Which risk increases when welding rebar cages without preheating in cold weather concrete pours?

💡 Explanation

When welding rebar in cold weather without preheating, rapid cooling causes hydrogen embrittlement because moisture in the air decomposes during welding, leading to hydrogen diffusing into the weld metal causing cracking. Therefore, hydrogen-induced cracking risks increase, rather than corrosion, reduced concrete strength, or chloride penetration require different conditions.

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