Experimental Study On Evaluation Methodology For Compressive Strength And Stress-strain Curves Of Concrete Hollow Blocks

In recent years, with the strong promotion of China’s economic developmentand urbanization, the national construction industry has achieved vigorousdevelopment. As an important part of modern masonry structure, load-bearingconcrete block has an unprecedented period of development opportunity.However, the existing standards of the test method, the evaluation criteria andthe project acceptance criteria are lagging behind the actual engineeringrequirements of building structure. How to achieve the transformation of the testmethods, the evaluation criteria and the basic fundamental research on concreteblock for unreinforced masonry structure or traditional reinforced masonrystructure to modern reinforced masonry structure, that is a critical issue forhealthy development of block industry.Through the analysis of the strength test method, the evaluation criteria andthe stress-strain curve of concrete hollow block, this article mainly discusses thefollowing four aspects:(1) Through the compressive strength test on concrete hollow block ofdifferent manufacturers, different strength grade and different specifications indifferent capping method, this article will make a detailed analysis oninfluencing factors of concrete block’s testing compressive strength, and proposea control index for parallelism of block’s pressure-bearing surface. Meanwhile,this article will analyze the feasibility of cutting method for the qualityinspection of nonstandard block.(2) Combined with the concrete block’s compressive strength data of thistest and others, this article will analyze the distribution model of concrete block’scompressive strength, the quality stability between different batches and thedistribution model of different strength grade block’s unqualified rate, and getthe unique distribution of block’s strength quality and the estimated value ofsome important parameters.(3) Based on the theory of Sampling inspection method, and combinedwith the feature of block’s strength quality distribution, this article will analyzethe reasonable value of the producer’s risk α, the consumer’s risk β, theacceptable qualityp0and the limit qualityp1, and then build a block’s strengthevaluation criteria as well as the corresponding sampling inspection rules, andfinally conduct a simulation analysis for the sampling inspection rules with themethod of Monte Carlo Simulation. (4) Through the compressive strength test on concrete hollow block ofdifferent strength grade and different specifications by electric-hydraulic servingcompression machine, this article will analyze the value rule of the block’sinitial-crack capability, elasticity modulus, Poisson’s ratio and peak strain, andthen fit the stress-strain curve for the concrete block under uniaxial compression.