Lateral Movement of Khon Kaen Loess

Abstract

Loess in Khon Kaen University was a mixture between silt and clay. Then it was in dry condition can bear weight well, but then moisture content increase load capacity will decrease and collapse. Then it used in construction will consider horizontal displacement and vertical displacement. This research was studied the horizontal displacement and the ratio between horizontal displacement and vertical displacement () of Khon Kaen Loess soil in the field under natural and wet conditions. The four inclinometer tubes 6.0 m in length were installed (4 m in loess and 2.0 m in laterite). Then two holes are excavated away from the inclinometer tube 0.5 m. The first hole, which was 2.0 x 2.0 x 1.2 m, was used to install a footing. The second hole was a vertical cut of 4.5 meters in depth. Then the load was applied via the footing size 1.2 x 1.2 x 0.25 m and 1.2 m in depth. The results found that the settlement occurred under the stress of 20 t/sq.m were 10.66 and 75.38 mm under natural and wet conditions respectively, and moisture content under natural and wet were 5.8 and 20.4 respectively. Moreover, the horizontal displacement was the greatest at a depth of 1.5 m from the soil surface, 30 cm below the footing depth. But the horizontal displacement at a depth of 4.0 to 6.0 m was relatively constant because the inclinometer tube was in a laterite layer in both natural and wet conditions. The maximum horizontal displacement under the stress of 20 t/sq.m is 4.47 mm in natural condition and 17.51 mm in wet condition. The result presents that horizontal displacement at wet conditions was approximately 3-4 times greater than at natural conditions. Besides, the () of wet conditions was higher than natural conditions. The maximum () was 0.52 in wet condition, and the () at the failure of wet condition was 0.39. The maximum () was 0.419 in natural condition.