Effect of Dynamic Stress Produced by Rock Blasting on the Optimal Dimensioning of Room and Pillars in Horizontal Layers

Table 1

Data and geotechnical information.

Data for the mineral layer and the overlying rock	Pillar height	Hp	m	2
	Thickness of the mineral layer	tm	m	2
	Specific weight of ore	m	MN/m^3	0.031
	Specific weight of the overlying rock	r	MN/m^3	0.027
	Average pillar depth	Z	M	350
	Strength to compression of ore^∗1	σc	MPa	28.536
	Strength to compression of ore^∗∗1	σc	MPa	67.004
	Ore tensile strength^1	σt	MPa	−0.718
	Young’s module for ore^1	Em	MPa	53,544.54
	Cohesion	C	MPa	15.271
	Internal friction angle	φ	°	40.99
	Mineralized rock lithology		Quartzite	—
Data for the slab	Slab thickness	tslab	M	1
	Specific weight of the slab	s	MN/m^3	0.027
	Compression strength of the slab^∗∗1	σcs	MPa	9.228
	Tensile strength of the slab^∗∗1	σts	MPa	−0.464
	Young’s module for slab^1	Es	MPa	18,951.58
	Cohesion	Cs	MPa	4.179
	Internal friction angle	s	°	34.89
	Lithology of the rock that makes up the slab		Schist	—

Mineralized rock lithology Qzt Quartzite Lithology of the rock that makes up the slab Sch Schist.