RESISTANCE OF SOIL-CEMENT EXPOSED TO SULFATES

THE DURABILITY IS ESTABLISHED OF SOIL-CEMENT EXPOSED TO SULFATE SALTS, AND ALSO THE DURABILITY OF SOIL-CEMENT MADE WITH SULFATE SOILS. THE FIRST PART OF THE STUDY WAS CONCERNED WITH THE RESISTANCE OF SOIL-CEMENT TO SULFATE ATTACK, WHEREAS THE SECOND PART WAS DESIGNED TO DETERMINE THE DURABILITY OF SOIL-CEMENT WITH SULFATE SALTS MIXED INTEGRALLY. SOME OF THE CONCLUSIONS OF THE STUDY WERE: (1) SOIL-CEMENT IS SUBJECT TO ATTACK OF SULFATE SOILS MUCH IN THE SAME MANNER AS CONCRETE, (2) SOIL-CEMENT SPECIMENS OF HIGH CEMENT CONTENTS ARE MORE RESISTANT TO THE ATTACK OF SULFATE THAN SOIL-CEMENT OF LOW CEMENT CONTENT, (3) CEMENT CONTENT OF RICHNESS OF MIX IS MORE EFFECTIVE IN PRODUCING A SULFATE-RESISTANT SOIL-CEMENT THAN THE TYPE OF CEMENT USED, (4) SOIL-CEMENT SPECIMENS MADE WITH COARSE-GRAINED SOIL, HIGH CEMENT CONTENT, AND SULFATE RESISTING CEMENTS PRODUCED THE MOST RESISTANT SOIL-CEMENT TO THE ATTACK OF SULFATE SALTS, (5) SMALL AMOUNTS OF SULFATE SALTS MIXED WITH SOIL- CEMENT AT THE TIME OF FABRICATION INCREASE THE COMPRESSIVE STRENGTH AND THE RESISTANCE OF THE SPECIMEN TO THE ACTION OF FREEZING AND THAWING, AND (6) HIGH CONCENTRATIONS OF SULFATE SALTS MIXED WITH SOIL-CEMENT AT THE TIME OF FABRICATION WILL CAUSE CRACKING, EXPANSION, AND REDUCTION IN COMPRESSIVE STRENGTH.