MIIX Virtua

Sinkholes and underground cavities are among the natural disasters, possibly due to either natural or human activities in the limestone area. Limestone is of rather wide occurrence in Malaysia, including the capital of Malaysia, Kuala Lumpur. The problem with limestone is its solubility and degradability when it reacts with rainwater, which is acidic. The vibration and disturbance due to nearby construction works might also trigger the sinkhole occurrence. There are a lot of sinkholes and underground cavities in the limestone area, which cause trouble for the residents, especially after heavy rains. This project introduces mitigation works using a smart solution of lightweight PU injection. PU is injected without demolishing the existing structure and without massive destruction in the construction area. Early detection of an underground cavity or sinkhole can be executed with the geophysical survey method. Laboratory tests on the strength of PU foam and the buoyancy were done, which indicated the high strength of PU foam comparable to concrete and its ability to resist buoyancy with the proper design. The polyol used in the production of PU is made of palm kernel oil, which is sustainable. This project is important to reduce accidents and ensure the safety of people while accommodating the structures and infrastructure that are built on the limestone area.