Sandstone gravel C60 low-creep concrete for bridge engineering

Abstract

The invention belongs to the technical field of engineering materials, and particularly relates to sandstone gravel C60 low-creep concrete for bridge engineering. The technical key points are as follows: the concrete comprises the following components in percentage by mass: 11.37%-13.83% of Portland cement, 2.96%-3.79% of sintered superfine fly ash, 2.96%-3.79% of ground granulated blast furnace slag powder, 28.31%-28.69% of sand, 46.19%-46.81% of sandstone gravel, 5.5%-5.73% of water, 0.002%-0.013% of an internal curing agent and 0.016%-0.034% of a shrinkage type polycarboxylic acid high-performance water reducing agent. According to the invention, the purpose of reducing creep of the sandstone gravel C60 concrete is achieved by utilizing the super-superimposed effect among the components such as the fired fine fly ash and the ground granulated blast-furnace slag powder and utilizing the shrinkage-reducing and performance complementary effects of the internal curing agent and the shrinkage-reducing type polycarboxylic acid high-performance water reducing agent, and the application of the sandstone gravel in the bridge engineering low-creep concrete is realized.

Description

technical field [0001] The invention belongs to the technical field of engineering materials, and in particular relates to sandstone crushed stone C60 low-creep concrete for bridge engineering. Background technique [0002] Continuous rigid frame bridge is a commonly used structural system in the construction of long-span bridges. It has the advantages of simple construction operation, reasonable force, and low cost. However, it has been found in the long-term operation of bridges at home and abroad that continuous rigid Long-term deflection of the main span and cracking of the beam body exist in continuous rigid-frame bridges. There are many main reasons for the mid-span deflection and cracking of long-span continuous rigid frame bridges. The large creep of concrete itself is the primary factor leading to the long-term prestress loss of concrete bridges leading to deflection and cracking. [0003] Studies have shown that the lithology of coarse aggregate has a significant ...

AI Technical Summary

Problems solved by technology

However, due to the limitations of transportation conditions and regional concrete aggregate conditions, some bridge projects have the problem of limited lithological selectivity of crushed stones for concrete within a short distance.

For example, sandstone is the only choice for concrete gravel in the vicinity of some bridge projects (within 500 kilometers around). If limestone or other lithological gravel is forced to be used, high transportation costs will be required due to problems such as poor traffic during transportation. The extension of the construction period brought about further increased the construction cost of the project

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