To overcome the problems of traditional vacuum preloading method

vacuum preloading and pneumatic fracturing are combined to reinforce the performance of ground improvement. The mechanism and construction procedures of the combined method are introduced firstly. The reinforcement effect of the combined method is validated through a pilot highway embankment on soft clay in Jiangsu

China. Comparing to the traditional vacuum preloading method

the combined vacuum preloading and pneumatic fracturing method would enhance the transfer efficiency of vacuum into deep soil layers and accelerate the dissipation of excess pore water pressure. Therefore

the strength increase of soft soil layers improved by the combined method is much larger than that of ground reinforced by the traditional vacuum preloading method. The combined method also can reduce the construction period than the traditional vacuum preloading method. The test results of cone penetration tests and engineering properties tests of soft soils also indicate the superior of the combined vacuum preloading and pneumatic fracturing method.