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The reuse of waste from different sectors has proven to be an interesting alternative and, with increasing research, it is possible to use it as raw material for the manufacture of building products, reducing the disposal and exploitation of natural resources. Associated with the above, in the restoration of historic buildings it is recommended to use lime-based mortars as the material provides “breathability” to the support, however, incompatibility (chemical and/or physical, and/or mechanical) with the current materials may occur. In this context, the objective of this research is to evaluate the physical, mechanical, and chemical properties of mortars made with a binder (hydrated lime or Portland cement): sand, in the proportion 1: 3: (by weight) where waste was added: silica fume, glass powder, Amazon chestnuts, and biopolymer (obtained from milk that was unfit for human consumption). Mechanical tests (compressive strength and diametral compression strength), absorption (immersion and capillarity), and ultrasonic pulse were carried out at 28 days of age. It was found that the addition of silica fume, glass powder, and chestnut enabled better performance in the properties of the lime mortar with gains of over 500% in mechanical properties (mainly in tensile strength) and a reduction of around 13% in absorption, however, it is harmful to cement mortars due to the high-fat content of the chestnut (around 42%), impairing its performance. Finally, it was found that waste contributes to the concept of technological innovation and sustainable development as it provides benefits to the performance of lime mortars.

Concrete is a widely consumed material in the field of construction and is composed of fine and coarse aggregates mixed with water. However, its use is responsible for the emission of CO2into the atmosphere and high consumption of water, thus it is very important to develop more sustainable ways to produce concrete. One way to obtain sustainable concrete is to develop new concrete mixtures with admixtures that improve their performance and are not derived from petroleum. Thus, crude glycerin has potential as an admixture because of its mechanical properties, corrosion resistance, and renewability. In this context, this study aimed to evaluate the effect of crude glycerin as an admixture on the hydration of cement paste based on infrared absorption spectroscopy, scanning electron microscopy, compressive strength, and water absorption by capillarity and mortar immersion. The addition of 7% crude glycerin increased the hydration degree of the cement paste. This was verified by analyzing the changes in the infrared spectra and alkalinity of the cement paste. However, its addition to mortars in two different proportions of sand reduced the compressive strength. The absorption of water based on immersion showed that the addition of glycerin contributed to the slightly low absorption of the mortars, all of which were classified as good quality. In the case of the absorption of water by capillarity, all samples exhibited similar behaviors with similar values after 72 h.