Experimental Investigation Of Nail Joint Performance In Micandra Spruceana Wood: Effect Of Nail Length And Configuration

Abstract

The present study conducts the nail joint load-bearing capacity and the deformation behavior of Higuerilla wood (Micandra Spruceana) to assess the wood's suitability for construction industry. The standardized double shear parallel to the grain test consisted of 240 specimens which were divided into 3 groups each using 2 inches, 3 inches, and 4 inches nails. The nails quantity and design varied according to each case with thirty tests conducted to assess nail extraction resistance, wood density and moisture content. The studies were carried out at the materials testing laboratory of the Faculty of Civil Engineering, National Engineering University (UNI). Results indicate reduced characteristic experimental loads ranging from 30 kg to 66 kg per nail for different nail configurations with 2-inch nails, 45 kg to 130 kg per nail for 3-inch nails, and 65 kg to 126 kg per nail for 4-inch nails. The JUNAC recommendations and the Johansen model were also calculated to obtain theoretical values. The comparative study shows that the ultimate stress values per nail for Higuerilla wood are close to results of group "C" woods such as Punga, Rubber, Catahua Amarilla, Mahogany, and Cumala, with differences only being from 5% to 35% depending on proximity of density between Higuerilla and listed woods.