Cement-Stabilized Granular Volcanic Ash Materials for Construction of Low-Traffic Roads in Yemen

Table 2

Chemical composition of cement and GVA.

Composition	Average value
	Amran portland cement % [42]	Black GVA % [43]	Red GVA % [44]
SiO2	21.8	47.2	46.6
Al2O3	—	19.2	16.7
Fe2O3	2.65	11.6	12.5
CaO	65.7	8.1	9.3
MgO	2.64	4.2	7.8
K2O	0.0	1.2	0.9
Na2O	0.65	4.8	2.7
SO3	—	0.03	0.1
P2O3	—	0.5	0.4
TiO2	—	1.7	2.1
LOI	1.2	0.5	0.7