Using Sprayed Polymer as Tunnel Support

Komurlu, Eren (Karadeniz Technical University) | Kesimal, Ayhan (Karadeniz Technical University)



Mechanical characterizations of some polymer materials have been investigated as a tunnel support material. They were compared with conventional concretes. There are candidate polymers to be used as support material for tunnelling. Very thinner polymer wall can supply same support pressure instead of shotcrete. Lackings of concrete can be removed by using polymer materials. If polymer support’s stiffness is very few for some tunnelling zone, fiber glass or carbon fiber can be used as an addition for increasing stiffness and strength in the same time. Polymers are preferable and economical support materials especially for swelling clay zones. Poymers allow to deform while they are supplying same or near strength because of their ductile material characteristic. And, they have much more dynamic load strength than concrete’s. There is no need to membranes or other water resisting materials in sprayed-polymer application area. It can be easily sprayed with smaller air pressures by heating, or some of them are sprayed without heating, in liquid form. They reach their maximum strength quantites in very few time (like several minutes) after sprayed so polymer support materials allow to decrease advancing time. Polymer spraying application is practical and there is no rebound problem in sprayed-polymer application. Candidate polymer types were compared within.