Research on the Application of Prefabricated Pavement Slabs in Non-Conventional Natural Gas Drilling Projects

Abstract

In recent years, traditional cast-in-place concrete construction for pre-drilling engineering in unconventional natural gas fields has generated large amounts of waste concrete, consumed significant resources, and prolonged project schedules. To address these issues, this study proposes a prefabricated pavement slab system as a green and low-carbon alternative. Based on vehicle load surveys at shale-gas well sites in southwestern China, three loading conditions (design, overload, and ultimate axle loads) were defined. Theoretical calculations were then performed for reinforcement design, crack-width control, and local bearing capacity verification. A full-scale precast slab (3000 × 1495 × 150 mm) was fabricated and tested under static monotonic loading to measure deflection, crack development, steel strain, and concrete strain until failure. Separately, a three-dimensional finite element model of a four-panel pavement system (including a mortar-leveling layer and soil subgrade) was developed in ANSYS to simulate static and, preliminarily, moving loads. The experimental slab reached an ultimate load of about 365 kN (based on a single specimen, and thus not statistically representative), with ductile bending failure and crack/deflection patterns typical of reinforced concrete. The numerical model reproduced the cracking load and peak capacity with deviations below 17% from the test data, though post-cracking deflections were underestimated. Overall, the results demonstrate that the proposed prefabricated system is structurally feasible for heavy-duty drilling sites. It enables factory production, rapid on-site assembly, and reuse after dismantling, thereby reducing construction waste, shortening timelines, and supporting energy conservation and emission-reduction goals in the context of China’s green building policies.