Rapid Set, High-Early Strength, Non-Excavatable Flowable Fill

摘要

A high-flow, rapid-set, non-excavatable CLSM mixture called ZOOM was developed for applications where time was critical using normal concrete component materials. The following criteria were established for the ZOOM mixture: 1. Pass the ASTM D 6024 in 6 h or less regardless of subgrade moisture conditions 2. Little or no bleeding or shrinkage 3. Flow as per ASTM D 6103 greater than 222 mm 4. Greater than 207 kPa compressive strength as per ASTM D 4832 in 24 h 5. Be able to perform using a wide variety of Tennessee aggregates The development of the ZOOM mixture began in the laboratory in May 2002 using Ohio River Sand (ORS). Subsequently, the mixture proportions were adjusted to produce the desired plastic and hardened properties with other Tennessee fine aggregates. Three successful field demonstrations using different fine aggregates were held across Tennessee in the fall of 2002. ZOOM CLSM met compressive strength development and time of suitability for load application performance criteria at every field demonstration. Plastic properties were adequate but failed to meet the established criteria on two occasions. Fine aggregate properties such as gradation and angularity were found to dictate mixture proportions required to achieve flow, air content, and bleeding characteristics. Average air temperature and CLSM air content were found to be important to time of suitability for load application. The research effort was co-sponsored by the Tennessee Department of Transportation and the Tennessee Ready Mixed Concrete Association