Negative Poisson’s Ratio Design And Mechanical Properties Of Reinforced Concrete

Reinforced concrete building structures may be affected by various types of accidental impact loads,such as heavy objects falling during construction,collision between vehicles,ship impact on piers and wave impact.Its short action period,high load strength and great damage to the structure are often an important feature of accident impact.Moreover,the main load-bearing components such as beams and columns also face the impact threat of various types of accidents.In some specific structural design process,we should fully consider the impact of these loads.At present,the research on the impact resistance of reinforced concrete structure is mostly based on the strength and toughness of reinforcement materials.In view of the impact resistance of reinforced concrete under dynamic load,this paper introduces negative Poisson’s ratio material into the field of concrete,designs concave reinforced unit structure and concrete composite,and makes negative Poisson’s ratio reinforced concrete.Through the design,it has negative Poisson’s ratio effect and hopes to have better mechanical properties and impact resistance.The results show that:Under bending static load,compared with square reinforced concrete,the fracture energy of six-ribbed and star-shaped reinforced concrete increased by 132 % And 181 %;And star-shaped reinforced concrete has better energy absorption capacity.Under impact compression,compared with square reinforced concrete,the absorption energy of sixribbed and star-shaped reinforced concrete is increased by 1.17 times and 1.23 times.Under the impact of the falling hammer,when the falling height of hammer is 1m,the impact resistance of six-ribbed reinforced concrete and star-shaped reinforced concrete can be increased by 1.7 times and 2.7 times;When the falling height is 2 m,the impact resistance of six-ribbed reinforced concrete and star-shaped reinforced concrete can be increased by 3.0 times and 6.0 times.Star-shaped reinforced concrete can effectively improve the impact toughness of concrete and the ability of absorbing impact energy after initial crack.The energy dissipation capacity of six-ribbed reinforced concrete and starshaped reinforced concrete is 2.0 times and 3.5 times of that of ordinary concrete,respectively.Under the impact load,both six-ribbed and star-shaped reinforced concrete have negative Poisson’s ratio effect,and with the increase of the concave angle of the reinforced structure,the deformation capacity of reinforced concrete increases,the elastic modulus increases,and the negative Poisson’s ratio decreases.The increase of the internal concave angle of the reinforced structure is more conducive to reduce the Poisson’s ratio.The energy absorption performance increases with the increase of the inner concave angle,and the negative Poisson’s ratio decreases with the increase of the inner concave angle,indicating that the negative Poisson’s ratio structure has better energy dissipation capacity,and its energy dissipation capacity is affected by the inner concave angle small,the energy absorption performance will be enhanced.