Analysis of Crack Width Development in Reinforced Concrete Beams

Abstract

The reliability and durability of reinforced concrete structures depend on the amount of concrete cracking. The risk associated with cracks generates a need for diagnostic methods for the evaluation of reinforced concrete structures. This paper presents the results of a study of 10 single-span reinforced concrete beams to follow the process of crack formation and changes in their width. The beams were loaded to failure with two forces in a monotonic manner with unloading and in a cyclic manner. Continuous observation of the crack formation process was provided by the digital image correlation system. The simplified method for estimating the maximum crack width is proposed. The presented results confirmed the stochastic character of the process of crack formation and development. The maximum crack widths calculated on the basis of the proposed formula were on the safe side in relation to those calculated according to Eurocode 2. It was also confirmed that the distances between cracks do not depend on the loading manner. Hence the density function describing the distribution of distances between cracks can be used to assess the condition of reinforced concrete elements. The research has also shown the suitability of the DIC system (ARAMIS) for testing concrete elements.

Shear Capacity of Reinforced Concrete Beams under Monotonic and Cyclic Loads: Experiments and Computational Models

“…In addition to actuators enabling the implementation of the loading program, measuring equipment was used, which included the HBM measuring set and the DIC system (ARAMIS) [ 10 , 11 ]. The Hottinger Baldwin Messtechnik measurement set, consisting of two modular measuring amplifiers and inductive transducers (road sensors), recorded loads and displacements ( Figure 7 ).…”

“…The Hottinger Baldwin Messtechnik measurement set, consisting of two modular measuring amplifiers and inductive transducers (road sensors), recorded loads and displacements ( Figure 7 ). The optical measuring system, ARAMIS, [ 10 , 11 ], was applied to analyze, calculate and document strain fields for the prepared beam surfaces ( Figure 8 ). Additionally, using the analogue voltage outputs of the load controller, the entire test apparatus was synchronized, and the automatically set force was used to control the measurements performed by the HBM and optical systems [ 12 ].…”

“…This allows non-contact measurements that do not interfere with the loading process. The DIC system (ARAMIS) [ 11 , 12 ] ( Figure 8 ) used in this study was equipped with two tripods with two cameras each. The system made it possible to measure strains, spatial deformations and cracks on the side surface of the beams during the entire loading process on two surfaces measuring 2.00 m × 1.50 m.…”

Development of Crack Width Prediction Models for RC Beam-Column Joint Subjected to Lateral Cyclic Loading Using Machine Learning

“…Although design codes impose limitations on crack widths based on empirical formulae, there is often uncertainty associated with determining crack width propagation, due to cyclic/seismic loads [9][10][11]. The propagation in crack width can reduce the structure's service life by accelerating the corrosion of steel reinforcement through the penetration of moisture, vapor, saltwater, and chemical gasses to the structural members [2,12,13]. The crack width initiation and propagation in reinforced concrete members could be estimated using classical theories by assuming the distribution of the bond stress as a member is subjected to tension with constant bending moment [14,15].…”

A Combined Positioning Method Used for Identification of Concrete Cracks

“…Some long-distance structures such as pipelines, bridges, highways and railways play an important role in national economies and are prone to be damaged arising from the falling stone, sinkhole collapse and heavy loads. Under the action of these adverse loads, these structures are prone to long-term cumulative damage or sudden damage [1,2]. Many scholars have adopted different methods to monitor concrete cracks [3][4][5].…”