http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2013 , Hindawi Publishing Corporation . All rights reserved. Thu, 09 May 2013 13:49:49 +0000 http://www.hindawi.com/journals/ace/2013/426932/ The model tuning through sensitivity analysis is a prominent procedure to assess the structural behavior and dynamic characteristics of cable-stayed bridges. Most of the previous sensitivity-based model tuning methods are automatic iterative processes; however, the results of recent studies show that the most reasonable results are achievable by applying the manual methods to update the analytical model of cable-stayed bridges. This paper presents a model updating algorithm for highly redundant cable-stayed bridges that can be used as an iterative manual procedure. The updating parameters are selected through the sensitivity analysis which helps to better understand the structural behavior of the bridge. The finite element model of Tatara Bridge is considered for the numerical studies. The results of the simulations indicate the efficiency and applicability of the presented manual tuning method for updating the finite element model of cable-stayed bridges. The new aspects regarding effective material and structural parameters and model tuning procedure presented in this paper will be useful for analyzing and model updating of cable-stayed bridges. B. Asgari, S. A. Osman, and A. Adnan Copyright © 2013 B. Asgari et al. All rights reserved. Thu, 02 May 2013 10:55:12 +0000 http://www.hindawi.com/journals/ace/2013/189105/ Considering facilities management (FM) at the early design stage could potentially reduce the efforts for maintenance during the operational phase of facilities. Few efforts in construction industry have involved facility managers into the design phase. It was suggested that early adoption of facilities management will contribute to reducing the needs for major repairs and alternations that will otherwise occur at the operational phase. There should be an integrated data source providing information support for the building lifecycle. It is envisaged that Building Information Modelling (BIM) would fill the gap by acting as a visual model and a database throughout the building lifecycle. This paper develops a framework of how FM can be considered in design stage through BIM. Based on the framework, the paper explores how BIM will beneficially support FM in the design phase, such as space planning and energy analysis. A case study of using BIM to design facility managers’ travelling path in the maintenance process is presented. The results show that early adoption of FM in design stage with BIM can significantly reduce life cycle costs. Ying Wang, Xiangyu Wang, Jun Wang, Ping Yung, and Guo Jun Copyright © 2013 Ying Wang et al. All rights reserved. Wed, 10 Apr 2013 14:54:25 +0000 http://www.hindawi.com/journals/ace/2013/868791/ This paper particularly addresses the market implementation of Fibre Reinforced Polymer (FRP) for bridges. It presents the concept of demand and supply chain innovation as being investigated within two ongoing European collaborative research projects (FP7) titled Trans-IND and PANTURA. FRP has emerged as a real alternative structural material based on various sustainability considerations, among others the reduced life-cycle cost due to less maintenance needs, longer lifetime, and easiness to repair, replace, or recycle the components. The Trans-IND research project aims to develop and demonstrate new industrialized processes to use FRP for civil infrastructure projects at a large scale. In order to be cost effective, a new value-chain strategy for the design, realization, and maintenance of FRP bridges is required to replace the fragmented supply chain and the one-off approach to a construction project. This paper focuses on the development of new business models based on asset management strategy, which covers the entire demand and supply chains. Research on new business models is supported by the insight into the market and regulatory frameworks in different EU countries. This is based on field surveys across the EU that have been carried out as a part of the Trans-IND and PANTURA collaborative research projects. Rizal Sebastian Copyright © 2013 Rizal Sebastian. All rights reserved. Tue, 08 Jan 2013 16:25:52 +0000 http://www.hindawi.com/journals/ace/2013/602364/ During the last years, in many developed countries, administrations and private companies have devoted considerable amounts of money to obtain mapping data using airborne LiDAR. For many civil activities, we can take advantage of it, since those data are available with no cost. Some important questions arise: Are those data good enough to be used for determining the heights of the civil constructions with the accuracy we need in some civil work? What accuracy can we expect when using low-density LiDAR data (0.5 pts/m2)? In order to answer those questions, we have developed a specific methodology based on establishing a set of control points on the top of several constructions and calculating the elevation of each one using postprocessing GPS. Those results have been taken as correct values and the comparison between those values and the elevations obtained, assigning values to the control points by the interpolation of the LiDAR dataset, has been carried out. This paper shows the results obtained using low-density airborne LiDAR data and the accuracy obtained. Results have shown that LiDAR can be accurate enough (10–25 cm) to determine the height of civil constructions and apply those data in many civil engineering activities. Rubén Martínez Marín, Elena Lianes Revilla, Juan Carlos Ojeda Manrique, and Miguel Marchamalo Sacristán Copyright © 2012 Rubén Martínez Marín et al. All rights reserved. Tue, 25 Dec 2012 14:16:27 +0000 http://www.hindawi.com/journals/ace/2012/912612/ Sami W. Tabsh and Husam Najm Copyright © 2012 Sami W. Tabsh and Husam Najm. All rights reserved. Wed, 19 Dec 2012 09:19:11 +0000 http://www.hindawi.com/journals/ace/2012/626592/ This paper describes the design of a novel semi-prefabricated LVL-concrete composite floor that has been developed in New Zealand. In this solution, the floor units made from LVL joists and plywood are prefabricated in the factory and transported to the building site. The units are then lifted onto the supports and connected to the main frames of the building and to the adjacent units. Finally, a concrete topping is poured on top of the units in order to form a continuous slab connecting all the units. Rectangular notches cut from the LVL joists and reinforced with coach screws provide the composite action between the concrete slab and the LVL joists. This system proved to be an effective modular solution that ensures rapid construction. A design procedure based on the use of the effective flexural stiffness method, also known as the “gamma method” is proposed for the design of the composite floor at ultimate and serviceability limit states, in the short and long term. By comparison with the experimental results, it is shown that the proposed method leads to conservative design. A step-by-step design worked example of this novel semi-prefabricated composite floor concludes the paper. David Yeoh and Massimo Fragiacomo Copyright © 2012 David Yeoh and Massimo Fragiacomo. All rights reserved. Thu, 13 Dec 2012 13:32:47 +0000 http://www.hindawi.com/journals/ace/2012/153123/ Electrokinetic treatment has been known in geotechnical engineering for over six decades, yet, the technique is rarely used. This stems from the absence of design guidelines and specifications for electrokinetic treatment systems. An important issue that need to be investigated and understood in order to devise guidelines from experimental results is the effect of the foundation element size on the outcome of the treatment. Also important is determining the optimum distance between the electrodes and estimating the energy consumption prior to treatment. This experimental study is a preliminary step in understanding some of the issues critical for the guidelines and specifications. Four model caissons with surface areas between 16000 and 128000 mm2 were embedded in soft clayey soil under water and treated for 168 hr with a dc voltage of 6 V. From the results, a distance between the anode (model caisson) and the cathode equal 0.25 times the outside diameter of the model caisson was identified as optimum. Relationships between the surface area and axial capacity of the model caisson and the surface area and energy consumption were presented. The equations can be used to preliminary estimate the load capacity and the energy consumption for full-scale applications. Eltayeb Mohamedelhassan, Kevin Curtain, Matt Fenos, Kevin Girard, Anthony Provenzano, and Wesley Tabaczuk Copyright © 2012 Eltayeb Mohamedelhassan et al. All rights reserved. Sun, 02 Dec 2012 16:08:13 +0000 http://www.hindawi.com/journals/ace/2012/749540/ On the basis of evidence from model tests on increasing the end-bearing behavior of tapered piles at the load-settlement curve, this paper proposes an analytical spherical cavity expansion theory to evaluate the end-bearing capacity. The angle of tapering is inserted in the proposed model to evaluate the end-bearing capacity. The test results of the proposed model in different types of sands and different relative densities show good effects compared to conventional straight piles. The end-bearing capacity increases with increases in the tapering angle. The paper then propounds a model for prototypes and real-type pile tests which predicts and validates to evaluate the end-bearing capacity. Suman Manandhar and Noriyuki Yasufuku Copyright © 2012 Suman Manandhar and Noriyuki Yasufuku. All rights reserved. Thu, 29 Nov 2012 16:27:52 +0000 http://www.hindawi.com/journals/ace/2012/780379/ This paper describes two prototype applications based on the Virtual Reality (VR) technology for use in maintenance planning of buildings. In a building, the paint coating applied to interior walls and the different types of materials applied to façades convey their aesthetic character and also perform an important function of protection. This a construction component which is exposed to agents of deterioration related to its use, needing the regular evaluation of its state of repair. The applications support the performance of such periodic inspections and the monitoring of interior and exterior wall maintenance, using the VR technology. Used during an inspection visit, the applications allow users to consult a database of irregularities, normally associated with the coating, classified by the most probable causes and by the recommended repair methodologies. In addition, a chromatic scale related to the degree of deterioration of the coating, defined as a function of the time between the dates of the application of the paint and the scheduled repainting, can be attributed to each element of coating monitored. This use of the VR technology allows inspections and the evaluation of the degree of wear and tear of materials to be carried out in a highly direct and intuitive manner. A. Z. Sampaio, D. P. Rosário, and A. R. Gomes Copyright © 2012 A. Z. Sampaio et al. All rights reserved. Sun, 18 Nov 2012 08:24:29 +0000 http://www.hindawi.com/journals/ace/2012/907431/ The addition of steel fibers into concrete mix can significantly improve the engineering properties of concrete. The mechanical behaviors of steel fiber reinforced high-performance concrete with fly ash (SFRHPFAC) are studied in this paper through both static compression test and dynamic impact test. Cylindrical and cube specimens with three volume fractions of end-hooked steel fibers with volume fraction of 0.5%, 1.0%, and 1.5% (39.25, 78.50, and 117.75 kg/m3) and aspect ratio of 64 are used. These specimens are then tested for static compression and for dynamic impact by split Hopkinson pressure bar (SHPB) at strain rate of 30–60 s−1. The results reveal that the failure mode of concrete considerably changes from brittle to ductile with the addition of steel fibers. The plain concrete may fail under low-strain-rate single impact whereas the fibrous concrete can resist impact at high strain rate loading. It is shown that strain rate has great influence on concrete strength. Besides, toughness energy is proportional to the fiber content in both static and dynamic compressions. Tan Chien Yet, R. Hamid, and Mudiono Kasmuri Copyright © 2012 Tan Chien Yet et al. All rights reserved. Mon, 15 Oct 2012 11:06:55 +0000 http://www.hindawi.com/journals/ace/2012/145850/ In the state of New Mexico (USA), passenger rail began in 2008 between Belen and Santa Fe on the Rail Runner, following the acquisition of about 100 miles of existing rail and related infrastructure. Many of the bridges on this route are over 100 years old and contain fatigue prone details. This study focuses on a steel through-girder bridge along this corridor. To accurately evaluate these structures for load carrying capacity and fatigue, an accurate analytical model is required. Accordingly, four models were developed to study the sensitivity of a bridge in New Mexico to floor-system connection fixity and the ballast. A diagnostic load test was also performed to evaluate the accuracy of the finite-element models at locations of maximum moments. Comparisons between the simulated and measured bridge response were made based on strain profiles, peak strains, and Palmgren-Miner’s sums. It was found that the models including the ballast were most accurate. In most cases, the pinned ended models were closer to the measured strains. The floor beams and girders were relatively insensitive to the ballast and end conditions of the floor-system members, whereas the stringers were sensitive to the modeling of the ballast. Andrew N. Daumueller and David V. Jáuregui Copyright © 2012 Andrew N. Daumueller and David V. Jáuregui. All rights reserved. Mon, 30 Jul 2012 13:14:16 +0000 http://www.hindawi.com/journals/ace/2012/643543/ The major problems affecting the service life of bridges are related to various factors such as fatigue-sensitive details, increased service loads, corrosion deterioration, and the lack of proper maintenance. Among them, corrosion deterioration and fatigue damages of structures particularly to steel girder bridges are the most common ones. Bridges of different structural forms, at different locations or under different climates, may suffer from various degrees of deterioration. Steel girders at different positions of a bridge may also suffer from different degrees of damage. How to effectively maintain the bridge asset at a minimal cost and how to predict the time for future works are crucial, particularly when government funding sources become stretched. A comprehensive bridge management framework assisting stakeholders to appropriately and reasonably prioritize their future maintenance-related works in their bridge stocks, such that stakeholders can better allocate the limited resources, is utmost concerned. This paper proposes an integrated life-cycle management (LCM) strategy on steel girders in bridges in which corrosion deterioration and fatigue damage prediction models are mapped with girders’ performance conditions. A practical example to demonstrate the applicability of the proposed LCM strategy is also illustrated. Kevin K. L. So, Moe M. S. Cheung, and Eric X. Q. Zhang Copyright © 2012 Kevin K. L. So et al. All rights reserved. Sun, 08 Jul 2012 11:14:24 +0000 http://www.hindawi.com/journals/ace/2012/673821/ With the Federal Highway Administration-mandated implementation of the LRFD specifications, many state departments of transportation (DOTs) have already started implementing LRFD specifications as developed by the AASHTO. Many aspects of the LRFD specifications are being investigated by DOTs and researchers in order for seamless implementation for design and analysis purposes. This paper presents the investigation on several design aspects of post-tensioned box girder bridges designed by LRFD Specifications using conventional or High-Strength Concrete (HSC). A computer spreadsheet application was specifically developed for this investigation. It is capable of analysis, design, and cost evaluation of the superstructure for a cast-in-place post-tensioned box girder bridge. Optimal design of a post-tensioned box girder is achievable by correct selection of design variables. Cost evaluation of superstructures with different geometrical and material configurations has led to the development of optimum design charts for these types of superstructures. Variables used to develop these charts include, among others, span length, section depth, web spacing, tendon profile, and concrete strength. It was observed that HSC enables the achievement of significantly longer span lengths and/or longer web spacing that is not achievable when using normal strength concrete. Byungik Chang, Kamal Mirtalaei, Seungyeol Lee, and Kenneth Leitch Copyright © 2012 Byungik Chang et al. All rights reserved. Thu, 05 Jul 2012 13:52:36 +0000 http://www.hindawi.com/journals/ace/2012/935329/ The U.S. Departments of Transportation adopted the AASHTO LRFD Bridge Design Specifications during the year 2007, which is mandated by AASHTO and FHWA. The application of LRFD specification initiated numerous research works in this field. This investigation addresses the LRFD and Standard design methodologies of concrete deck slab, deck overhang, barrier and combined barrier-bridge overhang. The purpose of this study is to propose a simplified manual design approach for the barrier-deck overhang in concrete bridges. For concrete deck slab overhang and barrier, application of National Cooperative Highway Research Program crash test is reviewed. The failure mechanism, design philosophy and load cases including extreme event limit states for barrier and overhang are discussed. The overhang design for the combined effect of bending moment and axial tension is probably the most important part of the design process. The overhang might be a critical design point of the deck with significantly higher amount of reinforcement. The design process becomes complicated due to combined force effect, LRFD crash test level requirement and the existence of several load combinations. Using this program, different LRFD load combinations are plotted together with the interaction diagram and the design is validated. Byungik Chang, Kamal Mirtalaei, Seungyeol Lee, and Kenneth Leitch Copyright © 2012 Byungik Chang et al. All rights reserved. Sun, 27 May 2012 13:50:37 +0000 http://www.hindawi.com/journals/ace/2012/524396/ Piervincenzo Rizzo, Lingyu (Lucy) Yu, and Alessandro Marzani Copyright © 2012 Piervincenzo Rizzo et al. All rights reserved. Wed, 23 May 2012 14:23:00 +0000 http://www.hindawi.com/journals/ace/2012/452987/ The paper investigated the use of fiberglass-reinforced plastic (FRP) grid for reinforcement in link slabs for jointless bridge decks. The design concept of link slab was examined based on the ductility of the fiberglass-reinforced plastic grid to accommodate bridge deck deformations. The implementation of hybrid simulation assisted in combining the experimental results and the theoretical work. The numerical analyses and the experimental work investigated the behavior of the link slab and confirmed its feasibility. The results indicated that the technique would allow simultaneous achievement of structural need, lower flexural stiffness of the link slab approaching the behavior of a hinge, and sustainability need of the link slab. The outcome of the study supports the contention that jointless concrete bridge decks may be designed and constructed with fiberglass-reinforced plastic grid link slabs. This concept would also provide a solution to a number of deterioration problems associated with bridge deck joints and can be used during new construction of bridge decks. The federal highway administration provided funds to Louisiana Department of Transportation through the innovative bridge research and development program to implement the use of FRP grid as link slab. Aziz Saber and Ashok Reddy Aleti Copyright © 2012 Aziz Saber and Ashok Reddy Aleti. All rights reserved. Wed, 23 May 2012 10:56:44 +0000 http://www.hindawi.com/journals/ace/2012/813281/ Guided wave technique is an efficient method for monitoring structural integrity by detecting and forecasting possible damages in distributed pipe networks. Efficient detection depends on appropriate selection of guided wave modes as well as signal processing techniques. Fourier analysis and wavelet analysis are two popular signal processing techniques that provide a flexible set of tools for solving various fundamental problems in science and engineering. In this paper, effective ways of using Fourier and Wavelet analyses on guided wave signals for detecting defects in steel pipes are discussed for different boundary conditions. This research investigates the effectiveness of Fourier transforms and Wavelet analysis in detecting defects in steel pipes. Cylindrical Guided waves are generated by piezo-electric transducers and propagated through the pipe wall boundaries in a pitch-catch system. Fourier transforms of received signals give information regarding the propagating guided wave modes which helps in detecting defects by selecting appropriate modes that are affected by the presence of defects. Continuous wavelet coefficients are found to be sensitive to defects. Several types of mother wavelet functions such as Daubechies, Symlet, and Meyer have been used for the continuous wavelet transform to investigate the most suitable wavelet function for defect detection. This research also investigates the effect of different boundary conditions on wavelet transforms for different mother wavelet functions. Rais Ahmad and Tribikram Kundu Copyright © 2012 Rais Ahmad and Tribikram Kundu. All rights reserved. Tue, 22 May 2012 15:09:12 +0000 http://www.hindawi.com/journals/ace/2012/267584/ This study carries out a parametrical analysis of the seismic response to asynchronous earthquake ground motion of a long multispan rc bridge, the Fener bridge, located on a high seismicity area in the north-east of Italy. A parametrical analysis has been performed investigating the influence of the seismic input correlation level on the structural response: a series of nonlinear time history analyses have been executed, in which the variation of the frequency content in the accelerograms at the pier bases has been described by considering the power spectral density function (PSD) and the coherency function (CF). In order to include the effects due to the main nonlinear behaviours of the bridge components, a 3D finite element model has been developed, in which the pounding of decks at cap-beams, the friction of beams at bearings, and the hysteretic behaviour of piers have been accounted for. The sensitivity analysis has shown that the asynchronism of ground motion greatly influences pounding forces and deck-pier differential displacements, and these effects have to be accurately taken into account for the design and the vulnerability assessment of long multispan simply supported bridges. G. Tecchio, M. Grendene, and C. Modena Copyright © 2012 G. Tecchio et al. All rights reserved. Tue, 22 May 2012 15:07:16 +0000 http://www.hindawi.com/journals/ace/2012/463134/ A short computer program, fully documented, is presented, for the step-by-step dynamic analysis of isolated cables or couples of parallel cables of a cable-stayed bridge, connected to each other and possibly with the deck of the bridge, by very thin pretensioned wires (cross-ties) and subjected to variation of their axial forces due to traffic or to successive pulses of a wind drag force. A simplified SDOF model, approximating the fundamental vibration mode, is adopted for every individual cable. The geometric nonlinearity of the cables is taken into account by their geometric stiffness, whereas the material nonlinearities of the cross-ties include compressive loosening, tensile yielding, and hysteresis stress-strain loops. Seven numerical experiments are performed. Based on them, it is observed that if two interconnected parallel cables have different dynamic characteristics, for example different lengths, thus different masses, weights, and geometric stiffnesses, too, or if one of them has a small additional mass, then a single pretensioned very thin wire, connecting them to each other and possibly with the deck of the bridge, proves effective in suppressing, by its hysteresis damping, the vibrations of the cables. Panagis G. Papadopoulos, Andreas Diamantopoulos, Haris Xenidis, and Panos Lazaridis Copyright © 2012 Panagis G. Papadopoulos et al. All rights reserved. Mon, 21 May 2012 08:33:11 +0000 http://www.hindawi.com/journals/ace/2012/450981/ Experimental data are presented for six concrete specimens subjected to displacement reversals. Two specimens were reinforced longitudinally with steel bars Grade 410 (60 ksi), two with Grade 670 (97 ksi), and two with Grade 830 (120 ksi). Other experimental variables included axial load (0 or 0.2 𝑓𝑐𝐴g) and volume fraction of hooked steel fibers (0 or 1.5%). All transverse reinforcement was Grade 410, and the nominal concrete compressive strength was 41 MPa (6 ksi). The loading protocol consisted of repeated cycles of increasing lateral displacement reversals (up to 5% drift) followed by a monotonic lateral push to failure. The test data indicate that replacing conventional Grade-410 longitudinal reinforcement with reduced amounts of Grade-670 or Grade-830 steel bars did not cause a decrease in usable deformation capacity nor a decrease in flexural strength. The evidence presented shows that the use of advanced high-strength steel as longitudinal reinforcement in frame members is a viable option for earthquake-resistant construction. Andres Lepage, Hooman Tavallali, Santiago Pujol, and Jeffrey M. Rautenberg Copyright © 2012 Andres Lepage et al. All rights reserved. Wed, 16 May 2012 10:15:29 +0000 http://www.hindawi.com/journals/ace/2012/579732/ The aim of this study is to investigate the strengths and drying shrinkage of alkali-activated slag paste and mortar. Compressive strength, tensile strength, and drying shrinkage of alkali-activated slag paste and mortar were measured with various liquid/slag ratios, sand/slag ratios, curing ages, and curing temperatures. Experimental results show that the higher compressive strength and tensile strength have been observed in the higher curing temperature. At the age of 56 days, AAS mortars show higher compressive strength than Portland cement mortars and AAS mortars with liquid/slag ratio of 0.54 have the highest tensile strength in all AAS mortars. In addition, AAS pastes of the drying shrinkage are higher than AAS mortars. Meanwhile, higher drying shrinkage was observed in AAS mortars than that observed comparable Portland cement mortars. Mao-chieh Chi, Jiang-jhy Chang, and Ran Huang Copyright © 2012 Mao-chieh Chi et al. All rights reserved. Wed, 16 May 2012 08:01:23 +0000 http://www.hindawi.com/journals/ace/2012/595238/ This paper presents analyses of the seismic responses of two reinforced concrete buildings monitored for a period of more than two years. One of the structures was a three-storey reinforced concrete (RC) frame building with a shear core, while the other was a three-storey RC frame building without a core. Both buildings are part of the same large complex but are seismically separated from the rest of it. Statistical analysis of the relationships between maximum free field accelerations and responses at different points on the buildings was conducted and demonstrated strong correlation between those. System identification studies using recorded accelerations were undertaken and revealed that natural frequencies and damping ratios of the building structures vary during different earthquake excitations. This variation was statistically examined and relationships between identified natural frequencies and damping ratios, and the peak response acceleration at the roof level were developed. A general trend of decreasing modal frequencies and increasing damping ratios was observed with increased level of shaking and response. Moreover, the influence of soil structure interaction (SSI) on the modal characteristics was evaluated. SSI effects decreased the modal frequencies and increased some of the damping ratios. Faheem Butt and Piotr Omenzetter Copyright © 2012 Faheem Butt and Piotr Omenzetter. All rights reserved. Tue, 15 May 2012 11:08:09 +0000 http://www.hindawi.com/journals/ace/2012/357346/ This paper presents the results of an experimental and computational investigation tailored to examine the response of glass fiber-reinforced-plastic-(GFRP-) reinforced glue-laminated curved beams and arches. The main objective was to ascertain the viability of GFRP as an effective reinforcement for enhancing the load carrying capacity and stiffness of such curved structures. The study included optimization of the length and thickness of the GFRP reinforcement. In doing so, first a parametric finite element study was conducted to evaluate the influence of unidirectional GFRP reinforcement applied onto the arch using eleven possible configurations and different thicknesses. Subsequently, an experimental investigation was conducted to verify the results established by the finite element method as well as the integrity of actual GFRP-reinforced glue-laminated curved structures. The results indicate that GFRP can be considered as an effective and economically viable solution for strengthening and stiffening glulam arches, without adding any appreciable weight to the structure. S. Alshurafa, H. Alhayek, and F. Taheri Copyright © 2012 S. Alshurafa et al. All rights reserved. Mon, 07 May 2012 15:03:35 +0000 http://www.hindawi.com/journals/ace/2012/380795/ The work described in this paper provides an evaluation of an aged pervious concrete pavement in the Northeastern United States to provide a better understanding of the long-lasting effects of placement techniques as well as the long-term field performance of porous pavement, specifically in areas susceptible to freezing and thawing. Multiple samples were taken from the existing pavement and were examined in terms of porosity and unit weight, compressive and splitting tensile strength, and the depth and degree of clogging. It was concluded that improper placement and curing led to uneven pavement thickness, irregular pore distribution within the pervious concrete, and highly variable strength values across the site, as well as sealed surfaces that prevented infiltration. Aleksandra Radlinska, Andrea Welker, Kathryn Greising, Blake Campbell, and David Littlewood Copyright © 2012 Aleksandra Radlińska et al. All rights reserved. Mon, 07 May 2012 14:58:14 +0000 http://www.hindawi.com/journals/ace/2012/625395/ The thermal conductivity measurement by a simplified transient hot-wire technique is applied to geomaterials in order to show the relationships which can exist between effective thermal conductivity, texture, and moisture of the materials. After a validation of the used “one hot-wire” technique in water, toluene, and glass-bead assemblages, the investigations were performed (1) in glass-bead assemblages of different diameters in dried, water, and acetone-saturated states in order to observe the role of grain sizes and saturation on the effective thermal conductivity, (2) in a compacted earth brick at different moisture states, and (3) in a lime-hemp concrete during 110 days following its manufacture. The lime-hemp concrete allows the measurements during the setting, desiccation and carbonation steps. The recorded Δ𝑇/ln(𝑡) diagrams allow the calculation of one effective thermal conductivity in the continuous and homogeneous fluids and two effective thermal conductivities in the heterogeneous solids. The first one measured in the short time acquisitions (<1 s) mainly depends on the contact between the wire and grains and thus microtexture and hydrated state of the material. The second one, measured for longer time acquisitions, characterizes the mean effective thermal conductivity of the material. B. Merckx, P. Dudoignon, J. P. Garnier, and D. Marchand Copyright © 2012 B. Merckx et al. All rights reserved. Sun, 29 Apr 2012 14:40:36 +0000 http://www.hindawi.com/journals/ace/2012/910203/ Conjunctive management of water resources involves coordinating use of surface water and groundwater resources. Very few simulation/optimization (S-O) models for stream-aquifer system management have included detailed interactions between groundwater, streams, and reservoir storage. This paper presents an S-O model doing that via artificial neural network simulators and genetic algorithm optimizer for multiobjective conjunctive water use problems. The model simultaneously addresses all significant flows including reservoir-stream-diversion-aquifer interactions in a more detailed manner than previous models. The model simultaneously maximizes total water provided and hydropower production. A penalty function implicitly poses constraints on state variables. The model effectively finds feasible optimal solutions and the Pareto optimum. Illustrated is application for planning water resource and minihydropower system development. Hala Fayad, Richard C. Peralta, and Ali Forghani Copyright © 2012 Hala Fayad et al. All rights reserved. Thu, 26 Apr 2012 14:47:32 +0000 http://www.hindawi.com/journals/ace/2012/635176/ The effectiveness of externally bonded sprayed glass fiber reinforced polymer (Sprayed GFRP) in shear strengthening of RC beams under quasi-static loading is investigated. Different techniques were utilized to enhance the bond between concrete and Sprayed GFRP, involving the use of through bolts and nuts paired with concrete surface preparation through sandblasting and through the use of a pneumatic chisel prior to Sprayed GFRP application. It was found that roughening the concrete surface using a pneumatic chisel and using through bolts and nuts were the most effective techniques. Also, Sprayed GFRP applied on 3 sides (U-shaped) was found to be more effective than 2-sided Sprayed GFRP in shear strengthening. Sprayed GFRP increased the shear load-carrying capacity and energy absorption capacities of RC beams. It was found that the load-carrying capacity of strengthened RC beams was related to an effective strain of applied Sprayed GFRP. This strain was related to Sprayed GFRP configuration and the technique used to enhance the concrete-FRP bond. Finally, an equation was proposed to calculate the contribution of Sprayed GFRP in the shear strength of an RC beam. Sayed Mohamad Soleimani and Nemkumar Banthia Copyright © 2012 Sayed Mohamad Soleimani and Nemkumar Banthia. All rights reserved. Thu, 19 Apr 2012 10:46:27 +0000 http://www.hindawi.com/journals/ace/2012/381834/ The seismic response of linearly elastic, idealized single-storey, one-way asymmetric building with semiactive magnetorheological (MR) dampers with clipped-optimal algorithm is investigated. The response is obtained by numerically solving the governing equations of motion. The effects of eccentricity ratio, uncoupled time period, and ratio of uncoupled torsional to lateral frequency are investigated on peak responses which include lateral, torsional and edge displacements and their acceleration counter parts, base shear, and control forces. To study the effectiveness of control system, the controlled response of asymmetric system is compared with the corresponding uncontrolled response. Further, controlled response of asymmetric system is compared with corresponding symmetric system to study the effects of torsional coupling. It is shown that the implementation of semiactive dampers reduces the deformations significantly. Also, the effects of torsional coupling on effectiveness of semiactive system are found to be more sensitive to the variation of eccentricity and torsional to lateral frequency ratio. Snehal V. Mevada and R. S. Jangid Copyright © 2012 Snehal V. Mevada and R. S. Jangid. All rights reserved. Tue, 17 Apr 2012 10:55:43 +0000 http://www.hindawi.com/journals/ace/2012/693506/ New experimental data on plan dimensions for riprap mattresses used in pile group protection against edge failure are analyzed. The influence of flow conditions and the distance between piles in plan dimensions of riprap mattresses are addressed. An alternative methodology for the experimental study of edge failure in pile groups is proposed and verified, significantly reducing the duration of tests (from several days to a few hours) and yielding similar results. For the pile group configuration tested, a design expression for minimum riprap width is obtained. The influence of the distance between the piles on the width of riprap dimensions is shown to be small, and the proposed expression compares well with some of the expressions for single piers found in the literature. Christian Chreties, Luis Teixeira, and Gonzalo Simarro Copyright © 2012 Christian Chreties et al. All rights reserved. Wed, 11 Apr 2012 15:52:02 +0000 http://www.hindawi.com/journals/ace/2012/523839/ The 3D numerical simulation was carried out for an idealized Rankine vortex using nonlinear k-ε model (one kind of RANS model) and large eddy simulation (LES) techniques. In this 3D simulation, the vortex flow field was given to rotate with the vertical axis in a free surface rectangular domain. In order to investigate the predictability of standard (linear) and non-linear k-ε models, the decay of a trailing vortex was simulated and compared with previous DNS data. The governing equations for mean velocities and turbulent flows were discretized with the finite volume method based on a staggered grid system. It was observed that in the growth phase as well as in stabilized phase of turbulence, the decay rate of tangential velocity by RANS model was well comparable with LES simulation as well as previous DNS data. However, in the decay phase of turbulence, RANS model showed slightly faster decay of tangential velocity due to its slower decay of turbulence compared to LES or DNS. The patterns as well as magnitudes of secondary currents predicted by RANS and LES models were well comparable to each other. Md. Shahjahan Ali, Takashi Hosoda, and Ichiro Kimura Copyright © 2012 Md. Shahjahan Ali et al. All rights reserved.