In the field of building reinforcement engineering, rebar adhesive and steel bonding adhesive are two common types of structural adhesives, both playing significant roles in the construction of structural elements. However, there is a frequent inquiry from those involved in reinforcement as to whether rebar adhesive and steel bonding adhesive can be interchangeably used on the construction site. The answer is definitely no.
Here is a detailed analysis for everyone:
From the relevant regulations, it is understood that in the "Code for Acceptance of Construction Quality of Building Structure Reinforcement Engineering" GB50550-2010, it is stipulated that during reinforcement, the use of "rebar-steel bonding dual-purpose adhesive" is strictly prohibited.
From this, it can be seen that rebar adhesive cannot replace steel bonding adhesive. The adhesive selected for rebar reinforcement is rebar structural adhesive, while the adhesive selected for steel bonding reinforcement is steel structural adhesive.
Differentiate between rebar adhesive and steel bonding adhesive based on their characteristics and uses.
Rebar adhesive is mainly used to embed steel bars or screws into concrete structures to increase the connection and load-bearing capacity of the structure. It requires good anchoring performance, capable of forming a solid bond in the concrete, and able to withstand tensile and shear forces.
Steel bonding adhesive, on the other hand, is used to bond steel plates to the surface of concrete structures, enhancing the strength and rigidity of the structure through the coordinated work of the steel plate and concrete. Steel bonding adhesive needs to have higher bonding strength and shear strength to ensure effective bonding between the steel plate and concrete.
Although both rebar adhesive and steel bonding adhesive belong to the category of adhesives, they have distinct differences in performance requirements and application scenarios. In terms of performance, rebar adhesive focuses more on anchoring performance and long-term stability, as the embedded steel bars need to maintain a solid connection in the concrete and withstand various complex loads. Steel bonding adhesive, however, requires better flexibility and impact resistance to adapt to deformation during the structural load process.
From the perspective of concrete bonding strength, when using rebar adhesive for rebar embedding, the anchoring position must not have any local defects. When the newly added component is a cantilever structural member, the original concrete strength grade shall not be lower than C25; when the newly added component is another structural component, the original concrete strength shall not be lower than C20.
Steel bonding reinforcement is achieved by pasting steel plates and is suitable for the reinforcement of concrete bending, large eccentric compression, and tensile members. The existing concrete structure members to be reinforced should have a measured concrete strength of not less than C15, and the concrete surface's direct tensile bond strength should not be less than 1.5MPa. Moreover, the direction of force is designed to withstand axial stress.
Strictly follow the relevant specifications
Due to these differences, rebar adhesive and steel bonding adhesive cannot be used interchangeably. If rebar adhesive is mistakenly used for steel bonding reinforcement, it may lead to unstable bonding between the steel plate and concrete due to performance mismatch, failing to achieve the expected reinforcement effect. Similarly, if steel bonding adhesive is used for rebar embedding, it may not provide sufficient anchoring force, affecting the safety of the structure.
When carrying out structural reinforcement, the appropriate adhesive should be selected according to specific reinforcement needs and design requirements, and construction should be carried out strictly in accordance with relevant specifications and standards to ensure the quality and safety of the reinforcement project.
