LABORATORY TESTS OF CEMENT STABILIZED & SOLIDIFIED CORAL REEF AND SAND FOR USE OF HIGHWAY PAVEMENT

In order to resolve the issue of intensive resource during the reef highway construction, it is proposed to using cement stabilized/solidified coral reef and sand as pavement base materials. The experiments are carried out for their unconfined compressive strength, splitting strength, modulus of resilience, water stability, dry shrinkage and temperature shrinkage and examine their strength, stiffness, water stability and shrinkage characteristics. This research would provide theoretical basis and data foundation for the subsequent construction of reef engineering. The results show that under the standard curing conditions, compressive strength and splitting strength increase with the increase of cement dosage at the same curing age, and those strengths were also improved along with the age growth under the same cement dosage. The compressive strength follows an approximate liner relationship with the cement dosage. Modulus of resilience increases with the rising cement dosage, while the growth rate gradually decreases. Under the same age, saturation strength of the sample is relatively lower than the standard strength. The higher dosage of cement and the longer curing age induce lower intensity loss rate and higher performance of softening resisting. After 28 day curing, the strength loss rate increases 93% and the softening coefficient increases 101%, respectively, as the cement dosage decrease from 6% to 3%. For the dry shrinkage test, the water loss rate and dry shrinkage strain increase with rising the age and cement dosage. After 180 day curing, water loss rate and the drying shrinkage strain decrease 1.35 times and 1.27 times, respectively, as the cement dosage increase from 3% to 6%. The temperature shrinkage tests show that shrinkage strain and coefficient increase with rising cement dosage, whereas they fluctuate along the temperature drop. The temperature range of 30~45℃ is the most disadvantage reef construction of highway pavement, so high temperature construction needs to be avoid.