Systematic Analysis of Production Errors and Accuracy when using Pin-Bed Mold of Free-form Concrete Panels

Abstract

Although various mold design and techniques have been introduced for free-form building production, successes so far have been only minor owing to lack of adaptability, machine errors, and high production cost. Herein, this presents a new reusable mold technique called a Pin-bed Mold (PBM), an inexpensive rubber mold based mechanical method and validates its applicability using the shape implementation method. This paper also describes a Failure Mode Effects Analysis (FMEA) for development of the PBM considering risk. A prototype free-form shape was designed using Computer-aided Design (CAD), and an experiment was conducted to produce smooth Free-form Concrete Panels (FCPs) rapidly and easily using a Computerized Numerical Control (CNC) machine and PBM. The rubber mold produced was measured using an optical sensor and compared with the designed FCP shape. The experimental showed significant errors in FCP shape between the CAD design and the measured CNC, and PBM shapes. The failure modes of the PBM and their causes were identified, while examining the PBM production capability. According to the FMEA method, weaknesses in the operation of PBM that could potentially lead to shape errors were identified.