Massive day today! 💪🏻7m excavation for a tunnel boring machine to bore a new sewer line. As mentioned in the previous post, I striped the topsoil and -600mm drop cut with the CAT 349 to prepare the area for this Komatsu PC350 which I would then operate. 3 different sized trench shoring boxes used staggered in size, with steel road plates on the ends to prevent cave ins. Hit a layer of hard mudstone below the 1st box, had a ripper attachment on hand to tear it out.
Full reach on this PC350 to reach the bottom, and of course couldn’t see much so had to rely on feel, and spotters to tell me where to position my bucket. Had to trim the excavation square tight to fit the next shoring boxes in.
We over dug by 200mm to allow for 100mm layer of blue metal (20mm clean rock) and then 100mm concrete work floor. The ground water came through at the end of the day and covered the 20mm clean rock as shown in the last pic.
My work is done here, we handed this small project over to the de-watering crew who will set up pumps tomorrow, for the tunnel boring to start Monday. Im off to start a new site on monday. Happy to finish Friday on a high with this dig going to plan👌🏻😎 #civilconstruction #earthmoving #tunnelboring #komatsu #pc350 #heavyequipment #diggingdeep #trenchbox #excavator #fullreach #sewerline #dailyconstruction #earthmovingdaily