Sizewell B Power Station

摘要

I have been interested in the declutching of the sheet piles reported on the beach works (paper 10098, paragraphs 36 and 39). Could the authors elaborate on the reasons for the failure of the sheet piles and, in particular, a proposition that the clutches were opened by particular-sized pebbles in the Norwich Crags? In paragraph 36 the authors state that N values were in the range 60-120 over the last 10 m of driving. My own inspection of lvalues over this range gives much higher individual values of up to 174. From information in the British Steel Corporation's Piling handbook it seems that the choice of a 122 kg/m section 6 pile rather than the heaviest available (138 kg/m) could lead to damage to the piles when they are driven in ground with high N values indicated. Would the authors agree that the selection of piles was possibly at fault and that the damage to the piles was possibly caused by hard driving in hard ground?