พฤติกรรมหลังการวิบัติของคันดินบนชั้นดินโคลนบริเวณปากแม่น้ำ / ประสม ณ ชาตรี = Performance of post failure embankment on mud at delta area / Prasom Na Chatre
Embankment on very soft clay can be constructed by various different methods. This research aims to study the behavior and settlement of the embankment constructed on mud foundation at delta area. Soil profile consists of 6 m. thick mud with water content between 110 to 130 percent and the undrained shear strength increasing linearly with depth between 2.55 to 8.55 kN/m2. The embankment was reinforced by geotextile, bamboo and timber piles. Three test sections of embankment were constructed in stages from 1 m high 2 m high and end at 3 m. high. The vertical and lateral ground displacement during and after construction were measured by means of surface settlement markers installed on geotextile. The embankment constructed on mud with reinforced by geotextile, bamboo and timber piles can be constructed even the bearing capacity failure on mud foundation was induced. The reinforced pattern can reduce the lateral soil movement than case of non-reinforce embankment because the mud foundation was replaced by filled embankment and forming the compacted soil bulb beneath the embankment. The settlement at centerline of embankment (ρi , m.) during construction is in function of embankment surcharge ( q , kN/m2) as follows: ρi = 0.0041 q 2 +0.2542q + 0.0336. The non-reinforced embankment shows a very low safety factor against overall stability failure. The safety factor against bearing capacity failure on mud foundation for case of non-reinforcement with geotextile, bamboo and timber pile is in the order of 0.22. The embankment with reinforcement of geotextile, bamboo and timber piles induces the compacted soil bulb in the mud foundation and lead to increase the safety factor against stability of embankment. The safety factor for case of 3 m. high embankment with reinforcement is in the order 1.11
