Research on Freeze-thaw Resistance of High-strength Porous Concrete

Because porous concrete is feature with a large pore structure and porosity,the freezing of water enriched in the pores in winter will have a greater impact on the performance of porous concrete.This paper puts forward the test method and evaluation index of the freeze-thaw resistance of porous conc...

Full description

Saved in:
Bibliographic Details
Main Authors: NIE Qingnian, YANG Yongmin, LIU Xiaofei, LI Haibo, LYU Kai
Format: Article
Language:zho
Published: Editorial Office of Pearl River 2021-01-01
Series:Renmin Zhujiang
Subjects:
Online Access:http://www.renminzhujiang.cn/thesisDetails#10.3969/j.issn.1001-9235.2021.01.009
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Because porous concrete is feature with a large pore structure and porosity,the freezing of water enriched in the pores in winter will have a greater impact on the performance of porous concrete.This paper puts forward the test method and evaluation index of the freeze-thaw resistance of porous concrete with reference to those of ordinary concrete,and systematically studies the effect of fly ash,slag,silica fume,fine sand and crack-resistant fiber on the freeze-thaw resistance of porous concrete.The results show that:The compressive strength of the prepared porous concrete is about 30.2~35.6 MPa for 28 days.The addition of fly ash,fine sand and fiber alone has no effect on the freeze-thaw resistance of porous concrete.Silica fume is beneficial to improve the freeze-thaw resistance.After adding 10% silica fume,when the number of cycles reaches 60,the dynamic elastic modulus can reach 66.8%,the mass loss rate is only 0.35%,and the freeze-thaw resistance index is 12.58.The porous concrete contains more connected pores,but it may still be damaged by volume expansion after water freezes.However,after adding silica fume,the freeze-thaw resistance of slurry is improved by increasing the amount of C-S-H gel,enhancing the adhesion between the interface and strengthening the interface.
ISSN:1001-9235