Related Experiment Video
Updated: Nov 10, 2025
11:07
Preparation of Aligned Steel Fiber Reinforced Cementitious Composite and Its Flexural Behavior
Published on: June 27, 2018
11.4K
Experimental Evaluation of PSC Structures from FRP with a Prestressing Strengthening Method
Tae-Kyun Kim1, Sang-Hyun Kim1, Jong-Sup Park1
1Department of Infrastructure Safety Research, Korea Institute of Civil Engineering and Building Technology, 283, Goyang-daero, Ilsanseo-gu, Goyang-si 10223, Gyeonggi-do, Korea.
Materials (Basel, Switzerland)
|April 3, 2021
Summary
Strengthening aged prestressed concrete (PSC) structures is crucial. The near surface mounted (NSM) and external prestressing (EP) methods using fiber-reinforced polymers significantly enhance stiffness, with EP showing the best results.
Area of Science:
- Civil Engineering
- Materials Science
Background:
- Prestressed concrete (PSC) structures suffer long-term degradation due to aging and environmental factors like moisture, chloride, and carbonation, leading to prestress loss.
- This degradation necessitates structural strengthening to maintain performance and extend service life.
Purpose of the Study:
- To evaluate the effectiveness of near surface mounted (NSM) and external prestressing (EP) methods for strengthening degraded PSC structures.
- To assess the performance of fiber-reinforced polymers (FRPs), specifically carbon fiber-reinforced polymers (CFRPs), in enhancing structural integrity.
Main Methods:
- Fabrication of 12 types of PSC specimens utilizing NSM and EP strengthening techniques.
- Conducting four-point flexural tests to evaluate the stiffness and performance of strengthened specimens.
- Comparison of strengthened specimens against a control PSC specimen.
Main Results:
- All specimens strengthened with NSM (with and without prestressing) and EP methods exhibited a 50-60% increase in stiffness compared to the control specimen.
- The external prestressing (EP) method, when combined with prestressing, demonstrated the most significant strengthening effect.
- Fiber-reinforced polymers were utilized for their high tensile strength and resistance to corrosion.
Conclusions:
- Both NSM and EP methods are effective in enhancing the stiffness of prestressed concrete structures.
- The EP method offers superior strengthening capabilities, particularly when combined with prestressing.
- The findings are expected to inform the strengthening and performance improvement of real-world PSC structures.
Related Concept Videos
01:20Prestressed Concrete
449
Prestressed concrete is a construction technique designed to enhance the strength and durability of concrete structures. This method involves the application of a pre-set tension to high-strength steel strands used as reinforcement before the concrete is subjected to its working loads. The primary aim of prestressing is to place the concrete in a state of compression, in order to counteract the tensile forces it will experience in service. This pre-compression helps prevent crack formation in...
449
01:22Fiber Reinforced Concrete
190
Fiber-reinforced concrete significantly enhances the structural and nonstructural properties of traditional concrete by incorporating fibers like steel, glass, and polymers. These fibers, varying from natural ones such as sisal and cellulose to manufactured ones like polypropylene and Kevlar, are mixed into hydraulic cement with aggregates. Steel fibers, often preferred for their robustness, contribute to improved ductility, toughness, and post-cracking performance. The concrete is classified...
190
01:23Design of Prismatic Beams for Bending
493
The design of prismatic beams, structural elements with a uniform cross-section, focuses on ensuring safety and structural integrity under load. The design process begins by determining the allowable stress, either from material properties tables, or by dividing the material's ultimate strength by a safety factor. This safety factor is essential for accommodating uncertainties, and varies depending on the material—timber, steel, or concrete—with each having unique strength and...
493
01:15Posttensioned Masonry Walls
283
Post-tensioned masonry walls use high-strength steel rods or flexible tendons to enhance the strength and efficiency of masonry structures. These elements are securely anchored to the foundation and extend vertically either within the cores of the masonry units or between the masonry wythes. The construction process involves building the wall with these tensioning elements in place and allowing the mortar to fully cure.
Following the curing process, the tensioning begins. Steel rods are...
283
01:12Non-destructive Tests for Concrete Strength
266
The rebound hammer test, also known as the Schmidt hammer test, is a non-destructive technique for evaluating the hardness of concrete and, indirectly, the strength of concrete. It operates on the principle that the rebound of a spring-driven mass from a concrete surface correlates to the surface's hardness. The device comprises a mass within a tubular housing, a spring mechanism, and a plunger that strikes the concrete. Upon release, the energy imparted to the mass by the spring causes it...
266
01:16Tensile Strength Considerations of Concrete
279
Considering the tensile strength of concrete involves recognizing that the theoretical strength of cement paste can be up to a thousand times higher than what is observed in practical applications. This significant discrepancy is largely attributed to the presence of microscopic cracks within the concrete. These cracks tend to amplify stress at their tips when a load is applied, a phenomenon explained by Griffith's theory of brittle fracture.
The dimensions and shape of a concrete specimen...
The dimensions and shape of a concrete specimen...
279