Steel shell immersed tube self-compacting concrete mix proportion design method and concrete

Abstract

The invention discloses a steel shell immersed tube self-compacting concrete mix proportion design method and concrete. The mix proportion design method comprises the steps: preparing materials for the concrete; calculating a preliminary mix proportion by adopting a fixed sandstone volume content calculation method; according to an orthogonal test design method principle, performing influence factor analysis on the preliminary mix proportion to obtain a preferable mix proportion; performing test verification on the preferable mix proportion to obtain an optimal mix proportion; and carrying outa process test on the optimal mix proportion to determine that the optimal mix proportion meets the production requirements. The mix proportion design method disclosed by the invention is based on the combination of the fixed sandstone volume content calculation method and the factor design analysis method; according to the method, the optimal mix proportion meeting the requirement for pouring the high-self-compaction concrete into small compartments of a steel shell immersed tube is designed, the designed concrete can be compacted and formed only through the gravity effect of the concrete without additional mechanical vibration, segregation is avoided in the flowing filling process, and thus it is guaranteed that the concrete makes close contact with the steel shell, and cooperative stress is achieved.

Description

technical field [0001] The invention relates to the technical field of building materials, in particular to a mixing ratio design method of steel shell immersed tube self-compacting concrete and the concrete. Background technique [0002] The "sandwich" steel-shell concrete immersed tube structure has only been applied and developed in Japanese immersed tube tunnels in the past two decades, but the public technical information is very limited, and a large number of core technologies and process details are still kept secret and undisclosed. The reinforced concrete structure is used in the immersed tube tunnels that have been built or are under construction in my country, and the steel shell concrete immersed tube has not been applied yet. [0003] The Shenzhong Channel is a strategic cross-river channel connecting the two sides of the Pearl River. It is a four-in-one cluster project integrating ultra-wide subsea tunnels, super-large span bridges, deep-water artificial island...

AI Technical Summary

Problems solved by technology

During the construction process, due to the large number of immersed tube compartments in the steel shell, there are more than 2,000 compartments in a single steel shell, and each compartment is independent of each other, and the self-compacting concrete has high sensitivity and large performance fluctuations, which are mainly affected by raw materials and other factors. If the working performance of self-compacting concrete is affected and the design index cannot be reached, pouring concrete in a closed steel shell is a concealed construction, which is prone to defects such as non-compacting and air bubbles, and it is difficult to accurately detect and deal with it

At present, there is no efficient and accurate detection method in China. Japan mainly adopts process control. It believes that process control meets the requirements, and it is difficult to detect afterwards.

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