A Structured Continuous Improvement Process for High-rise Construction Using Time-motion Studies

This research investigates the implementation of a pragmatic continuous improvement process following a PDCA (Plan-Do-Check-Act) cycle within a large Mexican construction company specializing in post-tensioned concrete for high-rise buildings. Over a 2.5-year period and across 13 active projects ranging from 20 to 50 stories, the company aimed to optimize slab construction cycles, a critical and repetitive element impacting project duration and cost. To bridge the gap between field-level innovation and organizational implementation, this research presented a structured four-step PDCA approach: Step 1 - Plan: Time-motion study review and collaborative brainstorming; Step 2 - Do: Controlled trial implementation; Step 3 – Check: Data collection and evaluation; and Step 4 – Act: Standardization via A3. Over 200 time-motion studies, primarily on rebar and formwork (97%), provided data-driven insights that led to the development of 205 improvement initiatives, with 175 approved for trial implementation. Among these, 88 % targeted time, cost, and quality improvements. While the PDCA process proved effective in driving operational efficiency, challenges persist in sustaining momentum, enhancing communication channels, and reducing reliance on manual data processing. This study highlights the role of a structured bottom-up approach in integrating field-level innovation into long-term organizational improvements in construction projects.