Hydraulic Reinforced Concrete Structures | Key Summary of the Whole Book (6) Chapter 5 Calculation of Bearing Capacity of Reinforced

For the convenience of template production, compression members generally adopt square or rectangular cross-sections.

When using a rectangular section for eccentrically compressed components, the long side of the section is arranged in the direction of the bending moment, and the ratio of the long side to the short side is generally 1.

Steel Chamfer

5 to 2.

5.

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The Effect of Grading Efficiency of Cementitious Materials on Concrete Strength

In the past decade, experts and scholars have clearly pointed out that the strength and durability of concrete mainly depend on the characteristics of the cementitious matrix and the bonding properties between the cementitious matrix and aggregates.

Elephant Foot Ferrule

The bonding properties between the matrix of the cementitious system and the aggregate depend on the characteristics of the matrix of the cementitious system.

Therefore, this article verifies whether the optimal stacking state of various materials in the cementitious system has a beneficial effect on the formation of concrete structures, and ultimately aims to broaden the design ideas of mix proportions and improve the economic benefits of concrete production enterprises.

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The influence of mechanism sand mixed with stone powder on the performance of C50 bridge concrete

Concrete, as the most widely used building material, occupies a core position in China’s infrastructure field.

In 2021, China’s concrete production reached a peak of 3.

3 billion cubic meters, of which fine aggregates accounted for over one-third.

However, as a traditional fine aggregate, natural river sand is a non renewable resource, and its mining not only incurs high costs, but also faces the problem of increasingly depleted resources.

Erection Anchor

In this context, mechanism sand has become an ideal alternative material due to its abundant resources, simple preparation process, and economic advantages.

However, its inherent problems such as strong particle angularity, poor gradation continuity, and high stone powder content limit its application in high-grade concrete structures such as bridges.

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Laboratory under the “involution” of the concrete industry

Nowadays, the concept of “involution” has evolved into a synonym for vicious competition and internal friction in development, and is showing an increasingly fierce trend in the concrete production industry.

Concrete production enterprises are deeply trapped in the dilemma of internal competition, and the vicious cycle of low price competition is squeezing their profit margins.

Some enterprises even use unqualified raw materials to reduce costs, causing quality hazards.

Pfeifer VS Box

The concrete industry faces severe homogenization competition, insufficient innovation drive, and is trapped in a closed loop of “low-level repetitive construction – declining profits – reduced technology investment”.

The key to cracking the industry’s internal competition lies in getting rid of low-level competition traps.

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The Influence and Suggestions of Air Content on Concrete in Water Reducing Agent Testing

Figure 1 shows the scatter plot of the relationship between gas content and water reduction rate for 46 samples.

From the graph, it can be seen that the water reduction rate of the water reducer is roughly positively correlated with the air content, that is, as the air content increases, the water reduction rate of the water reducer will also increase.

Not only that, introducing air into concrete can also increase the cohesion of concrete and the lubrication effect between materials, improve the segregation and bleeding of concrete, and enhance the workability of fresh concrete [1].

Edge Lift Anchor

Meanwhile, appropriate air entrainment in concrete can also improve its frost resistance, significantly enhancing its impermeability, resistance to chloride ion penetration, and carbonation resistance [2].

But if the air content is too high, it can also lead to too many holes in the concrete, making it less dense and reducing its strength.

Therefore, the current standard GB8076-2008 “Concrete Admixtures” [3] stipulates that the upper limit of the air content of high-performance water reducing agents is 6%.

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