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U-bar loop connections have traditionally been used to establish structural continuity between wall-elements in precast concrete buildings. However, recent advancements have introduced the looped wire rope connection as a viable alternative due to its installation benefits. While the strength of the connection itself has been investigated thoroughly, the anchoring of the looped wire ropes inside the wall-element remains under-investigated. This paper presents an experimental study including 66 experiments focusing on the anchorage and associated failure mechanisms of looped wire ropes. The experimental study investigates various design parameters such as the embedment length of the looped wire rope, the u-bar in the concrete element, concrete compressive strength, the comparison between an embedded bolt and looped wire rope, and the size of the test specimen, which represents the distance between wire ropes in a wall element and the wall thickness. On the basis of the experimental evidence, a mechanical model is developed based on the principles of rigid plastic modelling. This model key design parameters into account and provides an understanding of the anchorage of looped wire ropes. The model, backed by a detailed analysis of failure mechanisms using digital image correlation, provides an improvement in predicting the anchorage capacity of looped wire ropes in concrete wall elements. • Comprehensive experimental programme on the anchorage capacity of looped wire ropes. • Analysis of failure mechanisms with Digital Image Correlation. • The failure begins as T-shape crack development followed by reinforcement activation. • A rigid plastic model is presented and shows good agreement with failure mechanisms. [ABSTRACT FROM AUTHOR]

Dowel action is a well-known phenomenon in shear-related problems within structural concrete. The tests previously reported in the literature to evaluate this contribution in reinforced concrete beams without shear reinforcement were conducted without any initial activation of the tensile reinforcement. This paper presents the experimental results of dowel tests, performed in a novel experimental test setup. The test setup reflects more realistically the conditions of the tensile reinforcement in reinforced concrete beams without shear reinforcement. The test setup enables a realistic tensile activation of the longitudinal reinforcement before applying the dowel force. The tests show that even a low activation of the tensile reinforcement results in the development of horizontal- and inclined cracks, even before the dowel force is applied. This shows that the contribution from dowel action of the tensile reinforcement is not just simply governed by the splitting strength of the concrete cover. A method to determine the displacement of the dowel from photogrammetric measurements is presented. In addition, a linear elastic- and a rigid-plastic mechanical model are presented for estimating the shear force transferred by the tensile reinforcement in RC beams without shear reinforcement. The estimates are based on measurements of the dowel displacement. Comparison of the presented model and the experimental results shows fairly good agreement. • Presents a novel dowel test setup with a tensile activation of the reinforcement • The tensile activation induces cracks before the dowel force is applied • The shear force carried by dowel action depends on the dowel displacement • An elastic- and a plastic mechanical dowel model is proposed • Comparison of proposed models with the experimental results shows a good agreement [ABSTRACT FROM AUTHOR]

• A novel carbon-efficient 3DCP beam design with a 200% higher strength-to-weight ratio than a full 3D printed beam. • Data-transfer tool from the digital modelling environment to the Finite Element Analysis workspace. • Finite Element Analysis which accurately predicts the capacity and failure mechanism found from structural testing The paper presents a workflow for the design, material testing and numerical simulation of shape-optimised reinforced 3D Concrete Printed (3DCP) beams tested structurally in three-point bending. Building upon previous research on structurally optimised toolpath planning for 3DCP, the presented work suggests a method for the computational design optimisation process based on material efficiency principles and the parallel development of a lossless data transfer tool from the 3D modelling environment to a Finite Element Analysis (FEA) workspace taking into account the layered process characteristic of 3DCP and the consequent weak interactions generated between adjacent printed concrete filaments. The proposed FEA model was calibrated through cored cylindrical specimens and then applied to the design, fabrication and experimental testing of a proof-of-concept shape- and infill-optimised 3-metre simply supported beam. The comparative analysis of simulation and structural testing proves the reliability of the numerical model, which correctly estimated peak load and damage patterns for 3DCP. The tests highlight how, with a shear failure mode, the dominant cracks start from the support region and reach the area of load application. The presented work advances the research in 3DCP by developing 3DLightBeam+, a carbon-efficient reinforced concrete beam design with a 200% higher flexural strength-to-weight ratio than a full comparable beam. The beam is conceived through a seamless workflow for its FE analysis and structural verification that accurately predicts structural capacity and behaviour without destructive testing methods. [ABSTRACT FROM AUTHOR]