Physical and numerical experimental study of stress-strain state of the structure lining of a shallow tunnel

摘要

This article refers to research carried out to determine the stress-strain state of the structurernlining of a shallow tunnel subjected to an increase of the forces acting on the ground surface, using two differentrnmethods and independent, allowing it to compare the results obtained from the magnitude of the maximumrnstress in the structure and the safety factor for that effort. The Two methods used during the investigation thatrndeveloped compromise: first, building a physical model in a test tunnel type 1g,whichwas properly instrumentedrnto record the variables of interest during the test, increased load. The second was developed with a numericalrnmodel using the finite element method, which simulated the increase of the forces acting on the ground surface.rnIn particular, the results presented in detail for two points in the section of the lining tunnel: the top or vault andrnlateral or hastial. The comparison of the results obtained by the two methods conclude that for the present studyrnthe result of the maximum value of internal stress in the structure calculated from numerical modeling showedrna difference of 1.64 times in excess compared with the record in the physical test. Regarding the analysis ofrnthe safety factor FS for maximum overload condition applied it was found that the numerical modeling methodrnexceeds 1.6 times the value obtained in the physical test.