Bond-slip model between steel bars and nano-SiO2 and PVA fiber reinforced geopolymer mortar

Abstract

The invention discloses a bond-slip model between steel bars and nano-SiO2 and PVA fiber reinforced geopolymer mortar. The bond-slip model between steel bars and nano-SiO2 and PVA fiber reinforced geopolymer mortar is characterized by wiping out a plurality of test pieces with the same SiO2 content and different dosage of PVA fibers, measuring the size, and calculating the shearing area of the test pieces; placing the test pieces in the middle position of a lower bottom plate, so as to cut the lower end of each test piece to enable the lower end of the test piece to contact the lower bottom plate and enable the upper end of the test piece to contact a loading plate to form a shear of the test piece, aligning the center of the test piece with the center of a lower platen of an electro-hydraulic three-axis servo test machine, starting the electro-hydraulic three-axis servo test machine, and uniformly, continuously and slowly loading; and loading in a mode of mixed control of load gradingand deformation grading, when the test piece is damaged by shearing, resetting the instrument, recording the damaged load and the damaged position, and calculating the shearing strength while the bonding strength is the shearing strength. The bond-slip model between steel bars and nano-SiO2 and PVA fiber reinforced geopolymer mortar reduces maintenance costs, realizes environmental optimization and prolongs the service life of the structure in engineering construction.

Description

Technical field [0001] The invention relates to the field of model building of inorganic polymer materials, in particular to a steel bar and nano SiO 2 Bond slip model between PVA fiber reinforced polymer mortar. Background technique [0002] Concrete and mortar are widely used materials in water conservancy engineering and civil engineering, and play a key role in engineering construction. As time goes by, many concrete structures in humid or industrial environments have experienced different degrees of corrosion damage , Resulting in a decline in the durability of the structure, resulting in many unfavorable hidden dangers, urgent local repair and reinforcement. Cement mortar has become the most widely used concrete repair and reinforcement material due to its low cost, convenient construction, and stable properties. However, traditional cement mortar has many inherent defects, such as low toughness, low tensile strength, and insufficient durability. , Easy to crack, etc., if ...

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Problems solved by technology

[0002] Concrete and mortar are widely used materials in hydraulic engineering and civil engineering, and play a key role in engineering construction. Over time, many concrete structures in humid environments or industrial environments have suffered corrosion damage to varying degrees , leading to a decline in the durability of the structure, and many unfavorable hidden dangers, it is urgent to carry out local repair and reinforcement

Cement mortar has become the most widely used concrete repair and reinforcement material due to its advantages of low cost, convenient construction, and stable properties. However, traditional cement mortar has many inherent defects, such as low toughness, low tensile strength, and insufficient durability. , easy to crack, etc., if it is used as a repair material for concrete structures, it will inevitably cause problems such as weak interface bonding and easy cracking, leaving potential safety hazards, while geopolymers have good high temperature resistance, high strength, and corrosion resistance. At the same time, geopolymer is a kind of highly brittle inorganic gelling material. Geopolymer mortar and cement mortar have the same problems of high brittleness, low toughness and low deformation resistance. Therefore, using The incorporation of PVA short fibers into geopolymer composites can enhance the toughness of geopolymer-based composites, and change the failure mode of composites from brittle failure to ductile failure. The modified geopolymer mortar is used as a repair material to improve the performance of new and old materials. The bonding performance of the concrete joint surface, due to the different materials of new and old concrete, its drying shrinkage deformation and temperature deformation are not coordinated, which is extremely unfavorable for the work of the two. In the existing technology, the accuracy of the bond-slip model is low and cannot be guaranteed. Building Safety in Engineering Construction

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