High temperature welding is possible after planting reinforcement

Can high temperature welding be performed after tendon implantation? Do you consider its high temperature resistance when choosing planting adhesive? The common point between these two questions is whether the planting adhesive can handle high-temperature welding? The existence of these problems also reflects a common phenomenon: there is a need for post welding in some reinforcement projects in practical applications.

So, why do people have these concerns? The reason is that the temperature of reinforcement welding can reach over a thousand degrees Celsius, and the thermal decomposition temperature of epoxy reinforcement adhesive is generally between 180 ° C-300 ° C. If no protective measures are taken and welding is carried out directly, the high temperature generated by welding will cause the adhesive to lose its bonding performance, resulting in strength failure and detachment of the reinforcement.

So this approach is not advisable, so how to prevent and improve the impact caused by high-temperature welding has become our primary consideration. The core measure cannot be separated from high temperature prevention, which is to reasonably control the temperature of the colloidal part.

In Article 19.1.5 of GB50550-2010 "Code for Acceptance of Construction Quality of Building Structure Reinforcement Engineering", clear provisions have been made for the treatment of welding after planting reinforcement: when planting reinforcement, the reinforcement should be welded first and then planted. When it is difficult to weld later, the welding point should be more than 15 days away from the surface of the substrate concrete, and the root of the exposed part of the planting reinforcement should be wrapped in ice water soaked wet towels in multiple layers. The principle of welding first and then planting reinforcement is still adhered to for batch planting of reinforcement, to ensure that the adhesive layer is not damaged due to high temperature.

From the above relevant specifications, it can be seen that by taking corresponding protective measures, the temperature near the colloid can be maintained within a relatively safe range, which will not affect the colloidal properties of the planting glue or can significantly reduce the impact on the colloidal properties. When high-temperature welding is required for reinforcement by planting reinforcement, welding with appropriate protective measures is feasible. Meanwhile, the following methods can also be adopted.

Firstly, increase the anchoring depth appropriately. Experiments have shown that increasing the anchoring depth appropriately can not only improve the ultimate tensile bearing capacity of the planted reinforcement, but also reduce the sliding amount of the planted reinforcement. Secondly, increase the distance between the solder joint and the planting adhesive layer. Increasing the distance between the solder joint and the adhesive layer directly reduces the impact of high-temperature welding on the reinforcement. Then, other connection methods can also be used, such as binding and overlapping, mechanical connection. This method can make construction simpler, and its quality is also relatively stable without damaging the steel bars. However, the specific connection method to be used needs to be arranged according to the actual situation, and a reasonable choice should be made based on standard specifications.

In addition, when the above methods are not suitable, choosing a high temperature resistant planting adhesive can avoid problems from the source.

Poor quality planting adhesive is often not resistant to high temperatures. As the temperature increases, the impact on the colloidal properties becomes greater, and the bonding ability decreases faster, resulting in the loss of bearing capacity.

In order to ensure the reinforcement effect, we should choose planting adhesive with high temperature resistance, strong bonding ability, and high tensile strength for reinforcement.

So, a high-quality planting adhesive can not only play a high-strength bonding role in planting reinforcement engineering, but also reduce the impact on high-temperature welding, and its reinforcement significance is significant. In summary, the planting adhesive with a high-temperature welding resistance report is a dual guarantee for the reinforcement of planting reinforcement.