ACI Global Home Middle East Region Portal Western Europe Region Portal
Email Address is required Invalid Email Address
In today’s market, it is imperative to be knowledgeable and have an edge over the competition. ACI members have it…they are engaged, informed, and stay up to date by taking advantage of benefits that ACI membership provides them.
Read more about membership
Learn More
Become an ACI Member
Topics In Concrete
Home > Publications > International Concrete Abstracts Portal
The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.
Showing 1-5 of 12 Abstracts search results
Document:
SP108-09
Date:
August 1, 1988
Author(s):
B. R. Sullivan
Publication:
Symposium Papers
Volume:
108
Abstract:
A testing system which can accommodate up to seven samples simultaneously with computer-controlled data acquisition, analysis, and reporting is described. The system consists of seven core holders of the Hassler type which can handle cylindrical samples ranging from 1-1/2 to 4 in. in diameter and from 4 to 11 in. in length. Confining and driving pressures can be independently varied up to 4000 psi. The test medium can be either liquid or gas including brine, since all tubing and containers are stainless steel. Flow is determined by pressure increase in a collector tank for gas and change in liquid level in a pipette column for liquid. Four pressure transducers per core holder are used to monitor all pressure levels during a test. A computer-based data acquisition system is used to scan up to seven tests simultaneously and record all data on a disc. Upon termination of a test, flow and permeability are computed and plotted against time and a report is printed for the test. The data are saved permanently on the disk and a backup copy is transferred to a floppy disk for safe storage. Sample preparation, sealing, and testing procedures are explained. Data analysis and typical results are presented on salt cores and concrete samples.
DOI:
10.14359/3660
SP108-10
A. Bisaillon and V. M. Malhotra
Paper describes the modifications made to a previously developed CANMET test method to measure the permeability of concrete and discusses test results to determine the reproducibility of the test method. Briefly, the test method consists of measuring the uniaxial water flow through cylinders (125 mm high with a diameter of 150 mm) under a pressure of 3.5 MPa. A large number of concrete specimens with water-cement ratios of 0.65 and 0.80 were tested. A limited number of test specimens having w/c of 0.22 and 0.27 were also tested. Test results show that the within-batch variation for the test method is high, and this is probably due to the heterogenous nature of the concrete. For concrete with w/c of 0.22 and 0.27, there was no outflow of water, and this technique in the present form may not be suitable for measuring the permeability of very high strength concrete.
10.14359/3671
SP108-06
K. Schonlin and H.K. Hilsorf
For the determination of the permeability on concrete discs, a rapid test method has been developed. No special devices are required to fix the test apparatus to the specimen. Air permeability of the concrete can be measured within a period of about 15 min. Laboratory experiments show a close correlation between the measured permeability coefficient and the duration of curing, type of cement, w/c ratio and the content of fly ash.
10.14359/3608
SP108-11
D. Whiting
Study of permeability was made using six concrete mixtures ranging in water-to-cementitious material (w-c) ratio from 0.26 to 0.75. Concrete specimens were tested for permeability to water and air, permeability to chloride ions (rapid and long-term), volume of permeable voids, and porosity. Results confirm that permeability is a direct function of w-c ratio. The addition of silica fume results in even greater decreases in permeability than would be anticipated based solely on w-c ratio. A period of initial moist curing of at least seven days is essential for achieving low permeability. Results also indicate that rapid test procedures offer a reasonable alternative to more lengthy and complex conventional permeability tests.
10.14359/2186
SP108-01
J. F. Young
The permeability of hardened cement paste is reviewed with particular reference to the influence of pore structure. Permeability is usually modelled by applying D'Arcy's Law, although permeability measurements and pore size distribution determinations reveal the strong influence of large capillary pores (macropores) on flow through cement paste. The macropores form a continuous flow path within the paste. The effects of curing temperature, drying, and admixtures on permeability can be understood in terms of their influence on macropores. Paste containing fly ash shows anomalous behavior, which apparently arises from internal damage occurring during pore structure measurements. It appears that the presence of fly ash promotes the formation of a discontinuous macropore system that inhibits flow.
10.14359/2136
Results Per Page 5 10 15 20 25 50 100
Edit Module Settings to define Page Content Reviewer