Structural improvement in quality standards for shotcrete for primary lining in tunnel by Destructive & Non- destructive test methods

Mahesh Uttamrao Dange, "Structural improvement in quality standards for shotcrete for primary lining in tunnel by Destructive & Non- destructive test methods", IRT Proceeding on national conference on Innovative Approaches in Civil Engineering, 7-8 April, 2012, published by Indian research transaction, India

In this paper, presentation is given of introduction of shotcrete history in tunneling as well as destructive and non-destructive test methods for evaluating the shotcrete strength and quality of a tunnel primary lining. The relation between shotcrete properties (compressive strength, flexural strength modulus of elasticity, and homogeneity) measured across the tunnel profile and along the whole tunnel by applying the destructive and non-destructive methods. In destructive test methods are involving testing of compressive strength, flexural strength as per relevant standards. The non-destructive methods included an ultrasonic pulse velocity method and a hammer test.

 The main purpose of this is the development of a method that evaluates the quality of shotcrete in underground structures during and after the construction work. Through the application of non-destructive and destructive test methods it is possible to assess the state of a tunnel in order to improve construction work. This will result in the higher quality of the tunnel lining and durability of the tunnel as a whole and cut remediation and maintenance costs.

Shotcrete, Steel fibers, compressive strength, flexural strength homogeneity, modulus of elasticity, non-destructive and destructive test methods.

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