Research and application of composite cement in Vietnam (стр. 2 )

The results of test for the materials showed: Portland cement (with 3.5% SO3) in accordance with PC 50 of TCVN 2682: 2009; FA is class F - FA in accordance with ASTM C618 ; GGBFS is according to TCVN 4315: 2007 (similar GOST 3476); the main phases of FA are amorphous and a little of quartz, GGBFS is amorphous; .

Composite cement is made from the above mentioned materials with following mix proportions: clinker content from 20 ÷ 60%; GGBFS content 40 ÷ 80%; FA content: 10 ÷ 30%; lime stone content: 5 and 10%; SO3: 3.5 ÷ 5%. Total 113 mix proportions were studied, however in

this paper described of 33 mix proportions with ratio (clinker/(clinker +GGBFS) = 30%) are presented in Table 4.

Experiments including: standard test methods and other research methods to test strength development, Heat of hydration of cement, expansion of mortar bar in water, aggressive solutions, autoclave, expansion of mortar bar, particle size analyze of powder materials (Machine: COULTER LS Particle Size Analyzer 3.00.40), identification of reaction products by X-ray (Machine: D8.ADV), SEM; determination of Cl - and SO3 penetration by EPMA method, etc.

Table 4. Mix proportions with (clinker/clinker + GGBFS) = 30%.

TT	Mix ID	Content of the components, % mass	SO3, %
Clinker	GBFS	FA	Limestone
1	M025	28.50	66.50	0.00	5.00	3.50
2	M89	25.50	59.50	10.00	5.00	3.50
3	M90	22.50	52.50	20.00	5.00	3.50
4	M91	19.50	45.50	30.00	5.00	3.50
5	M026	28.50	66.50	0.00	5.00	4.00
6	M92	25.50	59.50	10.00	5.00	4.00
7	M93	22.50	52.50	20.00	5.00	4.00
8	M94	19.50	45.50	30.00	5.00	4.00
9	M027	28.50	66.50	0.00	5.00	4.50
10	M95	25.50	59.50	10.00	5.00	4.50
11	M96	22.50	52.50	20.00	5.00	4.50
12	M97	19.50	45.50	30.00	5.00	4.50
13	M028	28.50	66.50	0.00	5.00	5.00
14	M98	25.50	59.50	10.00	5.00	5.00
15	M99	22.50	52.50	20.00	5.00	5.00
16	M100	19.50	45.50	30.00	5.00	5.00
17	M029	27.00	63.00	0.00	10.00	3.50
18	M101	24.00	56.00	10.00	10.00	3.50
19	M102	21.00	49.00	20.00	10.00	3.50
20	M103	18.00	42.00	30.00	10.00	3.50
21	M030	27.00	63.00	0.00	10.00	4.00
22	M104	24.00	56.00	10.00	10.00	4.00
23	M105	21.00	49.00	20.00	10.00	4.00
24	M106	18.00	42.00	30.00	10.00	4.00
25	M031	27.00	63.00	0.00	10.00	4.50
26	M107	24.00	56.00	10.00	10.00	4.50
27	M108	21.00	49.00	20.00	10.00	4.50
28	M109	18.00	42.00	30.00	10.00	4.50
29	M032	27.00	63.00	0.00	10.00	5.00
30	M110	24.00	56.00	10.00	10.00	5.00
31	M111	21.00	49.00	20.00	10.00	5.00
32	M112	18.00	42.00	30.00	10.00	5.00
33	M113	100% OPC	0	0	0	3.50

2.4 Results and Discussion.