Title: Durability of Mt. Pinatubo Blended Cement Mortar Under Accelerated Weathtering Conditions

Author(s): G. Shimizu, B. Verdejo and P. Jorillo Jr.

Publication: Symposium Paper

Volume: 170

Issue:

Appears on pages(s): 1603-1622

Keywords: Acids; admixtures; alkali-silica reactions; concretes; durability; mortars (materials); pozzolans; shrinkage; sulfate attack.

DOI: 10.14359/6894

Date: 7/1/1997

Abstract:
This paper describes the results of the study on the durability evaluation of Mt. Pinatubo blended cement mortar under accelerated conditions of acidic, sulphate and alkali-silica reactive regimes. Various types of ejecta materials and percentage cement replacements (i.e., 10, 20, 30, 40, 50, 60, 70, and 80%) were investigated to determine the optimum type and proportion in a cement-based mortar matrix based on the criteria of strength, dimension stability, resistance to alkali-aggregate reaction and severe environmental conditions. Test results indicated that the use of Pinatubo pozzolans are effective mineral dmixtures against acidic, sulphate, alkali-aggregate reactions. Optimum pozzolans proportions ranges from 40-60% under varying conditions. Dimension stability and shrinkage properties of mortar with Pinatubo pozzolans are basically comparable to plain portland cement mortar, indicating stability of the pozzolans as a concrete constituent material. Alkali-aggregate reactivity test of selected samples of Pinatubo aggregate also showed innocuous characteristics.