What are the reasons for the two lining concrete lining of the tunnel?
(4) improper concrete mix, segregation, depending on the template part of the lack of slurry or template serious leakage;(5) no watering wood template wet, water bonding or early form removal, Chaimo missing edge off angle, resulting in reinforcement.
(3) the concrete pump tube, vibration rod and other mechanical repeated impact, workers trample or vibrator touch bar, caused by displacement and deformation of steel exposed.
(1) the steel frame is put aside, there is no reinforcement pad or pad number is not enough, the position is not correct, resulting in the reinforcement close to the template and exposed.(2) the coarse aggregate size is greater than the reinforcement spacing, or the debris is placed in the steel frame, while the concrete leakage, forming a serious honeycomb and holes and exposing the reinforcement.
