LAUSR

Currently, the construction technology on soft ground reinforcement is very developed, including the technology of constructing soil-cement piles for soft soil reinforcement which is technically and economically effective and widely used. Another technology is using fly ash waste from thermal power plants to make fly ash- soil piles for soft ground reinforcement, which not only takes advantage of local materials but also reduces environmental pollution from operating thermal power plants. This paper introduces some research results on fly ash content and pile diameter when reinforcing soft ground. The authors modeled the calculation diagram of the soft ground reinforcement under the roadbed with the case of the hypothetical pile diameter D = 40cm; 50cm; 60cm corresponding to the content of fly ash 35%, 40%, 45%, the pile length L = 8m to handle all soft ground layers. The results show that when the pile length L = 8m, pile diameter D = 60cm corresponding to the fly ash content of 45%, the stability coefficient of K = 1.992 is larger than the allowable stability coefficient [K] = 1.4. In this case, the largest settlement strain S = 0.17m, meeting permissible settlement strain of the ground [S] = 0.3m. These results provide basement for the design, construction and operation management units to propose solutions to maximize the working ability of the materials, enhance the stability of the roadbed during exploitation.