Strength Properties of Various Types of Fiber-Reinforced Concrete for Production of Driven Piles

Abstract

This paper presents the results of static and dynamic tests of fiber-reinforced and unreinforced concrete samples under laboratory conditions. Concrete samples reinforced with steel and non steel fibers were tested. The dynamic tests were carried out on the stand by applying falling weight impacts on the concrete samples. The impact testing of samples included two stages of deformation: until the first defects appeared in the samples and until their complete destruction. The impact resistance of the samples was evaluated according to the energy input of the hammer with registration of the type, size and volume of the defects. It was revealed that the type of fibers has a different effect on the static and impact resistance of fiber concrete. Correlational dependencies used for predicting the strength and energy parameters of fiber concrete in their comparative evaluation have been obtained. It has been determined that the static strength and impact resistance of fiber concrete may not be identical, i.e., a high static strength in fiber concrete does not always provide a high impact resistance. The impact resistance of fiber concrete when tested before the first defects appear is always lower than when tested before complete failure.

The Influence of Backfill on the Driving Energy Intensity and Axial Load Resistance of Piles with Shaft Widenings: Modeling Research

“…One approach to address this challenge is the development and utilization of unconventional pile shaft shapes. Such variations encompass piles with shaft widening, thickening, profiled surfaces, and telescopic geometries, among others [1][2][3][4][5]. Owing to the distinctive characteristics of their shaft shapes, these piles demonstrate more efficient interaction with the surrounding soil, resulting in a significantly greater load resistance than conventional prismatic or cylindrical piles.…”