Automatic removing and sampling method for large-diameter aggregate of concrete for rheology

Abstract

The invention provides an automatic removing and sampling method for large-diameter aggregate of concrete for rheology. Common fresh concrete is conveyed into a screen drum by a guide chute through self-flow, a square-holed screen is arranged on the periphery of the surface of the screen drum, the drum has forward rotation and reverse rotation functions, tape helix guide blades are welded in the drum, the screen drum rotates forward at a fixed rate to remove coarse aggregate automatically, and a mixture of residual concrete on sieve falls under dead weight into an accommodating test capacity drum which is used for detecting rheological property characterization parameters of the mixture. Meanwhile, during each screening, an ultrasonic level indicator detects the height of the to-be-tested concrete mixture in the accommodating test capacity drum in real time, so that the screen drum is controlled and regulated to rotate reversely for unloading on the basis of automatic feedback. With adoption of the method, the coarse aggregate can be removed automatically through rolling, materials are prevented from getting stuck and blocking screen holes in screening processes, the mixture of the residue concrete on sieve is sampled uniformly, and test stability, accuracy and reproducibility of rheological characterization parameters of the concrete are guaranteed.

Description

technical field [0001] The invention relates to a method for automatically removing and sampling large-size aggregates of rheological concrete, in particular to a screen drum with forward and reverse functions, which realizes the automatic removal of coarse aggregates containing over-specified particle sizes in fresh concrete after flow Uniform sampling method for variable test samples. Background technique [0002] The purpose of the rheological performance test of fresh concrete is to measure the yield stress, plastic viscosity and thixotropy of the representative sample of fresh concrete through the measurement of cross-shaft shearing instrument, so as to provide an important guarantee for the normal pouring of fresh concrete on the construction site . However, in the rheological performance test of concrete at the construction site, the rheological parameters are very sensitive to the particle size of the original concrete coarse aggregate. In view of the size limit of ...

AI Technical Summary

Problems solved by technology

Although these screens have the function of removing the specified large aggregate, they lack the technology of automatic aggregate removal and reliable removal of aggregate-wrapped slurry, which cannot satisfy the automatic stabilization of test samples containing coarse aggregate concrete with over-specified particle size on the construction site. Elimination requirements

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