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CN-122020990-A - Prediction method for splitting tensile strength of concrete

CN122020990ACN 122020990 ACN122020990 ACN 122020990ACN-122020990-A

Abstract

The invention belongs to the field of concrete, and particularly discloses a method for predicting splitting tensile strength of concrete. In the prediction method of the invention, the formula for calculating and determining the splitting tensile strength of the concrete relates to the maximum particle size of rubber particles in the aggregate of the prepared concrete raw material Minimum particle size of rubber particles in aggregate Volume ratio of rubber particles in aggregate Particle size coefficient of rubber particles 、 And the maximum particle size coefficient of rubber particles in the aggregate The prediction method disclosed by the invention can simultaneously consider the synergistic effect of the particle size interval and the substitution rate of the rubber particles in the concrete raw material, can provide a clear strength prediction range in a design stage, is beneficial to optimizing aggregate selection and material parameter configuration, and improves design efficiency and proportioning reliability.

Inventors

  • Mo Jinxu
  • REN FENGMING
  • SUN RUIMING
  • YU ZHIWEI
  • Lai Mianheng
  • TIAN SHIYU
  • ZHOU WENMEI
  • CHEN BUQING
  • GUO SHAOZU

Assignees

  • 东莞理工学院
  • 广州大学

Dates

Publication Date
20260512
Application Date
20260108

Claims (10)

  1. 1. The method for predicting the splitting tensile strength of the concrete is characterized by comprising the following steps of: S1, preparing concrete, wherein the raw materials of the concrete comprise gel materials and aggregates, the aggregates comprise rubber particles and inorganic aggregates, and the volume ratio of the rubber particles in the aggregates is obtained Maximum particle diameter of rubber particles in the aggregate Minimum particle size of rubber particles in the aggregate ; S2, calculating and determining the splitting tensile strength f st of the concrete according to the following formula 1-4: (1), (2), (3), (4), In the formula, The splitting tensile strength of the concrete is expressed in MPa; the volume ratio of the rubber particles in the aggregate is calculated, 、 Is the particle size coefficient of rubber particles in the aggregate; Is the maximum particle size coefficient of rubber particles in the aggregate; the unit is mm, which is the maximum particle diameter of rubber particles in the aggregate; the minimum particle size of rubber particles in aggregate is in mm.
  2. 2. The method for predicting the split tensile strength of concrete according to claim 1, wherein the following is performed 1-25%.
  3. 3. The method for predicting the split tensile strength of concrete according to claim 1, wherein the following relation is satisfied: > ≥4.75mm。
  4. 4. The method for predicting the splitting tensile strength of concrete according to claim 1, wherein in the step S1, the inorganic aggregate comprises at least one of a first inorganic aggregate and a second inorganic aggregate, the particle size of the first inorganic aggregate is 4.75-9.6mm, and the particle size of the second inorganic aggregate is 9.6-19mm.
  5. 5. The method for predicting the split tensile strength of concrete according to claim 1, wherein in the step S1, the rubber particles include at least one of a first rubber particle having a particle diameter of 4.75 to 9.6mm, a second rubber particle having a particle diameter of 9.6 to 19mm, and a third rubber particle having a particle diameter of 4.75 to 19mm.
  6. 6. The method for predicting the splitting tensile strength of concrete according to claim 1, wherein in the step S1, the method for preparing the concrete comprises the steps of preparing materials according to a raw material formula of the concrete, and mixing, casting and curing the materials to obtain the concrete.
  7. 7. The method for predicting the splitting tensile strength of concrete according to claim 6, wherein the raw material formula of the concrete comprises, by weight, 500-700 parts of a gel material, 500-1500 parts of aggregate, 1-10 parts of a water reducer and 100-300 parts of water.
  8. 8. The method of predicting the split tensile strength of concrete of claim 7, comprising at least one of the following I-IV: I. The volume ratio of rubber particles in the aggregate is 1-25%; II. The gel material comprises cement, the cement comprising portland cement; III, the water reducer comprises a polycarboxylic acid water reducer; and IV, the inorganic aggregate comprises at least one of natural crushed stone and natural river sand.
  9. 9. The method for predicting the split tensile strength of concrete of claim 7, wherein said inorganic aggregate comprises a first inorganic aggregate and a second inorganic aggregate, said first inorganic aggregate being 195-420 parts by weight and said second aggregate being 510-680 parts by weight.
  10. 10. The method of predicting the split tensile strength of concrete according to claim 7, wherein the rubber particles include at least one of a first rubber particle, a second rubber particle, and a third rubber particle, the first rubber particle being 22 to 90 parts by weight, the second rubber being 22 to 90 parts by weight, and the third rubber particle being 22 to 90 parts by weight.

Description

Prediction method for splitting tensile strength of concrete Technical Field The invention belongs to the field of concrete, and particularly relates to a method for predicting splitting tensile strength of concrete. Background In recent years, more and more research has been focused on the incorporation of rubber particles formed by grinding junked tires into concrete to partially replace natural aggregate to prepare rubber concrete (Rubberized Concrete, RC). Experiments prove that the addition of the rubber particles is beneficial to improving the toughness performance of the concrete, improving the impact energy consumption capability and crack extension control capability of the concrete, and is particularly suitable for structural members needing certain ductility and deformation capability. However, because different types of natural aggregate and rubber particles are heterogeneous in concrete and are affected by different factors, the impact of natural aggregate and rubber particles on the mechanical properties of concrete is generally difficult to quantify. The splitting tensile strength is one of key indexes for evaluating the mechanical properties of concrete, reflects the capability of the material for resisting transverse tensile stress, and has important engineering significance in the fields of structural design, safety evaluation, quality control and the like. Traditional split tensile strength acquisition relies primarily on direct physical testing, namely split tensile testing (e.g., brazil disc testing). Although the method is a reference test means, the inherent limitations of complicated test piece preparation, destructive test process, long time consumption, high cost, difficulty in being applied to in-service structure or large-scale sample rapid screening and the like exist. To overcome the shortcomings of direct testing, researchers have developed a variety of indirect prediction methods. The prior art is based mainly on predictions of theoretical or semi-theoretical empirical formulas, for example estimated using statistical relations between uniaxial compressive strength and split tensile strength. However, such methods are usually based on idealized assumptions about homogeneity and isotropy of the material, and the parameters of the empirical formula are highly dependent on the specific material type and curing conditions, so that the universality is poor, and the prediction accuracy is often difficult to meet the high-accuracy engineering requirements. Moreover, the influences related to the particle sizes, the rubber substitution rates and the interface performances of different rubber particles are not taken into consideration generally, the material components, the microstructures, the macroscopic physical characteristics and the like cannot be fully excavated and fused, the adaptability to the working conditions and the material variation in the complex formula design is limited, and the model generalization capability is required to be improved. In view of the foregoing, it is highly desirable to propose a prediction method capable of comprehensively considering the particle size interval, substitution rate and interfacial property of rubber particles, so as to improve the scientificity and engineering applicability of prediction, and simultaneously provide theoretical support for the optimal design of the mixing ratio and the structural application of rubber concrete. Disclosure of Invention Aiming at the problems that the model for predicting the splitting tensile strength of the concrete containing the rubber particles is not wide in adaptability and influences caused by different rubber particle sizes and substitution rate intervals are not considered, the invention provides a method for predicting the splitting tensile strength of the concrete. In order to achieve the above purpose, the method specifically comprises the following technical scheme: the invention provides a method for predicting splitting tensile strength of concrete, which comprises the following steps: S1, preparing concrete, wherein the raw materials of the concrete comprise gel materials and aggregates, the aggregates comprise rubber particles and inorganic aggregates, and the volume ratio of the rubber particles in the aggregates is obtained Maximum particle diameter of rubber particles in the aggregateMinimum particle size of rubber particles in the aggregate; S2, calculating and determining the splitting tensile strength f st of the concrete according to the following formula 1-4: (1), (2), (3), (4), In the formula, The splitting tensile strength of the concrete is expressed in MPa; the volume ratio of the rubber particles in the aggregate is calculated, 、Is the particle size coefficient of rubber particles in the aggregate; Is the maximum particle size coefficient of rubber particles in the aggregate; the unit is mm, which is the maximum particle diameter of rubber particles in the aggregate; t