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Ahmad, A. et al. Prediction of geopolymer concrete compressive strength using novel machine learning algorithms. Polymers 13(19), 3389 ... Rock Mech. Rock Eng. 55(4), 1887–1906.
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The results obtained from this study indicated that knowing any physical or mechanical property of rock used for producing aggregate could be used to estimate the …
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5.2 Method C, uniaxial compressive strength of rock is used in many design formulas and is sometimes used as an index property to select the appropriate excavation technique. Deformation and strength of rock are known to be functions of confining pressure. Method A, triaxial compression test, is commonly used to simulate the stress conditions under which …
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Based on the findings of this study, it is recommended that the size effect and the reduction of aggregate size on dam strength be taken into account in the design of RFC dams. 1. Introduction. Rock-filled concrete …
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The standard k-nearest neighbors (k-NN) with cross-validation were utilized to develop compressive strength prediction models for some concretes and rocks by considering …
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In the last five decades, there have been a multitude of semi-empirical relations for the estimation of unconfined compressive strength using measurements from non-destructive testing methods. First, the study of Rzhevsky and Novick [1] was proposed in1971 to estimate the compressive strength for dolomites and limestones using n e as predictor.
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They also tested original Ancient Roman hydraulic concrete that was dated to the 1st century as having a compressive strength to 1160 psi. The Ancient Roman sample has had over 2000 years to hydrate. ... Concrete is an artificial rock that has become an essential building material in the modern world. The technology was first developed by the ...
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The rock uniaxial compressive strength (UCS) is the basic parameter for support designs in underground engineering. In particular, the rock UCS should be obtained rapidly for underground engineering with complex …
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The compressive strength of rock (RCS) represents the maximum compressive stress that rock can withstand before failure under external loading; it is an indispensable parameter in rock mass stability analysis, tunnel construction, mining excavation, and the design and support of hydroelectric power stations (Hoek and Brown 1980; Hawkins 1998; Moussas …
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The standard k-NN was utilized to develop compressive strength prediction models for some concretes and rocks by considering indirect parameters such as physical and mechanical parameters. To verify and validate the standard k- NN models, prediction results of models reported in the literature were compared using six datasets via the cross ...
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A compressive testing machine, having an increasing rate of load of 140 kg/cm 2 per minute, was used in order to calculate the concrete strength by the division of the value of the load at the moment of failure over the area of specimen. The concrete strength was calculated via BS EN (2009) standard.
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For Type III porous concrete, the R 2 value suggests that 82.07 % of the variability in compressive strength can be attributed to variation in density, which is close to the value obtained for Type I porous concrete. Although the data points are more dispersed compared to Types I and II, they still show a clear relationship between the variables.
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A couple of pioneering studies investigated the long-term strength of metals and concrete materials based on a relationship between the secondary creep strain rate and the time-to-failure (Monkman 1956; ... D2938-Standard test method for unconfined compressive strength of intact rock core specimens, Current edition approved June 15, 1995 ...
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The Compressive Strength Calculator is a tool that determines the compressive strength of a material, which is the capacity of the material to withstand compressive forces without failing. It is a vital calculation in engineering, construction, and material science, used to evaluate materials like concrete, steel, and ceramics.
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The results indicate that the order of the triaxial strength and deformation resistance of rock–concrete combined bodies is G-C50, S-C50, G-C30, and S-C30, from large …
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In the study of the effect of aggregate size on the compressive strength of concrete, Wu et al. prepared three kinds of aggregate size ranges of concrete cubic specimens; the aggregate size ranges were 5–10 mm, 10–16 mm, 16–20 mm, and the uniaxial compression test of the specimen showed that the compressive strength of concrete increased ...
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In particular, the Uniaxial Compressive Strength is re-calculated as: σ c = σ UCS / (0.88 + 0.222*(D/L) ) Where σ c is the corrected uniaxial compressive strength. Rock characterization and typical range of UCS based on rock types . Based on their Uniaxial Compressive Strength, rocks can be characterized from very weak to very strong as ...
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2.2.3 Compressive strength and strain test. The strength of any concrete structure is measured by its resistance to external loads and conditions. To calculate this resistance, testing samples are taken, and the compressive strength of each sample is determined using a compressive strength testing machine, as shown in Fig. 4A, B. This calculation involves …
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The advantage of a better bond between the sand and the binder results in improved concrete strength. For concrete with strength grades above C30, including high-strength and high-performance concrete such as C60, the compressive strength is higher when prepared with graded sand compared to river sand concrete (ensuring that the rock-powder ...
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For the purpose of structural design, concrete is classified into several strength classes based on the so-called characteristic compressive strength f ck in most of European standards (e.g. EN 1992 [3] and NF EN 206-1 [4]) or on the specified compressive strength f c ' in the American standard (ACI-318 [5]).Hereafter, both f ck and f c ' are referred as the …
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2.1 Specimen Preparation. In this work, the two most common types of rock in China are first selected, namely sandstone and granite, denoted as S and G. Moreover, two strength grades of concrete are prepared according to Table 1, denoted as C30 and C50.For concrete, the raw materials are as follows: (1) cementing materials are CEM I 42.5R Portland …
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Using gabbro rocks concrete higher compressive strength and its properties of concrete. Keywords: Coarse Aggregate, Compressive strength, fine aggregate, gabbro concrete. I. INTRODUCTION Nowadays, as the field of civil engineering have become so innovative hence providing economic constructions and good strength. Use of Igneous rock aggregates ...
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This study examines the influence of the physico-mechanical properties of the intact rock of aggregate materials on the strength performance of a concrete. For this aim, nine different aggregate types were produced from nine different intact rocks, and they were used in the production of nine different concretes. The physical and mechanical properties of the …
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In order to establish an optimal model for reasonably predicting the uniaxial compressive strength (UCS) of rocks, a method based on feature optimization and SSA-XGBoost was proposed. Firstly, the UCS predictor system of rocks, considering petrographic and physical parameters, was determined based on the systematic discussion of the factors affecting the …
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This paper presents a machine learning-based approach to estimating the compressive strength and elastic modulus of rocks. A hybrid model, GWO-ELM, was built based on an extreme learning machine network optimized by the grey wolf algorithm. The proposed model was carried out on 101 experimental datasets, and four commonly used models were …
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Uniaxial compressive strength (UCS) and modulus of elasticity (Es) are two basic parameters in geotechnical engineering. Determination of UCS and Es requires considerable time and money to collect and prepare suitable specimens and laboratory tests. The aim of this study was to evaluate the methods of multilayer perceptron artificial neural network (MLP-ANN), …
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Typical values for these parameters are obtained by curve-fitting the uniaxial compressive strength f c, uniaxial tensile strength f t, and from the biaxial and triaxial data (for instance, a typical biaxial compressive strength of concrete is 16% …
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The principal tensile stress of the compressive stress and tensile stress loads on certain microelements inside the concrete first exceeds the tensile strength of the concrete …
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Rock-filled concrete (RFC) represents a novel advancement in mass concrete construction, providing significant benefits such as decreased cement consumption, increased compressive strength, and reduced shrinkage …
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By conducting numerical simulations based on unconfined compression tests and employing the mineral crystal GBM approach, the patterns in rock compressive strength …
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A large number of joints and fissures are prevalent in the rock mass, which has an important influence on the mechanical properties of the rock mass. To study the failure mechanical characteristics of Y-cracked rocks, the paper analyzes the influence of different angles of prefabricated Y-cracked rocks on the mechanical strength characteristics of the …
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The impact of rock-filled ratio on compressive strength, porosity, and electrical resistivity is also evident in Fig. 3. At curing age of 28 days, compared to the control group RFC0, the compressive strength increased by 1.09 %, 7.42 %, and 18.78 % for rockfill ratios of 30 %, 35 %, and 40 %, respectively.
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Building materials, especially low-quality concrete, are believed to be a source of building collapses. One way to determine the quality of concrete is by testing its compressive strength, also known as Concrete Compressive Strength. The compressive strength of concrete depends on the components used in the mixing process.
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To find out how strong and load-bearing concrete is, Compressive Strength Test is the way to go. Get the quote 24*7 and call us. ... engineers and architects accurately measure the compressive strength of materials such as rocks and …
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uniaxial compressive strength σci of the intact rock pieces, value of the Hoek-Brown constant mi for these intact rock pieces, and value of the Geological Strength Index GSI for the rock mass.
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As a results, depending on the type of the parent rock, compressive strength differs over an expansive range. Moreover, according to Fig. 7, concrete specimens containing aggregates prepared from parent rocks with higher compressive strength, revealed higher compressive strength compared with other concrete specimens. For this reason, concrete ...
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