A
fly ash solidification foamed material for preventing
coal spontaneous combustion and a preparation method thereof. The
fly ash solidification foamed material comprises the following ingredients, by weight: 40-60 parts of water, 100 parts of
fly ash, 25 parts of complex
powder for chemically self-producing gas, 1-5 parts of an accelerator, 1-4 parts of an activator, 0.6-1.5 parts of a
water reducer, and 0.5-1 parts of a foam stabilizer. The preparing method comprises: adding the foam stabilizer in water and stirring to form a uniform foam solution; adding the fly ash, the complex
powder for chemically self-producing gas, the accelerator, the activator, and the
water reducer in a dry-blending mixer to form a blended
powder; and finally adding the blended powder into the uniform foam solution to obtain the fly ash solidification foamed material. The material of the invention is light in weight, safe and low in costs, and has strong crack penetration capability, adjustable solidification time, great
compressive strength, low heat
conductivity coefficient, and a good heat insulation effect; foam fluid can uniformly cover loose
coal-rock
mass;
carbon dioxide is released during a foaming reaction process to well dilute the
oxygen concentration in residual
coal space; and the operation technique is simple.