TUNNELLING HAS damaged a number of houses above the Dublin Port Tunnel route.
Residents say up to nine houses have been damaged, two with significant cracks, after a tunnel boring machine passed 20-25m below houses in the suburb of Marino.
Client Dublin City Council issued instructions on Tuesday to joint venture contractor Nishimatsu-Mowlem-Irishenco (NMI) to slow down tunnelling and reduce working hours to minimise disturbance and the risk of damage.
The contractor was ordered to reduce tunnelling rates from 4045mm/min by 25%, and restrict tunnelling hours from 7am to 8pm rather than 11pm.
Deputy Dublin City Engineer Tim Brick told NCE that the contract allowed for hours to be cut back where there was disturbance to residents.
The Marino Development Action Group, which opposes the tunnel work, said it had postponed a High Court action to suspend the work after the council offered to bring Imperial College engineering geologist Dr Michael de Freitas back to site to examine the work.
De Freitas was previously engaged to reassure residents of over 300 homes along the route about potential damage from site investigations.
The damaged houses date from the 1940s. Tunnelling is in Dublin Limestone overlain by stiff boulder clay.
Meanwhile, Irish Rail has rejected a report by NMI consultant Charles Haswell into subsidence before Christmas under a nearby railway line.
Futher investigations are continuing.