Fiber composite material refers to a composite material with fiber reinforcement effect formed by using high-strength continuous fibers arranged in a certain rule, impregnated with adhesive, bonded and solidified. The fiber-bonded composite reinforcement method is mainly suitable for the reinforcement of reinforced concrete under bending, axial compression, large eccentric compression and tension members. This method is not suitable for plain concrete members, including reinforcement of members with longitudinally stressed steel bars with a reinforcement ratio of less than 0.2% on one side. The following regulations should be strictly observed during the design and construction process:

(1) For reinforced concrete structural members, the on-site measured concrete strength grade shall not be lower than C15, and the positive tensile bonding strength of the concrete surface shall not be lower than 1.5MPa.

(2) When reinforced concrete structural members are reinforced with fiber composite materials, the fiber force mode should be designed to only bear tensile stress, and measures should be taken to remove or most of the live loads acting on the structure during construction.

(3) The fiber composite material pasted on the surface of the concrete member shall not be directly exposed to sunlight or harmful media, and its surface shall be protected. Surface protection materials should be harmless to fibers and adhesives, and should have reliable bonding strength and coordinated deformation properties with the adhesive. When the surface of the reinforced component has fire protection requirements, the fiber composite material should be protected in accordance with the fire resistance grade and fire limit requirements specified in the current national standard "Code for Fire Protection of Building Design" GB 50016.

4) For the concrete structure reinforced by this method, the long-term use environment temperature should not be higher than 60℃. When concrete structures in special environments (such as high temperature, high humidity, medium erosion, radiation, etc.) are reinforced by this method, in addition to corresponding protective measures in accordance with the current relevant national standards, adhesives resistant to environmental factors should be used , and paste it according to the special process requirements.

(5) When the positive bending moment area of the reinforced concrete flexural member is reinforced by the normal section, the fiber composite material pasted along the axial direction of the tension surface shall extend to the edge of the support. In addition, U-shaped hoops (for beams) or transverse beading (for boards) of fiber composite materials should be set at the ends (including the cutoff points) of the fiber composite materials and on both sides of the concentrated load point.

(6) When the fiber composite material is extended to the edge of the support and still does not meet the requirements of the extension length, the beam should be anchored with no less than three U-shaped hoops evenly within the extension length. One of them should be set at the end of the extended length. The U-shaped hoop is made of fiber composite material; the sticking height of the U-shaped hoop should be the cross-sectional height of the beam; when the beam has flanges or cast-in-place floor slabs, it should extend to its bottom surface. The width of the U-shaped hoop should not be less than 2/3 of the width of the reinforced fiber composite material for the end hoop, and should not be less than 150mm. The middle hoop should not be less than 1/2 of the width of the reinforced fiber composite strip, and should not be less than 100mm. The thickness of the U-shaped hoop shall not be less than 1/2 of the thickness of the reinforced fiber composite material under bending. For the board, a bead perpendicular to the direction of the stressed fiber shall be arranged in the extended length range. The layering is made of fiber composite material. In addition to arranging one layer at the end of the extension length, it is advisable to arrange 1-2 layers evenly within the extension length. The width of the bead shall not be less than 3/5 of the width of the reinforced fiber composite strip under bending, and the thickness of the bead shall not be less than 1/2 of the thickness of the reinforced fiber composite under bending.

(7) When the fiber composite material extends to the edge of the support, in the following situations, the end hoop (or end bead) should be replaced by a mechanical anchoring measure made of steel and reliable force transmission: the extendable length is less than half of the calculated length. The fiber composite material for reinforcement is a preformed sheet.

(8) When fiber composite materials are used to reinforce the positive section bearing capacity of the negative bending moment area of the flexural member, the fiber composite materials should be continuously pasted within the range of the negative bending moment envelope when there is no obstacle at the support. The cut-off point of its extension length should be located in the positive bending moment zone and should not be less than 1m away from the transition point of positive and negative bending moments. Although there are obstacles at the support, but there are cast-in-place slabs on the beam and the column is allowed to bypass, it is advisable to paste the fiber composite material on the slab surface within 4 times the thickness of the beam side.

(9) At the end nodes of the beams and columns on the top layer of the frame, when the fiber composite material can only be attached to the edge of the column and cannot be extended, structural glue should be used to attach L-shaped carbon fiber board or L-shaped steel plate to bond and anchor.

(10) When there is no cast-in-place slab on the beam, or the support of the negative bending moment area needs to be reinforced anchoring measures, the construction method of glued L-shaped steel plate can be adopted. However, the grade, diameter and quantity of anchor bolts of the hoop plate in the column shall be determined by calculation. When there are cast-in-place slabs on the beam, this structure can also be used for anchoring. Where the U-shaped steel hoop plate passes through the floor slab, the half-stack drilling method should be used. A flat hole is drilled in the plate to insert the hoop plate, and then the structural glue is used to seal it.

(11) When the reinforced flexural members are plates, shells, walls and cylinders, the fiber composite materials should be pasted in a dense manner, and the width of each strip should not be greater than 200mm. It is not allowed to use the whole fabric which has not been cut into strips. When the multi-layer fiber fabric pasted by the bending member is allowed to be cut off, the two adjacent layers of fiber fabric should be cut off in layers according to the principle of inner short and outer length. The cut-off point of the outer fiber fabric should exceed the cut-off point of the inner layer by more than 200mm, and a U-shaped hoop should be added at the cut-off point.

(12) When fiber composite materials are used to reinforce the oblique section bearing capacity of reinforced concrete beams or columns, the structure should meet the following requirements:

1 It is advisable to use a ring hoop or a self-locking U-shaped hoop at the end; when hoop is only required for the structure, a general U-shaped hoop can also be used;

2 The fiber force direction of the U-shaped hoop should be perpendicular to the axial direction of the component;

3 When the ring hoop, end self-locking U-shaped hoop or general U-shaped hoop uses fiber composite strips, the net spacing should not be greater than 0.70 times the maximum stirrup spacing of the national standard, and no greater than 0.5 times the beam height ；

4 The sticking height of the U-shaped hoop should meet the specifications; when the upper end of the U-shaped hoop has no self-locking device, it should be anchored by sticking a longitudinal bead;

5 When the height h of the beam is greater than or equal to 600mm, a longitudinal waist pressure belt should be added to the waist of the beam; if necessary, a self-locking device can also be added to the end of the waist pressure belt.

(13) When using the circumferential bundle of fiber composite material to strengthen the reinforced concrete column with normal cross-section or enhance the ductility of seismic reinforcement, its structure should meet the following requirements:

1 The number of fiber fabric layers of the hoop bundle shall not be less than 2 layers for circular cross-sections. There should be no less than 3 floors for square and rectangular cross-section columns. When there is reliable experience, the minimum number of layers for a rectangular section column reinforced with aramid fiber fabric can also be 2 layers.

2 The overlap width between the upper and lower layers of the hoop bundle shall not be less than 50mm, the extension length of the loop cut-off point of the fiber fabric shall not be less than 200mm, and the overlap position of each strap shall be staggered with each other.

(14) When the fiber composite material is pasted along the axis of the column to strengthen the front section bearing capacity of the large eccentric compression column, the fiber composite material should avoid the floor beams and cross the floor along the column corners, and the fiber composite material should be plate. The anchoring structure of the upper and lower ends shall be mechanically anchored. At the same time, try to avoid cutting the fiber composite material at the floor.

(15) When U-shaped hoop, L-shaped fiberboard or hoop bundles are used for reinforcement and need to be bypassed at the external corners of the component, the edges and corners of the section should be rounded by polishing before pasting. The rounding radius r of the beam should not be less than 20mm for carbon fiber and glass fiber; it should not be less than 15mm for aramid fiber; the rounding radius of the column should not be less than 25mm for carbon fiber and glass fiber; and it should not be less than 20mm for aramid fiber. .

(16) When fiber composite materials are used to reinforce large eccentrically compressed reinforced concrete columns, their structure should meet the following requirements:

1 Reliable mechanical anchoring measures should be added at both ends of the column;

2 When there is a floor slab at the upper end of the column, the fiber composite material shall pass through the floor slab and shall have sufficient extension length.