M.P. Salaimanimagudam

Bio: M.P. Salaimanimagudam is an academic researcher. The author has contributed to research in topics: Fabrication & Optimization problem. The author has an hindex of 4, co-authored 6 publications receiving 49 citations.

Impact Response of Preplaced Aggregate Fibrous Concrete Hammerhead Pier Beam Designed with Topology Optimization

Abstract: This research aimed to study the impact response of topology optimized hammerhead pier beam (HPB) based on the density approach The HPB is prepared with the concept of preplaced aggregate fibrous concrete (PAFC) comprising two primary approaches; first, the coarse aggregate and fiber are prepacked into the designed formwork Second, the gaps between the aggregate and fiber are filled with cement grout In this work, an attempt has been made to study an impact response of HPB made with PAFC Five HPBs were prepared and strengthened with steel fibers with two different schemes, Firstly, the HPB was reinforced with a full cross-section at 2 and 4% of steel fiber, while another set of beams were only reinforced in the tension zone with the same amount of fibers The study parameters included compressive strength, impact strength, impact ductility index, number of main and secondary cracks, and failure pattern It was observed that the PAFC had an increase in compressive strength up to 569%, compared with nonfibred concrete A fully fibered concrete beam with 4% fiber addition was the best at taking impact, and the initial crack and failures were observed at 27251 J and 30098 J, respectively, compared with non-fibered and tension zone fibered concrete beams Compressive local damage and transverse flexural cracks were observed, which had caused initial cracks and final failure The HPB with a full reinforced scheme at 4% dosage exhibited higher impact strength than the normal concrete and beam reinforced only in the tension zone

Experimental Study on GFRP Strips Strengthened New Two Stage Concrete Slabs under Falling Mass Collisions

Abstract: In the course of global terrorist events prominent risks were faced by military and civilian infrastructure. Subsequently, the design of structures to resist impact load has become vital in the design process. Fibre reinforced polymer sheets were utilized as exceptional material to enhance the resistance of the structure to impact load. Until now, most researchers focused on the response of Fibre Reinforced Polymer (FRP) strengthened slabs under static load. Extensive research on the impact response of FRP strips strengthened slabs is relatively rare and the outcome of these investigations have been controversial. Therefore, it is vital to comprehend the response of FRP strengthened slabs subjected to falling mass collisions. In this study, impact response of Glass Fibre Reinforced Polymer (GFRP) strips strengthened Two Stage Reinforced Concrete Slabs (TSRCS) have been examined through experiments. Two different widths of 50 mm and 75 mm GFRP strips were used in perpendicular and oblique ways in one and two directions while strengthening TSRCS. In Total, a nine 1,000 mm × 1,000 mm × 60 mm TSRCS were fabricated and later impacted by a steel cylinder of 55 kg dropping at the centre from a 3,000 mm height. Study parameters analysed to discover the impact response of TSRCS include, impact-force history, acceleration, damaged area (top and bottom face), damage area ratio, damage volume ratio, and damage pattern. The results revealed that the slab strengthened with 75 mm GFRP strips was more effective in alleviating damage volume ratio compared to the 50 mm GFRP strips. Also, the obtained results in this study shed light on the impact performance of two stage reinforced concrete slabs.

Drying shrinkage and creep properties of prepacked aggregate concrete reinforced with waste polypropylene fibers

Abstract: Prepacked aggregate concrete (PAC) is a particular form of concrete that is manufactured by placing and packing aggregates with different sizes in a formwork, and the spaces between the aggregates are then filled through the injection of cement grout with high flowability. This study proposed the prepacked aggregates fiber-reinforced concrete (PAFRC), which is a newly developed concrete, with a unique combination of coarse aggregate and short polypropylene (PP) fiber that is premixed and placed in the formworks. This study presents the outcomes of an investigational work that addresses creep and drying shrinkage performance in addition to the strength development of PAFRC specimens. In addition, palm oil fuel ash (POFA) was used at the substitution level of 20%. Six mixes comprising fiber volume fractions of 0–1.25% with a length of 30 mm were cast by gravity technique. Another six mixtures with the same fiber volume fractions were cast using a pump to inject the grout into the formwork. The experimental outcomes exposed that utilization of waste PP fibers and POFA improved the compressive strength of PAFRC mixes. The drying shrinkage and creep of PAFRC mixes reduced significantly with the addition of waste PP fibers. Moreover, due to the lower drying shrinkage and creep, as well as the unique production technique, PAFRC could be used for several innovative applications in construction.

Exploring the impact performance of functionally-graded preplaced aggregate concrete incorporating steel and polypropylene fibres

Abstract: This study investigates the impact response of Functionally-graded Preplaced Aggregate Fibrous Concrete (FPAFC) made with steel and polypropylene fibres against falling mass impact. FPAFC is a new type of concrete containing coarse aggregates and fibres pre-mixed and uniquely packed into an empty mold to develop a skeletal system. Subsequently, voids in the skeleton are filled with formulated cement grout. In this experimental study, twelve different concrete mixtures were produced with 2.4% dosage of mono and hybrid combinations of steel and polypropylene fibres to pioneer the potential use of fibres in FPAFC, for structures demanding impact resistance. Two functionally-graded schemes with various combinations of fibre dosage were considered to evaluate the most influential for impact resistance performance in FPAFC. In all, 180 cylindrical discs were prepared and tested under falling mass impact in conformity with ACI Committee 544 suggestions. Besides, Weibull distribution of two parameters was used to analyse discrepancies in the test's falling mass impact results. Impact strength was provided corresponding to reliability levels. Results revealed that a two-layer FPAFC exhibited lesser impact strength than single layer concrete. Additionally, choosing the appropriate fibre dosage and mono and hybrid fibre combinations showed the potential ability to achieve superior impact strength in FPAFC than a single two-layer concrete specimen. This phenomenon was due to the fibre bridging action and the three layers brought forth alleviated shear stress transfer in the interfacial transition zone. Thus, a superior composite action was attained in the developed FPAFC. The results obtained from this investigation provides the benchmark data for further in-depth scientific exploration of FPAFC under impact.

Impact Performance of Steel Fiber-Reinforced Self-Compacting Concrete against Repeated Drop Weight Impact

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 547 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%, 05%, 075%, and 10% 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 084 to 097 were obtained at the failure stage, which meant that the impact failure number followed the Wiebull distribution