Novel bendable concrete tactile for footpath application

• Main Author: Lim, Zhi Jie
• Other Authors: En-Hua Yang
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2022
• Subjects: Engineering::Civil engineering
• Online Access: https://hdl.handle.net/10356/163835
• Institution: Nanyang Technological University

LTA has received public feedback regarding the slipping hazard that current tactile tiles pose. This paper presents a novel approach replacing the current ceramic material with bendable concrete, also known as Engineered cementitious composite (ECC). ECC are a special class of High-Performance Fibre Reinforced Cementitious Composites, exhibiting desirable mechanical properties such as excellent tensile ductility and damage tolerance. Performance requirement of the tiles such as skid resistance, colour contrast and mechanical strength testing was established. Sample formulation of the ECC tactile was done in three stages - to satisfy performance requirement, followed by mix design optimization and lastly tile fabrication for test-bedding. Experiments on skid resistance, water absorption and modulus of rupture were tested to validate the performance of ECC specimens to meet requirements. Moreover, compressive strength and tensile strain capacity were conducted to ascertain the specimens were within the acceptable range of typical ECC limits. Different mix proportions of slag/cement, fly ash/cement, fibre content, fibre length and pigment content were prepared for ECC specimens under the same curing conditions. From mix optimization, the optimum mix consisting slag/cement ratio of 2.0 and 1.4% Fibre content of the mix volume, delivered adequate mechanical properties for future mass production. Experimental results indicated ECC specimen tested 44.9 MPa in compressive strength and 4% in tensile strain capacity. Various techniques to satisfy the performance recruitment, namely sandblasting of the tactile mould and polishing were investigated to improve skid resistance. Both techniques formed a positive relationship with the skid resistance.