Table 2.

Elemental composition and densities of concrete samples.

Elements	C-0	C-B5	C-B7	C-N5	C-N10	C-N15
C	25.44	23.07	22.12	24.49	21.5	20.2
O	46.95	45.5	46.32	47.85	46.05	47.05
Na	0.57	0.33	0.23	0.35	0.2	0.28
Mg	0.77	0.7	0.64	0.77	0.74	0.81
Al	1.96	1.75	1.83	2.51	2.36	2.14
Si	8.73	10.55	11.51	8.73	9.3	8.3
S	0.86	0.82	0.79	0.8	0.81	0.9
Ca	11.47	12.6	11.44	10.02	12.9	11.87
Fe	3.05	3.14	2.97	2.91	3.1	3.9
Bi	0	1.34	1.95	1.37	2.84	4.35
Total	100	100	100	100	100	100
Density, g/cm3	2.70	2.74	2.80	2.73	2.75	2.78