British Land has said a number of bolts on Rogers Stirk Harbour and Partners’ Leadenhall building are to be replaced, after it was revealed a third bolt had fractured on the skyscraper
The bolt was captured by precautionary tethering put in place when two of the steel bolts on the fifteenth floor of the RSHP-designed Cheesegrater tower broke back in November (AJ 05.11.14).
Investigations by contractor Laing O’Rourke and structural engineers Arup have confirmed the problem is limited to certain bolts and that there is ‘no adverse effect on the structural integrity of the building’.
Recently completed testing concluded that the bolts, described as the size of a human arm, fractured due to a material failure called hydrogen embrittlement.
As a precautionary measure a programme to replace a number of bolts on the Leadenhall Building is set to take place.