Vibre anti-permeation cracking-resistant concrete

Abstract

The present invention relates to a fibre impervious crack-resisting concrete, and its ingredients and admixing quantities are: 1. general Portland cement; (2). medium sand; (3) stone; (4) water-reducing agent; (5) slag powder, internal admixing quantity is 5%-50%, optimum admixing quantity is 20%-30%; (6) flyash, internal admixing quantity is 5%-50%, optimum admixing quantity is 40%-50%; (7) water-proofing agent, internal admixing quantity is 0.5%-5.0%, optimum admixing quantity is 2.5%; (8) expansion agent UEA, internal admixing quantity is 6%-12%, optimum admixing quantity is 8%-10%, one selected from water-proofing agent and expansion agent can be admixed; and (9) polypropylene fibre, external admixing quantity is 0.1-2.0 kg/cu.m, optimum admixing quantity is 1Kg/cu.m.

Description

technical field [0001] The invention relates to a special concrete, in particular to an anti-seepage and anti-crack concrete suitable for ready-mixing and pumping. Background technique [0002] At present, many public facilities such as large bridges, river embankments, and large stadiums constructed at home and abroad have more or less cracks in structural defects, and some parts have extended to the steel bars, which has damaged the integrity of concrete buildings. Leakage occurred, the water in the basement became damp, the safety of the bridge was questioned, and it was eventually demolished and rebuilt. Many public places were forced to close, causing a lot of waste of manpower and material resources, and seriously threatening the safety of people's lives and property. The reason is mainly due to the concentration of internal stress during the use of concrete, which causes microcracks to appear in the parts with structural defects inside, and gradually expands and exten...

AI Technical Summary

Problems solved by technology

However, its expensive price and complex operation process make its application limited to on-site mixing or special concrete with special requirements, and cannot be widely used

Another reason why the above three types of fibers cannot be used on a large scale in the field of ready-mixed concrete is that the concrete mixed with these types of fibers has a large slump loss, small expansion, and poor workability, which is not conducive to long-distance transportation and pumping construction.

[0005] In view of the deficiencies of expansion cracking prevention and traditional fiber cracking prevention methods, synthetic fibers are used to prepare concrete to prevent concrete cracks at home and abroad. However, when applied to ready-mixed concrete, the slump loss is large, the expansion degree is small, and the pumping performance Poor, not widely used in the ready-mixed concrete industry

The engineering community generally believes that polypropylene fiber is a low elastic modulus fiber, with a small amount, which has little effect on the compressive strength, flexural strength, and tensile strength of concrete, and cannot be used as a structural performance enhancing material.