Procedia Engineering 193 ( 2017 ) 35 41


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Evaluation of Concrete Resistance to Freeze-thaw B

2. Materials and methods 

The tests and analyses were carried out on two concretes with varied structure and frost durability. The concretes 

were produced with the following constituents: 

•  cement CEM I 42.5 R (concrete A), CEM II/B-V 32.5 (concrete B), 

•  natural sand 0 - 2 mm,  

•  coarse aggregate - granite 4 - 8, 8 - 16 mm, proportion 45:55 (concrete A), - basalt 2 - 8, 8 - 16 mm proportion 

40:60 (concrete B),  

•  superplasticizer (SPL). 

Table 1 compiles the constituents and selected properties of concrete mixes being tested. The scope of tests 

included determining the compressive strength f’

cm

, water absorption n



w

 and the degree of freeze-thaw resistance on 

10x10x10 cm cubes. The specimens were cured in water for seven days before being left to air dry for 21 days.  

       Table 1. Composition and selected properties of concrete mixes. 

Constituent 

Content, kg/m

3

 (%m.c) 


Concrete A 

Concrete B 

Cement 360 

400 


Water 169 

159 


Sand 599 

670 


Coarse aggregate 

1216 


1117 

Superplasticizer  

(0.58) 

(1.00) 


W/C 0.47 

0.39 


gb  

2346 


2542 


38  

 Jerzy Wawrzeńczyk and Agnieszka Molendowska  /  Procedia Engineering   193  ( 2017 )  35 – 41 

 

The test for the resistance to internal cracking F150 (



ǻm, ǻR) according to PN-88/B-06250 [12] was carried out 

through direct freezing and thawing of the cubes by an ordinary method. Prior to starting freeze-thaw cycles, six 

(concrete B) or five (concrete A) specimens were saturated in water for seven days. Then, they were subjected to 

cyclic freezing at –18±2ºC for four hours and thawing in water at +18±2ºC for four hours. The number of freeze-

thaw cycles used was 150. The six reference specimens for compressive strength tests were stored at +18±2ºC 

during the entire period of freeze-thaw durability testing.  

The testing procedures involved evaluation of the specimens by visual inspection, measurements of the mass of 

cubes and determination of the relative decrease in strength 

¨R of the specimens subjected to freezing relative to the 

reference specimens after the last freezing. Concrete is regarded as resistant to frost if the mass loss is 5% or less 

and the compressive strength decrease is 20% or less. 


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