USE OF COOPER SLAG FOR SURFACE TREATMENT OF SLIP-CRITICAL HIGH-STRENGTH BOLTS

Introduction. The article discusses the results of testing slip-critical high-strength bolts whose contact surfaces are treated using copper slag having a fraction 0.5–2.5 mm (this processing method was used directly on construction site for installation roof steel structures covering concert hall). An additional assessment bearing capacity samples carried out factoring in local damage to friction detected around bolt holes during installation. Aim. In this work, actual coefficient μ joints determined when order confirm design = 0.42. Materials and methods. manufacturing were following company standard 006-97 «High-strength bridges». Each sample comprised stack three C355 plates thickness 16, 25, 16 (GOST 27772-2015), tightened M27 (10.9) 52644). control tests groups where differently out: № 1 – factory, 2 treatment mm, 3 with an artificial defect created hole. Results. On basis obtained test results, it concluded whether further surface can be employed site. Conclusions. offered at or above that value (0.42) (in these specific conditions, even including identified defects modeled testing). Although such remains unregulated by regulatory documents, is gaining great popularity. Therefore, necessary carry research use (including various fractions) substantiate introduction documents.