An equivalent substitute material for frost heave cracking of fractured rock and its preparation method

Abstract

The invention provides an equivalent substitute material for frost heaving and cracking of cracked rocks, the substitute material includes rock cracking agent CaO, Ti-CaO, Co-CaO, Zn-CaO or Ni-CaO, Portland cement with strength greater than 32.5 and / or Or a mixture of high alumina cement, β-type hemihydrate gypsum, a mixture of oxalic acid, citric acid or benzenesulfonic acid and hydrogen peroxide or sodium peroxide, and polyurethane, polyvinyl alcohol or lignosulfonate in the water reducing agent. Stir the material with water at a temperature of 10-25°C to prepare a slurry, continue to stir until the slurry solidifies, and control the expansion rate of the solidification to 9%, and the elasticity of the solidification is 500-550MPa, which is the cracked rock jelly. It is an equivalent alternative material for expansion cracking, and it is applied to rocks with cracks and cracks due to freeze expansion. The elastic modulus of the solidified body of the mixture is similar to that of ice, and after the slurry is solidified, it will have the same deteriorating effect on the rock as when water freezes. The deformation and failure parameters of the substitute material can ensure that the expansion material will not undergo its own fracturing failure under the condition of an expansion rate of 9%.

Description

technical field [0001] The invention relates to an equivalent substitute material for frost heave cracking of cracked rocks, which is applied to the equivalent simulation of cracked rocks containing cracks. Background technique [0002] The rock freeze-up cycle is a common natural phenomenon. The freeze-up has a great influence on the physical and chemical properties of the rock, and the rock is often used as the basis of practical engineering. Therefore, it is extremely important to study the change law of the rock properties with the freeze-up cycle. meaning. [0003] Conventional frost-heave tests can only be performed on standard specimens in the laboratory, but it is difficult to conduct field tests on large-scale rock mass in the field. The main reasons are: (a) the existence of large cracks; The water problem is not easy to solve, and it is difficult to achieve the effect of frost heaving under water retention in cracks. (b) It is difficult to find large-scale equip...

AI Technical Summary

Problems solved by technology

[0006] In order to solve the problems that current conventional freeze-up tests use freezing, multiple cycle times are long, the effect is not obvious, and large-volume rocks cannot be frozen in-situ in the field, etc., a mixture composed of rock-cracking agent and cement is prepared. The expansion rate curves of different mix ratios are drawn in the test, and the mixtures with different expansion rates are selected, and then the test of accelerated deterioration of fractured rocks (mixtures with expansion rates greater than 9%) is carried out.

Images