THE STUDY OF THE MANHOLE COVER STRENGTH WITH FINITE ELEMENT METHOD THE STUDY OF THE MANHOLE COVER STRENGTH WITH FINITE ELEMENT METHOD

Abstract

This project had the objective to study the strength of the grate manhole cover with the Finite Element Method. The cover had the dimensions 540 x 780 x 100 mm using the low-carbon steel ASTM A36 as material. Two different structure designs of manhole cover were obtained using different thickness of the rim and grate of the structure. The manhole no.1 had the thickness of 10 mm for the rim and 5 mm for the grate while the manhole no.2 had the thickness of 5 mm for the rim and 3 mm for the grate. These two designs of manhole cover were used to study about the strength of the structure, by specifying the stimulated load rate 15,000 kg, of six-wheel truck with one shaft and double tires, and all the load rested on the rear shaft.

The results found that both manhole designs had enough strength to support the tested load without any damage and the stresses occurred on both structures were lower than the yield stress of material. However, the manhole no.1 had more strength than the manhole no.2. The safety factor of the manhole no.1 was 2.7 greater than that of the manhole no.2 which had safety factor around 1.5.