Construction Worker and Equipment Energy Consumption for Offsite Precast Concrete

Abstract

The concept of construction industrialization was first introduced during the 1960s. Previous studies define construction industrialization as moving onsite construction work to offsite factories, largely depending on the assistance of automated machines and equipment. In some developing countries, industrialization of construction projects is highly recommended to minimize construction waste and pollution. However, no formal method has been developed to calculate the industrialization rate of construction projects. The overall goal of this study was to develop such a method. To this end, the authors utilize energy expenditure as a basis for assessing industrialization rate. Previous research has investigated the energy expended by construction workers when performing onsite activities. To determine the differences between on-site and offsite processes in terms of energy expenditure, the present study focuses on offsite construction processes and the related energy expenditure. The findings provide input to create a quantification model of the construction process. To collect accurate and persuasive data, survey and site-observation research methods were utilized. The authors chose the overall concrete construction process as the main focus for the study, and conducted a survey of precast concrete plant personnel and observed precast concrete plant operations in the Pacific Northwest. Based on the data analysis, the physical activity level of offsite precast concrete processes was quantified as 2.51, which is within the comfort zone for human work. In addition, with newly defined levels of automation (LOAs), the authors developed correlations between the LOAs and the ratios of power to plant size, production, and expenditure, respectively. The findings from this study provide foundational knowledge needed to develop a method to quantify the industrialization rate of construction projects. With such a method available, project stakeholders can make sound decisions based on the extent of construction industrialization and associated benefits.