Comparative Analysis of Waste, Steel, and Polypropylene Microfibers as an Additive for Cement Mortar

Abstract

This study presents the results of laboratory experiments conducted to determine the mechanical parameters for cement mortar with various quantities of waste fibers, polypropylene microfibers, and steel microfibers. Waste fibers were used as samples and obtained using an end-of-life car tire recycling process. For comparison, samples with the addition of steel and polypropylene microfibers were tested. The same degrees of fiber reinforcement were used for all types of fibers. Ultimately, 22 mixtures of cement mortar were prepared. The aim of this study is therefore to present and compare basic mechanical parameter values. Compressive strength, flexural strength, fracture toughness, and flexural toughness were of particular interest. A three-point bending test was performed on three types of samples, without a notch and with a notch of 4 and 8 mm. The results show that the use of steel microfibers in the cement mortar produces a product with better properties compared to a mixture with steel cord or polypropylene fibers. However, the cement mortar with the steel cord provides better flexural strength and greater flexural toughness factors compared to the cement mortar with polypropylene fibers. This means that the steel cord is a full-value ecological replacement for different fibers.

Cracking Behavior and Deflections in Recycled-Aggregate Beams Reinforced with Waste Fibers Subjected to Long-Term Constant Loading

“…Steel cords differ in terms of the length and diameter of their fibers, due to the various types and sizes of tires (Figure 2). Steel cord specifications were determined in previous studies [7,9,10] Portland cement CEM I 42,5 R was used in amounts of 400 kg/m³. Superplasticizer Silka ViscoCrete 5-600 was applied in amounts of 1% of cement weight.…”

“…Steel cords differ in terms of the length and diameter of their fibers, due to the various types and sizes of tires (Figure 2). Steel cord specifications were determined in previous studies [7,9,10]. A total of 8 mixtures, which differed in terms of the aggregate used, were tested.…”

“…An example of such material is steel fiber (steel cord), which is a waste product of the recycling of car tires [ 7 ]. The effects of steel cord on many properties of concrete were already widely studied [ 7 , 8 , 9 , 10 ]. However, there were no studies on the effects of steel cord on the long-term properties of concrete.…”

Effect of Tire Cords, Steel and Polypropylene Fiber Content on the Fatigue Response of Cement-Based Mortars

“…Note, the steel cord lengths and fiber diameters varied due to the different types and sizes of tires. Steel cord specifications were determined in previous studies [21,30,31]. See Table 1 and Fig.…”