The principle of workability refers to the basic principle of uniform quality and compact formation of fresh concrete at each stage.
Its specific connotations include fluidity, cohesion, water retention, etc.
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The principle of workability refers to the basic principle of uniform quality and compact formation of fresh concrete at each stage.
Its specific connotations include fluidity, cohesion, water retention, etc.
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Using 52.
5 grade ordinary Portland cement with a specific surface area of 3148m2/kg; 5mm to 25mm continuous graded crushed stone, with an apparent density of 2660kg/m3 and a fineness modulus of 2.
8 for ordinary river sand, with an apparent density of 2640kg/m3; Ordinary tap water; High performance polycarboxylate superplasticizer ME-1, with a water reduction rate of 25% and a solid content of 27%.
The dosage is adjusted according to the state of the concrete, so that the slump of the concrete is between 140mm and 160mm.
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At the age of forty, encountering a downturn in the concrete industry is like holding a broken umbrella in a storm – both resisting the impact of the industry downturn and stabilizing the burden on the family.
This dilemma is essentially a triple combination of the downward trend of the concrete industry, age pressure, and family responsibilities, like a “checkpoint” sandwiched between family responsibilities and career difficulties.
When the industry downturn overlaps with the pressure of life stages, the helplessness of not daring to stop or retreat hides too much weight of reality behind it.
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In recent years, with the gradual shrinkage of mineral resources and the increasing efforts of national environmental inspections, concrete raw materials such as cement and sand have been in short supply, leading to a continuous rise in raw material prices.
This has also promoted the research and industrialization of industrial waste such as steel slag and tailings as raw materials in concrete.
The sources of industrial waste are complex, and using it in engineering projects without effective pest control and quality verification often poses significant quality risks and can easily cause significant economic losses.
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The excavation section of the trench should comply with the requirements of the construction organization design (plan).
The undisturbed foundation soil at the bottom of the trench shall not be disturbed.
During mechanical excavation, a 200-300mm soil layer shall be reserved at the bottom of the trench for manual excavation to the design elevation and leveling;.
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Misalignment: At the joint or crack of the concrete pavement, there are steps on both sides of the pavement, which can cause vehicles to jump when passing through, affecting driving comfort and safety.
This quality issue and phenomenon occur after a certain period of operation.
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Personnel entering the site for work must undergo on-site safety education and pass the assessment before proceeding with the work.
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On April 8th, the national cement market experienced small-scale fluctuations, with Bijie, Liupanshui, Dalian, and Harbin falling and Zunyi rising.
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According to British media reports on April 2nd, small cracks in concrete can almost self repair because bacteria can generate minerals inside the cracks.
Wide and diagonal cracks can reduce water leakage by up to 80%.
These findings suggest that the shape of concrete cracks plays a crucial role in the self-healing process, transforming a promising idea into a system that engineers can predict and utilize.
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(1) Temperature: The higher the temperature, the faster the condensation time.
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