JP6506986B2 - Bonding structure and method of precast concrete members - Google Patents

Description

  The present invention relates to, for example, a joint structure and a joint method of precast concrete members.

Conventionally, a concrete member is manufactured in advance in a factory, and this member (hereinafter referred to as a precast concrete member) is transported to a construction site and joined together to construct a building, a precast construction method is there.
In this construction method, when joining precast concrete members, the height of the precast concrete members is adjusted by providing a mortar in the gap between the precast concrete members, and transfer of the load between the precast concrete members is the entire joining surface (See Patent Document 1). Furthermore, the end face of the mortar on the outdoor side is filled with a sealing material to prevent the infiltration of rain water.

JP 2000-248614 A

However, since the service life of the seal material is about 10 years, when the seal material reaches near the service life, the seal material may be broken and rainwater may enter between the seal material and the precast concrete member. . In addition, there is a case where rainwater infiltrates between the mortar and the precast concrete member only with the mortar of the gap between the precast concrete members. As a result, rainwater may enter the room.
In order to solve this problem, it is necessary to regularly rework the sealing material, but there is a problem that the cost is increased.

  An object of this invention is to provide the joining structure and joining method of a precast-concrete member which can prevent rain water from entering indoors at low cost.

  The joint structure (for example, joint structure 1, 1A, 1B described later) of the precast concrete member according to claim 1 is an outer end (for example, the second floor surface 2 described below) of a concrete floor (for example, A joint structure in which a wall member made of precast concrete (for example, a second floor wall member 30 described later) is joined to an outer end portion 3 described later, between the outer end portion of the floor surface and the lower surface of the wall member A mortar layer (for example, a mortar layer 42 described later) is formed, and a silicate (for example, a silicate 41 described later) is applied to the outer end of the floor surface and the lower surface of the wall member. And / or silicate is mixed in the mortar layer.

  Here, the silicate is, for example, a mixture of sodium silicate and calcium silicate, or sodium silicate.

  According to this invention, the silicate was applied to the outer end of the floor surface and the lower surface of the wall member. Alternatively, the mortar layer was mixed with silicate. By reacting with water to gelate, the silicate blocks water (cracks) and voids, which are paths of the water, and exhibits waterproof performance. Therefore, when the water in the mortar layer or the rainwater that has penetrated into the mortar layer comes in contact with the silicate, the passage of the water is blocked by the silicate, so that the rainwater can be prevented from entering the house at low cost.

The joint structure of the precast concrete member according to claim 1 is characterized in that the outer end of the floor surface is formed with an inclined surface (for example, an inclined surface 4 described later) which is lowered toward the outdoor side. .

  According to this invention, the inclined surface which falls as it goes to the outdoor side was formed in the outer end part of the floor to which the wall member of a precast-concrete structure is joined. Therefore, even if rainwater infiltrates the mortar layer and reaches the slope, this rainwater flows on the slope and is drained to the outside. Thus, rainwater can be more reliably prevented from entering the room.

The joint structure of the precast concrete member according to claim 2 is characterized in that a slope of the inclined surface is approximately 1/50 or more.

  According to the present invention, since the slope of the inclined surface is approximately 1/50 or more, the rainwater on the inclined surface can be drained by reliably flowing downward along the inclined surface.

The joint structure of the precast concrete member according to claim 3 (for example, a joint structure 1A described later), the mortar layer (for example, a mortar layer 42A described later) is a first mortar layer (for example, a first mortar layer described later) 50) and a second mortar layer (for example, a second mortar layer 51 described later) provided on the outdoor side of the first mortar layer.

  According to this invention, since the second mortar layer is provided on the outdoor side of the first mortar layer, rainwater penetrates the second mortar layer and reaches the interface between the first mortar layer and the second mortar layer. Even then, the rainwater moves downward along this boundary surface to reach the slope, and flows on the slope and is drained to the outside. Therefore, rainwater can be more reliably prevented from entering the room.

The joint structure (for example, joint structure 1B described later) of the precast concrete member according to claim 4 is added to the mortar layer between the outer end of the floor and the lower surface of the wall member, A backup material (for example, a backup material 61 described later) provided on the outdoor side of the mortar layer, and a sealing material (for example, a sealing material 60 described later) disposed on the outdoor side of the backup material; A groove (for example, a groove 62 described later) extending along the outer periphery is formed immediately below the backup material at an outer end portion of the floor surface.

  According to this invention, the backup material is provided on the outdoor side of the mortar layer, and the seal material is placed on the outdoor side of the backup material. Further, a groove extending along the outer periphery was formed immediately below the backup material. Therefore, when the rainwater penetrates the sealing material and reaches the backup material, the rainwater moves downward to reach the groove and flows through the groove and is drained to the outside. Therefore, rainwater can be more reliably prevented from entering the room.

The joint structure of the precast concrete member of the present invention (for example, joint structure 1C described later) is a joint structure in which a wall member made of precast concrete is jointed to the outer end of the floor of concrete, At the end, a stepped upper surface (for example, a stepped upper surface 70 described later) and a stepped lower surface (for example, a stepped lower surface 71 described below) provided on the outdoor side of the stepped upper surface and lower than the stepped upper surface A mortar layer is formed between the outer end of the floor and the lower surface of the wall member, and a silicate is applied to the outer end of the floor and the lower surface of the wall member. And / or preferably, the mortar layer is mixed with a silicate .

  Here, the silicate is, for example, a mixture of sodium silicate and calcium silicate, or sodium silicate.

  According to this invention, the silicate was applied to the outer end of the floor surface and the lower surface of the wall member. Alternatively, the mortar layer was mixed with silicate. By reacting with water to gelate, the silicate blocks water (cracks) and voids, which are paths of the water, and exhibits waterproof performance. Therefore, when the water in the mortar layer or the rainwater that has penetrated into the mortar layer comes in contact with the silicate, the passage of the water is blocked by the silicate, so that the rainwater can be prevented from entering the house at low cost.

  Moreover, the upper surface of the step and the lower surface of the step were formed at the outer end of the floor surface to which the wall member made of precast concrete is joined. Therefore, even if rainwater penetrates the mortar layer and reaches the lower surface of the step, the rainwater does not reach the upper surface of the step, and is drained to the outside. Thus, rainwater can be more reliably prevented from entering the room.

The joint structure (for example, joint structure 1D described later) of the precast concrete member of the present invention is a joint structure for joining the side surfaces of a floor member (for example, floor member 80 described later) made of precast concrete, A mortar layer (for example, a mortar layer 82 described later) is formed between the side surfaces, and a silicate (for example, a silicate 81 described later) is applied to the side surface of the floor member, and Preferably, silicate is mixed in the mortar layer .

  Here, the silicate is, for example, a mixture of sodium silicate and calcium silicate, or sodium silicate.

  According to this invention, the silicate was applied to the side of the floor member. Alternatively, the mortar layer was mixed with silicate. By reacting with water to gelate, the silicate blocks water (cracks) and voids, which are paths of the water, and exhibits waterproof performance. Therefore, when the water in the mortar layer or the rainwater that has penetrated into the mortar layer comes in contact with the silicate, the passage of the water is blocked by the silicate, so that the rainwater can be prevented from entering the house at low cost.

A joining method according to claim 5 is a joining method for joining a precast concrete wall member to an outer end of a concrete floor, the outer end of the floor and the lower surface of the wall being A step of applying a silicate (eg, steps S1, S2, S11, S12 described below), and a step of depositing mortar on the outer end of the floor surface (eg, steps S3, S13 described below) And mounting the wall member on the outer end of the floor surface (e.g., steps S4 and S14 described later).

  According to the present invention, the same effects as those of the first aspect described above can be obtained.

A joining method according to claim 6 is a joining method of a precast concrete member for joining a precast concrete wall member to an outer end portion of a concrete floor surface, wherein the joining method is performed on the outer end portion of the floor surface. A step of depositing a mortar mixed with a silicate (for example, steps S21 and S22 described later) and a step of mounting the wall member on an outer end of the floor surface (for example, a step S23 described below) And.

  According to the present invention, the same effects as those of the first aspect described above can be obtained.

  According to the invention, the outer edge of the floor and the underside of the wall member are coated with silicate. Alternatively, the mortar layer was mixed with silicate. By reacting with water to gelate, the silicate blocks water (cracks) and voids, which are paths of the water, and exhibits waterproof performance. Therefore, when the water in the mortar layer or the rainwater that has penetrated into the mortar layer comes in contact with the silicate, the passage of the water is blocked by the silicate, so that the rainwater can be prevented from entering the house at low cost.

It is a perspective view of a part of building of wall type precast concrete structure where junction structure of precast concrete members concerning a 1st embodiment of the present invention was applied. It is an expanded sectional view of the part enclosed with the broken line of FIG. It is a flowchart of the procedure which builds the joint structure of the precast-concrete member which concerns on the said embodiment. It is a perspective view for demonstrating the procedure which builds the joining structure of the precast-concrete member which concerns on the said embodiment. It is an expanded sectional view of the bonded structure of the precast-concrete member which concerns on 2nd Embodiment of this invention. It is an expanded sectional view of the bonded structure of the precast-concrete member which concerns on 3rd Embodiment of this invention. It is an expanded sectional view of the bonded structure of the precast-concrete member which concerns on the 1st reference example of this invention. It is an expanded sectional view of the bonded structure of the precast-concrete member which concerns on the 2nd reference example of this invention. It is a flowchart of the procedure of constructing the joint structure of the precast-concrete member which concerns on the 1st modification of this invention. It is a flowchart of the procedure of constructing the bonded structure of the precast-concrete member which concerns on the 2nd modification of this invention. It is a schematic diagram which shows the structure of an experiment apparatus. It is a figure which shows experimental conditions and an experimental result.

Hereinafter, embodiments of the present invention will be described based on the drawings. In the description of the embodiments below, the same components will be denoted by the same reference numerals, and the description thereof will be omitted or simplified.
First Embodiment
FIG. 1 is a perspective view of a part of a wall-type precast concrete structure to which a joint structure 1 of precast concrete members according to a first embodiment of the present invention is applied. FIG. 2 is an enlarged sectional view of a portion surrounded by a broken line in FIG. Here, FIGS. 1 and 2 show the joint between the first floor member 10, the second floor member 20, and the second floor member 30. As shown in FIG.

  The first floor wall member 10 is a plate-like member made of precast concrete, and extends substantially vertically to become a first floor outer peripheral wall. The second floor member 20 is a plate member made of precast concrete, and extends substantially horizontally to be a second floor. The second floor wall member 30 is a plate-like member made of precast concrete, and extends substantially vertically to become a second floor outer peripheral wall.

  The second floor member 20 is joined to the upper end portion of the first floor wall member 10, and the upper surface of the second floor member 20 and the upper end face of the first floor member 10 form the second floor surface 2. The second floor wall member 30 is joined to the outer end 3 of the floor surface 2. Here, the outer end 3 of the second floor 2 to which the second floor wall member 30 is joined is an inclined surface 4 which is lowered toward the outdoor side. The slope of this inclined surface 4 is approximately 1/50.

Hereinafter, the structure of the joint between the first floor wall member 10, the second floor member 20, and the second floor member 30 will be described in detail.
The upper end surface of the first floor wall member 10 is an inclined surface 10A. Further, on the inner end side of the upper end face of the first floor wall member 10, a notch 11 including a bottom surface 12 and a wall surface 13 is formed.

Further, at the outer end of the second floor member 20, an inclined surface 20A is formed. The outer end of the second floor member 20 is locked to the bottom surface 12 of the notch 11 of the first floor wall member 10, and the side end face of the second floor member 20 and the wall surface 13 of the notch 11 The mortar 40 is filled in the interstices of.
Thereby, the inclined surface 10A of the first floor wall member 10 and the inclined surface 20A of the second floor member 20 are integrated to form the inclined surface 4.

A silicate 41 is applied to the slope 4 of the second floor 2 and the lower surface of the second floor member 30.
Further, mortar is filled between the inclined surface 4 of the second floor 2 and the lower surface of the second floor member 30 to form a mortar layer 42.

Next, the procedure of constructing the joint structure 1 of the precast concrete member will be described with reference to the flowchart of FIG.
In step S1, the first floor wall member 10 is erected, the floor member 20 is engaged with the notch 11 of the first floor wall member 10, and the space between the second floor member 20 and the first floor wall member 10 is mortared. Fill 40 Thereby, the second floor member 20 is joined to the first floor wall member 10 to form the second floor surface 2, and the inclined surface 4 is formed at the outer end 3 of the second floor surface 2.

In step S 2, the silicate 41 is applied on the outer end 3 of the second floor 2, that is, the inclined surface 4, and the silicate 41 is applied on the lower surface of the second floor member 30.
At step S 3, mortar 43 is deposited on the outer end 3 of the second floor 2.
In step S4, the second floor wall member 30 is suspended from above and placed on the outer end 3 of the second floor 2 as indicated by the white arrow in FIG. Then, the deposited mortar 43 is filled between the outer end 3 of the second floor 2 and the second floor wall member 30 to form a mortar layer 42, and the second floor wall member 30 is the outer end of the second floor 2. It is joined to the part 3.

According to the present embodiment, the following effects can be obtained.
(1) The silicate 41 was applied to the outer end 3 of the second floor 2 and the lower surface of the first floor member 10. By reacting with water to gelate, the silicate blocks water (cracks) and voids, which are paths of the water, and exhibits waterproof performance. Therefore, when the moisture in the mortar layer 42 or the rainwater that has penetrated into the mortar layer 42 touches the silicate 41, the passage of water is blocked by the silicate 41, and therefore rainwater can enter the room at low cost. Can prevent it.

  (2) The inclined surface 4 which falls as it goes to the outdoor side was formed in the outer end part 3 of the 2nd floor floor 2 to which the 2nd floor wall member 30 of a precast concrete structure is joined. Therefore, even if rainwater penetrates into the mortar layer 42 and reaches the inclined surface 4, the rainwater flows on the inclined surface 4 and is drained to the outside as shown by the arrows in FIG. 2. Thus, rainwater can be more reliably prevented from entering the room.

  (3) Since the slope of the slope 4 is approximately 1/50, it is possible to drain the rainwater on the slope 4 down the slope 4 reliably.

Second Embodiment
FIG. 5 is an enlarged cross-sectional view of a joint structure 1A of a precast concrete member according to a second embodiment of the present invention.
In the present embodiment, the configuration of the mortar layer 42A is different from that of the first embodiment, and the other points are the same as those of the first embodiment.
That is, the mortar layer 42A includes a first mortar layer 50 made of mortar and a second mortar layer 51 made of mortar provided on the outdoor side of the first mortar layer 50. Further, on the inside of the first mortar layer 50, a sealing material 52 is placed.

  When the mortar layer 42A is formed, after the first mortar layer 50 is formed, the second mortar layer 51 is formed on the outdoor side of the first mortar layer 50. By constructing in this manner, the boundary surface 53 is formed between the first mortar layer 50 and the second mortar layer 51.

According to the present embodiment, in addition to the above (1) to (3), the following effects can be obtained.
(4) Since the second mortar layer 51 is provided on the outdoor side of the first mortar layer 50, rainwater penetrates the second mortar layer 51, and the interface 53 between the first mortar layer 50 and the second mortar layer 51. However, as indicated by the arrows in FIG. 5, this rainwater moves downward along this boundary surface 53 to reach the inclined surface 4, and flows through the inclined surface 4 and is drained to the outside. Therefore, rainwater can be more reliably prevented from entering the room.

Third Embodiment
FIG. 6 is an enlarged cross-sectional view of a joint structure 1B of a precast concrete member according to a third embodiment of the present invention.
The present embodiment is different from the first embodiment in that the sealing material 60 is cast on the outdoor side of the mortar layer 42, and the other points are the same as the first embodiment.

That is, between the outer end 3 of the second floor 2 and the lower surface of the first floor member 10, the mortar layer 42, the backup material 61 provided on the outdoor side of the mortar layer 42, and the backup material 61 are provided. And a sealing material 60 disposed on the outdoor side.
A groove 62 extending along the outer periphery is formed immediately below the backup material 61 in the inclined surface 4.

According to the present embodiment, in addition to the above (1) to (3), the following effects can be obtained.
(5) The backup material 61 was provided on the outdoor side of the mortar layer 42, and the sealing material 60 was cast on the outdoor side of the backup material 61. Further, immediately below the backup material 61, a groove 62 extending along the outer circumference was formed. Therefore, when rainwater penetrates the sealing material 60 and reaches the backup material 61, the rainwater moves downward to reach the groove 62 of the inclined surface 4 as shown by the arrow in FIG. It flows and is drained outdoors. Therefore, rainwater can be more reliably prevented from entering the room.

First Reference Example
FIG. 7 is an enlarged sectional view of a joint structure 1C of a precast concrete member according to a fourth embodiment of the present invention.
In this reference example, the inclined surface 4 in the second outer end portion 3 of the floor surface 2 without, unlike that step 5 is formed with the first embodiment, the other points, similar to the first embodiment configured It is.
That is, the step 5 has a step upper surface 70 flush with the floor member 20, a step lower surface 71 provided on the outdoor side of the step upper surface 70 and lower than the step upper surface 70, and the step upper surface 70 and the step lower surface 71. And a step wall surface 72 which is a wall surface between them.

A silicate 41 is applied to the step 5 of the second floor 2 and the lower surface of the second floor member 30.
Further, between the step 5 of the second floor 2 and the lower surface of the second floor member 30, a mortar layer 42 made of mortar is formed.

According to this embodiment , the following effects can be obtained.
(6) The silicate 41 was applied to the outer end 3 of the second floor 2 and the lower surface of the first floor member 10. By reacting with water to gelate, the silicate blocks water (cracks) and voids, which are paths of the water, and exhibits waterproof performance. Therefore, when the moisture in the mortar layer 42 or the rainwater that has penetrated into the mortar layer 42 touches the silicate 41, the passage of water is blocked by the silicate 41, and therefore rainwater can enter the room at low cost. Can prevent it.

  Further, the step 5 including the step upper surface 70 and the step lower surface 71 was formed at the outer end 3 of the second floor surface 2 to which the second floor wall member 30 made of precast concrete is joined. Therefore, even if rainwater penetrates into the mortar layer 42 and reaches the lower surface 71 of the step, this rainwater does not reach the upper surface 70 of the step as shown by the arrow in FIG. Thus, rainwater can be prevented from entering the room.

Second Reference Example
FIG. 8 is an enlarged cross-sectional view of a joint structure 1D of a precast concrete member according to a second embodiment of the present invention. Specifically, FIG. 8 shows a joint between floor members 80.
The floor member 80 is a member made of precast concrete which is to be a rooftop floor, and the side surfaces of the floor member 80 are joined. A silicate 81 is applied to the side surface of the floor member 80, and a mortar layer 82 is formed between the side surfaces of the floor member 80.

According to this embodiment , the following effects can be obtained.
(7) The silicate 81 was applied to the side surface of the floor member 80. By reacting with water to gelate, the silicate blocks water (cracks) and voids, which are paths of the water, and exhibits waterproof performance. Therefore, when the moisture in the mortar layer 82 or the rainwater that has penetrated into the mortar layer 82 touches the silicate 81, the passage of water is blocked by the silicate 81, so it is possible for the rainwater to enter the room at low cost. Can prevent it.

  The present invention is not limited to the above-described embodiment, and modifications, improvements, and the like as long as the object of the present invention can be achieved are included in the present invention.

For example, in the first to third embodiments and the first reference example described above, the silicate 41 is applied to the outer end 3 of the second floor 2 and the lower surface of the second floor member 30, but the present invention is limited thereto. Alternatively, in addition to applying the silicate in this manner, the mortar layers 42, 42A may be mixed with silicate, and instead of applying the silicate, the mortar layers 42, 42A may be silicated. Salt may be mixed.
When silicate is mixed in the mortar layer 42A, silicate may be mixed in the entire mortar layer 42A, or silicate is mixed only in the first mortar layer 50 constituting the mortar layer 42A. Alternatively, silicate may be mixed only in the second mortar layer 51 constituting the mortar layer 42A.

Similarly, in the second reference example , the silicate 81 is applied to the side surface of the floor member 80, but the present invention is not limited thereto. Salt may be mixed, and instead of applying silicate, the mortar layer 82 may be mixed with silicate.

For example, in the first to third embodiments and the first reference example described above, in the case of mixing silicate into mortar layers 42 and 42A in addition to coating of silicate, a joint structure of precast concrete members The procedure for constructing 1 is as shown in the flowchart of FIG.
Steps S11, S12, and S14 are the same as steps S1, S2, and S4 of the first embodiment. Further, in step S13, the mortar 43 mixed with silicate is put on the outer end 3 of the second floor 2.

In the first to third embodiments and the first reference example described above, when silicate is mixed in the mortar layers 42 and 42A instead of applying silicate, the joint structure 1 of the precast concrete member is The procedure for construction is as shown in the flowchart of FIG.
Steps S21 and S13 are the same as steps S1 and S4 of the first embodiment. Further, in step S22, a mortar 43 mixed with a silicate is provided on the outer end 3 of the second floor 2.

Hereinafter, examples of the present invention will be described.
FIG. 11 is a schematic view showing the configuration of the experimental apparatus. A wall plate which is a precast concrete member is disposed on a floor plate which is a precast concrete member, and a mortar layer is provided between the floor plate and the wall plate. In this state, place the liner on one end of the floor slab, incline the floor slab and the wall slab so that the slope is 1/20, and water the surface on the lower side (that is, the outdoor side) of the mortar layer Dipped in

FIG. 12 shows experimental conditions and experimental results.
Example 1 applies the preventive agent to the floor plate and the joint surface between the wall plate and the mortar layer, and Example 2 adds the waterproof agent to the mortar layer in addition to the constitution of Example 1. It is a thing.

Here, the inhibitor applied to the bonding surface was Radcon 7 (manufactured by Environment Mien Co., Ltd.), and the application amount was 0.3 kg / m ² .
The waterproofing agent mixed in the mortar was Pacific NN (manufactured by Pacific Materials Co., Ltd.), and the amount used was 2% of the cement amount.

  As a result, as shown in FIG. 12, in the comparative example, the mortar layer was in a wet state, and water immersion occurred on the surface of the mortar layer on the indoor side. On the other hand, in Examples 1 and 2, the dried state of the mortar layer can be maintained, and no change occurs in the surface on the indoor side of the mortar layer. Therefore, it turned out that Example 1, 2 can exhibit waterproof performance.

DESCRIPTION OF SYMBOLS 1, 1A, 1B, 1C, 1D ... Bonding structure of a precast-concrete member 2 ... 2nd floor floor 3 ... outer end 4 ... inclined surface 5 ... level difference 10 ... 1st floor wall member 10A ... inclined surface 11 ... notch 12 ... bottom surface 13 ... wall surface 20 ... second floor floor member 20A ... inclined surface 30 ... second floor wall member 40 ... mortar 41 ... silicate 42, 42A ... mortar layer 43 ... mortar 50 ... first mortar layer 51 ... second mortar layer 52: seal material 53: boundary surface 60: seal material 61: backup material 62: groove 70: step upper surface 71: step lower surface 72: step wall surface 80: floor member 81: silicate 82: mortar layer

Claims (6)

A joint structure of precast concrete members in which a precast concrete wall member is joined to an outer end of a concrete floor surface,
At the outer end of the floor surface, an inclined surface is formed which descends toward the outdoor side,
A mortar layer is formed between the inclined surface of the floor surface and the lower surface of the wall member,
The mortar layer is provided only on the inclined surface,
A bonded structure of a precast concrete member, wherein a silicate is applied to the inclined surface of the floor surface and the lower surface of the wall member, and / or a silicate is mixed in the mortar layer. The joint structure of a precast concrete member according to claim 1 , wherein the slope of the inclined surface is approximately 1/50 or more. The joint structure for a precast concrete member according to claim 1 or 2 , wherein the mortar layer comprises a first mortar layer and a second mortar layer provided on the outdoor side of the first mortar layer. . Between the inclined surface of the floor and the lower surface of the wall member, in addition to the mortar layer, a backup material provided on the outdoor side of the mortar layer and an outdoor side of the backup material are provided. A sealing material is provided,
The joint structure of the precast concrete member according to claim 1 or 2 , wherein a groove extending along the outer periphery is formed immediately below the backup material in the inclined surface of the floor surface. A method of joining a precast concrete member in which a precast concrete wall member is joined to an outer end of a concrete floor surface,
At the outer end of the floor surface, an inclined surface is formed which descends toward the outdoor side,
Applying a silicate to the inclined surface of the floor surface and the lower surface of the wall member;
Depositing mortar only on the inclined surface of the floor surface;
Placing the wall member on the mortar , and bonding the precast concrete member. A method of joining a precast concrete member in which a precast concrete wall member is joined to an outer end of a concrete floor surface,
At the outer end of the floor surface, an inclined surface is formed which descends toward the outdoor side,
Applying a mortar mixed with silicate only on the slope of the floor surface;
Placing the wall member on the mortar , and bonding the precast concrete member.

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