Predicting the response of continuous RC deep beams under varying levels of differential settlement

This paper investigates the effect of differential support settlement on shear strength and behavior of continuous reinforced concrete(RC)deep beams.A total of twenty three-dimensional nonlinear finite element models were developed taking into account various constitutive laws for concrete material in compression(crushing)and tension(cracking),steel plasticity(i.e.,yielding and strain hardening),bond-slip at the concrete and steel reinforcement interface as well as unique behavior of spring-like support elements.These models are first validated by comparing numerical predictions in terms of load-deflection response,crack propagation,reaction distribution,and failure mode against that of measured experimental data reported in literature.Once the developed models were successfully validated,a parametric study was designed and performed.This parametric study examined number of critical parameters such as ratio and spacing of the longitudinal and vertical reinforcement,compressive and tensile strength of concrete,as well as degree(stiffness)and location of support stiffness to induce varying levels of differential settlement.This study also aims at presenting a numerical approach using finite element simulation,supplemented with coherent assumptions,such that engineers,practitioners,and researchers can carry out simple,but yet effective and realistic analysis of RC structural members undergoing differential settlements due to variety of load actions.

Fire hazard in transportation infrastructure:Review,assessment,and mitigation strategies

This paper reviews the fire problem in critical transportation infrastructures such as bridges and tunnels.The magnitude of the fire problem is illustrated,and the recent increase in fire problems in bridges and tunnels is highlighted.Recent research undertaken to address fire problems in transportation structures is reviewed,as well as critical factors governing the performance of those structures.Furthermore,key strategies recommended for mitigating fire hazards in bridges and tunnels are presented,and their applicability to practical situations is demonstrated through a practical case study.Furthermore,research needs and emerging trends for enhancing the“state-of-the-art”in this area are discussed.

Causality in structural engineering: discovering new knowledge by tying induction and deduction via mapping functions and explainable artificial intelligence

Causality is the science of cause and effect.It is through causality that explanations can be derived,theories can be formed,and new knowledge can be discovered.This paper presents a modern look into establishing causality within structural engineering systems.In this pursuit,this paper starts with a gentle introduction to causality.Then,this paper pivots to contrast commonly adopted methods for inferring causes and effects,i.e.,induction(empiricism)and deduc-tion(rationalism),and outlines how these methods continue to shape our structural engineering philosophy and,by extension,our domain.The bulk of this paper is dedicated to establishing an approach and criteria to tie principles of induction and deduction to derive causal laws(i.e.,mapping functions)through explainable artificial intelligence(XAI)capable of describing new knowledge pertaining to structural engineering phenomena.The proposed approach and criteria are then examined via a case study.