USM .....what do you know about USM. USM is unwanted material at site. Its part of geotechnical scope. Normally the USM will be removed from site to the contractor own dumping area. And its depend to how severe and the depth of USM. The depth of USM and type of treatment has been stated in Construction Drawing. Some of the treatments are :
a. Remove and replace with sand and after that continue with normal filling. Normally for depth around 1.5m to 2m. To know the depth of USM do a MP test until 40 blows 3 consecetive . Do Atterberg Limit Test to get a LL, PL to confirm the material weather USM or not eventhough drawing has stated.
b. Remove and Replace with sand sometime install PVD and after that install with instrumentation such as pneumatic piezometer, settlement gauge, inclinometer and continue filling. Reading will be taken every 300mm of filling. And some cases it will be rest for 7 days before continue with next filling. After complete a filling add 1.5m surcharge and monitor settlement for six month.
c. Dynamic Replacement
No comments:
Post a Comment