A 3D printing concrete constructability test device and method

Abstract

The invention provides a 3D printed concrete constructability test device and method. The device consists of a bracket, a load container, a moulding die and a laser displacement detector. The upper part of the bracket is a support sleeve, the bottom is a base plate, and the support sleeve is fixedly connected to the base plate through support rods. The load container has an opening upper part anda sealed bottom, and passes through the support sleeve. The moulding die is used for making a to-be-tested mortar model. The laser displacement detector includes two laser displacement sensors and a display screen, a longitudinal laser sensor is fixedly installed on a side wall of the load container, a horizontal laser sensor is disposed on the base plate through a movable fixation apparatus, andthe display screen is connected to the two laser displacement sensors through a wire. The device and method provided by the invention can completely simulate the printing situation in the actual process, and achieve ultra-high reduction of deformation in the printing process, and can make a vertical deformation curve in the loading procedure visible directly, and by simulating the printing time interval of different layers, can study the influence of interlayer printing time interval on constructability, and provide reference for determining the vertical printing rate.

Description

technical field [0001] The invention belongs to the field of concrete performance testing, and in particular relates to a 3D printing concrete constructability testing device and method. Background technique [0002] Existing literature defines printability in 3D printed concrete as the ability of cement-based materials to pass smoothly through 3D printing systems. Printability is not just a pure property of the material, it is related to the extrudability, buildability and interlayer bond strength of the material. [0003] Extrudability: Freshly mixed cement-based materials pass through the extrusion port smoothly through pumping or screw extrusion, and the extruded strips of concrete are uniform and continuous without tearing or breaking. [0004] Buildability: The ability of fresh cement-based materials to maintain their own shape after being extruded and subjected to their own weight and the pressure of the upper covering layer. [0005] Interlayer bond strength: The a...

AI Technical Summary

Problems solved by technology

At present, there is a lack of accurate testing equipment for the construction of materials at home and abroad. Only a simple evaluation method is given for the deformation of materials. It is difficult to compare with the deformation in the printing process, and it is impossible to simulate the deformation value in the printing process. There are many accidental errors in the operation process. , the measured index fluctuates greatly

[0007] It can be seen that the existing technology cannot simulate the 3D printing process of concrete, and cannot simulate the denaturation value of concrete during the printing process, and there are many accidental errors in the operation process, and the fluctuation of the measured index is large, so the constructability of 3D printed concrete cannot be accurately tested.

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