KORELASI ANTARA CBR RENDAMAN DENGAN PARAMETER FISIS PADA MATERIAL TIMBUNAN REKLAMASI LOKAL SAMARINDA

Abstract

Land development with reclamation embankment requires material that has fulfill prerequisite of granuler gradation in the form of 80% minimal sand and 20% maximum silt-clay, and another prerequisite is embankment compaction. The reclamation implementer on site that is generally want to know the embankment material fast and easily is just one of  density tests for example California Bearing Ratio (CBR), could be knew the other density parameters, that is dry unit weight  (g_d), void ratio (e) dan porosity (n)  with assumption saturated.

This research is carried out by means of laboratory test for using sand (passing no. 10 or 2 mm diameter)  picked  up from Sungai Mahakam Samarinda and silt-clay (passing no. 200 or 0,075 mm diameter) are taken from Gunung Lipan Samarinda. Sampel are made  5 variations with sand and silt-clay composition are 100% : 0%, 95% : 5%, 90% : 10%, 85% : 15%, 80% : 20% . Then,  material are tested  Modified Proctor compaction with 25 sampels (5 variations x 5 sampel/variation). The next step is a soaked CBR test as much 25 sampels with observing  swelling up to  four days . The last step is test of volumetric-gravimetri with 25 sampels.

The result of this research indicates that the greader CBR so the greader dry unit weight  (g_d), the less  void ratio (e) and porosity (n), and on the reverse. The biggest of  g_d value is obtained  from  85% sand and 15% silt-clay with a soaked CBR  is 16,61%. The result of this research are explained  that linier regresi equation related to soaked CBR with  fisis parameters are dry unit weight, CBR = 16,308. γ_d – 13,898 ;  void ratio, CBR = -42,341. e + 32,877  and  porosity, CBR = -85,273. n + 40,291. The equation between parameters is valid whenever it is used for the Samarinda’s local material with 80% minimum sand and 20% maximum silt-clay compositions.