Estimation of design load and distribution pattern for wooden classroom chairs in use at secondary schools in Ibadan, Nigeria

ABSTRACT The absence of an established design load constitutes a challenge to the engineering design of classroom furniture. This study developed a methodology for estimating design loads for single user (SU) and multiple user (MU) wooden classroom chair and desk combinations offered to secondary school students in Ibadan, Oyo State, Nigeria. Service load distribution patterns for the chair and desk members in normal, backward and front-reclining sitting postures were determined for 15 girls and 15 boys using bathroom scales. A T-test was used to compare the significance of the means of the proportions of users’ weights transferred to the chair and the floor. Design loads were 1 kN (SU) and 2.7 kN (MU) for chair and desk configurations, respectively. Each SU and MU leg should be designed to support 35% and 40% of the service loads, respectively. Gender, sitting postures, and chair and desk designs influenced load distribution patterns significantly.