Study on sea sand as a partial replacement for fine aggregate

Sand researches around the world are in continuous search for the alternatives of sand. Fine aggregate is an important constituent of concrete and is required in large quantities. Generally, river sand is used as fine aggregate. Due to the increase in the utilization of concrete in construction sector, the need for river sand has been increased enormously. Hence, the abundant sea sand can be used as an alternative of river sand partially.The sea sand samples before (samples A and C) and after mineral extraction were utilized to replace for fine aggregate. The mineral extracted chiefly includes ilmenite, zircon, rutile, sillimanite and super garnet was confirmed by an analytical technique Energy-dispersive X-ray analysis (EDXA). Physical properties of these sands were recorded. Results reveal that the angle of internal friction (Ø) was high and low in sample A and C, but an opposite trend was observed for specific gravity.  Except sample D, remaining samples belong to grade II size.   Concrete cubes were laid for M35 grade concrete with the combinations of the above samples. The fine aggregate proportion from the design mix was replaced partially by 20% of sea sand. Compressive strength test and pull out test and the behaviour of concrete were conducted on the various soil specimens and the results were tabulated. The strength tests were conducted at 7, 14 and 28 days of water curing. Compressed strength, band strength as well the weight kg-1of the concrete did not affected by replacement of either sample A (10%) or sample B (20%). Proposed replacement is economically cheaper. Considering laboratory studied, we recommended to utilized sea sand for partial replacement for fine aggregate.Â

Mechanical Properties of Randomly Oriented Calotropis Gigantea Fiber-Reinforced Phenol Formaldehyde Biocomposites

Mechanical properties such as tensile, flexural and impact, of randomly oriented Calotropis Gigantea Fiber (CGF) -reinforced Phenol Formaldehyde (PF) biocomposites were studied based on the five different fiber loadings (10, 20, 30, 40, and 50 vol%) and three different fiber lengths (3, 9, and 15 mm). The critical fiber length and optimum fiber loading were identified with the maximum level of mechanical properties in this composite. The fractured surfaces of composites after testing were studied by scanning electron microscope (SEM). The results revealed that the addition of CGFs is improving the mechanical properties of the PF composite. The properties of composites reach the properties of the neat resin sample at 20 vol% of all the cases. The critical fiber length and the optimum fiber loading to obtain the maximum mechanical properties were identified as 9 mm and 40 vol% respectively. Experimental tensile property values were compared with theoretical values and found to be in good agreement

Effects of Addition of Prosopis Juliflora Fiber on the Physical and Mechanical Properties of Wood Dust and Coir Pith Particle Reinforced Phenol Formaldehyde Hybrid Composite

In this study, Wood Dust (WD)/Phenol Formaldehyde (PF) and Coir Pith (CP)/PF composites were hybridized with the Prosopis Juliflora Fiber (PJF) to obtain the hybrid composites. Composites were prepared by hand moulding technique. The weight percentage of particles and fibers are fixed in the ratio of 1:1. Mechanical properties such as tensile, flexural and impact strengths were evaluated as a function of the particle and fiber loadings. The results show that the properties of both the WD and CP composites obviously improved by the addition of the PJF. The improvement in WD/PF composites was obviously higher than the CP/PF composites for all loadings. The WD/PJF/PF hybrid composites exhibited better tensile (strength of 48.9 MPA and modulus of 1262.1 MPa, respectively), flexural (strength of 55.4 MPa and modulus of 1344.3 MPa, respectively), and impact properties (1.32 KJ/m2).Â

Właściwości mechaniczne żywic fenolowo-formaldehydowych wzmocnionych włóknami Prosopis Juliflora.

In this paper, an attempt was made to use Prosopis juliflora fibres (PJFs) as a reinforcing agent for phenol formaldehyde (PF) composites. Mechanical properties of the composites were studied for various fibre aspect ratios (FAR) and fibre loadings (FL). A scanning electron microscope (SEM) was used to study the fractured surface of the composites. The peak range of mechanical properties was identified for composites with a FAR of 136 and fibre loading of 23.53 wt%. This study shows that the optimum FAR and fibre loading for PJFs were found to be 136 and 23.53 wt% in order to achieve good reinforcement with better mechanical properties in the PF resin matrix. Experimental results were observed to be in very good agreement with the theoretical.W pracy podjęto próbę wykorzystania włókien Prosopis juliflora jako środka wzmacniającego żywice fenolowo-formaldehydowe. Przy użyciu elektronowego mikroskopu skaningowego zbadano powierzchnie przełomu kompozytów. Dla różnych wartości wydłużenia włókien (46, 136 i 227 mm) i udziału procentowego włókien w matrycy (4.88, 10.34, 16.51, 23.53 i 31.58 wt%) zbadano właściwości mechaniczne kompozytów. Na podstawie badań stwierdzono, że optymalne wydłużenie i zawartość włókien w matrycy to odpowiednio 136 mm i 23,53 wt%. Wyniki eksperymentalne charakteryzowały się dobrą korelacją z wynikami teoretycznymi