Mechanical Properties of Cast-in Anchor Bolts Manufactured of Reinforcing Tempcore Steel.

Bahleda Bahleda,Nový Nový,Hasajová Hasajová,Bujňáková Bujňáková,Koteš Koteš

doi:10.3390/ma12132075

Abstract

The tempcore process is implemented in rolling mills to produce high strength reinforcing steel. Besides being used as reinforcement, rebars are also used as the base material for the manufacturing of anchor bolts. The mechanical properties of reinforcement bars used in Europe are assessed in accordance with Eurocode without the recommendations for cast-in anchor bolts. The material properties of Tempcore rebars are not homogenous over the bar cross section. The European Assessment Document (EAD) for the cast-in anchor bolts does not exactly specify the mechanical properties of the thread part. The aim of these experiments is to show the different mechanical properties of rebars and their thread parts. The experiments were performed on rebars modified by peeling to characterize the reduction of diameter in a thread part. As a possible way to predict mechanical properties in a non-destructive way, the hardness tests were performed. Next, the application of the correlation relationship between hardness and tensile strength has been determined. The paper formulates preliminary recommendations for assessment of the cast-in anchor bolts in practice.

Highlights

The mechanical properties of reinforcement bars used in Europe are assessed in accordance with Table C.1 of EN 1992-1-1 [1] by characteristic values of yield strength, a minimum ratio ft /fy, and a minimum characteristic strain at maximum force εuk
As the ultimate limit state of reinforced concrete structures is most often characterized by development of plastic hinges, the three earlier mentioned characteristics are assumed to be enough to guarantee a ductile behaviour of the structure at the ultimate limit state (UTS)
The paper presents a verification of mechanical properties of Tempcore rebars modified by peeling

Summary

Introduction

The mechanical properties of reinforcement bars used in Europe are assessed in accordance with Table C.1 of EN 1992-1-1 [1] by characteristic values of yield strength, a minimum ratio ft /fy , and a minimum characteristic strain at maximum force εuk. Besides being used as reinforcement, rebars are used as the base material for the manufacturing of anchor bolts (see Table 3.1 of EN 1993-1-8 [2]) Such bolts are typically manufactured by peeling off the ribbed perimeter of the bar and cutting or rolling a thread on the bar. They are used to anchor concrete or steel connection for concrete structures (e.g., foundations, base columns, slabs, walls, and similar applications). In the absence of a European standard for anchor bolts, including the material recommendation, Materials 2019, 12, 2075; doi:10.3390/ma12132075 www.mdpi.com/journal/materials

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