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This article discusses the importance of reproducibility in academic research, specifically in the field of bridge engineering. The authors argue that reproducibility is challenging due to factors such as paper documentation, technology constraints, and proprietary issues. They propose implementing a policy that encourages researchers to make their data and models available to others, although they acknowledge that full reproducibility may not always be practical. To incentivize this practice, the Journal of Bridge Engineering plans to introduce a visible recognition badge for papers that provide open data, models, and codes. The authors also outline the review process for papers seeking the "Data Verified Paper" designation. [Extracted from the article]

The Journal of Hydrologic Engineering is a major journal in the field of hydrologic science and engineering. It has been published for 27 years and covers a wide range of topics related to hydrology and water resources. The journal recently revised its aims and scope to reflect changes in the field, including advancements in technology and emerging areas of study. The journal publishes various types of papers, including technical papers, case studies, and state-of-the-art reviews. The review process is efficient and fair, with a typical turnaround time of 2 months. The journal encourages researchers to submit their work and also invites them to serve as reviewers. Additionally, the journal publishes special collections and offers opportunities for young professionals to join the Early Career Editorial Board. [Extracted from the article]

The current construction industry for civil and structural engineering is considered to be one of the growing industries in the world. With the push toward a more digitized industry, emerging trends such as additive manufacturing and the use of three-dimensional (3D) printing technology, along with consumer demand, are resulting in automated development with multiple benefits. Successful applications for small-scale construction projects that have implemented 3D printing have shown improvements in cost, production time, and design freedom and complexity. However, for large-scale applications, there are various limitations and factors hindering the adoption of additive manufacturing technologies. In this paper, a systematic literature survey of recent 3D printing technologies was conducted specific to the area of construction engineering, and the various techniques, materials, software, and technical and nontechnical aspects were analyzed. The key applications and their benefits are outlined, and their potential for large-scale applications is articulated. Future research areas for these components are suggested to strengthen the technical readiness and feasibility of adopting 3D printing technology in construction engineering and industries. [ABSTRACT FROM AUTHOR]

Forum papers are thought-provoking opinion pieces or essays founded in fact, sometimes containing speculation, on a civil engineering topic of general interest and relevance to the readership of the journal. The views expressed in this Forum article do not necessarily reflect the views of ASCE or the Editorial Board of the journal. [ABSTRACT FROM AUTHOR]

The traditional approach to formulating building codes often is slow and labor-intensive, and may struggle to keep pace with the rapid evolution of technology and domain findings. Overcoming such challenges necessitates a methodology that streamlines the modernization of codal provisions. This paper proposes a machine learning (ML) approach to append a variety of codal provisions, including those of empirical, statistical, and theoretical natures. In this approach, a codal provision (i.e., equation) is analyzed to trace its properties (e.g., engineering intuition and causal logic). Then a ML model is tailored to preserve the same properties and satisfy a collection of similarity and performance measures until declared equivalent to the provision at hand. The resulting ML model harnesses the predictive capabilities of ML while arriving at predictions similar to the codal provision used to train the ML model, and hence it becomes possible to use in lieu of the codal expression. This approach was examined successfully for seven structural engineering phenomena contained within various building codes, including those in North America and Australia. The findings suggest that the proposed approach could lay the groundwork for implementing ML in the development of future building codes. [ABSTRACT FROM AUTHOR]

In the era of automation and artificial intelligence, some problems in the petroleum industry can be efficiently solved by machine-learning models based on big data. Previous researchers have addressed truly precise methods to evaluate reserves from accessible well-test data, although enormous time, effort, and cost were required. However, due to the lack of sufficient conventional material balance (CMB) test data for a large number of wells in the Su Dong (SD) gas field, only 12 wells (0.99%) were generally suitable for previous methods. We substituted the fully built-up reservoir pressures used in CMB with those converted from shut-in casing-pressure data. Suffering from data noise caused by pressure fluctuation, only 22.91% of the plots were linear. The nonlinear plots were enhanced into linear plots by denoising and smoothening according to engineering knowledge. Machine-learning models were developed to perform the enhancement automatically, which constructed an adaptive and feasible workflow. The model improved the percentage of applicable wells to 68.16% (824 out of 1,209) and achieved considerable precision for reserve evaluation. The proposed method is much more suitable than CMB in gas fields featuring unstable production status and provides feasible reserve evaluation. This paper presents an exemplary demonstration of the combination of petroleum engineering and machine learning. [ABSTRACT FROM AUTHOR]

As emerging high-performance concrete, the engineered cementitious composite (ECC) has demonstrated excellent application potential in civil engineering. With the wide application of ECC, it not only excels in the tension state and the structural elements but also in the more complex stress state of nonuniform confinement. For a reliable and economic ECC element design, understanding the dilation behavior of ECC is crucial under complicated stress conditions. This paper presents an experimental investigation and a detailed discussion of the ECC dilation characteristics under different confinement rigidities. The authors evaluate the effects of column parameters, such as different types of fiber-reinforced polymer (FRP) composites, confinement levels, and cross-sectional shapes. Test results indicate that the ECC dilation amplitude (secant dilation) under FRP confinement is less than that of concrete due to fiber bridge effects within ECC. However, the maximum dilation rate (tangent dilation ratio) shows an opposite trend. Based on the data analysis in this study, a new lateral strain-to-axial strain model was proposed, which can predict the dilation behavior of FRP-confined ECC with nonuniform confining pressure. The proposed model not only accurately captures the dilation process of FRP-confined ECC but also precisely predicts its ultimate strain. In addition, the existing peak strength and ultimate strength models were also evaluated by the ECC test results. The comparison indicates that the strength models for concrete also apply to FRP-confined ECC when the ultimate hoop-confining stress is accurately determined. [ABSTRACT FROM AUTHOR]

As inelastic design for wind is embraced by the engineering community, there is an increasing demand for computational tools that enable the investigation of the nonlinear behavior of wind-excited structures and subsequent development of performance criteria. To address this need, a probabilistic collapse assessment framework for steel structures is proposed in this paper. The framework is based on the integration of a high-fidelity fiber-based nonlinear structural modeling environment with a wind-tunnel-informed stochastic wind load model to perform nonlinear time history analysis. General uncertainty is propagated using a stratified sampling scheme enabling the efficient estimation of reliabilities associated with rare events. The adopted models for simulating high-fidelity nonlinear structural behavior were found, in general, to be adequate for capturing phenomena, including progressive yielding, buckling, and low-cycle fatigue, that are essential for wind induced collapse analysis. In particular, the adopted fatigue model was found to be capable of predicting damage and potential fiber/section fracture associated with non–fully reversing stress-strain cycles that are characteristic of wind loading. Through illustration on a 45-story archetype steel building, critical discussions on the types of observed collapse mechanisms, the difference between along-wind and across-wind nonlinear behavior, reliabilities associated with first yield, and collapse are presented. A probabilistic description of the residual and peak story drifts is also provided through development of fragility functions. [ABSTRACT FROM AUTHOR]

Geopolymers have been long recognized as the next-generation building material due to environmental reasons. However, geopolymers are inherently brittle and usually require high-temperature curing. This paper was intended to develop a ductile engineered geopolymer composite (EGC) under ambient curing conditions. Two types of metakaolin powder with different particle sizes were applied as the solid precursor. The tensile, compressive, and flexural behaviors of EGC with different mix designs were investigated. It was concluded that the combinational application of coarse and fine metakaolin is conducive to the tensile and compressive behaviors of EGC materials. As the alkali concentrations increased from 6 to 14 mol/L , the tensile and compressive strength of EGC increased, whereas the tensile ductility of EGC decreased gradually. Also, the SiO2/Na2O molar ratio had negligible influence on the tensile behavior of EGC, whereas the compressive strength decreased with the increase of SiO2/Na2O molar ratios. A numerical model to predict the flexural behavior of EGC was also proposed, and the accuracy was verified with experimental results. [ABSTRACT FROM AUTHOR]

Although there have been several studies about using recycled aggregates to construct recycled aggregate base (RAB) layers, there is a lack of information about the effects of gradation of recycled concrete aggregate (RCA) materials on the performance of such layers. There is also limited information available regarding the use of RCA and recycled asphalt pavement (RAP) materials together in RAB layers. In this study, three test cells were constructed with RAB layers using two different RCA materials with different gradations and a blend of RCA and RAP materials, and another cell was constructed with a natural aggregate base layer. Physical characteristics of the base layer aggregates were determined, and resilient modulus (MR) tests were performed. A series of falling weight deflectometer (FWD) tests were performed in the field, and changes in air and soil temperatures over time were monitored. This paper contains detailed information about the evaluation of the engineering properties of recycled aggregates and the preliminary performance of the constructed RAB layers. [ABSTRACT FROM AUTHOR]

This paper presents the results from a prediction event, organized by the University of Western Australia (UWA) and the National Geotechnical Centrifuge Facility (NGCF), and performed as part of the International Symposium on Frontiers in Offshore Geotechnics to assess uncertainty in predicting the monotonic and cyclic lateral response of conductors. Geotechnical professionals from around the world were invited to predict the response of a model conductor (a flexible pile) subjected to a series of loading sequences in a centrifuge. A normally consolidated fine-grained soil was used in the tests, which was characterized by soil elements and in-flight T-bar penetrometer testing. While some participants provided accurate predictions, the mean response was an overestimate of the monotonic and cyclic load at the pile head, which was significant for large and very small displacements. An analysis of the submissions is presented to quantify the variability of the predictions received, assess the consequences of each design, and relay the uncertainty associated with engineering judgment in design. [ABSTRACT FROM AUTHOR]

This paper presents the findings from a study of the breakdown of project success criteria. An exploration of the evolution of studies on the success of engineering projects over decades was the basis for a project success definition proposal. Using a comprehensive literature review of success criteria for engineering projects, a list of 133 different success criteria was identified. Those criteria were analyzed to develop an integrated framework of project success criteria, describing its hierarchical decomposition. Such a breakdown structure could serve as a starting point when setting project success criteria for a specific project, because the importance of criteria will be context dependent. Practitioners or stakeholders could discuss and tailor it based on specific features of engineering projects or specific needs and interests. Generally, criteria have evolved from simple work-related factors to focusing more on the complex benefits of the projects. Such an evolving success definition has implications for further studies of project success and might contribute toward a long-term vision in which all projects will be delivered successfully. [ABSTRACT FROM AUTHOR]

Funicular geometries, which follow the idealized shapes of hanging chains under a given loading, are recognized as materially efficient structural solutions because they exhibit no bending under design loading, usually self-weight. However, there are circumstances in which nonstructural conditions make a funicular geometry difficult or impossible. This paper presents a new design philosophy, based on graphic statics, that shows how bending moments in a nonfunicular two-dimensional curved geometry can be eliminated by adding forces through an external posttensioning system. An interactive parametric tool is introduced for finding the layout of a posttensioning tendon for any structural geometry. The effectiveness of this approach is shown with several new design proposals. [ABSTRACT FROM AUTHOR]

One key issue in the simulation of bare electrodynamic tethers (EDTs) is the accurate and fast computation of the collected current, an ambient dependent operation necessary to determine the Lorentz force for each time step. This paper introduces a novel semianalytical solution that allows researchers to compute the current distribution along the tether efficient and effectively under orbital-motion-limited (OML) and beyond OML conditions, i.e., if tether radius is greater than a certain ambient dependent threshold. The method reduces the original boundary value problem to a couple of nonlinear equations. If certain dimensionless variables are used, the beyond OML effect just makes the tether characteristic length L* larger and it is decoupled from the current determination problem. Avalidation of the results and a comparison of the performance in terms of the time consumed is provided, with respect to a previous ad hoc solution and a conventional shooting method. [ABSTRACT FROM AUTHOR]

Drilling is a material removal process that introduces the plastic deformation and stresses around the hole. When large amounts of drilling stresses are added up, there will be deformation in the aerostructural assembly. This paper presents an aerostructural assembly deformation predicting method considering drilling-induced stresses around the riveting hole. Drilling-induced stresses are simulated with additional temperature fields. The assembly of the two riveted plates are considered to illustrate effects of drilling-induced stresses coupling and validate the proposed model. The simulation and experimental results show that one hole's drilling-induced stresses have negligible impact on the riveting deformation, while a lot of holes' drilling-induced stresses must be considered in assembling. When a lot of drillinginduced stresses are added up, there will be significant deformation in the aircraft's structure. The deformation predicting method outlined in this paper will enhance the understanding of the compliant components deformation resulting from the drilling stresses and help systematically improve the precision control efficiency in the civil aircraft industry. [ABSTRACT FROM AUTHOR]

Link-to-column connections in steel eccentrically braced frames must be capable of sustaining large cyclic forces and inelastic rotations. United States code provisions require that satisfactory performance of link-to-column connections be verified by testing under a prescribed loading protocol. However, there are few link-to-column connection details that have satisfied these testing criteria. This paper describes a pilot investigation of two promising link-to-column connection details, as follows: (1) the fillet welded connection, which uses fillet welds or a combination of fillet and groove welds between the link and the column flange; and (2) the supplemental web doubler connection, which reinforces the connection region using a pair of doubler plates in the first link web panel next to the column, parallel to but offset from the link web. These two details showed excellent performance in a series of eight tests. This paper describes these link-tocolumn connection details, summarizes the results of cyclic loading tests, and discusses design issues and approaches for these connections. [ABSTRACT FROM AUTHOR]

A key underlying challenge in today's model-driven approach to engineering is how progress and level of effort are being measured and reported. Recent definitions such as level of development enable project teams to track completeness of information in building information modeling (BIM)-driven processes; yet, there are no established processes or metrics to reliably measure progress or track productivity of a model-driven engineering process as a function of the maturity of the model and/or the data that supports the engineering process. To address this gap in knowledge, this paper presents a discrete set of model maturity index (MMI) definitions to measure progress in engineering work, per modeling discipline. Using these MMI definitions, a model maturity risk index (Model MRI) toolkit was created to track maturity of an engineering process at the granularity of work breakdown structure locations. The MMI toolkit also reports risk in achieving certain MMI levels per modeling discipline. To benchmark maturity of the modeling work per project milestone or model review session and to establish workflows for tracking progress, an addendum to the modeling execution plan (ModelXP) is presented. New productivity and project controls metrics for tracking modeling work are also introduced. The developed definitions, toolkit, and addendum to ModelXP were validated through exhaustive surveys and charrette tests with project stakeholders involved in capital projects. The role of the MMI definitions and Model MRI toolkit in providing project controls insight and proactive management opportunities in real-world projects is discussed in detail. [ABSTRACT FROM AUTHOR]

This paper contains a summary of the developments and applications of the two-dimensional discontinuous deformation analysis (DDA2D) method regarding the modeling of rock-mass dynamics problems. Reviews on the control parameter value selections in DDA2D calculations and the developments and applications of the DDA2D regarding the analysis of rock slope failures, landslides, rockfall, some earthquake-related problems, and so forth, are performed. Research on the DDA2D for three basic rock-mass dynamics problems, such as block dynamic sliding, stress wave propagation, and dynamic fracturing, are specially stated. The modeling of rock blasting, a typical exact rock dynamics problem, is selected as a representative application example of the DDA method to be presented. Generally, the DDA2D has shown to be a powerful numerical method for the modeling of rock-mass dynamics. However, one should pay enough attention to the value selections of those important user-supplied control parameters, as well as to other important factors, such as block size and boundary conditions, for rock dynamics simulations, which have been specially addressed in the paper. [ABSTRACT FROM AUTHOR]

Recently, formal approaches to interface management (IM) have been adopted in a number of large-scale engineering and construction (E&C) projects. However, understanding of the role and performance of IM practices in E&C projects is quite limited today. Given this circumstance, this paper attempts to understand the effectiveness of IM practices in E&C projects from the perspective of dealing with project complexity. To fulfill the objective, data on project complexity and IM practices were collected from 45 large-scale E&C projects and analyzed using quantitative analysis methods such as principal component analysis and linear regression. The data analysis revealed that current formal IM practices employed in E&C projects are effective for mitigating the adverse impact of project complexity originating from uncertainty in scope and communication and large numbers of stakeholders; however, they are not as effective for dealing with project complexity originating from large numbers of engineered items. These results provide insights into the direction of future advancement in IM techniques for large-scale E&C projects. [ABSTRACT FROM AUTHOR]

Systems of second-order linear ordinary differential equations (ODEs) to arbitrary input functions appear in many fields of physics and engineering. Numerical methods for solving these kinds of problems have been mainly performed in the time and frequency domains. In contrast, this paper develops an efficient, seminumerical pole-residue method implemented in the Laplace domain. In this article, a key concept and development is on how to compute the poles and residues of the output from those of the input and system transfer functions. Once the poles and residues of the output are known, the corresponding time history of the output is readily obtained. Even though the correctness of the new method has been verified by using a step-by-step time-domain solution, the accuracy of the new method in theory is higher than that of any time-domain approach, partially because the output obtained from the new method is a continuous function of time. [ABSTRACT FROM AUTHOR]

This paper introduces a new system that utilizes the advantages of boundary element analysis in structural engineering applications. A standardized building information model (BIM) for automated structural analysis and design of reinforced concrete plates based on the boundary element method (BEM) is proposed. Based on the model view definition approach, BIM standards are presented for the preprocessing and postprocessing of BEM analysis. Furthermore, standards are proposed for automated structural design of structural slab and beam elements based on the BEM analysis results. For each of the BIM components, standards are provided for the object structure, data flow, and graphical user interface (GUI). The extensibility of the software and applicability for a wide range of research and practical applications are considered in all the proposed standards. The system created can act as the basis for structural analysis and design of building floor and foundation problems. Object-oriented programming is used to implement the standards in a prototype. The prototype was verified by application to the solution of practical structural engineering problems. The performance of the proposed system is evaluated in terms of the modeling and the processing time required to analyze typical structural engineering applications using the prototype. [ABSTRACT FROM AUTHOR]

For this set of tests, the strain rate of the T-bar and centrifuge tests (calculated as the displacement normalized by the T-bar/pile diameter and divided by the time) were broadly comparable, as can be observed from Fig. Undrained shear strength against strain rate of simple shear, T-bar, and centrifuge tests. As noted in the original paper, the T-bar undrained shear strength gradient yielded a very similar value as the strength gradient calculated from the simple shear tests at a slow rate, despite the T-bars being performed at (considerably) higher strain rate than the slow simple shear tests. [Extracted from the article]

Some toe-deck crack cases in China have been reported after about 10 years of service in suspension and beam bridge steel orthotropic decks with trough stiffeners. In this paper, a reference stress method used in design practice and a hot-spot stress method provided by the International Institute of Welding are used to investigate toe-deck fatigue of the newly built Taizhou Yangtze River Bridge. Shell and solid finite element models with different mesh sizes are compared. The hot spot at the weld toe and the point at the trough-deck intersection are discussed. One is a shell-model hot spot with no weld. The other is a solid-model hot spot with the weld. Hot-spot stress calculated with the shell model is larger than that with the solid model. Different extrapolation methods of hot-spot stress are discussed; stress calculated with the linear extrapolation method is almost the same as with the quadratic method. The stress of the joint under a moving unit wheel load is studied. Fatigue strengths against reference and hot-spot stresses are derived. Fatigue damages under the truck load, evaluated based on the reference stress method and the hot-spot stress method, are compared. [ABSTRACT FROM AUTHOR]

Existing structures may be in need of seismic upgrading owing to structural deterioration, change in function or use, increased performance requirements, or modified seismic codes. In recent years, fluid viscous (FV) dampers have received increasing attention because of their notable seismic-reduction capacity and easy installation. This paper outlines the design procedure of seismic upgrading of existing buildings using FV dampers. Discussions are made on some key issues for seismic upgrading using FV dampers, including the analytical damper-brace model under large earthquakes and strategies for damper layout. A case study is made, in which a 21-story hotel built in 1991 was seismic upgraded. One special feature of this project is that only the first six stories can be structurally modified, resulting in limitations on the damper layout. According to the proposed design procedure, 56 FV dampers are suggested for this project, which provide a supplemental damping ratio of 5.3%. As a result, the seismic responses of upper stories could be significantly reduced, which avoids damaging the decoration of the building above its sixth story and enables short and economic construction. [ABSTRACT FROM AUTHOR]

The stiffness and strength of roof units and their connections to supporting beams are fundamental parameters to define the diaphragm behavior of precast structures. In this paper, an analytical method for the calculation of actions in floor-to-beam connections of roof systems without topping slab and without floor-to-floor connections is presented. The proposed procedure can be applied to rectangular single-story precast concrete frames of industrial buildings. One-span, multi-bays regular frames, characterized by symmetry of stiffness and mass distributions are analyzed by assuming floor-to-beam connections with infinite stiffness and strength. The procedure is applied in the perspective of capacity design approach by providing practical formulations for the design and retrofitting of floor-to-beam connections. This approach aims at concentrating the critical regions, where energy dissipation of the structure occurs, at the base of columns designed to fail in bending. An over-resisting behavior of the connections is achieved by over-proportioning them with respect to the resistance of the critical regions. To check the effectiveness of the presented approach, the results obtained with the analytical method are compared with the results of finite element analyses. [ABSTRACT FROM AUTHOR]

In order to investigate the safe operation, dynamic characteristics and stability of oil and gas submarine pipelines, the natural characteristics of a pipe span under elastic supporting conditions were studied. The pipe was simulated as a commonly supported beam considering the interaction of not only the fluid inside and outside the pipeline but the elastic coefficients of its supporting soil as well. The differential quadrature method (DQM), an efficient numerical method to solve boundary and initial value problems, was adopted to analyze the natural characteristics of a submarine span pipeline. The differential equation and its corresponding DQM simulation equations and boundary conditions were obtained. The impacts of several factors on natural frequency of free-span submarine pipelines were studied. These factors included soil elastic coefficients at pipeline ends, span length, outer diameter, flow velocity and pressure inside pipeline, flow velocity and fluid damping outside the pipeline, density of conveying fluid, and the axially sectional force. The analytical method and numerical results presented in the paper are of value for theoretical research and engineering applications. [ABSTRACT FROM AUTHOR]

Ronald Hamburger The writers thank the discusser for his interest in the paper as well as his comments. However, as discussed in Suzuki and Lignos ([23]; [21]), in large-magnitude earthquakes that exhibit long-duration characteristics [Fig. Beam-column element model calibrated for predicting flexural response leading to global collapse of RC frame buildings. [Extracted from the article]

The design of a water distribution network (WDN) is conceptually a multiobjective problem characterized by stringent constraints. Even in its most simple formulation, which requires only the maintenance of minimum pressures, it is difficult to solve, and the simplifications introduced often impair the practicality of the solutions. The paper aims at integrating an engineering approach to the optimization problem by generating pseudofronts in the hydraulically feasible region of the search space. The optimization algorithms provide an entirely feasible trade-off between cost and considered constraints, which may be directly used by a hypothetical decision maker. This engineering approach requires a fast tool to search for feasible solutions: the recently developed genetic heritage by stochastic evolution transmission (GHEST) algorithm, used herein, has proved to be effective and efficient in solving the optimal design problem of WDNs. Tests are carried out on two large-size water distribution networks (Balerma and Modena), using the GHEST algorithm, modified to account for several objectives. [ABSTRACT FROM AUTHOR]

The condition assessment of existing buildings with special reference to the analysis of degradation level has been extensively and fruitfully applied in the field of maintenance and monitoring. This paper presents a methodology for detecting structural degradation of the building that can be implemented in a decision support system consisting in a platform connected with smart devices. The proposed procedure is suitable for calculating the degradation of the building through a set of key performance indices and an optimized analytic hierarchy process. In addition, the methodology is calibrated through the well-known Tuutti model to consider the damage evolution of reinforcements' corrosion. The results show that this calibration increases the accuracy of the assessment but reduces the robustness of the method. Moreover, an optimal calibration point is identified by exploiting the results of a set of case studies performed in Italy, Portugal, and Brazil. Finally, the method is compared with a similar approach for the degradation analysis developed in the University of Brasilia. [ABSTRACT FROM AUTHOR]

To improve the swelling–shrinkage characteristics of expansive soil, excessive amounts of cement are often used to solidify it. This study aims to solidify expansive soil by using industrial graphene (G) and graphene oxide (GO)-modified cement to avoid the problem of environmental pollution resulting from the excessive use of cement. A series of unconsolidated-undrained triaxial and microstructure tests were conducted to investigate the engineering properties and micromechanisms of G and GO composite cement-solidified soils. Testing results showed that the deviatoric stress–strain curves of G and GO composite cement-solidified soils showed softening types. The compressive strength, toughness, shear strength, and ductility of cement-solidified soil were significantly improved by adding both G and GO. G and GO not only acted as a template to promote cement hydration and generate regular hydration products but also played a role in pore filling. Consequently, it is feasible to apply G and GO composite cement-solidified soils in practical projects. [ABSTRACT FROM AUTHOR]

The discusser thanks the authors for an extremely valuable contribution that will facilitate improved understanding of pile responses to cyclic lateral loading, as well as their improved modeling methods. The traditional HT ht methods date to the 1960s when the most common strength assessment tests used in calibrating them were undrained-unconsolidated triaxial tests, in situ vane, miniature vane, and unconfined compression tests. [Extracted from the article]

There has been a rapid development of high-speed rail in Spain. Many bridges have been constructed to carry these lines. The relevant Spanish design codes require static and dynamic testing of these structures for acceptance of the design and construction before opening for service; such testing is considered too costly in some other countries. This paper presents the concept, practice, and results of such testing for 119 precast and posttensioned concrete girder bridges. Their static and dynamic properties and responses to loads have implications for their structural safety, serviceability, and possibly durability. Inaccurate models used in design for static and dynamic parameters (such as stiffness, first natural frequency, and damping ratio) may result in incorrect responses and possibly unsafe structures; therefore, in situ testing is required. The test results of these structures also lead to an empirical relation between the first natural frequency and span length and a range of damping ratios for these types of structures, which can be useful for bridge engineers, particularly at a preliminary design stage of similar structures. [ABSTRACT FROM AUTHOR]

Institutional environment shapes the success of enterprise digital transformation, but its impact pathways, to our best knowledge, have received relatively little investigation, particularly in the fields of architecture, engineering, and construction (AEC). Grounded in neoinstitutional theory, this study conducted a fuzzy set qualitative comparative analysis of the effects of institutional pressure on digital transformation. The study yielded three results. First, the interaction of coercive, normative, and mimetic pressures can drive the digital transformation of AEC enterprises. For example, facing the digital delivery requirements of stakeholders and the pressure of digital collaboration in the supply chain, digital leaders in an enterprise will quickly apply internal pressure to raise the digitalization level. Also, in a highly competitive industry environment, the pressure to imitate the excellent digital transformation strategies of other enterprises comes with it. In a less competitive environment, however, digital leaders are the main pressure source to promote the digital transformation of enterprises. Second, we find that stakeholder vision, supply chain collaboration needs, and digital leaders are the key sources of digital transformation pressure. Third, high or low digitization levels cannot simply be explained by the opposite cause. Offering a new understanding of coercive, mimetic, and normative pressures on the complex digital transformation pathways of AEC enterprises, this study has implications for enterprises formulating digital transformation strategies. The findings point to the importance of corporate strategic change in the current digital environment, identify the institutional factors driving digital transformation, and will help AEC industry enterprises with different main businesses to respond to institutional pressures and improve the effectiveness of digital transformation through more targeted measures. This study can assist engineering enterprises around the world to develop digital transformation strategies. By exploring the complex causal relationships between the institutional environment and the digital transformation of engineering enterprises, this study provides a strong empirical foundation for new initiatives and policies to achieve high digitalization levels. [ABSTRACT FROM AUTHOR]

Natural geotextiles both woven and nonwoven have proved to be beneficial in stabilizing the weak subgrade by extending the service life of pavement and reducing the cost of construction. Nonwoven geotextiles can be used as separator in pavements as they allow in-plane permeability, but their tensile strength is low. In this study, an attempt is made to develop eco-friendly needle-punched coir latex composite sheets as an alternative to nonwoven coir geotextiles. Three types of products were developed by the impregnation of nonwoven needle-punched fabric with prevulcanized latex having densities 400, 600, and 800 grams per square meter (GSM). An experimental investigation on the effect of latex content on the mechanical properties of coir composites revealed that latex impregnation improves the mechanical properties of all coir composites and composites with 50% latex content exhibited maximum performance. Strength and drainage characteristics of reinforced soil-aggregate system were studied to evaluate the potential of coir composites as a separator in low volume roads by conducting the California bearing ratio (CBR) test, permeability, and transmissivity tests. The performance of the developed coir composites was compared with nonwoven coir felt and woven coir geotextile. It was found that 800 GSM coir composite showed 47% improvement in performance when compared to 400 GSM woven coir geotextile which showed only 40% performance improvement. [ABSTRACT FROM AUTHOR]

The most recent tendencies in pavement engineering design are directed to the return of the use of fundamental mechanical principles of engineering to predict design life through the concept of damage. Damage is associated with the relation between (1) the number of repetitions a material can resist until failure and (2) the predicted repetitions the designer is expecting during a period of time. Generally, mechanical responses as strains, stresses, and displacements are used to calculate the number of repetitions until a specific failure. In rigid pavements, there are analytical solutions that range from simple Westergaard's closed-form formulas to complex numerical solutions (as discrete-element methods and finite-element methods). This paper describes work done to develop an additional option in the middle: models calibrated to have the simplicity of the closed-form formulas and the accuracy of the finite-element methodology. Those models were then included in a graphical user interface, which will be used as the structural response engine in local mechanistic-empirical (M-E) design software. [ABSTRACT FROM AUTHOR]

Gravity currents play an important role in many aspects of natural processes and engineering practice. This paper presents a systematic lock-exchange experimental study to investigate the influence of linearly stratified environments and ramp slope on the hydrodynamics of gravity currents. A high-speed camcorder and particle image velocimetry (PIV) are applied to analyze the macro- and microstructures of gravity currents. It is observed that the front velocity of the gravity currents increases first then decreases for both stratified and unstratified environments. However, the density contrast that drives the currents decreases more quickly in stratified environments as the currents descend the ramp, causing more intense deceleration of the front velocity, which indicates the damping of ambient stratification on gravity currents. Based on the thermal theory, a new set of analytical formulas is then developed to determine the front location and velocity at the deceleration stage by considering the ambient density variation at depth. Further downstream, the currents would separate from the ramp and then horizontally intrude into the ambience where the currents are neutrally buoyant if the relative stratification parameter S > 1. An improved equation taking into account of the ramp slope, ambient stratification, and inflow buoyancy flux is proposed to predict the separation depth where the horizontal intrusion happens. Furthermore, velocity profiles in the body part of gravity currents are well predicted by two equations with three fitted parameters obtained by using the present experimental data. The vorticity fields of the gravity currents are quantitatively investigated to show that the weaker stratified ambience can lead to a stronger vorticity field, in which the Kelvin-Helmholtz instabilities and turbulent billows at the interface significantly affect the entrainment and mixing. In comparison with the gravity currents in the unstratified ambiance, the turbulent mixing in the stratified environments is generally reduced. The presence of stratification can result in a more complicated motion and fluid structure of the gravity currents. [ABSTRACT FROM AUTHOR]

Condition indexes have been developed to measure building component condition degradation due to age, use, and deterioration in support of asset management tasks related to work identification, planning, and prioritization. With the development of these indexes, a vast amount of condition index data have been collected for a wide range of components in buildings of varying type, use, and geographic location. The U.S. Department of Defense has implemented a standardized condition-assessment approach applied to thousands of Department-owned buildings, resulting in a vast condition index dataset to support more in-depth study of building component condition and reliability. This paper explores the existing data and develops a rigorous definition of the relationship between component condition, failure, and reliability. Presented is an approach using Markov transition probabilities to analyze the existing component condition datasets. This approach provides an improved method for predicting future condition index values based on past inspection results that are not based solely on inputs traditionally prone to error, such as component age and expected service life. It also results in a reliability metric that relates to a component's probability of failure, providing a much needed measure to manage risk. [ABSTRACT FROM AUTHOR]

Safe and economical design and assessment of reinforced (RC) and prestressed concrete (PC) beams requires the availability of accurate but simple formulations which adequately capture the structural response. In this paper, a mechanical model for the prediction of the shear-flexural strength of PC and RC members with rectangular, I, or T sections, with and without shear reinforcement, is presented. The model is based on the principles of concrete mechanics and on assumptions supported by the observed experimental behavior and by the results of refined numerical models. Compact, simple, and accurate expressions are derived for design and verification of the shear strength, which incorporate the most relevant shear transfer actions. Excellent agreement between the predictions of the model and the results of the recently published ACI-DAfStb databases, including more than 1,287 tests on RC and PC beams with and without stirrups, has been observed. The theory behind the model provides consistent explanations for many aspects related to the shear response that are not clearly explained by current code formulations, making it a very helpful tool for daily engineering practice. [ABSTRACT FROM AUTHOR]

In recent years, the concept of resilience has been introduced to the engineering field in particular related to disaster mitigation and management. However, the built environment is only part of the elements that support community functions. Maintaining community functionality during and after a disaster, defined as resilience, is influenced by multiple components. The paper is proposing a framework for measuring community resilience at different spatial and temporal scales. Seven dimensions are identified for measuring community resilience: population and demographics, environmental and ecosystem, organized governmental services, physical infrastructures, lifestyle and community competence, economic development, and social-cultural capital. They are summarized with the acronym PEOPLES. Each dimension is characterized by a corresponding performance metric that is combined with the other dimensions using a multilayered approach. Therefore, once a hybrid model of the community is defined, the proposed framework can be applied to measure its performance against any type of extreme event during emergency and in long term postdisaster phases. A resilience index can be determined to reflect all, or part, of the dimensions influencing the events. Several applications of part of such framework can already be found in literature for different types of infrastructures, physical and organizational (e.g., gas network, water distribution networks, health care facilities). The proposed framework can be used as decision support by stakeholders and managers and it can help planners in selecting the optimal restoration strategies that enhance the community resilience index. [ABSTRACT FROM AUTHOR]

Assessment of budget sufficiency and resource utilization for a resource-constrained project schedule is crucial to ensure practical feasibility of the schedule and successful delivery of a construction project. This paper proposes a quantitative assessment approach for characterizing budget sufficiency and resource utilization for a resource-constrained project schedule in an objective fashion. The budgeted unit, deployed unit, and scheduled unit in connection with a resource-constrained project schedule are first defined. Next, two budget sufficiency metrics, named the budget sufficiency index and budget sufficiency variance, are defined for measuring the sufficiency of control budget in terms of deploying resources to execute the project schedule with resource constraints. In addition, two resource utilization metrics, termed the resource utilization index and resource utilization variance, are defined for indicating utilization efficiency of deployed resources based on the schedule. The proposed metrics are applied to objectively assess multiple alternative resource-constrained project schedules derived from various approaches, including a practical scheduling approach (Primavera P6) and resource scheduling optimization techniques recently developed from in-house research. A textbook example and a refinery plant turnaround project are used to demonstrate the effective application of proposed metrics on alternative resource-constrained schedules. It is concluded that (1) resource scheduling optimization techniques outperform Primavera P6 in terms of budget sufficiency and resource utilization thanks to streamlining resource supply limits and shortening project duration by optimization; and (2) a significant portion of the idled resource time in the Primavera P6 schedule turns into extra contingency in the optimized schedule that can be reserved against any work unforeseen or unknown during the planning stage. [ABSTRACT FROM AUTHOR]

A representative curve number (CN) of a catchment is often calculated from the area-weighted average of CN values of unique land use and soil combinations. While convenient for implementation, this method is known to underestimate direct runoff depth. This paper investigates the mathematical mechanism of the expected underestimation and proposes alternative CN averaging methods called the quadratic and exact averaging methods, to handle the underestimation problem. Results suggest that the quadratic method could reduce the level of underestimation in direct runoff depth; further, the exact method could provide the same direct runoff depth as that of the areaweighted direct runoff depth averaging method. A representative CN is found to be a function of rainfall size and catchment landscape, and the underestimation is relatively large for small and mid-sized storm events. The improvement in runoff estimation with the newly proposed averaging methods is particularly beneficial to stormwater management, flood controls, and erosion controls upon small return-period events. [ABSTRACT FROM AUTHOR]

The September 28, 2018 earthquake and tsunami, which occurred north of Palu City, Indonesia, attracted widespread interest from the scientific community due to the unusually large tsunami that occurred after a strike-slip earthquake with a relatively small moment magnitude (MW = 7.5). To understand the structural performance of buildings and infrastructure under hydrodynamic loads and their associated effects, the authors conducted field surveys in Palu City. Light wooden frame constructions and masonry infill walls were common in the area, some of which were severely damaged by the earthquake and tsunami. Reinforced concrete structures remained predominantly intact, although they suffered soil-related issues such as scour around rigid building members. Local structural failures caused by the loss of supporting soil were also observed during the field survey, resulting in an overall reduction in the stability of the inspected structures. Based on the observations made, knowledge gaps and research needs concerning coastal and structural scouring are discussed. These are tied into the latest community research activities and put in the context of a published ASCE standard chapter that discusses tsunami design. [ABSTRACT FROM AUTHOR]