ABOUT THE 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.

International Concrete Abstracts Portal

Showing 1-5 of 14 Abstracts search results

Document: 

SP249-01

Date: 

March 1, 2008

Author(s):

Thomas E. Stanton

Publication:

Symposium Papers

Volume:

249

Abstract:

Due to copyright issues, this paper is only available by purchasing the SP-249.

Tests have demonstrated that excessive expansion of concrete may occur through chemical reactions between cements of relativley high alkali content and certain mineral constituents in some aggregates, such as certain types of shales, cherts, and impure limestones found along the coast of California between Monterey Bay on the north and Los Angeles County on the south. A new test procedure is described in this paper through which it is possible, in a comparatively short time, to develop the deleterious characteristics of cement-aggregate combinations similar to those reported in the California study. The procedure consists of curing the specimens in sealed containers at normal temperatures.

DOI:

10.14359/20122


Document: 

SP249-05

Date: 

March 1, 2008

Author(s):

D.A. Abrams

Publication:

Symposium Papers

Volume:

249

Abstract:

A discussion preceding a demonstration of actual field proportioning of concrete by Stanton Walker. Mr. Walker has prepared a resume of the methods used which appears on p. 182 of this volume.

DOI:

10.14359/20126


Document: 

SP249-04

Date: 

March 1, 2008

Author(s):

H.F.W. Taylor

Publication:

Symposium Papers

Volume:

249

Abstract:

Due to copyright issues, this paper is only available by purchasing the SP-249.

Hydrous calcium silicates prepared at room temperature appear amorphous, but X-ray photographs show that compounds are formed having a considerable degree of crystalline character. Essentially the same product, calcium silicate hydrate (I), can be obtained by the action of water on tricalcium silicate, by double decomposition of calcium nitrate and sodium silicate, or by reaction of calcium hydroxide solution with silica gel, although crystallisation is more mared in the first cae. The composition of this phase varies between approximately CaO,SiO2,aq. and 3CaO,2SiO2,aq. Without significant change in X-ray pattern. The phase relationships between solid and solution have been investigated and are sufficiently reproducible to suggest that the results represent a fair approximation to equilibrium conditions. A second phase, calcium silicate hydrate (II), with a composition in the neighbrourhood of 2CaO,SiO3,aq. And an X-ray pattern differeing only slightly from the above, has been obtained by decomposition of tricalcium silicate and probably exists in equilibrium with calcium hydroxide solutions containing over 1-13 g./l. of CaO. A tentative interpretation fo the X-ray data of calcium silicate hydrate (I) suggests a layer structure, possibly showing some similaritites to the clay minerals.

DOI:

10.14359/20125


Document: 

SP249-03

Date: 

March 1, 2008

Author(s):

R.S. Barneyback Jr. and S. Diamond

Publication:

Symposium Papers

Volume:

249

Abstract:

Due to copyright issues, this paper is only available by purchasing the SP-249.

A device is described that has been used for several years for expression of pore solution from hardened portland cement pastes and mortars. Particulars with respect to the design, fabrication, and operation of such equipment are given, and methods for the analysis of the resulting small volumes of pore solutions are briefly discussed. It is believed that the compositions of the pore solutions obtained are representative of that of the bulk of the pore solution within the paste or mortar from which the solutions have been obtained.

DOI:

10.14359/20124


Document: 

SP249-02

Date: 

March 1, 2008

Author(s):

R.H. Bogue

Publication:

Symposium Papers

Volume:

249

Abstract:

Due to copyright issues, this paper is only available by purchasing the SP-249.

The bases ofr a calculation of the compounds present in Portland cement from chemical analyses are presented. Arithmetical and diagrammatical methods are given for such a calculation. The compounds considered are 4CaO.Al2O3.Fe2O3, 3CaO.Al2O3, 2CaO.SiO2, 3CaO.SiO2, uncombined MgO, uncombined CaO, and CaSO4. Other components thatn those included in these compounds are not at present considered as their forms of combination are not known.

DOI:

10.14359/20123


123

Results Per Page