Title:
Influence of microcracking on the mass transport properties of concrete
Author(s):
H. R. Samaha and K. C. Hover
Publication:
Materials Journal
Volume:
89
Issue:
4
Appears on pages(s):
416-424
Keywords:
absorption; chlorides; durability; microcracking; permeability; radiography; Materials Research
DOI:
10.14359/2585
Date:
7/1/1992
Abstract:
Investigated the influence of load-induced microcracking on the transport properties of concrete. Concrete cylinders were loaded to different levels of compressive stress, then tested by the rapid chloride permeability test and two additional tests of moisture movement. The neutron radiography technique was used to record the incidence of microcracking resulting from applied loads. On the basis of this work, it appears that mass transport properties of concrete are generally not affected after one cycle of uniaxial compressive loading to below 75 percent of the maximum load capacity of the concrete, but for higher load levels, mass transport properties can be enhanced by as much as 20 percent. Shrinkage associated with oven-drying seems to have a more damaging effect on the concrete microstructure than compression loading to maximum capacity. The results of the rapid chloride permeability tests did not correlate with the compressive strength of the concrete, suggesting that strength alone does not necessarily reflect durability of concrete. This paper is a digest of the project reports filed with the Concrete Research Council of ACI.