Shotcrete:Structural Testing of Thin Liners.

摘要

This report presents the results of engineering studies related to the development of new and improved tunnel support systems. Thin shotcrete layers were studied to assess their capacity and behavior as temporary tunnel supports. The design,construction,and operation of a large-scale test facility simulating a planar tunnel roof with a punching block 2ft x 2ft (60.8cm x 60.8cm) are described. Preliminary tests were conducted using thin mortar layers to assess the performance of the test device and the principal variables controlling the capacity of the thin liner. Results obtained from these tests were used in the planning and evaluating of the shotcrete test program. This report describes the development of the test-device,the equipment,and its arrangement and the shotcrete used in the model. The capacity of shotcrete layers for different thickness and strength of shotcrete and shotcrete-rock bond was determined.