| dc.description.abstract | This research used Danang sand as the representing material of in-situ reclaimed soil to investigate the properties of liquefaction and to evaluate the improvement effects attributed to using cement. A series of experiments have been done on a set of samples made by using wet tamping method. The set consists of samples having Danang sand for relative density (40%) and fine contents (10%) mixed with different cement contents (0.3%, 0.5%, 1.0%, and 2.0%). This research having two different blend water for making up samples, distilled water and artificial seawater. The degree of salt for this research is 35‰ which making up artificial seawater we need. After curing for 3, 7, 28 or 56 days, the unconfined compression tests and dynamic triaxial tests were conducted.
According to the results of unconfined compression tests, it is understood that chlorine ion will improve the strength of cement treated sand. Before 28-day curing, the strength of samples mixed with artificial seawater are higher than that of the samples mixed with distilled water. But when curing period is 56 days, the strength will be a little lower for samples mixed with artificial seawater. This result is opposite to that of the samples mixed with distilled water.
According to the results of dynamic triaxial tests, when the curing period is 7 days, adding cement of 2% mixing rates to the sand will improve the liquefaction resistance. For the case of 28-day curing, adding cement of 1% mixing rates to the sand will also have the same effect. | en_US |