Explosion-resistant reinforcing structure for masonry outer wall of existing building

Abstract

The utility model discloses an anti-explosion reinforcing structure for a masonry outer wall of an existing building, which relates to the technical field of anti-explosion reinforcement of masonry walls and comprises a wall body, a frame beam column is arranged on the outer edge of the wall body, and the thickness of the frame beam column is larger than that of the wall body, so that a protruding part protruding out of the wall body is formed; a plurality of anchor bars are fixedly arranged in the protruding part at intervals, and the other ends of the anchor bars extend out of the protruding part; a reinforcing steel bar is fixedly connected between two anchor bars which are opposite left and right or up and down, and the crisscrossed reinforcing steel bars are lapped together to form a reinforcing mesh; the reinforcing mesh is coated with high-ductility concrete, so that a structural layer is formed between the reinforcing mesh and the wall body; according to the utility model, the reinforcing and bearing capacity of the single-side surface layer can be effectively improved, more application scenes of larger explosion incident overpressure load can be adapted, and the potential safety hazard of deformation, cracking, falling or splashing of the original mortar surface layer is prevented; and the method has the advantages of reliability, safety, low construction cost, simplicity in construction, short wet operation period and the like.

Description

TECHNICAL FIELD

[0001] The utility model relates to masonry wall blast-resistant reinforcement technical field, concretely relates to a blast-resistant reinforcement structure for existing building masonry external wall. BACKGROUND

[0002] For the existing building of petrochemical industry with explosion risk hidden danger, the masonry external wall changes from the structural enclosure wall to the main force barrier resisting explosion impact load, and the risk of external wall rupture and splashing under the action of explosion load is very high, therefore, the safety, professionalism, implementability and economy of the blast-resistant reinforcement method of masonry external wall are very important; based on LS-dyna, the structural response analysis of damage deformation of masonry external wall under explosion load working condition and masonry wall explosion test can evaluate the necessity and importance of blast-resistant reinforcement of masonry wall.

[0003] According to the 3.0.11 clause of the "petrochemical building blast-resistant design standard" (GB / T50779-2022), the blast-resistant wall structure form of different explosion incident overpressure range is described, and the allowable value of external wall support corner deformation is specified in table 6.1.3. According to the 8.3.8 clause, the reinforcement method of existing building masonry wall usually adopts blast-resistant coating reinforcement method, external coating reinforcement method, pasting composite material reinforcement method, buttress column reinforcement method, steel structure + blast-resistant plate shelter method and the like, and the existing reinforcement methods have the following problems:

[0004] 1. Blast-resistant coating reinforcement method: according to the requirements of appendix D of GB / T50779-2022, the existing external wall body conditions are required to be higher, and more than 50% of the existing buildings do not meet the coating spraying conditions through market research;

[0005] 2. External reinforced concrete wall reinforcement method: when the new external wall foundation is built, it is greatly affected by the obstacles such as buried cable, pipeline and the like around the building, especially the high migration and construction disturbance risk of cabinet cable, and this reinforcement method also has the disadvantages of long wet operation period and the like;

[0006] 3. Pasting composite material reinforcement method: this method has higher requirements for wall body and mortar base layer conditions, and the improvement of wall body plane external bearing capacity is limited, which is not suitable for the scene with large explosion incident overpressure load, and has great limitations;

[0007] 4. Buttress column reinforcement method: because the setting of column has great influence on indoor use area and wall surface decoration beauty, the construction unit seldom adopts it;

[0008] 5. Steel structure + blast-resistant plate shelter: this method is widely used in the market, but also has certain shortcomings, for example, the corrosion resistance life of blast-resistant plate steel plate and fixing bolt is affected by anticorrosion coating or coating, so that the service life of blast-resistant building is shorter than that of other reinforcement methods, and the anticorrosion maintenance requirement in the later period is higher;

[0009] 6. The outer layer reinforcement method: ① Double-sided reinforced mortar surface layer reinforcement method, the inner side and the outer side of the outer wall are reinforced, the wall body is tensioned, the construction operation is complex, the engineering cost is higher, and it is not applicable to the case that the outer wall is insufficient in the fireproof spacing with the device. ② Single-sided reinforced mortar surface layer reinforcement method: only the inner side of the outer wall is increased with a reinforced mortar surface layer, this method mainly relies on the reinforced mesh to constrain the masonry wall, when the load is large, the masonry wall (especially the low-strength block masonry) will be crushed in the compression zone, resulting in large deformation of the reinforced surface layer on one side, instantaneous cracking and falling of the structural layer, and the risk of flying debris. Practical new type content

[0010] The utility model aims at providing a kind of for existing building masonry outer wall blast-resistant reinforcement structure, can effectively improve the bearing capacity of single-sided surface layer reinforcement, can adapt to more larger explosion incident overpressure load application scene, prevent the security risk hidden danger of original mortar surface layer deformation cracking and falling or splashing;And with simple structure, reliable safety, low construction cost, simple construction, short wet operation period and other advantages.

[0011] The utility model includes wall body, the outer edge of wall body is provided with frame beam column, the thickness of frame beam column is greater than wall body, to form the protruding portion protruding to wall body outside;Several anchor bars are fixedly arranged in the protruding portion at intervals, and the other end of the anchor bar extends to the outside of the protruding portion;Steel bars are fixedly connected between the two anchor bars opposite to each other or above and below, and the steel bars are vertically and horizontally interlaced to form a reinforced mesh;High-ductility concrete is coated on the reinforced mesh, so that a structural layer is formed between the reinforced mesh and the wall body.

[0012] After the above structure is used, the reinforcement method of reinforced mesh and high-ductility concrete is used, the high-ductility concrete surface layer and the built-in reinforced mesh act together, effectively improve the tensile bearing capacity of the tensile zone of the wall body and the deformation constraint capacity of the wall body;With simple structure, reliable safety, low construction cost, simple construction, short wet operation period and other advantages;At the same time, the high-ductility, high-toughness, high-strength (tensile), high-anti-cracking performance and high-damage-resistance capacity of the fiber concrete and the built-in reinforced mesh can effectively constrain the deformation of the wall body, the blast-resistant bearing capacity is greatly improved compared with the reinforced mortar surface layer, and the safety risk hidden danger of the mortar surface layer cracking and flying due to excessive deformation of the wall body is solved.

[0013] Preferably, the anchor bar includes a straight anchor and an L-shaped anchor, the straight anchor is fixed into the protruding portion of the frame beam column, and the L-shaped anchor is fixed vertically into the frame beam column.

[0014] Preferably, the range of 600mm downward from the top of the wall body is a load-bearing portion, and the spacing between the adjacent two steel bars in the load-bearing portion is 100mm.

[0015] Preferably, the distance between two adjacent steel bars in the area below the load-bearing part is 200mm.

[0016] Preferably, the high-ductility concrete comprises cement, quartz sand and fiber reinforced material.

[0017] Preferably, the thickness of the surface layer formed by the high-ductility concrete is between 30mm and 40mm.

[0018] Preferably, the anchor steel bar and the steel bar on the steel mesh are fixed together by welding, so that a welding lap area is formed at the welding position, and two adjacent welding lap areas are arranged staggeredly.

[0019] In summary, the present utility model has the following advantages:

[0020] 1. The reinforcing method of steel mesh and high-ductility concrete is adopted, so that the high-ductility concrete surface layer and the built-in steel mesh act together, effectively improving the tensile bearing capacity of the tensile area of the wall body and the deformation capacity of the constrained wall body, fully exerting the high toughness, high strength (tensile), high flexural crack resistance and high damage resistance of the fiber concrete, and having the advantages of simpler structure, reliable safety, low construction cost, simple construction, short wet operation period, etc.

[0021] 2. The anchor steel bar comprises two structures of straight anchor and L-shaped anchor, when the size of the protruding part of the frame beam column is appropriate and suitable for installing the anchor steel bar, the straight anchor is directly inserted into the protruding part; when the size of the protruding part of the frame beam column is small, the installation space of the anchor steel bar is insufficient, the L-shaped anchor can be vertically inserted into the frame beam column, and the installation and selection are more flexible, and the anchor steel bar is suitable for various wall surfaces.

[0022] 3. The anchor steel bar and the steel bar on the steel mesh are fixed together by welding, compared with the fixing method of the fastener such as a bolt, the welded steel mesh has higher strength, is more convenient to install, has simpler structure and lower manufacturing cost. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 Figure 2 is a side sectional view of the present utility model for anti-explosion reinforcing structure of existing building masonry wall;

[0024] Figure 2 Figure 3 is a partial enlarged view of the middle frame beam column; Figure 1

[0025] Figure 3 Figure 5 is a schematic diagram of the anchor structure of the end of the steel mesh and the frame beam column;

[0026] Figure 4 Figure 6 is a plan layout diagram of the steel mesh lap.

[0027] ​In the figure: 1, wall; 2, frame beam column; 3, anchor bar; 301, straight anchor; 302, L-shaped anchor; 4, steel bar; 5, high ductility concrete; 6, bearing part; 7, welding lap zone; 8, roof; 9, ground beam; 10, indoor floor; 11, outdoor floor; 12, rigid floor; 13, mortar filling zone. DETAILED DESCRIPTION

[0028] The utility model will be further described below with reference to the drawings.

[0029] The directions referred to in the specification are based on the normal working position of the anti-explosion reinforcing structure for the existing building masonry outer wall of the utility model, and do not limit the position during storage and transportation, and only represent the relative position relationship, not the absolute position relationship.

[0030] As Figures 1 to 4 As shown in the drawings, an anti-explosion reinforcing structure for the existing building masonry outer wall comprises a wall 1, and the outer edge of the wall 1 is provided with a frame beam column 2. Generally, the thickness of the frame beam column 2 is greater than that of the wall 1, so that a protruding part protruding outward of the wall 1 is formed. A plurality of anchor bars 3 are fixedly arranged in the protruding part at intervals, and the other ends of the anchor bars 3 protrude outward of the protruding part. Steel bars 4 are fixedly connected between two anchor bars 3 opposite to each other in the left-right direction or in the up-down direction. The longitudinal and transverse steel bars 4 are cross-connected to form a steel bar mesh. The transverse and longitudinal steel bars 4 are connected together by twisting wires. Preferably, the diameter of the steel bar 4 is 8 mm in the embodiment.

[0031] Further, the anchor bar 3 comprises two structures of a straight anchor 301 and an L-shaped anchor 302. When the size of the protruding part of the frame beam column 2 is suitable for installing the anchor bar 3, the straight anchor 301 is directly inserted into the protruding part. When the size of the protruding part of the frame beam column 2 is small, the installation space of the anchor bar 3 is insufficient, and the L-shaped anchor 302 is vertically inserted into the frame beam column 2 for easy installation.

[0032] Further, the range of 600 mm downward from the top of the wall 1 is a bearing part 6. The distance between the adjacent two steel bars 4 in the bearing part 6 is 100 mm. The distance between the adjacent two steel bars 4 in the area below the bearing part 6 is 200 mm. The density of the steel bars 4 is increased in the bearing part 6, so that the strength of the bearing part 6 is higher.

[0033] The steel bar mesh is coated with high ductility concrete 5, so that a structural layer is formed between the steel bar mesh and the wall 1, and the steel bar mesh and the wall 1 are integrated. The wall 1 and the structural layer work together, so that the strength of the entire wall 1 and the reinforcing structure is higher. Preferably, the thickness of the surface layer formed by the high ductility concrete is between 30-40 mm in the embodiment, which occupies less space while ensuring sufficient strength.

[0034] High ductility concrete 5 is a fiber reinforced cementitious composite material based on the principle of micromechanics design, which has high ductility, high damage tolerance, high durability, high strength (compressive and tensile) and good crack control ability, so it is also called "bendable concrete"; high ductility concrete 5 includes cement, quartz sand and fiber reinforced material, common fiber reinforced materials include polypropylene coarse fiber and polyvinyl alcohol fiber, and the fiber binding effect is the key to its high ductility; therefore, the structure layer formed by high ductility concrete 5 can adapt to more large explosion incident overpressure load application scenarios, and reduce the safety hazards of deformation, cracking and spalling of the original mortar surface layer.

[0035] Further, the anchor bar 3 and the steel bar 4 on the steel mesh are fixed together by welding, so that a welding lap joint area 7 is formed at the welding position, and the two adjacent welding lap joint areas 7 are arranged staggered; compared with the fixing mode of fasteners such as bolts, the steel mesh fixed by welding has higher strength, faster installation, simpler structure and lower manufacturing cost; at the same time, the staggered welding lap joint areas 7 can effectively prevent the defects of the welding area from being concentrated in one place, so that the strength is more reliable.

[0036] It should be noted that the bottom of the steel mesh of the lowest floor needs to be filled with mortar and fixed below the ground; the length of the bottom of the steel mesh below the ground is not less than 500mm.

[0037] During construction, the following steps can be followed:

[0038] Step one: base surface treatment: remove the wall putty layer, and chisel the original mortar surface layer to ensure effective bonding of the base surface and the high ductility concrete surface layer;

[0039] Step two: anchoring: drill holes in the protruding part of the frame beam column and anchor the anchor bar in the frame beam column by chemical method (such as glue filling), and the steel bar can be arranged according to the length and position of the lap joint requirement, when the size of the protruding part of the frame beam column is too small, the steel bar can be bent and anchored (L type anchor), avoiding the influence of the longitudinal reinforcement of the beam column on the anchoring;

[0040] Step three: force steel bar fixed connection: the steel mesh and the anchoring section are connected by welding or mechanical connection, and the bottom of the steel bar should be embedded and anchored in the indoor rigid ground below not less than 500mm when there is no floor on the ground;

[0041] Step four: high ductility concrete surface layer finishing: the design thickness of the surface layer is generally 30-40mm, the thickness of each layer should not exceed 15mm, and the construction interval of each layer should not exceed 3-4 hours.

[0042] Of course, the above description is not a limitation of the utility model, the utility model is also not limited to the above examples, the changes, modifications, additions or replacements made by the person skilled in the art within the essential scope of the utility model should also belong to the protection scope of the utility model.

Claims

1. A blast-resistant reinforcement structure for an existing building masonry exterior wall, comprising a wall body (1), the outer edge of the wall body (1) is provided with a frame beam column (2), the thickness of the frame beam column (2) is greater than the wall body (1), thereby forming a protruding part protruding outwardly from the wall body (1); characterized in that: A plurality of anchor bars (3) are fixedly arranged in the protruding part, and the other ends of the anchor bars (3) extend out of the protruding part; a steel bar (4) is fixedly connected between two anchor bars (3) opposite to each other in the left-right direction or in the up-down direction, and the longitudinal and transverse intersecting steel bars (4) are overlapped to form a steel bar mesh; high ductility concrete (5) is coated on the steel bar mesh, so as to form a structural layer between the steel bar mesh and the wall body (1).

2. The anti-explosion reinforcing structure for the masonry outer wall of an existing building of claim 1, wherein: The anchor bars (3) include straight anchors (301) fixedly arranged in the protruding part of the frame beam column (2) and L-shaped anchors (302) fixedly arranged in the frame beam column (2) perpendicularly.

3. The anti-explosion reinforcing structure for the masonry outer wall of an existing building according to claim 1, characterized in that: A load-bearing part (6) is arranged in a range of 600 mm from the top of the wall body (1) downwards, and the interval between two adjacent steel bars (4) in the load-bearing part (6) is 100 mm.

4. The anti-explosion reinforcing structure for the masonry outer wall of an existing building of claim 3, wherein: The interval between two adjacent steel bars (4) in a region below the load-bearing part (6) is 200 mm.

5. The anti-explosion reinforcing structure for the masonry outer wall of an existing building according to claim 1, characterized in that: The high ductility concrete (5) includes cement, quartz sand and fiber reinforced material.

6. The anti-explosion reinforcing structure for the masonry outer wall of an existing building according to claim 1, characterized in that: The thickness of a surface layer formed by the high ductility concrete (5) is between 30 mm and 40 mm.

7. The anti-explosion reinforcing structure for the masonry outer wall of an existing building according to claim 1, characterized in that: The anchor bars (3) and the steel bars (4) on the steel bar mesh are fixedly connected by welding, so as to form a welded overlapping area (7) at the welding position, and two adjacent welded overlapping areas (7) are arranged staggeredly.

Images