Method for predicting plastic shrinkage cracking of cement mortar material

Abstract

The invention relates to a method for predicting plastic shrinkage cracking of a cement mortar material. The method comprises the following step of: substituting four cement-based material composition parameters comprising water cement ratio (Wc), cement sand ratio (Cs), fiber content (Fc) and fiber length (F1), water evaporation speed (Er) and demixing degree (Dd) and restraint degree (Rd) of the cement-based material into the following formula: K = 13.8822 - 14.0949Wc - 2.8247Cs + 0.5293Fc + 0.0022F1 - 17.0650Er + 0.2582Dd + 0.9436Rd, wherein the K is anti-cracking index. When the K value is more than 1.41, the cement-based material test piece is not cracked; when the K value is less than 0.99, the test piece is cracked; and when the K value is between 0.99 and 1.41, the test piece is cracked in certain probability. A multiplex constitutive equation of plastic shrinkage cracking of the mortar is constructed by using the parameters with great influence on the cement-based plastic shrinkage cracking, the tendency of early plastic shrinkage cracking of the cement-based material can be accurately predicted, and the method can be widely applied to early prediction of the plastic shrinkage cracking of the mortar.

Description

Technical field [0001] The invention relates to a method for plastic shrinkage cracking of cement-based materials. It can be used for the early qualitative prediction of plastic shrinkage cracking tendency of cement mortar materials. It belongs to the field of materials science and engineering. technical background [0002] Cement concrete is one of the largest and most widely used building materials in the world. Because cement concrete has the advantages of wide application range, low price, easy pouring and forming, relatively durable, and can effectively use some industrial solid wastes to make energy-saving and environmentally-friendly building materials, it will still be irreplaceable in modern engineering construction in my country in the 21st century. Main building materials. [0003] However, it is undeniable that cement concrete has disadvantages such as self-weight, low tensile strength, small ultimate tensile strain, poor impact strength, and easy plastic loss, shrink...

AI Technical Summary

Problems solved by technology

However, so far, a multi-component constitutive equation for plastic shrinkage cracking including cement-based material composition, environmental conditions, initial structural parameters and constraints has not been given, so it is expected to be used for early prediction of plastic shrinkage cracking of mortar