The Carbon Emission Assessment of a Building with Different Prefabrication Rates in the Construction Stage

Abstract

The utilization of prefabricated components is taken as a potential way to reduce carbon emissions from the construction industry, and the prefabrication rate may be a factor that influences the mitigation efficiency. This study develops an assessment method to compare carbon emissions of a building in the construction stage when it is built with multiple different prefabrication rates. Firstly, two carbon sources (building materials and machineries) and three construction sub-phases (production of materials and components, transportation, and on site construction) are determined to clarify the calculation boundary. Then, a carbon emission measurement model for prefabricated buildings in the construction stage is developed by using a process-based method. A dormitory building in Chongqing, China, is selected to conduct a case study to show the application of the provided model. The result shows that the carbon emission of prefabricated buildings is higher compared to that of traditional cast-in situ buildings. Moreover, the emission of prefabricated buildings decreased slightly with the increase in the prefabrication rate. A detailed discussion is followed to investigate the reason why the carbon emission does not decrease with the utilization of prefabricated units. Based on the discussion, some suggestions are given to improve the carbon emission reduction efficiency of prefabrication techniques.

A Robotic Solution for Precision Smoothing and Roughening of Precast Concrete Surfaces: Design and Experimental Validation

“…Figure 10e shows the full-coverage path map for the smoothing operation, where light gray represents reserved holes and dark gray represents protruding embedded components. When passing through the embedded pipe at coordinate (21,4), the BINN algorithm reveals that the activity values of surrounding neurons are less than those at the current location, causing the algorithm to enter a deadlock. By recalculating using the A* algorithm, the deadlock is successfully escaped.…”

Technological and Sustainable Perception on the Advancements of Prefabrication in Construction Industry

“…However, prefab constructions were proved to consume less energy, produce less wastage, and emit fewer emissions when compared to conventional methods during the construction and end-of-life stages [42,66]. The carbon emissions are further discerned to decrease with the increase in the prefabrication rate [70]. The concept of netzero energy building (nZEB) also includes prefab elements whose ultimate aim is to create an energy-efficient building where net energy flowing to/from a building sums to zero [69].…”

Evolutionary Analysis of Prefabrication Implementation in Construction Projects under Low-Carbon Policies

“…In prefabrication, building components are manufactured in factories and transported to the construction site for installation. This approach improves construction efficiency and quality, and reduces labour requirements and resource consumption [8][9][10][11][12][13][14][15][16]. Teng et al [17] found that prefabricated buildings achieved an average of 15.6% embodied carbon reduction and 3.2% operational carbon reduction compared to conventional buildings.…”