Abstract
The self-compacting concrete (SCC) was invented to overcome the compaction problems in deep sections, owing to its perfect workability characteristics. Steel fibers when used with SCC would affect the required fluidity characteristics but improve its impact resistance. In this research, an experimental work was conducted to evaluate the impact response of micro-steel fiber-reinforced SCC, under flexural impact. A 5.47 kg free-falling mass was dropped repeatedly from 100 mm height on the top center of 270 mm-length beam specimens. Eight mixtures with two design grades of 30 and 50 MPa were prepared to distinguish the normal and high-strength SCCs. The distinguishing variable for each design grade was the fiber content, where four volumetric contents of 0%, 0.5%, 0.75%, and 1.0% were used. The test results showed that the impact resistance and ductility were significantly improved due to the incorporation of micro-steel fibers. The percentage improvements were noticeably higher at failure stage than at cracking stage. For the 30 MPa mixtures, the maximum percentage improvements at cracking and failure stages were 543% and 836%, respectively. Weibull’s linear correlations with R2 values of 0.84 to 0.97 were obtained at the failure stage, which meant that the impact failure number followed the Wiebull distribution.
Highlights
Concrete is known for its weakness in tension
The results showed that using crumb rubber as a replacement of sand led to a higher impact resistance, which was higher as the content of crumb rubber increased
The results showed that the influence of freeze–thaw cycles on the cracking and failure impact resistances was slight up to 200 cycles, while the cracking impact resistance of the beams decreased significantly after 250 cycles of freeze and thaw
Summary
Several types of loading induce tensile stresses, among which is bending, which induces flexural tensile and compressive stresses It is essential in the design of flexural members, such as beams and slabs, to add sufficient quantity of reinforcing steel in the tension zone, to withstand the applied tensile flexural stresses. Examples of undesired accidental sudden impacts are hits from collision of moving vehicles and gravity falling objects from higher altitudes, or due to hits by military projectiles in the case of wars or terrorist attacks [1,2,3,4,5]. Some other types of structures or constructional elements are already designed to withstand repeated impact forces. The dropweight test is the more usual test used to examine the performance of concrete material and structural performance against impact loads, while the one recommended by ACI
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
