scattering of pollutants such as demolition dust, wherein the thickness of the layer is reduced and the mixed layer formed on the entire top of the building is suppressed.   The method for suppressing scattering of contaminants such as demolition dust according to claim 1, wherein a trapping means is provided on the leeward side in the flow field formed by the vanes.   A device for suppressing the scattering of pollutants such as demolition dust, characterized in that a vane for attracting wind to the center of the building top is installed at the corner of the building top located on the upstream side of the incoming wind.   The apparatus for suppressing the scattering of pollutants such as demolition dust according to claim 3, wherein a trapping means is provided on the leeward side in the flow field formed by the vanes.