{'fraction_non_alphanumeric': 0.03152173913043478, 'fraction_numerical': 0.014130434782608696, 'mean_word_length': 5.308219178082192, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Study on Frost Resistance of Nano SiO2 Cement Concrete

According the test, this paper discussed the relationships among nano SiO2 content of nano SiO2 cement concrete ,air content, water-cement ratio and frost resistance property.Meanwhile, the relationship among the bubble parameter, structure of holes and the frost resistance is primarily discussed. The results show that the concrete mixed with some nano SiO2, with the increase of impervious holes in hardened cement paste, compared with ordinary concrete,both the ability of freezing-thawing resisting and compression strength will have an improvement. What’s more, when mixed with the air-entraining agent, freezing-thawing cycles number will have an obvious increase.When water-cement ratio is 0.35-0.39, the ability of frost resisting is very high but when water-cement ratio is larger than 0.39, freezing-thawing resisting performance is substantial decline.