Comparative Study on Carbon Emissions and Economics of Three Types of Slab Systems in the Materialization Stages

As one of the most important sources of carbon emissions, the construction industry consumes approximately 30% to 40% of global energy and emits about 30% of global greenhouse gases. Therefore, low-carbon emission reduction in the construction industry is an important means for China to achieve its “3060” strategic goals. In this context, prefabricated buildings have become a development direction for the transformation and upgrading of the construction industry due to their green, low-carbon, and efficient characteristics. Jiangsu Province in China has taken the lead in promoting the application of “three slabs”. Currently, the precast concrete floor slabs in the province mainly use two types: laminated slabs and prestressed hollow slabs. This article takes three types of slab systems (laminated slabs, prestressed hollow slabs, cast in-site slabs) as the research objects, compares and analyzes the construction process of the three in the materialization stage, establishes a calculation model for carbon emissions and comprehensive costs in the materialization stages, and conducts a comparative analysis of carbon emissions and economics from both environmental and economic perspectives. Research has shown that during the materialization stage, cast in-site slabs have the highest carbon emissions per unit area, with an increase of approximately 71.3% and 74.3% compared to laminated slabs and prestressed hollow slabs, respectively. The highest construction and installation cost per unit area is also for cast in-site slabs, which are increased by about 113.8% and 64.9%, respectively, compared to laminated slabs and prestressed hollow slabs. Among them, material costs are the most significant factor affecting construction and installation costs. The comprehensive cost per unit area of cast in-site slabs is much higher than that of laminated slabs and prestressed hollow slabs, with the construction and installation costs being the most important factors affecting the comprehensive cost. Therefore, compared with cast in-site slabs, laminated slabs and prestressed hollow slabs have significant advantages in carbon emissions and economics and thus have practical significance for carbon reduction in the construction industry and are worth promoting and further developing.