Time response of two types of porous blocks for suction measurement

Abstract

Various types of porous blocks have been used for the indirect measurement of soil suction by various researchers, the usual experience being the importance of appropriate calibration, relatively low accuracy, and slow response. Two types of commercially available porous blocks were used. They were placed in samples undergoing either drying or inundation. Porous blocks were placed always with a tensiometer so that at the range of suctions measured by the tensiometer a comparison could be made between the response of the tensiometer and the porous block. The tests performed involved both slow drying in atmospheric conditions and fast inundation due to wetting. The experience gained from the tests performed is that in the three cases examined and contrary to common experience reported in the literature, the response of the porous blocks used was comparable to that of conventional tensiometers if not in fact faster.