Green building rating systems are developed to promote sustainability. Existing rating systems use both numerical and linguistic descriptors. In addition, existing rating systems do not directly identify the priority or interrelation between different parameters. The objectives of this study are to develop a priority weights-based green building rating model with numerical descriptors and to propose a remediation plan for existing buildings to obtain green certification under the developed rating model. In this paper, the analytical hierarchy process is used to develop a green building rating system. Based on the opinions of 100 experts, the priority weights of parameters were determined. The numerical thresholds of point allocation, equations, and priority weights of the proposed rating model supports a definitive classification on green building performance. For buildings with poor green performance, a remediation plan is proposed that can be adopted to upgrade and obtain green certification for buildings under the developed rating model.

Developments in nanomaterial technology have generated a strong research interest in the construction industry aiming at enhancing the properties of concrete. Many studies have explored the use of engineered nanomaterial such as nano-silica, carbon nanotubes (CNT) and nanofibers in cementitious composites. Recently, nanomaterial studies have focused on Graphene and Graphene Oxide (GO). Graphene is the single atomic layer thick two-dimensional form of graphite and GO is the oxidized form of graphene which is synthesized by oxidation of graphite. Investigations have demonstrated that the use of GO in cementitious composites can enhance their performance. This paper outlines the development of a high-performance graphene-based concrete. Moreover, the paper presents a brief review of previous studies conducted on GO induced cementitious composites and remarkable performance enhancement enabled by GO. The findings of this study contribute towards establishing how GO can be adopted as a nanomaterial additive for concrete.

This study presents a detailed and comprehensive investigation into the macro-scale performance, strength gain mechanisms, environment and economic performance of graphene oxide (GO)-enhanced low-emission concrete. A comprehensive experimental program evaluated fresh and hardened properties, including slump retention, bleeding, air content, compressive, flexural, and tensile strength, drying shrinkage, and elastic modulus. Scanning Electron Microscopy (SEM), energy-dispersive spectroscopy (EDS), Thermogravimetric analysis (TGA) and proton nuclear magnetic resonance (¹H-NMR) was employed to examine microstructural evolution and early age water retention, confirming GO’s role in accelerating cement hydration and promoting C-S-H formation. Optimal performance was achieved at 0.05% GO (by binder weight), resulting in a 25% increase in 28-day compressive strength without compromising workability. This outcome is attributed to a tailored, non-invasive mixing strategy, wherein GO was pre-dispersed during synthesis and subsequently blended without the use of invasive mixing methods such as high shear mixing or ultrasonication. Fourier-transform infrared (FTIR) spectroscopy further validated the chemical compatibility of GO and PCE and confirmed the compatibility and efficiency of the admixture. Sustainability metrics, including embodied carbon and strength-normalized cost indices (USD/MPa), indicated that, although GO increased material cost, the overall cost-performance ratio remained competitive at breakeven GO prices. Enhanced efficiency also led to lower net embodied CO₂ emissions. By integrating mechanical, microstructural, and environmental analyses, this study demonstrates GO’s multifunctional benefits and provides a robust basis for its industrial implementation in sustainable infrastructure.

For rural bridges in Australia, a common design practice is pouring in-situ concrete on top of beams in order to tie all the beams together and distribute load. However, pouring concrete on-site creates more risk and contractors prefer to avoid it. Another method is using transverse post tensioning to tie beams. This article investigated the behaviour of transverse post-tensioning bars in providing load distribution between beams and ultimately comment on their effectiveness compared to in-situ poured decks. Currently, the industry has not completely investigated this matter in order to design post-tensioning accurately. Conservative estimates are currently used in industry today. Current practice is 50% of the design load on the beam where the load is applied in their design assumptions which is quite high. The team modelled concrete box girder bridges with transverse post-tensioning using grillage method. Several factors were investigated including bridge length and width, bridge skew and beam type. From the models, the team concluded that increasing the bridge span increases the load distribution, the load distribution difference is negligible for skew between 0 and 20 degrees and larger shear actions are observed with increased skew and width. It was determined that the worst-case total load on the beam where the load as applied was found to be 40.5%, 9.5% less than current practice. It is recommended that a similar investigation is conducted using a finite element method to gain a deeper understanding.