Influence and Mechanism of Curing Methods on Mechanical …
The mechanical properties of ultra-high performance concrete (UHPC) made of manufactured sand (MS) under four curing methods (steam, standard, sprinkler and saturated Ca(OH) 2) were investigated via compressive, flexural and uniaxial tensile tests, and the bond strength of steel fiber and manufactured sand UHPC (MSUHPC) matrix.Based on the analysis …
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Mechanical properties and hydration mechanism of nano-silica …
Additionally, the SiO₂ primarily originates from the fine sand in the waste concrete. Chemical composition tests were conducted on both RC and OPC, as shown in Table 1 . From Tables 1 and it can be seen that the chemical composition of RC is similar to that of OPC, with the main oxides being CaO, SiO₂, Al₂O₃, and Fe₂O₃.
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DEM modeling direct shearing behavior of sand considering anti …
Introduction. Sand is a typical granular material.Sand's particle shape, size and other properties affect the mechanical properties of it 1 – 3.At present, there are many test methods to study the mechanical properties of sand, and the direct shear test is a classical and simple method to study the mechanical properties of sand 4 – 8.Nowadays, a large number of …
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Study on shear resistance and crack resistance and toughening mechanism
The cement contents were 0, 3, 5 and 7% (by weight of the dry sand), silica fume contents were 0 and 0.5% (by weight of the dry sand) and PET fiber contents were 0, 0.65, 0.75 and 0.85% (by weight of the dry sand) with lengths of 8, 10 and 12 mm. Various properties including stress–strain curves, deformation characteristics and failure ...
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Analysis of Early-Age Hydration Behavior and Micro-Mechanism …
2.1. Materials. The materials used in this study include coral sand, OPC 52.5 cement supplied by Zhucheng Yangchun Cement Co., Ltd. (Weifang, China), and standard sand supplied by China ISO Sand Co., Ltd. (Xiamen, China) The maximum particle size of coral sand was controlled at 2 mm by sieving to ensure uniformity of the slurry to better explore the early …
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Influence and Mechanism of the Excavation Width on Excavation
This study investigated the influence and mechanism of the excavation width on excavation deformations in Shanghai soft clay. Based on three excavations that had different final excavation depths, dissimilar retaining structures and diverse geological conditions, 40 sets of two-dimensional numerical models with different excavation widths were employed to analyze …
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Mechanism of Sand Cementation with an Efficient Method of …
Mechanism of Sand Cementation with an Efficient Method of Microbial-Induced Calcite Precipitation. ... Co., Ltd., Shanghai, China), which was usually applied to compare different growth characteristics of the bacteria, recorded as OD600. ... where S is the compressive strength and x is the percentage of calcite content. Open in a separate window.
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The Influence and Mechanism of Curing Methods and Curing Age …
Compared with traditional sand, it is found that the ultimate bending load and deflection of YRS-ECC are 5.7% and 9.4% higher than those of traditional sand ECC, respectively, and its ultimate ...
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Experimental study on the mechanical properties and …
There are three primary methods for implementing MICP, including the mixing method, soaking method, and grouting method. The mixing method [6], [7], [8] involves creating a homogenous aggregate bacterial solution and cementation solution, and then mixing them together in specific proportions to facilitate curing and sample solidification. The soaking …
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(PDF) Effects of rock types and crushing mechanism on the 3D
This study aims to investigate the effect of rock types, i.e., granite, conglomerate rock, limestone, and crushing mechanism, i.e., Vertical Shaft Impact (VSI) crusher, Horizontal Shaft Impact ...
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Substantial increase in China s manufactured sand supply …
Here we present a material flow analysis of sand from 1995 to 2020 that shows China's overall sand supply surged by approximately 400% over the study period, yet the proportion of natural sand...
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Research on frost resistance of desert sand
In order to mitigate the harm to the ecological environment caused by the overexploitation of river sand and machine-made sand and the continuation of desertification, this study carried out a freeze-thaw cycling test on concrete with desert sand admixture as a variable and comprehensively analyzed and evaluated the frost resistance of concrete with different …
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Harnessing Limestone powder to enhance the thermal crack …
Manufactured sand concrete (MSC) has increasingly applied in engineering. However, how to enhance the thermal crack resistance of MSC has not clearly studied yet, which limits the wide applications of manufactured sand in engineering. We have adopted the method of mixing limestone powder (LP) to make MSC with four mass fractions (wt.%) of 5%, 10%, 15%, …
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Effects of rock types and crushing mechanism on the 3D
manufactured sand and evaluating the effects of rock types and crushing mechanisms on the morphological characteristics are important issues for the production and application of manufactured sand. The study of sand morphology originated from two dimensions and gradually developed into three dimensions (Zhu et al., 2014).
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Research on the influence of machine-made sand gradation and …
Research shows that with the increase of the cumulative screening rate and fineness modulus of machine-made sand with different gradations, the fluidity of the mortar increases …
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(PDF) Optimization of All-Desert Sand Concrete Aggregate …
the coarser-grained mechanism sand into the desert sand in a certain proportion [7] ... proportion of C100 concrete, and successfully determined the proportion of C100 ... Shanghai Chenqi Chemical ...
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Analysis of Mechanism of Sand Gushing and Sudden Sinking of …
The plane size of the open caissons of the Shanghai-Suzhou-Nantong Yangtze River ... in this test is 63.0 cm, which takes 1628 s, and the average sinking speed is 2.3 cm/min. According to a similar proportion of 1:69, the sinking rate of the prototype ... the mechanism of sand gushing and sudden sinking for a typical ultra-large deep-water open ...
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Study on the Durability of Manufactured Sand Concrete with …
that when the sand ratio is between 0.38 and 0.44, the mechanism of sand best workability and durability of the concrete strength, the best value for the mechanism of sand concrete, sand ratio range within the scope of the young stage of mecha- ... Keywords Mix proportion parameters ·Manufactured sand concrete ...
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Exploration of the Composition and Microstructure of the Historic
This article aims to clarify the composition and properties of early modern Chinese concrete to improve understanding for conservation purposes. Commencing with an …
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Investigation of Engineering Properties of Cement‐Stabilized …
In this paper, the basic engineering characteristics, bearing capacity, and deformational behavior of calcareous sand were studied by carrying out a series of tests on …
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Optimizing mix design of concrete with manufactured sand for low
Previous research has highlighted the promise of machine learning technologies in optimizing concrete mix proportions to minimize embodied carbon. However, nearly all the …
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Suspension mechanism and application of sand-suspended …
Until now, some studies have reported the grouting for fire prevention in coalmines, and the conventional sand injection are mainly applied [6], [7], [8].The ratio of water to sand must reach 7:1 to 15:1 if the fly ash or sand with water is simply injected to ensure that the sand would not subside [9], [10], [11].The technology, however, tends to waste large amounts of water, …
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Effect of Stone Powder Content on Mechanical Properties of …
ting tensile strength, and modulus of elasticity of mechanism sand concrete was studied with mechanism sand in a region of Guangxi. The modulus of elasticity of the concrete with stone powder was predicted by a three-phase composite model. ... proportion of stone powder content aecting the strength was higher than that of the water-binder ratio ...
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Study on the Preparation of Full Solid Waste-Based Concrete …
2.1 Raw Material Analysis. The test sand consisted of continuously graded mechanism sand ranging from 0–10 mm and continuously graded iron tailing sand ranging from 0–5 mm, while the coarse aggregate comprised continuously graded from 5–25 mm.
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Investigation of alternative mechanisms of aquifer-system …
analysed the land subsidence in Shanghai based on Cosserat mechanics, as shown in Fig. 3. The result indicated the model based on Cosserat mechanics simulated the measured data well. 3.4 Internal erosion of fine particles in sand. An alternative mechanism causing subsidence in Shanghai is proposed here. Large quantities of silt and clay particles
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Experimental study on fiber-reinforced cement tailings sand …
Selecting tailings sand with an appropriate particle size range can give grouting material excellent fluidity and strength [42]. Subsequently, ITS was sieved using an impact-type standard shaking apparatus to obtain particle sizes ≤0.15 mm, replacing a proportion of the OPC in the grouting material.
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Effects of different sand fixation plantations on soil properties in
At the same soil depth, the volume percentage content of soil clay, silt, and very fine sand was: U. pumila > P. sylvestris var. mongolica > P. simonii > bare sandy land, while the volume ...
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Substantial increase in China's manufactured sand …
Here we present a material flow analysis of sand from 1995 to 2020 that shows China's overall sand supply surged by approximately 400% over …
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Investigation of the long-term tunnel settlement mechanisms of the
When exploring the mechanism of tunnel leakage, the research method that th shield tunnel lining is equivalent to a homogeneous permeable body is used by mos scholars [4,18,20].
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Degradation mechanisms and lifespan prediction of desert sand …
Dry-mixed mortar is a pre-blended construction material consisting of cementitious materials, fine aggregates, and additives in specific proportions [1].It finds extensive applications in various construction engineering contexts, including wall block masonry, paver block installation, and tile adhesion [1], [2], [3].This material is pre-packaged at manufacturing …
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