High-strength bolts. Installation of high-strength bolts shall be inspected in accordance with section 1704.3.3 of Chapter 17 of NYC Building Code and AISC 360.
Exception: Installation of high strength bolts in bearing type connections where the calculated connection strength is at least twice the required strength of the connection. Inspection of such connections shall be made under Section 1704.3.2. Such connections shall be clearly indicated on the approved construction documents.
TR1 INSPECTION ITEM: High strength bolting inspection is a required TR1 inspection item and is performed by a certified Bolting inspector. The certified bolting inspector must be certified by the International Code Council and should have a minimum of three years of work experience performing structural steel bolting inspections.
While the work is in progress, the special inspector shall determine that the requirements for bolts, nuts, washers, and paint; bolted parts and installation and tightening in such standards are met. For bolts requiring pre-tensioning, the special inspector shall observe the pre-installation testing and calibration procedures when such procedures are required by the installation method or by project plans or specifications; determine that all plies of connected materials have been drawn together and properly snugged and monitor the installation of bolts to verify that the selected procedure for installation is properly used to tighten bolts. For joints required to be tightened only to the snug-tight condition, the special inspector need only verify that the connected materials have been drawn together and properly snugged.
Periodic inspection. Inspection of bolt installation for pre-tensioning is permitted to be performed on a periodic basis when using the turn-of-nut method with match marking techniques, the direct tension indicator method, or the alternate design fastener (twist-off bolt) method. Joints designated as snug tight need to be inspected only on a periodic basis.
1704.3.3.3 Continuous inspection. Inspection of bolt installation for pre-tensioning using the calibrated wrench method or the turn-of-nut method without match marking shall be performed on a continuous basis.