Block for constructing retaining wall, prefabricated reinforced retaining wall constructed using the block and construction method of the prefabricated reinforced retaining wall
Provided are blocks for constructing a retaining wall, a prefabricated reinforced earth retaining wall constructed using the blocks, a method for constructing the prefabricated reinforced earth retaining wall. The block for constructing a retaining wall comprises a front surface 10 forming a surface of the retaining wall, and a rear surface 20; left and rights sides 30 and 30′ having corresponding intermeshing portions 32 and 32′ formed thereon; a top surface 40 having reinforcement member insertion grooves 44 formed in a front-to-rear direction, and fixture grooves 46 formed on either side of the front of the reinforcement member insertion grooves 44 for fixing the reinforcement member or anchor; and a bottom surface 50 corresponding to the top surface 40, wherein a connecting pin insertion hole h1 for pinning upper and lower blocks with a connecting pin and a lifting pin insertion hole h2 for simultaneously lifting the upper and blocks, penetrate through the top and bottom surfaces 40 and 50.
The present invention relates to blocks for constructing a retaining wall, a prefabricated reinforced earth retaining wall constructed using the blocks, a method for constructing the prefabricated reinforced earth retaining wall, and a method for repairing the retaining wall. The present invention is devised to reduce transportation and material costs by making a front wall face of the retaining wall light in weight while offering excellent workability with use of equipment to minimize on-site labor during construction. Other advantages of the invention include high durability in enduring displacement of an earthen structure, which may occur after construction, and easier repair works in an event of partial damages occurring to the retaining wall.
BACKGROUND ARTA prefabricated reinforced earth retaining wall, which is a field related to the present invention, has the following advantages over conventional concrete retaining walls: efficient use of limited land is allowed because the retaining wall can be constructed vertically. Use of factory-manufactured products ensures reliability in quality. The reinforced earth retaining wall also eliminates the need for special equipment and is easily constructed, which allows a shorter construction period. Also, strict quality control of earthen structures is possible. Furthermore, since the reinforced earth retaining wall has a flexible structure, it is possible to flexibly cope with differential subsidence of foundation ground or seismic load. In addition, since the front wall face is lightweight compared to the conventional concrete retaining wall, foundation treatment is simplified, ensuring an economic efficiency.
In 1980, Korea's first reinforced earth retaining wall was tentatively constructed along national highway by Architecture Laboratory of the Ministry of Construction using a galvanized steel plate as a reinforcement member. Although since then several test construction works using the same reinforcement member and on-site investigation were carried out by government-funded institutions including Architecture Laboratory, Korea Highway Corporation, and Korea Land Corporation, some problems were found in galvanizing technology, selection of backfill soil (reinforced earth), and construction management during the investigation on reinforced earth retaining wall using a galvanized steel sheet as reinforcement member. For these reasons, reinforced earth retained walls using the galvanized steel plate as reinforcement member failed to gain popularity domestically. By solving problems associated with galvanized steel plates with introduction of band-shaped geotextile reinforcement members in 1986, the band-shaped geotextile has emerged as a new reinforcement member. While a prefabricated block-type reinforced earth retaining wall using high strength geogrids as a reinforcement member was introduced in 1994, a panel-type reinforced earth retaining wall using a band-shaped geotextile reinforcement member and a prefabricated block-type retaining wall using geogrids now have a wide range for use.
Meanwhile, the conventional prefabricated panel-type reinforced earth retaining wall had the following disadvantages. Above all, the monotonous shape and appearance of the conventional panel-type reinforced earth retaining wall are unappealing. From an environmental-friendly viewpoint, the conventional retaining wall that is not in harmony with its surroundings, since growth of vegetation is not possible, looks very bleak. Furthermore, even where a minor damage occurs to a lower panel of the retaining wall, conventionally, an extensive disassembling work should have been done on an overlying panel as well as adjacent panels to replace the damaged panel with a new one. Thus, repairing the conventional retaining wall is expensive, labor-intensive and even more difficult than newly constructing a retaining wall, and requires a considerable amount of equipment.
The conventional prefabricated block-type reinforced earth retaining wall has problems that since blocks are alternately staggered, an underlying block of an overlapping portion tends to be sheared easily if a load from an upper portion of the retaining wall acts as a shearing force after construction is completed. The repairing works have difficulties comparable to those encountered with the panel-type reinforced earth retaining wall. Since the blocks for the conventional reinforced earth retaining wall have a front-to-rear length that is much greater than the left-to-right width in order to prevent overturning and localized overlooking portioning, individual blocks have a heavy load, consuming much constructional material accordingly. This heavy load also makes construction of the retaining wall difficult, thus causing inconvenience in work. Furthermore, because of difficulties in mobilizing equipment for construction, a construction period may be prolonged.
DISCLOSURE OF THE INVENTIONThe present invention is devised to reduce material and construction cost by offering lightweight retaining wall blocks.
The present invention provides a prefabricated block-type reinforced earth retaining wall which can form a structurally strengthened wall and is easily repaired in an event where the reinforced earth retaining wall is partially damaged.
The present invention also provides blocks for constructing a prefabricated reinforced earth retaining wall capable of offering excellent efficiency for growth of vegetation.
Further, the present invention provides blocks for constructing a retaining wall, which can offer high durability in enduring displacement of a reinforced earth, which may occur after construction is completed, and can be easily repaired in an event where the reinforced earth retaining wall is partially damaged.
The present invention also provides a method for constructing a prefabricated reinforced-earth retaining wall using the blocks, which can construct a strengthened retaining wall structure, and a method for repairing a damaged portion in an event where the reinforced earth retaining wall is partially damaged.
According to an aspect of the present invention, there is provided a block for constructing a retaining wall comprising: a front surface forming a surface of the retaining wall, and a rear surface contacting a reinforced earth structure; left and right sides having corresponding intermeshing portions formed thereon for intermeshed connection between adjacent blocks, respectively; a top surface having reinforcement member insertion grooves formed in a front-to-rear direction, into which a reinforcement member or an anchor for connecting the reinforcement member is fitted and fixture grooves formed on either side of the front of the reinforcement member insertion grooves for fixing the reinforcement member or anchor; and a bottom surface corresponding to the top surface, wherein a connecting pin insertion hole for pinning upper and lower blocks with a connecting pin and a lifting pin insertion hole for simultaneously lifting the upper and blocks, penetrate through the top and bottom surfaces.
According to another aspect of the present invention, there is provided a method for constructing a retaining wall using the block, the method comprising: digging trenches for footing and then casting footing concrete in order to construct the footing; placing blocks on the cast footing in a horizontal direction so that they are adjacent to one another and stacking and aligning another block on each block placed horizontally using a vertical connecting pin P′ in order to install the blocks; and arranging reinforcement members on a reinforced earth structure and filling and compacting the reinforced earth placed in the rear of the installed block with soil, such that a leading edge of each reinforcement member is inserted into a reinforcement member insertion groove to thereby connect the reinforcement member to the block, the reinforcement members are arranged on the reinforced earth, and then, the reinforcement members arranged on the reinforced earth are backfilled and compacted with soil.
According to still another aspect of the present invention, there is provided a method for repairing a reinforced earth retaining wall constructed by the constructing method, the method comprising: lifting up blocks positioned above the damaged portion of a block, the blocks belonging to a row containing the damaged block, to disassemble the overlying block after lifting a reinforcement member fitted into a reinforcement member insertion groove and separating the same from the block; removing the damaged block after disassembling the overlying block; placing a new block at the location of the previously damaged block, inserting a vertical connecting pin, and fitting a leading edge of the reinforcement member buried inside a reinforced earth into a reinforcement member insertion groove of the new block in order to connect the reinforcement member to the block; and reversing the order of the above disassembling step to reconstruct the disassembled block.
Also, the present invention provides a panel for a prefabricated block-type reinforced earth retaining wall comprising: a plurality of unit blocks each unit including a front surface forming an outer surface of a retaining wall, a rear surface contacting a reinforced earth structure, a bottom surface and a top surface having a plurality of channels and throughholes vertically formed at a predetermined position of each channel, and left and right sides having an insertion portion and a locking groove, creating a portion into which an insertion portion for preventing the unit blocks of an adjacent panel from alienating from or getting close to each other by interlocking unit blocks of the adjacent panel, is inserted; connecting elements inserted into the throughholes in a state in which the plurality of unit blocks are vertically stacked; and connecting means engaged with one end of the connecting element and connecting the stacked plurality of unit blocks with one another.
The prefabricated block-type reinforced earth retaining wall can be manufactured by vertically stacking two, three, or four blocks having a uniform shape at factories or on construction sites, assembling the stacked blocks with connecting element and assembling means, and piling up the assembled panels on the foundation of the retaining wall using equipment. Since adjacent panels are connected and fixed by inserting the fixture element into the insertion portion and locking groove formed on either side of each unit block of the panel and engaged to the rear of the panel by inserting a clamp for temporary fixing, it is possible to prevent separation or adhesion due to interlocking between adjacent panels. Another advantage is to improve resistance against vibration or other external forces since each panel is spaced apart from adjacent panels by a predetermined distance by the insertion portion.
BRIEF DESCRIPTION OF THE DRAWINGS
Since the block B of the present invention has a front-to-rear length that is much less than a left-to-right width, as evident from the illustrative first embodiment of the present invention, it is possible to reduce the number of blocks needed to construct a retaining wall by more than half compared to a conventional block where the former is much greater than the latter while providing a lightweight structure. According to the invention, since upper and lower blocks are joined together firmly as described later, this strong adhesion between upper and lower blocks can prevent the wall from localized sliding (bulging) or overturning.
Reference character H denotes a hollow that penetrates the top and bottom surfaces 40 and 50 to reduce an earth pressure exerted on the block while offering a lightweight block. An upper portion of the rear surface 20 that is in contact with a reinforced earth is cut by formation of the reinforcement member insertion grooves 44. The cuffing surface is inclined rearward and downward.
In addition, while the connecting pin insertion pins h1 are formed on either side of the top and bottom surfaces 40 and 50, lifting pin insertion holes h2 are formed at the center thereof in consideration of the center of gravity during lifting. An extension groove h2′ having a larger diameter is formed around the lifting pin insertion hole h2 on the top surface 40 so that the lower end of the lifting pin can rotate.
A process for constructing a reinforced earth retaining wall with blocks according to the present invention includes the steps of: digging trenches for footing and then casting footing concrete in order to construct the footing; placing blocks on the cast footing in a horizontal direction so that they are adjacent to one another and stacking and aligning another block on each block placed horizontally using a vertical connecting pin P′ in order to install the blocks; and arranging reinforcement members on a reinforced earth and filling and compacting the reinforced earth placed in the rear of the installed block with soil. Specifically, to perform the last step, a leading edge of each reinforcement member is inserted into a reinforcement member insertion groove to thereby connect the reinforcement member to the block, and the reinforcement members are arranged on the reinforced earth. Then, the reinforcement members arranged on the reinforced earth are backfilled and compacted with soil.
Furthermore, even where the intermeshing portions 32 and 32′ on the left and right sides of the block B are not parallel to but inclined to each other at a predetermined angle, it is possible to prevent the reinforced earth G from being carried away from the rear of the block B and still maintain the clamping between the intermeshing portions 32 and 32′ since the three faces on either side of the block B contact one another.
As shown in the cross-sectional view of
Since the retaining wall constructed using the blocks of the present invention is designed to prevent interlocking or crossing between horizontally adjacent blocks, where damage occurs to a block belonging to one of rows of retaining wall blocks, it is possible to disassemble only the row containing the damaged block downward in a sequential order, remove the damaged block, and reconstruct the new block. This allows a quick repair work with less labor in a space-limited workplace compared to a conventional repair process that has involved extensively dissembling blocks or panels in order to replace the damaged block or panel in a conventional block or panel-type retaining wall. Where many rows of blocks are damaged, as shown in
Also in this embodiment, a connecting pin insertion hole h1 for pinning upper and lower blocks with a connecting pin and a lifting pin insertion hole h2 for simultaneously lifting the blocks penetrate through the top and bottom surfaces 40 and 50. The block of this embodiment can be realized as a lightweight block by further including reinforcement member insertion grooves 44 and 54 separately formed vertically with respect to the partition wall 55. In order to reduce earth pressure exerted on the block, an upper portion of the rear surface 20 contacting with a reinforced earth has a reinforcement member insertion groove 44 with the upper surface sloping downward and rearward. The reinforcement member insertion groove 54 formed at the lower portion of the partition wall 55, has a top surface, corresponding to the bottom surface of the partition wall 55, made horizontal in order to enable block formation.
Referring to
Also, the block of this embodiment includes anther assembling protrusion 42′ and assembling recess 52′ at the middle portions of the top and bottom surfaces 40 and 50, respectively. In this case, the assembling recess 52′ is formed at the location corresponding to that of the assembling protrusion 42′. Elongated connecting pin Insertion holes h1 and h3 for inserting a connecting pin P′ that connects upper and lower blocks penetrate through the assembling protrusions 42 and 42′ and assembling recesses 52 and 52′
An elongated lifting pin insertion hole h2 is formed vertically between assembling protrusions 42 and 42′ or between assembling recesses 52 and 52′ in such a way as to lift blocks. A small groove (not shown) is formed around the lower rim of the lifting pin insertion hole h2 for hooking a projection positioned in the lower end of a lifting pin P″. To lift up the stacked blocks, the lifting pin P″ is inserted and turned at angle of 90 degrees so that the lower end of the lifting pin P″ is hooked into the locking groove.
Reference numbers 60, 70, and 80 denote a reinforcement member, a non-woven drainage filter made installed between adjacent courses of blocks, and a clamp for temporarily fixing the block, respectively.
As shown in
To make upward or downward sliding of the fixture pin P easier, it is preferable to vertically install a metal panel (not shown) on the rear surfaces of the fixture grooves 46 and 46 and to apply a lubricant, such as grease, thereto, followed by inserting the fixture pin P.
As shown in
A method for constructing a retaining wall with the block of this embodiment is the same as the first embodiment, and a detailed explanation thereof will not be given.
Since the block of this embodiment has assembling protrusion 42 and assembling recess 52 formed on the top and bottom surfaces 40 and 50, respectively, it is possible to construct the block correctly by engagement between the protrusion 52 and the recess 52 while maintaining an erection of retaining wall without a separate clamp during installation of a block, thereby enhancing convenience and safety during construction. A vertical connecting pin P′ can be inserted when necessary for assembling between upper and lower blocks to improve structural soundness during or after construction.
The block of this embodiment is used to construct various types of retaining walls using the above construction method. For example, several blocks grouped together into a single unit may be prefabricated into a single panel. As shown in
Since the retaining wall of the invention experiences no interference between horizontally adjacent blocks, in the event where partial repair is intended, it is possible to replace the damaged block with a new one by lifting up only overlying blocks of the damaged block, the overlying blocks belonging to a row containing the damaged block. Furthermore, it is easy to separate the reinforcement member from the block by lifting a fixture pin out of the fixture pin insertion groove formed in a top surface of the block without disassembling or carrying away the reinforced earth structure. To lift up the blocks, the lifting pin P″ as shown in
The block according to the illustrative embodiment is basically similar to that according to the third embodiment, and an explanation of the similar portions will not be given.
The block according to the illustrative embodiment is configured such that a recessed portion 12 is further formed inward with respect to the front surface 10. A top surface 12a and a bottom surface 12b of the recessed portion 12 slope upward with respect to a front, upper portion of the block, as shown in
The block according to the illustrative embodiment is characterized in that it allows growth of vegetation. In detail, as shown in
The left and right sides 30 and 30′ are formed rearward from the left and right of the front surface 10 toward the rear surface 20 and have intermeshing portions 32 and 32′ for connecting adjacent blocks in an intermeshed fashion. The top surface 40 includes a crosswise assembling projection 42, a reinforcement member insertion groove 44 and a fixture groove 46. The crosswise assembling projection 42 connects upper and lower blocks with each other in an intermeshed fashion. The reinforcement member insertion groove 44 is formed in a front-to-rear direction in which a leading edge of the reinforcement member buried inside a reinforced earth structure or a reinforcement member connecting anchor is inserted. The fixture groove 46 is formed in the left and right of the reinforcement member insertion groove 44, and the reinforcement member or the anchor is inserted into the fixture groove 46. The bottom surface 50 includes a crosswise assembling groove 52, a reinforcement member insertion groove 54, a vertical wall 57 and a partition wall 55. The crosswise assembling groove 52 is recessed at a location corresponding to the crosswise assembling projection 42 of the top surface 40. The reinforcement member insertion groove 54 is formed at a location corresponding to the reinforcement member insertion groove 44. The vertical wall 57 extending from the reinforcement member insertion groove 44 is formed between the reinforcement member insertion grooves 44, 54. The partition wall 55 is formed between the reinforcement member insertion grooves 44 and 54 in a left-to-right direction ranging from the front surface to the rear surface 20.
In the block according to this embodiment, among insertion holes h1, h2 formed at interconnections of the assembling projections 42 and the assembling grooves 52 formed on the top and bottom surfaces 40 and 50, respectively, the centrally located one is shaped of a slot elongated in a front-to-rear direction to be used to insert upper and lower connecting pins P′ (see
As shown in
As shown in
Also, the intermeshing portions 32 and 32′ of the left and right sides 30 and 30′ of the blocks are not limited to those forming a straight line connecting the blocks. Rather, the intermeshing portions 32 and 32′ may connect adjacent blocks at angles adapted to the geographical features of the construction site, thereby constructing a curved retaining wall without carrying away the reinforced earth structure or exposing the reinforced earth structure.
Also, the partition wall 55 is not parallel with the bottom but slopes toward the front, upper portion of the block B, that is, toward the rear, lower portion of block B. Thus, the block B itself is durable against damage due to a vertical shearing force. Also, when the upper and lower blocks are stacked, a latticed rigid structure can be formed.
Since the partition wall 55 slopes upward with respect to the front, upper portion of the block, as shown in
Preventing the upper and lower blocks from slipping during or after construction can be ensured by a connecting power established inserting the upper and lower connecting pins P′ into the connecting holes h1, as well as by an intermeshed connection between the assembling projection 42 and the assembling groove 52 formed on the top and bottom surfaces 40 and 50. Also, the blocks can be prevented from turning upside down or leaning, that is, collapse can be avoided.
The top and bottom surfaces of the partition wall 55 and sides of the vertical walls 47 and 57 are shaped of uneven waveforms, as shown in
In an event of subsidence of reinforced earth structure G, the retaining wall with the blocks according to the present invention primarily vertically slides along a leading edge of a reinforcement member 60 or an anchor 110 buried inside the reinforced earth structure G, or a fixture groove 46 vertically formed on a top surface 40 of a block B, and secondarily rotates and falls along a reinforcement member insertion groove 44. Thus, subsidence power of the reinforced earth structure G is not directly transferred to the block B, causing a small amount of displacement of the block B, thereby keeping the retaining wall at a stable construction state in spite of subsidence of the reinforced earth structure G.
Also, some of the earth pressure of the reinforced earth structure G is applied to the retaining wall structure (block) is absorbed in the box-shaped space formed by the reinforcement member insertion grooves 44 and 54 horizontally penetrating the block B. That is, the earth pressure of the reinforced earth structure G is applied to vegetative earth G′ filled in the box-shaped space formed by the reinforcement member insertion grooves 44 and 54, rather than totally being applied to the block B. Then, the vegetative earth G′ is slightly pushed frontward and the earth pressure is absorbed in the box-shaped space. Thus, bulging of the retaining wall structure can be prevented and the earth pressure exerted on the wall can be reduced, thereby effectively suppressing various kinds of displacement, including bulging, of the wall structure.
The block according to the present invention is simply intermeshed with horizontally adjacent blocks at its lateral surfaces. Thus, in the event where the block is partially damaged, it is possible to replace the damaged block with a new one after sequentially lifting up only overlying blocks belonging to a row containing the damaged block, while leaving the horizontally adjacent blocks intact. Furthermore, a repair or reinforcement work can be facilitated without disturbing the reinforced earth structure in the rear of the retaining wall.
As shown in
As shown in
To impart the respective unit blocks B with a granite-like texture, cement, sand, stone powder and other aggregate are mixed at an appropriate mixing ratio, and the resulting mixture is poured into a mold for compressive formation. In a state in which front surfaces 10 of the respective unit blocks B contact each other, the mold is cut by a slicer so that the front surfaces 10 are naturally configured to simulate granite or another stone. Also, the front surfaces 10 of the respective unit blocks B may be formed with various patterns including an arc or waveform, instead of a linear pattern.
The unit block B, as shown in
The insertion portion 5 is formed at lower edges of either side of the unit block B in such a way as to be opened laterally and downward. The locking groove 6 has substantially the same shape with that of the insertion portion 5, and has a horizontally elongated, elliptical groove 6a extending downward so that both ends of the fixture element L are inserted thereinto to be hooked thereon.
As shown in
Also, a closely adhering surface 31, to which a support plate S of a clamp C is closely adhered, is formed at either side of the rear surface 20 of the unit block B. The clamp C temporarily fixes adjacent panels by locking the fixture element L.
The unit block B has the front surface 10 and the rear surface 20 stepped not only vertically but also horizontally, as shown in
As shown in
In the retaining wall constructed using panels according to the present invention, the fixture element L allows horizontally adjacent panels A to be spaced a predetermined distance apart from each other, rather than being adhered to or separated from each other or, which is called an interlocked state. Upper and lower panels A that are vertically stacked are also spaced apart from each other by a predetermined distance, thereby improving resistance against vibration or other external forces.
As shown in
In the panel A according to the present invention, a leading edge of the reinforcement member 60 is connected to a connecting element P′ inserted into the panel A by a locking element 62 so that the panel A is disposed rearward and a reinforced earth structure (not shown) is laid and compacted, thereby supporting the retaining wall. Useful examples of the is reinforcement member 60 include conventional geogrid, galvanized steel plate, band-shaped synthetic resin reinforcing fiber and so on. A reinforcement member can be connected to any portion of a panel, and any reinforcement members are connectable according to conditions of a construction site or construction design.
The reinforcement member 60 of this embodiment includes a pair of panel-shaped locking elements 62, a reinforcing plate 66, and resistors 68. The pair of panel-shaped locking elements 62 are engaged with a connecting element P′ connecting vertically stacked unit blocks B through a rectangular hole formed by channels 1 formed between the stacked unit blocks B. A leading edge of the reinforcing plate 66 is engaged to a locking element 62 by a bolt 64 and a nut 65. The resistors 68 are spaced a predetermined interval from each other and attached at right angle along the length of the reinforcing plate 66. Preferably, the reinforcement member 60 of this embodiment is of a continuous type, in which a plurality of metal reinforcing plates 66 are installed in parallel with each other, and rod-shaped metal resistors 68 are welded at a predetermined interval along the length of the reinforcing plates 66, as shown in the left of
As shown in
As shown in
In the present invention, a fixture element L is fabricated by bending a steel bar in a bottom-opened rectangular () shape. Both ends of the fixture element L, which are bent downward, are inserted into grooves 6a of the locking groove 6 through an insertion portion 5 formed at upper and lower portion on both sides of a unit block B forming a panel A. A temporary fixing clamp C is hooked on a middle portion of the fixture element L inserted into the locking groove 6 of the unit block B forming an adjacent panel A and tightened by a nut N, so that a support plate S is closely adhered to a closely adhering surface 31 in the rear of the unit block B, thereby maintaining a firmly interlocked state between adjacent panels.
As shown in
A method of constructing a reinforced earth retaining wall using prefabricated panel according to a ninth embodiment of the present invention will now be described.
The method includes steps of panel assembling, adjusting, finishing, interlocking, arranging and assembling, and compacting. In the panel assembling step, two or four unit blocks B, formed at factories, are stacked to be fabricated a two-tier panel (A1) or four-tier panel (A2) using connecting elements P′ and connecting means 12′.
In the adjusting step, prefabricated panels, reinforcement members and other materials including fixture elements, temporary fixing clamps and so on, are transported to a construction site, and the site is digged to be wide enough for installation of reinforcement members.
In the finishing step, footing concrete having a width of about 40 cm and a height of about 20 to 25 cm is cast at a place where panels are to be installed, and the top surface of the footing concrete is planarized.
In the interlocking step, panels A are transported from the warehouse and placed on the footing, and adjacent panels are interlocked such that a fixture element L is inserted into a locking groove 6 through an insertion portion 5 formed on a unit block B forming each panel A, and a temporary fixing clamp C is locked on the fixture element L in the rear of the panel to be engaged.
In the arranging and assembling step, another panels A are sequentially rested on the panels to interlock adjacent panels using the fixture element L, and reinforcement members is arranged in a horizontal direction in the rear of the panels A.
In the compacting step, a reinforced earth structure is applied over the horizontally arranged reinforcement members, followed by compacting.
In the construction method according to the present invention, prefabricated panels are lifted up using equipment and sequentially piled up. Here, the lifting is performed using a lifting hook of a crane engaged with a connecting element P′ projecting at an upper portion of the prefabricated panel. The lifted panel is released at a stacked position, while shock-absorbing pad 14 is inserted between upper and lower panels to maintain a predetermined distance therebetween and to absorb a shock. When the prefabricated panel is placed at an accurate position, it is interlocked with an adjacent panel. In this case, the fixture element L is inserted through the insertion portion 5 opened laterally from the side of the panel to be fitted into the fixture groove 6. In this state, the temporary fixing clamp C is hooked on a middle portion of the fixture element L inserted into the locking groove 6 and tightened by the nut N, so that a support plate S is closely adhered to a closely adhering surface f7 in the rear of the unit block B forming the panel, thereby maintaining a firmly interlocked state between adjacent panels so as to be vertically supported.
Inserting the fixture element and engaging the temporary fixing clamp makes horizontally adjacent panels spaced a predetermined distance apart from each other and making the surface of a retaining wall constructed by the panels even. Also, upper and lower panels are vertically supported by an interlocking action by the fixture element and the temporary fixing clamp, thereby installing panels in a stable manner even before a reinforcement member is constructed.
Further, according to the present invention, concentration of stress can be prevented from occurring at a connected portion of the fixture element by the characteristic interlocking action of the fixture element, thereby improving resistance of the retaining wall against vibration or differential subsidence which may occur after construction of the retaining wall is completed.
After the installing work of the panel is completed, a reinforcement member is connected to a rear portion of the panel, and a reinforced earth structure is applied over the resulting structure to then be compacted. The prefabricated panel according to the present invention does not have an anchor projecting on the rear portion thereof. Instead, the connecting element P′ vertically inserted into the panel serves as an anchor. Thus, small-sized compacting equipment is easily accessible, so that a compacting work of a reinforced earth structure can be perfectly carried out even at a portion close to the rear surface of the panel.
The locking element 62′ shown in
In the above-described embodiments of the present invention, when the reinforcement members buried inside the reinforced earth structure are connected to blocks forming a front wall surface of the retaining wall, distances among the reinforcement members arranged vertically and horizontally can be freely adjusted according to design variations depending on construction site conditions. According to the present invention, since multiple blocks are formed by a single mold, the productivity is high, the manufacturing cost is low and manageability of formed blocks is also ensured, compared to the conventional various type panels.
INDUSTRIAL APPLICABILITYAccording to the present invention, since a hollow or space is formed in a block itself in a direction in which it contacts a reinforced earth structure, the block can be made lightweight, allowing a reduction in material cost and easy transportation, thereby providing excellent workability compared to the conventional panel for construction a retaining wall. Also, the block according to the present invention can be installed more easily and safely than the conventional block. Even if there is displacement occurring to reinforced earth structure after construction, a connected portion of a leading edge of a reinforcement member subsides while primarily sliding vertically and secondarily rotating, thereby preventing deformation of the retaining wall or disconnection of the reinforcement member, ensuring high durability. Since horizontally adjacent blocks are in an intermeshed state with each other, rather than in an interlocked state, only partial damage due to differential subsidence of the reinforced earth structure or ground, if any, can be easily repaired by sequentially disassembling only blocks belonging to a row containing the damaged portion to be reconstructed, without adversely affecting the reinforced earth structure. Further, since a relatively large area of lower and upper portions of the retaining wall is used for landscaping, roots of plants can extend well toward the reinforced earth structure. Since the upper and lower portions of the retaining wall have a capacity of holding reinforced earth and water, the retaining wall can provide an excellent efficiency in growth of vegetation growth even in an area having insufficient raindrop. According to another aspect of the present invention, an interlocking action between adjacent panels allows a vertical supporting structure to be achieved just by installing prefabricated panels, thereby preventing the retaining wall from collapsing or overturning during construction. In an event of subsidence of a reinforced earth structure, a locking element configured to be slidable downward, can prevent concentration of stress. Also, since an anchor is not exposed in the rear of the panel, small-sized compacting equipment is easily accessible to the rear surface of the panel, thereby perfectly carrying out a compacting work. Thus, defects, which may be produced after the construction is completed, can be prevented. When localized defects are produced after the construction is completed, panels forming the retaining wall can be partially disassembled just by releasing an interlocked state of adjacent panels, thereby facilitating a local repair work.
Claims
1. A block for constructing a retaining wall comprising:
- a front surface 10 forming a surface of the retaining wall, and a rear surface 20 contacting a reinforced earth structure;
- left and right sides 30 and 30′ having corresponding intermeshing portions 32 and 32′ formed thereon for intermeshed connection between adjacent blocks, respectively;
- a top surface 40 having reinforcement member insertion grooves 44 formed in a front-to-rear direction, into which a reinforcement member or an anchor for connecting the reinforcement member is fitted and fixture grooves 46 formed on either side of the front of the reinforcement member insertion grooves 44 for fixing the reinforcement member or anchor; and
- a bottom surface 50 corresponding to the top surface 40, wherein a connecting pin insertion hole h1 for pinning upper and lower blocks with a connecting pin and a lifting pin insertion hole h2 for simultaneously lifting the upper and blocks, penetrate through the top and bottom surfaces 40 and 50.
2. The block of claim 1, wherein a hollow H penetrating the top and bottom surfaces 40 and 50 thereof is formed.
3. The block of claim 1 or 2, wherein the connecting pin insertion pins h1 are formed on either side of the top and bottom surfaces 40 and 50, lifting pin insertion holes h2 are formed at the center thereof in consideration of the center of gravity during lifting, an extension groove h2′ having a larger diameter is formed around the lifting pin insertion hole h2 on the top surface 40 so that the lower end of the lifting pin can rotate.
4. The block of claim 1, wherein a partition wall 55 is formed at the center of the rear surface 20, the partition wall 55 horizontally extending both rearward from the rear portion of the front surface 10 and horizontally, so that reinforcement member insertion grooves 44 and 54 are separately formed vertically with respect to the partition wall 55.
5. The block of claim 4, wherein the upper surface of the partition wall 55 slopes downward and rearward.
6. A block for constructing a retaining wall comprising:
- a front surface 10 forming a surface of a retaining wall, and a rear surface 20 contacting a reinforced earth structure;
- left and right sides 30 and 30′ formed rearward toward the rear surface 20 at left and right sides of the front surface 10, and having intermeshing portions 32 and 32′ for intermeshed connection between adjacent blocks at their front portions, and narrow portions stepped with the intermeshing portions 32 and 32′ at their rear portions;
- a top surface 40 having assembling protrusions 42 and 42′ formed on the front and middle portions thereof, reinforcement member insertion grooves 44 formed in the rear portion in a front-to-rear direction, into which a reinforcement member or an anchor for connecting the reinforcement member is fitted, and fixture grooves 46, into which a fixture pin P for fixing the reinforcement member or anchor is inserted, formed on either side of front of the reinforcement member insertion groove 44 in such a way as to be opened toward the left and right sides 30 and 30′; and
- a bottom surface 50 having assembling recesses 52 and 52′ recessed at its front and middle portions to be located at positions corresponding to the assembling protrusions 42 and 42′ formed on the top surface 40, and reinforcement member insertion grooves 54 and fixture grooves 56 formed at its rear portion corresponding to the counterparts 44 and 46 of the top surface 40.
7. The block of claim 6, wherein anther assembling protrusion 42′ and assembling recess 52′ are formed at the middle portions of the top and bottom surfaces 40 and 50, respectively, the assembling recess 52′ is formed at the location corresponding to that of the assembling protrusion 42′, elongated connecting pin Insertion holes h1 and h3 for inserting a connecting pin P′ that connects upper and lower blocks penetrate through the assembling protrusions 42 and 42′ and assembling recesses 52 and 52′, an elongated lifting pin insertion hole h2 is formed vertically between assembling protrusions 42 and 42′ or between assembling recesses 52 and 52′ in such a way as to lift blocks, and a small groove is formed around the lower rim of the lifting pin insertion hole h2 for hooking a projection positioned in the lower end of a lifting pin P″.
8. The block of claim 6 or 7, wherein a recessed portion 12 is further formed inward with respect to the front surface 10, and a top surface 12a and a bottom surface 12b of the recessed portion 12 slope upward with respect to a front, upper portion of the block, the recessed portion 12 being led to reinforcement member insertion grooves 44, 54 of the rear surface 20 of the block.
9. A block for constructing a retaining wall comprising:
- a front surface 10 forming a surface of the retaining wall and a rear surface 20 contacting a reinforced earth structure;
- left and right sides 30 and 30′ formed rearward from the left and right of the front surface 10 toward the rear surface 20 and having intermeshing portions 32 and 32′ for connecting adjacent blocks in an intermeshed fashion;
- a top surface 40 having a crosswise assembling projection 42 connecting upper and lower blocks with each other in an intermeshed fashion, a reinforcement member insertion groove 44 formed in a front-to-rear direction in which a leading edge of the reinforcement member buried inside a reinforced earth structure or a reinforcement member connecting anchor is inserted, and a fixture groove 46 formed in the left and right of the reinforcement member insertion groove 44, and into which the reinforcement member or the anchor is inserted into; and
- a bottom surface 50 having a crosswise assembling groove 52 recessed at a location corresponding to the crosswise assembling projection 42 of the top surface 40, a reinforcement member insertion groove 54 formed at a location corresponding to the reinforcement member insertion groove 44, a vertical wall 57 extending from the reinforcement member insertion groove 44 and formed between the reinforcement member insertion grooves 44 and 54, and a partition wall 55 formed between the reinforcement member insertion grooves 44 and 54 in a left-to-right direction ranging from the front surface to the rear surface 20.
10. The block of claim 9, wherein connecting pin and lifting pin insertion holes h1 and h2 are formed at interconnections of the assembling projections 42 and the assembling grooves 52 formed on the top and bottom surfaces 40 and 50, respectively, the lifting pin insertion hole h2 is shaped of a slot elongated in a front-to-rear direction, and an internal locking portion 52a is formed in the assembling groove 52 formed on the bottom surface 50 of the block in the left-to-right direction so that a lifting pin P″ is hooked therein.
11. The block of claim 9 or 10, wherein front faces of upper and lower reinforcement member insertion grooves 44 and 54 are closed by blocking walls 44a and 54a.
12. A prefabricated reinforced earth retaining wall constructed using the block claimed in any one of claims 1, 2, 4, 5, 6, 7, 9 and 10.
13. A method for constructing a retaining wall using the block claimed in any one of claims 1, 2, 4, 5, 6, 7, 9 and 10, the method comprising:
- digging trenches for footing and then casting footing concrete in order to construct the footing;
- placing blocks on the cast footing in a horizontal direction so that they are adjacent to one another and stacking and aligning another block on each block placed horizontally using a vertical connecting pin P′ in order to install the blocks; and
- arranging reinforcement members on a reinforced earth structure and filling and compacting the reinforced earth placed in the rear of the installed block with soil, such that a leading edge of each reinforcement member is inserted into a reinforcement member insertion groove to thereby connect the reinforcement member to the block, the reinforcement members are arranged on the reinforced earth, and then, the reinforcement members arranged on the reinforced earth are backfilled and compacted with soil.
14. A method for repairing a reinforced earth retaining wall constructed by the method claimed in claim 13, the method comprising:
- lifting up blocks positioned above the damaged portion of a block, the blocks belonging to a row containing the damaged block, to disassemble the overlying block after lifting a reinforcement member fitted into a reinforcement member insertion groove and separating the same from the block;
- removing the damaged block after disassembling the overlying block;
- placing a new block at the location of the previously damaged block, inserting a vertical connecting pin, and fitting a leading edge of the reinforcement member buried inside a reinforced earth into a reinforcement member insertion groove of the new block in order to connect the reinforcement member to the block; and
- reversing the order of the above disassembling step to reconstruct the disassembled block.
15. The method of claim 14, where many rows of blocks are damaged, comprising:
- disassembling blocks positioned above rows containing the damaged blocks in a sequential order from one row to another;
- removing the damaged blocks after disassembling the overlying blocks;
- placing new blocks at locations of the previously damaged blocks, inserting vertical connecting pins, and fitting leading edges of the reinforcement members buried inside a reinforced earth structure into reinforcement member insertion grooves of the new blocks; and
- reversing the order of the above disassembling step to reconstruct the disassembled blocks.
16. A panel for a prefabricated block-type reinforced earth retaining wall comprising:
- a plurality of unit blocks B each unit including a front surface 10 forming an outer surface of a retaining wall, a rear surface 20 contacting a reinforced earth structure, a bottom surface 50 and a top surface 40 having a plurality of channels 1 and throughholes 2 vertically formed at a predetermined position of each channel 1, and left and right sides 30 and 30′ having an insertion portion 5 and a locking groove 6, creating a portion into which an insertion portion L for preventing the unit blocks B of an adjacent panel A from alienating from or getting close to each other by interlocking unit blocks B of the adjacent panel A, is inserted;
- connecting elements P′ inserted into the throughholes 2 in a state in which the plurality of unit blocks B are vertically stacked; and
- connecting means 12′ engaged with one end of the connecting element P′ and connecting the stacked plurality of unit blocks B with one another.
17. The panel of claim 16, wherein the fixture element L is in a bottom-opened rectangular () shape.
18. The panel of claim 16, wherein the insertion portion 5 is formed at lower edges of either side of the unit block B in such a way as to be opened downward and laterally, and the locking groove 6 has substantially the same shape with that of the insertion portion 5 the locking groove 6 having a horizontally elongated, elliptical groove 6a extending downward so that both ends of the fixture element L are inserted thereinto to be hooked thereon.
19. The panel of claim 18, wherein the insertion portion 5 and the locking groove 6 are configured to extend in a front-to-rear direction toward outside.
20. The panel of claim 16, wherein a closely adhering surface 31, to which a support plate S of a clamp C for fixing adjacent panels by locking the fixture element L is closely adhered, is formed at either side of the rear surface 20 of the unit block B.
21. A method for constructing a reinforced earth retaining wall using a prefabricated panel, comprising:
- assembling panels such that unit blocks B, formed at factories, are assembled using connecting elements P′ and connecting means 12′;
- transporting panels and placing the same on a footing of the retaining wall, and interlocking the panels A such that a fixture element L is inserted into a locking groove 6 through an insertion portion 5 formed on a unit block B forming each panel A, and a temporary fixing clamp C is locked on the fixture element L and tightened by a nut N in the rear of the panel A, thereby maintaining an interlocked state between the panels;
- sequentially resting another panels A on the panels to interlock adjacent panels using the fixture element L in the same manner as in the interlocking step, and arranging reinforcement members in a horizontal direction in the rear of the panels A; and
- applying a reinforced earth structure over the horizontally arranged reinforcement members and compacting.
Type: Application
Filed: Oct 28, 2003
Publication Date: Mar 9, 2006
Inventor: Jeung Lee (Kunpo-City, Kyungki-do)
Application Number: 10/535,889
International Classification: E02D 5/00 (20060101); E02D 17/00 (20060101);