Innovation in Injection Grouting Methods: New Doctor of Civil Engineering from the Faculty of Engineering at Unhas Achieves a Breakthrough in Soil Stability
Gowa, August 15, 2025 – The Faculty of Engineering at Hasanuddin University (FT-UH) once again conferred a Doctor of Civil Engineering degree during an Open Doctoral Defense held at the FT-UH Campus in Gowa. The dissertation research presented at this session addressed the topic “Soil Stabilization Using Waterglass and Sulfuric Acid with the Grouting Injection Method,” which offers an innovative approach to enhancing soil bearing capacity to support construction in high-risk areas.
The defense began at 10:00 a.m. WITA and was presided over by the Dean of the Faculty of Engineering at Unhas, Prof. Dr. Eng. Ir. Muhammad Isran Ramli, S.T., M.T., IPM., ASEAN.Eng., who served as Chair of the Defense on behalf of the Rector of Hasanuddin University. The examination committee consisted of academics and civil engineering experts, namely the Supervisor, Prof. Dr. Ir. Abd. Rachman Djamaluddin, MT; Co-Supervisors, Prof. Ir. Achmad Bakri Muhiddin, M.Sc., Ph.D., and Dr. Ardy Arsyad, ST., M.Eng.Sc.; External Examiner Prof. Ir. Muhammad Suradi, M.Eng., ST., Ph.D., as well as internal examiners Prof. Dr. Eng. Ir. Tri Harianto, ST., MT., IPU., AER; Prof. Dr. Eng. Ir. Rita Irmawaty, ST., MT.; and Dr. Eng. Ir. Bambang Bakri, ST., MT., IPU., ASEAN.Eng.
This dissertation investigates the effectiveness of using a combination of waterglass and sulfuric acid as grouting materials to reinforce non-cohesive soil, under both saturated and unsaturated conditions. This method has been proven to improve soil technical parameters, such as cohesion, internal friction angle, and permeability, while simultaneously reducing the risk of collapse in micro-tunneling projects or construction in landslide-prone areas.
The research results indicate that specific variations in the composition of the grouting material are significantly capable of rapidly forming a reinforcing wall, filling soil pores, and increasing bearing capacity. Thus, this method is considered efficient, fast, and capable of reducing reliance on conventional stabilization techniques that require more time and cost.
Based on the examination results and the evaluation committee’s assessment, the doctoral candidate was declared to have passed with the grade “Highly Satisfactory” and officially received the degree of Doctor of Civil Engineering.
In his remarks, the advisor, Prof. Dr. Ir. Abd. Rachman Djamaluddin, MT, stated that this research makes a tangible contribution to the development of soil stabilization methods in Indonesia, particularly to support infrastructure projects in areas with high geotechnical risks. “This injection grouting method, based on a combination of waterglass and sulfuric acid, offers a faster, more effective, and more economical solution for reinforcing soil in the field,” he said.