Precast News From China
Drilled pile is widely used in foundation engineering in coastal areas.
Due to its concealed construction process, it is difficult to visually monitor the entire construction process.
Various quality problems are prone to occur during the concrete construction of drilled pile, such as steel cage floating, rapid concrete setting, segregation, and pile breakage.
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With the development of human civilization and engineering construction technology, concrete, as the most important material in construction projects, is experiencing a significant increase in production.
The carbon emissions generated by the construction industry account for 8% of the total global carbon emissions, so the construction industry must be committed to sustainable development and vigorously develop low-carbon construction technology innovation.
At present, the demand for low-carbon building materials is increasing day by day, and low-carbon concrete has become a popular term in the industry.
How to reduce the carbon emissions of concrete production through technological means is the main problem currently faced.
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As a key component of modern transportation systems, highways have increasingly strict requirements for construction quality, especially in key structures such as bridges and pavements.
The performance of concrete materials directly affects the safety and stability of the project.
Traditional concrete is prone to cracking, peeling, and other problems when exposed to harsh environments, thereby reducing the service life of the structure.
With high-performance concrete gradually becoming a research hotspot, this material has become an ideal choice for dealing with complex environments due to its high compressive strength, good durability, and low permeability.
However, optimizing the mix proportion of high-performance concrete, selecting suitable raw materials, and controlling the construction process remain the core challenges in improving its performance.
Nevertheless, the academic and engineering communities have conducted extensive research and proposed many effective optimization design methods and improved construction techniques.
However, in practical applications, high-performance concrete still faces technical challenges, especially in material selection and cost control.
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3 Temperature measurement during concrete curing shall comply with the following regulations:.
Load cracks, also known as stress cracks, are structural cracks that occur under external loads.
This type of crack has a strong regularity, and accurate conclusions can generally be drawn through calculation and analysis.
A typical simply supported beam experiences stress cracks, with a normal section bending crack at the mid span, perpendicular to the beam axis and larger at the bottom and smaller at the top; The end is a diagonal section shear crack, starting from the support and pointing towards the concentrated load at the top of the beam.
Cracks in steel-concrete columns under axial compressive loads are distributed longitudinally along the column axis, with slightly denser cracks in the middle.
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Currently, the construction industry is accelerating its transition towards green and industrial development, with concrete PC components (precast concrete components) becoming a key driving force.
The traditional on-site pouring mode is greatly constrained by natural factors, has a lot of construction waste, and is difficult to control quality.
On the other hand, PC components are precast in factories through standardized processes, covering types such as laminated floor slabs, precast exterior walls, stairs, beams and columns, just like standardized building parts, solving industry pain points.
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Quality of cement substrate: The type and proportion directly determine the compressive strength and chemical resistance of concrete.
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Plastic shrinkage often occurs in the semi fluid or plastic stage of concrete, which is caused by various factors such as settlement motion, capillary tension, early chemical shrinkage, and self shrinkage, resulting in changes in concrete volume.
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However, although polycarboxylate based admixtures have solved the requirements for high-rise pumping and durability of ready mixed concrete, they are highly sensitive to fluctuations in concrete raw materials and environmental conditions, leading to various problems during the construction of ready mixed concrete.
If there is a phenomenon of rebound in the slump of ready mixed concrete, especially in winter, this phenomenon is more common, and the ready mixed concrete mixing plant also solves it vaguely every time.
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