HSFG bolts have the following advantages when compared with normal bolts :
(i) The performance of preloaded HSFG bolts under fatigue loading is good because the prestressed bolts are subjected to reduced stress range during each loading cycle when compared with unloaded bolts.
(ii) For structures adjacent to machinery which generate substantial vibration, preloading bolts can help to avoid the loosening of bolts.
(iii) HSFG bolts are used in connections where any slight slip movement would render the integrity of the whole structures break down.
(iv) Owing to its high tensile strength, it is commonly used in connections which require the taking up of high flexure and the tensile stress generated could be readily resisted by it high tensile strength.
This question is taken from book named – A Self Learning Manual – Mastering Different Fields of Civil Engineering Works (VC-Q-A-Method) by Vincent T. H. CHU.
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