Caracterização de blocos de concreto confeccionados com resíduos de quartzito, seringueira e polpação de celulose

Abstract

The use of waste in order to respond to the environmental problem of its disposal and at the same time give it a functional destination is the focus of numerous studies on the current issue of sustainability. The aim of this study was to physically and mechanically evaluate blocks made from quartzite powder, primary pulping sludge and rubber tree trunk particles. To produce the blocks, the primary pulp sludge and rubber tree sludge were subjected to three treatments: immersion in hot water, aluminum sulphate and synthetic termite slime. The formulation used to produce the blocks was 8.2% cement, 45.9% pebbles, 45.9% sand, replaced by quartzite powder in a proportion of 33% compared to sand, with the addition of two different types of lignocellulosic material, 2.26% primary pulp sludge and 2.5% rubber tree trunk particles. The cement was cured under ambient conditions for 28 days. The blocks were then subjected to analysis of their physical and mechanical properties and air permeability. The quartzite powder showed a good relationship with the cement, a fact attributed to its high silica content (70.1%), which could influence the durability of the cement blocks. Primary pulp sludge showed potential as a reinforcement, especially when treated with aluminumsulfate. This treatment gave the blocks a higher density (1.71 g/cm³) and consequently reduced porosity (14.3%), water absorption (9.17%) and permeability. The blocks had better compressive strength (4.39%) when treated with aluminum sulphate. Thus, the incorporation of cellulose pulp proved promising. With regard to the use of rubber tree trunk particles, the treatments did not show good results in the properties analyzed. Despite this, all the treatments met the normative requirements of NBR 6136 (ABNT, 2016) for water absorption (<13%). Thus, this research has provided an alternative design for the production of blocks that aims to valorize mining and forestry waste, contributing to the sustainability of the civil construction sector.