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As the global economy moves towards a sustainable and circular trajectory, the immense role of the construction industry is becoming increasingly apparent as one of the most waste-intensive sectors. Urban mining and subsequent material reuse or recycling are the recommended remedies to lower resource extraction and waste generation in the upcoming decades.This article looks at the recycling practices and offers a solution to revalorise construction recyclables, regulate the isolated recycling activities and incentivise construction material manufacturers to take responsibility for recycling their own products after their lifecycle is over. Consequently, the future volumes of recyclables will become calculable and transparent, which balances the supply and demand of secondary materials. To this end, this study goes beyond manufacturing traceability and investigates manufacturer traceability. Material banks, Building Information Models, blockchain technology and smart contracts are used to conceptualise a novel business model for highly recyclable construction materials. On the one hand, the value of recyclables is captured through salvage value based on accounting methods. Smart contracts administer the physical material transfer for recycling while automating the monetary value transactions between stakeholders. On the other hand, a financial instrument is proposed to link the on-chain captured value to the off-chain financial practices through the Recycling Requirement Rights. The right holders are responsible for recycling; they could be the material manufacturers or not. The discussions on the threats and opportunities as well as weaknesses and strengths of the proposed framework together with its potential to integrate with existing solutions conclude this study.

A novel damage detection and localisation method, the so-called Deformation Area Difference method for localisation of damages in bridge structures is introduced. The method is based on static load-deflection experiments with the prerequisite of high precise deflection measurement. This study presents the first experiences of applying the DAD method on a real bridge structure. The investigated structure is a prestressed concrete slab bridge with a span of about 27 m, which was built in 2013. The loading on the bridge is applied using six heavy trucks, each weighing up to 32 t. A wide range of the modern measurement technologies were used to achieve high precision measurements of the bridge deflection along the longitudinal axis, namely the photogrammetry using a big size drone, laser scanner, total station, levelling and displacement sensors. The performed load-deflection test was non-destructive since the maximum deformation did not exceed the serviceability limit state. The exercise of the novel damage detection and localisation method on a real structure initiated further optimisation opportunities of the DAD method and the study of its limits. Several boundary conditions and methodical influence factors related to the applicability of the proposed method were analysed, such as impacts of measurement precision, damage degree, the position of damage, and the number of measurement repetitions.

In this paper, Miscanthus fibres are used to develop lightweight concrete. The amount of Miscanthus and cement, as well as the water/cement ratio, are varied to analyse the behaviour of the mixture concerning the physical and mechanical properties. The Miscanthus was pre-treated with a silicate sealant or a cement-based fluid. The current paper analyses the impact of the pre-treatment of the Miscanthus fibres on the compressive strength as well as on the long-term deformations. The specimens with a pre-treatment based on a silicate sealant reached a compressive strength of 19.3 MPa, which is higher than the compressive strength of a conventional LC 16/18, a Young's Modulus above 9.9 GPa and a shrinkage deformation of 2244 μm/m. Nevertheless, considering the density the pre-treatment showed not to be beneficial.

The construction industry consumes an enormous amount of global resources and produces more waste than any other sector. The need to move toward sustainable development in construction requires significant changes in construction and demolition (C&D) waste management. The estimation of waste, recycling materials and reusable components could be vital in waste management, achieving huge efficiency in the construction industry. Moreover, a typical building comprises of an extensive amount of materials and components with various characteristics. This study proposes a Building Information Modelling (BIM) based system to allow the circular economy by storing information of the materials and components of buildings and by effectively managing the recycling of materials and reuse of components. A tool which serves as Material and Component (M&C) bank is developed with PHP and MYSQL by making use of a web browser able to extract the materials and component information of a building through the BIM model. This information is vital for several uses such as quantification of C&D waste and assessing for the design for deconstruction. It can also be used to obtain the information of reusable condition of the components and instructions for the reconstruction.

Pile punching (or driving) affects the surrounding area where piles and the adjacent piles can be displaced out of their original positions due to horizontal loads, leading to hazardous outcomes. This paper presents a 3D coupled Smoothed Particle Hydrodynamics and Finite. Element Method (SPH-FEM) model, which was established to investigate pile punching and its impact on adjacent piles subjected to lateral loads. This approach handles the large distortions by avoiding mesh tangling and remeshing, contributing greatly high computational efficiency. The SPH-FEM model was validated against field measurements. Results of this study indicated that the soil type in which piles were embedded affected the interaction between piles during the pile punching. A comprehensive parametric study was carried out to evaluate the impact of soil properties on the displacement of piles due to the punching of an adjacent pile. It was found that the interaction between piles was comparatively weak when the piles were driven in stiff clays; while the pile-soil interactions were much more significant in sandy soils and soft clays.

In this paper, a new computational approach, which is based on a multi-physics coupling of the chemo-thermo-mechanical process, is developed for modeling failure mechanism in cement-based materials at early-age hydration. A new constitutive law describing mechanical behavior of young concrete is thus derived, taking into account the effects of several factors including thermal expansion, shrinkage, damage, and both basic and transient thermal creeps. A strongly coupled model describing the interaction between fracture and multi-physics problems of cement hydration is obtained. The present phase field model in terms of smeared crack approach is highly suitable for simulating crack, especially when considering the unilateral contact conditions at crack surfaces. The capability of the proposed model in modeling complex crack initiation and propagation under arbitrary boundary conditions is highlighted. Fracture phenomena at both macroscopic and mesoscopic scales are considered and analyzed. The effects of creep and microstructural heterogeneity in different length scale are investigated, showing the great potential of the developed approach.