Basics In Civil Engineering

Methods of Structural Design   There are many methods of design out of them following two are more popular: 1. Working Stress Method. 2. Limit State Method.   1. Working Stress Method: In this method, uncertainties such as correct estimation of load, possibility of occurrence of higher design load, material imperfection and geometrical imperfections in the structural members were taken into account in one single factor known as factor of safety. A particular section just reaching to yield stress at a maximum stressed fiber is considered to be a benchmark for estimating the capacity of the steel. Structural members are not allowed to stress more than allowable stress to ensure perfect elasticity. Different factors of safety were used to arrive allowable stresses for different types of stresses in structural members such as beam, column, tension member, base plate and fastners. Using estimated working/ service loads and their logical combinations the sections are designed using