Properties and flexural behavior of self-compacting concrete with added coir fiber and POFA

This paper presents the mechanical properties and flexural behavior of selfcompacting concrete (SCC) with addition of 0.2%, 0.4% and 0.6% coir fiber (CF) as filler, and 10% palm oil fuel ash (POFA) as partial cement replacement. Fresh SCC-POFA-CF mixture was tested under slump flow and J-ring tests to determine its workability. SCC-POFA-CF cubes and cylinders were tested under compressive and tensile tests to determine its compressive strength, tensile strength, and flexural strength, while prisms were tested under four point bending load to determine its flexural behavior. It is found that workability of SCC-POFA-CF decreased when CF increased. The optimum percentage of CF in SCC mixture was found to be 0.4%. SCC-POFA-CF experienced less crack compared to the control specimen. This shows that CF in SCC prisms managed to control the crack propagation

Microstructure and Tensile Strength of Foamed Concrete with Added Polypropylene Fibers

An experimental study was conducted to improve the strength of foamed concrete by adding fibres reinforced material, polypropylene (PP) fibres. The aim of the study was to determine the effect of PP fibres on the microstructure and tensile strength of foamed concrete. Foamed concrete with density 1600 kg/m3 and 1800 kg/m3 were cast and tested with 0.05%, 0.10% and 0.15% percentage of PP fibres. The findings shows that foamed concrete added by PP fibres gave better performance in tensile strength compared to foamed concrete without PP fibres. With the addition of 0.05% of PP fibres, the tensile strength increased by 35.06% and 40.30% for foamed concrete with densities 1600 kg/m3 and 1800 kg/m3, respectively. Through the study of microstructure of foamed concrete, the air voids of foamed concrete with various densities and the interfacial adhesion between concrete and fibres were observed. The foamed concrete added by PP fibres gave better performance in tensile strength compared to foamed concrete without PP fibres

Microstructure and Tensile Strength of Foamed Concrete with Added Polypropylene Fibers

An experimental study was conducted to improve the strength of foamed concrete by adding fibres reinforced material, polypropylene (PP) fibres. The aim of the study was to determine the effect of PP fibres on the microstructure and tensile strength of foamed concrete. Foamed concrete with density 1600 kg/m3 and 1800 kg/m3 were cast and tested with 0.05%, 0.10% and 0.15% percentage of PP fibres. The findings shows that foamed concrete added by PP fibres gave better performance in tensile strength compared to foamed concrete without PP fibres. With the addition of 0.05% of PP fibres, the tensile strength increased by 35.06% and 40.30% for foamed concrete with densities 1600 kg/m3 and 1800 kg/m3, respectively. Through the study of microstructure of foamed concrete, the air voids of foamed concrete with various densities and the interfacial adhesion between concrete and fibres were observed. The foamed concrete added by PP fibres gave better performance in tensile strength compared to foamed concrete without PP fibres

Outcomes among trauma patients with duodenal leak following primary versus complex repair of duodenal injuries: An Eastern Association for the Surgery of Trauma multicenter trial

BACKGROUND: Duodenal leak is a feared complication of repair, and innovative complex repairs with adjunctive measures (CRAM) were developed to decrease both leak occurrence and severity when leaks occur. Data on the association of CRAM and duodenal leak are sparse, and its impact on duodenal leak outcomes is nonexistent. We hypothesized that primary repair alone (PRA) would be associated with decreased duodenal leak rates; however, CRAM would be associated with improved recovery and outcomes when leaks do occur. METHODS: A retrospective, multicenter analysis from 35 Level 1 trauma centers included patients older than 14 years with operative, traumatic duodenal injuries (January 2010 to December 2020). The study sample compared duodenal operative repair strategy: PRA versus CRAM (any repair plus pyloric exclusion, gastrojejunostomy, triple tube drainage, duodenectomy). RESULTS: The sample (N = 861) was primarily young (33 years) men (84%) with penetrating injuries (77%); 523 underwent PRA and 338 underwent CRAM. Complex repairs with adjunctive measures were more critically injured than PRA and had higher leak rates (CRAM 21% vs. PRA 8%, p \u3c 0.001). Adverse outcomes were more common after CRAM with more interventional radiology drains, prolonged nothing by mouth and length of stay, greater mortality, and more readmissions than PRA (all p \u3c 0.05). Importantly, CRAM had no positive impact on leak recovery; there was no difference in number of operations, drain duration, nothing by mouth duration, need for interventional radiology drainage, hospital length of stay, or mortality between PRA leak versus CRAM leak patients (all p \u3e 0.05). Furthermore, CRAM leaks had longer antibiotic duration, more gastrointestinal complications, and longer duration until leak resolution (all p \u3c 0.05). Primary repair alone was associated with 60% lower odds of leak, whereas injury grades II to IV, damage control, and body mass index had higher odds of leak (all p \u3c 0.05). There were no leaks among patients with grades IV and V injuries repaired by PRA. CONCLUSION: Complex repairs with adjunctive measures did not prevent duodenal leaks and, moreover, did not reduce adverse sequelae when leaks did occur. Our results suggest that CRAM is not a protective operative duodenal repair strategy, and PRA should be pursued for all injury grades when feasible. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV