CMC APPLICATION AND PERFORMANCE UNDER HIGH RISE BUILDING WITH COMBINED RAFT FOOTING SYSTEM CASE STUDY: PELLETING STRUCTURE WITH 140 M HEIGHT

• Main Author: Rian Nugraha, Yudhistira
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/53388
• Institution: Institut Teknologi Bandung

In foundation design for high rise building, sometimes we need to solve commonly three soil layer problem i.e: soft soil layer, medium stiff/dense layer, and bed rock layer. As solution to that problem, geotechnic designer can easily recommend bored pile. But we just not realize that somehow bored pile is not efficent solution, given that concrete and steel reinforcement requirement are substantial for that conventional foundation system. Along with vast soil improvement technology development, just arise new solution by returning into shallow/footing foundation concept which overlying on reinforced soil volume. CMC or Controlled Modulus Column is one of soil improvement technology that to be considered. By means of this combined system between footing and CMC could be more cheap solution since we can minimize concrete and steel requirement significantly. Yet, on the other side there is one more failure possibility on this system when seismic load worked predominantly. Interaction between surrounding soil and CMC semi rigid inclusion should be in one rigid body so that when being acted by seismic load, foundation system remain together without any resistance in both column and surrounding soil. This research designed based on analytical method which reference to ASIRI National Project. Case study is industrial building with 140 m height that implementing raft combined foundation system and CMC. Structure inertial load gained from one signficant load combination. Axial load then subsequently share into stress portion of column and soil which is enabling deformation on each element and next to be considered as one improvement system. Meanwhile, lateral load that is addition of kinematic effect by seismic motion and structure inertial load which generate lateral displacement of soil that modeled as free-field motion. Soil lateral displacement then induced response to the column in term of bending moment, shear and reaction curve that obtained numerically according theory of beam on elastic foundation.