EXPERIMENTAL STUDY OF THE EFFECTS OF BOLT TIGHTNESS ON THE BEHAVIOUR OF MERO-TYPE DOUBLE LAYER GRIDS

摘要

The main objective of the present work is to study the effects of bolt tightness on the response of a MERO-type double layer grid. A full-scale double layer grid was tested with three different support conditions and four different levels of bolt tightness. In each case, all the bolts of the grid were tightened to a specific degree of tightness. Then, deflections of a number of nodes were measured for a central point load. The load-deflection responses of the test grid show that the degree of bolt tightness has a significant effect on the behaviour of the grid. The experimental results indicate that the load-deflection responses of a MERO-type double layer grid lie in a region whose upper and lower limits depend on the support conditions of the grid.