Multi-Physics Analysis for Rubber-Cement Applications in Building and Architectural Fields: A Preliminary Analysis

Abstract

Generally, in most countries, there are no strict regulations regarding tire disposal. Hence, tires end up thrown in seas and lands as well as being burnt, harming the living beings, and are therefore considered a very dangerous pollution source for the environment. Over the past few years, several researchers have worked on incorporating shredded/powdered rubber tires into cement-based material. This strategy shows a dual functionality: Economic–environmental benefits and technological functionalization of the building material. Rubber-modified cement materials show interesting engineering and architectural properties due to the physical-chemical nature of the tire rubber aggregates. However, the abovementioned performances are affected by type, size, and content of polymer particles used in the cement-based mixtures production. Whereas an increase in the rubber content in the cement mix will negatively affect the mechanical properties of the material as a decrease in its compression strength. This aspect is crucial for the use of the material in building applications, where proper structural integrity must be guaranteed. In this context, the development of innovative manufacturing technologies and the use of multi-physics simulation software represent useful approaches for the study of shapes and geometries designed to maximize the technological properties of the material. After an overview on the performances of 3D printable rubber-cement mixtures developed in our research laboratory, a preliminary experimental Finite Element Method (FEM) analysis will be described. The modeling work aims to highlight how the topology optimization allows maximizing of the physical-mechanical performances of a standard rubber-cement component for building-architectural applications.

Influence of Waste Tire Rubber Particles Size on the Microstructural, Mechanical, and Acoustic Insulation Properties of 3D-Printable Cement Mortars

“…The bulk density trend is in line with the lower σc and σf in RCMs, which also depend on the weak rubber-cement interface adhesion and the soft properties of polymer fillers, resulting in premature cracking in the surrounding cement matrix. The results of this work are consistent with previous experimental studies [5,16,37,38]. However, two noteworthy findings can be deduced from the compressive strength results.…”

“…This is attributable to the shredding treatment. To obtain a greater fineness degree, more grinding cycles are required, resulting in more irregular shaping of the rubber particles [16].…”

“…The sand-rubber replacement reduces ρ-values. Unit weight drop can be mainly attributed to the lower specific gravity of the rubber particles than mineral ones, the contribution of ITZ voids, and the variation in the overall porosity depending on w/c ratio [5,16,36]. The most relevant density reduction is observable in RP100 mix, where the total incorporation of fine polymeric fraction implies a higher weight content of rubber in the material.…”

“…The objective is to combine the technological functionalities conferred by rubber with the performance of additive manufacturing in terms of design flexibility, structural optimization, and low pollution. Several efforts were already conducted by the authors on this topic, involving preliminary printability and print quality studies to explore the potential of incorporating recycled tire rubber particles into printable cementitious mixes [5,7,13], experimental characterization on durability analysis [13], the effect of rubber-based modification on thermal insulation properties [7,15], first mechanical investigations and modelling [5,7,15,16]. From the perspective of rational production of secondary raw materials by the tire recycling companies, economic impact and material performance, the novel purpose of the present study is to deepen in detail the influence of rubber particle size on the fresh and hardened properties of printable mortars.…”

Topology Optimisation in Structural Steel Design for Additive Manufacturing

“…At a coarser scale, construction composite materials can also be enhanced under the assistance of TO. That is the case of the types of cement with an enclosure of rubber waste [515] or Carbon Fibre Reinforced Plastics (CFRP) [516].…”