Enhanced Performance of Stabilized By-Product Gypsum (05-0910)
Mingjiang Tao, Worcester Polytechnic Institute
Zhongjie Zhang, Louisiana Department of Transportation and Development

Blended calcium sulfate (BCS), a by-product gypsum blended with lime or limestone, has been used as a base course on some Louisiana¡¯s highways. Although it has high strength in dry conditions, its poor water resistance has largely limited its application on highway pavements. A series of laboratory tests identified the factors that dictate the strength development of non-stabilized BCS. BCS was subsequently stabilized with various cementing agents to ameliorate its water resistance. The mechanical properties of stabilized BCS, such as unconfined compressive strength, water resistance, volumetric expansion, and durability, were also evaluated. Finally, recommendations were made for the application of stabilized BCS as a base course.