Mechanical Properties of Grouted Crushed Coal with Different Grain Size Mixtures under Triaxial Compression

Table 2

Grouted specimens with different grain size distributions used in this research.

Grouted coal-crushed body	Grouted specimens with different confining pressure	Volume ratio to different grain size	Grain size mixtures	Similar initial porosity	Type of test
A1	A1-0; A1-5; A1-10; A1-15; A1-20	9.5–16 mm : 19–26.5 mm = 1 : 3	Small	0.4967	Triaxial
A2	A2-0; A2-5; A2-10; A2-15; A2-20	9.5–16 mm : 19–26.5 mm = 1 : 3	Small	0.4967	Triaxial
A3	A3-0; A3-5; A3-10; A3-15; A3-20	9.5–16 mm : 19–26.5 mm = 1 : 3	Small	0.4967	Triaxial
A4	The test specimens chosen from A4	9.5–16 mm : 19–26.5 mm = 1 : 3	Small	0.4967	SEM
B1	B1-0; B1-5; B1-10; B1-15; B1-20	9.5–16 mm : 26.5–31.5 mm = 1 : 3	Medium	0.5078	Triaxial
B2	B2-0; B2-5; B2-10; B2-15; B2-20	9.5–16 mm : 26.5–31.5 mm = 1 : 3	Medium	0.5078	Triaxial
B3	B3-0; B3-5; B3-10; B3-15; B3-20	9.5–16 mm : 26.5–31.5 mm = 1 : 3	Medium	0.5078	Triaxial
C1	C1-0; C1-5; C1-10; C1-15; C1-20	19–26.5 mm : 31.5–37.5 mm = 1 : 1	Large	0.5171	Triaxial
C2	C2-0; C2-5; C2-10; C2-15; C2-20	19–26.5 mm : 31.5–37.5 mm = 1 : 1	Large	0.5171	Triaxial
C3	C3-0; C3-5; C3-10; C3-15; C3-20	19–26.5 mm : 31.5–37.5 mm = 1 : 1	Large	0.5171	Triaxial
C4	The test specimens chosen from C4	19–26.5 mm : 31.5–37.5 mm = 1 : 1	Large	0.5171	SEM

Note. A1–A3 indicate the large grouted coal-crushed body (Figure 4(a)) with the same grain size mixtures for obtaining the average experimental values in this study; A1-0 to A1-20 mean the small grouted standard cylindrical test specimens (Figure 4(b)) cored from the same grouted coal-crushed body subjected to triaxial compressive strength tests under the confining pressure from 0 to 20 MPa; and the specimens chosen from A4 and C4 were used for SEM tests (not subjected to triaxial compressive strength tests).