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This paper introduces the study on treatment on the secondary biochemical effluent of pulp and paper wastewater by ozonation, and investigates the effects of the ozonation process on the wastewater COD, chroma, UV 254 and turbidity removal efficiency during ozone dosage, contact time and so on. The results showed that ozonation treatment effect was good, and with the increase of ozone dosage and contact time, the wastewater COD, chroma and UV 254 experimental conditions removal rate was increasing, and the optimum were that the ozone dosage was 126.46~147.37mg/L and contact time was 1.30~1.74h. Ozonation has a certain removal efficiency for turbidity, and turbidity removal rate was in a large range of 1.88~77.51%, but there is no obvious correlation with the ozone dosage and contact time.

Over the last few years, students taking the Introduction to Geotechnical Engineering course at Tufts University have performed term projects where they develop written reports and oral presentations on various topics in geo-engineering. This paper presents how these efforts have enhanced the learning experience of the course. Specifically, the paper presents how the project is integrated into the course, assessment methods used for grading, and the value such projects have had on student learning, based on post-course evaluations. A shortened example of a student’s work is presented. It can be concluded that the project allows not only a deeper appreciation of geo-engineering by the students, but also provides an avenue for students to practice their communication skills; one of the ABET Criterion 3 outcomes.

A complex cleanup project that included dredging and capping of contaminated sediment, construction of two breakwaters, habitat enhancement, upgrade of a seasonal small craft facility and installation of new aids to navigation was completed by the Port of Anacortes, Washington in collaboration with the Department of Ecology, Washington and potentially responsible parties (PRP). The complexity of project site physical processes, extent of dredging, and strict regulatory requirements on the clean-up action necessitated an innovative engineering approach to all above elements of the project. The approach also included application of the most advanced coastal engineering modeling tools including wave, tidal flow, sediment transport and stability, and coastal geomorphology hydrodynamic simulators. Based on analysis of the numerical modeling results, optimal engineering decisions were made for design and construction of detached breakwaters, dredging and removing a portion of the contaminated sediment, capping of the remaining contaminated sediment, and removing the old deteriorating creosoted sheetpile wall breakwater. Also, the results of the study determined the possibility of creating a sheltered eelgrass habitat and year-round small craft facility for different types of activities such as fishing, kayaking, and sailing.

The FEMA P695 Methodology, developed through the recent ATC-63 Project, incorporates ground motion guidelines that include a so-called Spectral Shape Factor (SSF). This SSF adjusts the predicted collapse capacity of the building to account for the spectral shape of ground motions. This paper explains how aspects of this new FEMA P695 Methodology could be adapted for use in refining the target displacement equation (i.e. inelastic displacement demand) in the ASCE/SEI 41 Nonlinear Static Method to account for spectral shape. The final result would be an additional coefficient (termed the “spectral shape coefficient”) that would reduce the target displacement for sites where the ground motion is expected to have a less damaging spectral shape. This paper outlines how one would compute this spectral shape coefficient for any site and building of interest, and then explains the additional work needed to implement this new coefficient into ASCE/SEI 41. An example is provided to illustrate the effect that the new coefficient has on the computed target displacement. For a 2% in 50 year motion at a San Francisco California site, application of the spectral shape coefficient results in a 40% reduction in the target displacement.

Tunnel and large cut-and-cover structure response to earthquakes is dominated by the surrounding ground, and, contrary to shallow-founded structures, does not depend on the inertial properties of the structures themselves. The focus of the underground design is on the free-field deformation of the ground and its interaction with the structure, i.e., a soil-structure interaction phenomenon. This paper summarizes the performance in recent past seismic events of deep, large underground structures, and then elaborates on their design approach: geotechnical, seismic criteria and structural factors. Analytical models are examined and conclusions drawn about their advantages and limitations. A general approach to the design of deep underground structures is illustrated through the on-going design of a particular project.

The Port of Anacortes, Washington is working on implementation of a complex clean-up project that includes excavation and dredging of contaminated sediment, capping the remaining sediment, constructing the detached attenuator, removing the old Port breakwater, and constructing a habitat and a pier for recreational activities. The complexity of the clean-up project is exacerbated by intense wave action and ongoing shoreline and bottom slope erosion. In order to determine a technically feasible and environmentally acceptable engineering solution for the clean-up project, the Port completed a comprehensive coastal engineering study that included extensive numerical modeling to evaluate wave action, tidal flow, and sediment stability. Based on results of the study, an optimal solution was found; preliminary and final engineering were completed; and environmental clearances were obtained. Project construction started in July 2009 and is scheduled for completion in March 2010. Copyright 2010 ASCE.

Waste paper sludge, or fiber-clay as it is often identified when used as a resource for recycling and reuse in new applications, has over the last several years become a vital component in several geotechnical uses and a variety of manufactured products. Among the major reuses of fiber-clay has been its use as a cover material for sanitary landfills, after thorough laboratory and field evaluations. Because of the high kaolin clay content in the manufacturing of paper products, there is a high residual of clay in waste paper sludge from the manufacturer's waste water treatment plants. The reuse of cover material has resulted in a cost avoidance for the waste generator, reducing or eliminating disposal costs as well as eliminating the need for finding a disposal site. There are also cost savings for landfill operator and owners who otherwise would have to secure an adequate clay source. When compacted, most fiber-clays exhibit adequate hydraulic conductivity and shear strength for use in landfill covers. In addition to its use as a cover material, the fiber-clay, when combined with a pozzalonic material such as fly ash and aggregate, has been used as one of the major components for road beds, both as subsurface base and as a finished surface for remote access and secondary roads. Additional uses include the manufacturing of kitty litter and animal bedding. This paper will review the history and technology involved in evaluating the potential uses of fiber-clay. Extensive laboratory and field testing has been done to determine its shear strength, slope stability, hydraulic conductivity, and settlement potential. Information is presented on the various testing techniques and results, together with examples of actual field projects.

Despite a great deal of interest in risk management of dams and water resource facilities during the latter part of the 20 th century, few opportunities to apply these emerging concepts arose in practice. This paper examines the fundamental principles of risk assessment and decisions concerning their management can not be carried out in the traditional way decisions concerning the safety of dams were made in the past. A framework for managing the risks posed by dams is presented as is a proposed approach to determining when risk assessment is appropriate, and the professional and societal structures and institutions that are required to permit implementation of risk assessment in dam risk management.

Widely varying material properties and joint configurations of the different pipe materials in common use have made it difficult to develop a coordinated thrust restraint design practice. This has resulted not only in significantly different guidance from AWWA design manuals for different pipe materials and agency requirements, but also widely varying design practices and company specific best practice approaches within the engineering community. Recognizing the need to develop consensus among practicing engineers as well as industry representatives and experts; in 2008, the members of the American Society of Civil Engineers (ASCE) Technical Committee on Pipeline Installation and Location formed a special task committee "Thrust Restraint Design of Buried Pipelines". The objectives of this task committee were: 1) To document current design practices of thrust restraint systems for various pipe materials; and compare current practices with theory. 2) To document the historical evolutions of the different design approaches, collect and compile field tests completed for different pipe materials. 3) To explore improvements to current practice, develop consensus, and propose recommendations for the development of a manual of practice. Since 2008, the task committee has prepared a white paper documenting the above objectives, held a workshop on thrust restraint design at the 2010 ASCE Pipelines Conference, and begun preparing a manual of practice (MOP) with the aim of improving and consolidating current practice into a more cohesive, if not universal approach. The task committee has also presented several papers at the last three ASCE Pipelines Conferences, documenting findings and progress. This paper briefly summarizes the progress by the committee since its inception in 2008, focusing on the progress made by the committee since the 2011 Pipelines Conference. It includes updates on the progress toward developing an analytical model for thrust restraint that is intended to form the backbone of the MOP. The analytical model will include factors that deal with: pipe-soil interaction including frictional and lateral resistance, pipe and joint flexibility, movement required to develop soil resistance and the limitations of joint materials, type and geometry on movement induced by thrust forces. Both thrust block and restrained joint methods are included. A simplified approach for common applications is also proposed.

This paper suggests a new theoretical lens to understand and manage construction design processes that draws on Heidegger’s theory of deliberate action (Heidegger 1963). The lens interprets the day to day activities of designers as being immersed in practice without deliberate attention to everyday actions. Being immersed, designers do not reiterate the initial problem context and will only design for initially dened criteria. Only if the day to day ow of immersed practice is interrupted or is breaking down designers will involve in what Heidegger calls \involved thematic deliberation" or \theoretical detached deliberation" (Sandberg and Tsoukas 2011) that allows them to reiterate the initial problem context. This early position paper, introduces this new theoretical lens and shows its value by analyzing a number of design episodes that I observed during my ongoing ethnographic research work with designers. The examples show that the new lens allows for a good understanding of the increasing problems of designers to identify the wide range of societal and engineering issues during post-modern construction design eorts upfront. I posit that this better understanding, in turn, will support the better management of the changing problem contexts that occur on almost all post-modern construction design projects.

Reinforced GCL samples from three different projects were partially pre-hydrated on native damp subgrade soils for several weeks, and were then tested for hydraulic conductivity using three real leachates under a variety of effective confining stresses. The samples permeated with MSW leachate were tested under effective stresses of 240, 480, and 720 kPa. The samples permeated with MSW-incinerator ash leachate were tested under effective stresses of 180, 360, and 530 kPa. The samples permeated with pulp & paper waste leachate were tested under effective stresses of 165, 340, and 475 kPa. All of the results showed decreasing hydraulic conductivity with increasing effective stress with the ash leachate being the most sensitive to effective stress, and the pulp & paper leachate being the least sensitive. The hydraulic conductivity of the GCL samples to all of the leachates tended to level off to a common value of about 2 x 10 –12 m/s at effective stresses above 475 kPa.

There are four major types of macro-evaluation on traffic safety traditionally adopted in China and overseas. However, as the number of influential factors of traffic safety increases, these evaluation methods are becoming less capable in practice. The introduction of Fuzzy Theory provides a new approach to this problem. This paper based on the traffic accident data of Shanghai and Suzhou has established a macro-evaluation model for assessing the safety performance of mixed transport modes, which include cars, motorcycles, gas motorcycles (LPG), electric bicycles and traditional bicycles. The model indicates that the safety performances of LPG, electric bicycles and traditional bicycles are much higher than that of cars and motorcycles. Electric bicycles and traditional bicycles have similar safety performances in the two cities. These findings set up a reference for the establisher of urban transport policies.

The maximum particle size of dewatered sludge from the quarry is 2 mm, with the water content of 24 - 25 %, the liquid limit of 38% and the plastic limit of 17%. It is usually disposed into the landfill. There is a possibility, however, in authors' mind, to recycle the dewatered sludge as a barrier material, because the soil with fine particles indicates a lower permeability providing appropriate compacted than the one with the coarse particles. In this study, firstly, compaction tests, CBR tests, cone penetration tests and permeability tests were conducted for the row dewatered sludge and the dewatered sludge mixed with crushed stone. As a result, it is found that the dewatered sludge mixed with crushed stones having a size between 5 and 13 mm at a ratio of 20 % in dry mass has the sufficient traffic ability and efficient coefficient of permeability as a barrier material. Then cutting geonets were added into the dewatered sludge mixed with crushed stones in order to prevent a shrinkage crack from progressing. Consequently the mixing ratio of 0.8 % of the cutting geonets is the best for preventing the drying shrinkage crack effectively.

This short paper presents revised information on the creep reduction factors used in the widely accepted method for geotextile mass per unit area design to prevent geomembrane puncture. The laboratory tests have been ongoing for 6-years and have not failed to date, leading to the tentative conclusion that published values of RF CR are quite conservative.

The expansion of the swelling clays when subjected to moisture increase can be simulated to a hidden cancer. Growth of tiny molecules composed of silica tetrahedral and alumina octahedral can reach a stage that causes harm to light structures. The cost of annual maintenance is estimated into billions of dollars worldwide. Extensive research was conducted to stabilize this problematic soil using chemical methods. Stabilization of swelling clays using lime or cement is a well known efficient chemical approach. Research works on optimum lime or cement content is established for many types of clay. The use of lime is more popular than cement due to its lower cost. However, the cement is found to be better in reducing the expansion and improving the soil strength. In order to optimize the improvement with a yet tolerable cost it is intended to investigate treating the clay using a combination of cement and lime. The previous research works carried out by other researchers indicated that the optimum stabilization lime content is expected between 3.5 to 5% of the dry weight of the soil. A research study conducted on Al-Ghatt clay shale focused on comparing the effect of adding a 4% lime content (The optimum content for lime only) with a lesser amount (2% by weight) consisting of cement and lime additives (1% lime and 1% cement). Stabilization of Al-Ghatt clay shale by using 4% lime reduced the swell percent by 3.3% in average. The use of 2% additive of cement and lime reduced the swell percent by 4.7% in average. The strength properties and bearing values were compared for the case of lime only and lime-cement additive. X-Ray diffraction tests were carried out for pure clay shale, clay shale with 4% lime additive and clay shale with 2% cement-lime additive. The effect on mineralogy is observed through the position and intensity of the peaks of common clay minerals. It is concluded that cement can be introduced with lime to achieve a better improvement with a reduced cost.

This study focused on the consolidation characteristics of two soils stabilized with class C fly ash (CFA), lime and plastic waste. Three groups of specimens were prepared: the first group consisted of specimens prepared with 10% class C fly ash and 6% lime and then cured for 28 days; the second set of specimens was prepared with recycled plastic waste with a plastic to soil ratio (PSR) of one; and the last group consisted of specimens prepared with raw soils and compacted at near optimum moisture content and maximum dry unit weight. The last group was considered a baseline to assess the effect of CFA, lime and plastic waste on the consolidation characteristics. Results showed that CFA, lime and plastic waste stabilization reduced the compressibility of soil. In addition, both the compression index (Cc) and swelling index (Cs) decreased due to CFA, lime and plastic waste stabilization. The percentage changes in Cc and Cs varied with the type of stabilizing agents.

This study presents the results of a treatability study for DM stabilization using fifteen combinations of stabilizing agents (lime, Cement Kiln Dust (CKD), fly ash). Two paste studies were conducted, both employing a mellowing period of up to 5 days under open and closed conditions, respectively. To illustrate the impacts of the different mellowing conditions on the characteristics of the stabilized DM, select physicochemical, geotechnical and mineralogical differences of the two sample sets are presented. Mellowing under closed conditions yielded non-compactable material for 10 of 15 blends, as the moisture content was too high. Conversely, open mellowing yielded compactable material for all blends as early as 2 days. The mineralogical analyses showed that cement reactions proceeded more slowly under closed conditions. Compaction curves generated for two blends under open and closed conditions yielded contradictory results in terms of blend performance, the higher densities being obtained under open conditions. Consequently, since open mellowing more closely resembles field conditions, it is recommended as a procedure prior to curing in future S/S paste studies.

This study uses lime and class C fly ash, an industrial byproduct of electric power production produced from burning lignite and subbituminous coal, to study the plasticity reduction in highly expensive natural clays from Idabel, Oklahoma. This study is important, especially in Oklahoma, because most of the native soils are expansive and cause seasonal damage to roadways and structures. The addition of lime or fly ash helps to arrest the shrinkage and swelling behavior of soil. Four soil samples with the same AASHTO classification were used in this study to show shrinkage variability within a soil group with the addition of lime and class C fly ash. The plasticity reduction in this study was quantified using the linear shrinkage test. It was found that soils classified within the same AASHTO group had varying shrinkage characteristics. It was also found that both lime and fly ash reduced the lienar shrinkage, however, the addition of lime reduced the linear shrinkage to a greater degree than the same percentage of class C fly ash. Even though it takes much less lime than fly ash to reduce the plasticity of a highly expansive soil, it may be less expensive to utilize fly ash, whichmore » is a waste product of electric power production. Lime also has a lower unit weight than fly ash so weight percentage results may be misleading.« less

The performance of bioflocculation and settling of activated sludges is a common problem for many treatment systems. According to divalent cation bridging theory, research has shown that cations are important in floc formation and subsequent settling and dewatering properties. Specifically, divalent cations (such as Ca 2+ and Mg 2+ ) have a positive impact on bioflocculation while monovalent cations (such as Na + ) can negatively impact bioflocculation. Therefore, the choice of chemicals used for pH control can significantly impact subsequent settling and effluent quality. The objectives of this research were to compare the impact of using either lime, Ca(OH)2, or caustic soda, NaOH, for pH control, and determine their effect on settling and plant performance of an activated sludge nitrification/denitrification system. The lime would control pH and also add Ca 2+ which should benefit settling, while caustic addition would add Na + to the solution which could potentially degrade floc properties according to the divalent cation bridging theory. Three laboratory scale reactors were constructed to mimic the five-stage, full scale Blue Plains wastewater treatment plant in Washington DC. Each reactor was fed effluent from the secondary treatment process and methanol was added as an external carbon source for denitrification. To maintain the pH, one reactor was fed lime (Ca(OH)2), one reactor fed caustic (NaOH), and one reactor was used as a control with no base addition. The reactors were operated for three solids retention times and monitored for effluent quality and treatment performance as well as floc and settling characteristics. In addition, microbial communities were analyzed using molecular techniques to compare the microbial communities in the lab and fullscale systems. The reactor fed with Ca(OH)2 generally had better floc characteristics as well as effluent quality in terms of soluble COD, effluent total nitrogen, and supernatant turbidity, and had greater stability. The microbial communities were compared using polymerase chain

ADAS (Automatic Data Acquisition Systems) are electronic devices used to automatically read, store and transmit measurements from geotechnical, environmental and structural sensors used for monitoring dams and levees. Because of the specificity of the conditions of their deployment in outdoor, spread-out and sometimes harsh conditions, ADAS used for those applications need to have a number of features and functionalities which are discussed in the paper. The paper will be limited to ADAS for monitoring static measurements, as opposed to systems for dynamic measurements such as accelerations due to earthquakes. Low power consumption, robustness, modularity, ease of deployment, diversified network configurations between units such as line , star and tree networks, a wide variety of telemetry options such as radio and cell modems are all features that are essential for a successful deployment in the field. The paper covers the features that are nowadays mainstream on available solutions for ADAS for dams and levee monitoring, including discussions on network configurations, power supply options, network access options and real-time monitoring. The advent of low-power low-cost radios that open the possibility of eliminating all surface cable runs on dams and levees is also discussed.

Sensitivity analysis involving different random variables and potential failure modes of cantilever sheet pile walls for different soil conditions focuses on the fact that, high sensitivity of a particular variable on a particular failure mode does not necessarily imply a remarkable contribution to overall failure probability (Pf). The present paper aims at identifying a probabilistic risk factor (Rf) for each random variable based on the combined effects of Pf of each mode of failure and sensitivity of each random variable on these failure modes. Three different soil conditions are considered: (1) cohesionless soil above and below dredge line, (2) cohesionless soil above dredge line and cohesive soil below dredge line and (3) cohesive soil above and below dredge line. It is observed that friction angle of both foundation and backfill soils are the major guiding factors for Case 1, while for Cases 2 and 3, cohesion for foundation soil dominates over the other two random variables. Thus the present paper proposes a safe and economic design by assigning different Rf for different random variables for sheet pile walls embedded in different subsurface conditions and varying positions of water table.

When estimating the time-rate of settlement for foundation soils treated with vertical drains, understanding the horizontal drainage behavior of the soil is important because the time of consolidation settlement may be critical to the overall construction schedule and sequencing. This paper explains the process for obtaining the horizontal properties of soft soils in the laboratory using a Rowe cell, a laboratory device that directly measures the horizontal drainage of soft soil samples through a radial consolidation test. The Rowe cell further allows for back-saturation of test specimens and the ability to replicate in situ lateral stress conditions with an applied cell pressure. This paper summarizes how challenges associated with specimen preparation, test setup and procedure, and data analysis and interpretation can be overcome. Finally, this paper demonstrates that this is a viable method that should be considered more often for obtaining horizontal drainage design parameters.

Ground-source heating of bridge decks can be an alternative to the use of salts and chemicals to deice bridge decks. Energy foundations, geothermal boreholes, shallow trenches, or the approach embankment can be utilized as energy storage media and heat exchange pathways to utilize the ground as a heat source. Coupling the energy foundation with a ground-source heat pump can provide higher inlet fluid temperatures and result in more effective bridge heating but at the expense of greater energy consumption and increased system complication. Circulating the fluid directly from the energy foundation to the bridge deck relies heavily on the in situ ground temperatures. This paper outlines the operational principles and how these are related to the design parameters of bridge-deck deicing systems. A series of parametric analyses was performed to investigate the bridge-deck heating process. The analyses considered a variety of tube spacings, inlet fluid temperatures (i.e., ground temperatures), flow rates, wind speeds, ambient temperatures, and thicknesses of concrete cover over the circulation tubes. The results serve as a benchmark to gauge the operational conditions and the energy requirements for designing ground-source bridge deck deicing systems. Ground temperatures serve as a baseline for heating of bridge decks with passive heating in the winter, and this study underlines its limitations at colder environments. This can be overcome by collecting heat from the bridge deck in the summer and injecting the collected heat into the ground to raise the ground temperatures. This stored energy can be reclaimed in the winter when needed. The issues related to heat collection and ground storage are part of a broader study and fall outside the scope of this paper.

This paper discusses the practical aspects of preparing Geotechnical Baseline Reports. Guidelines for the preparation of Geotechnical Baseline Reports were established in the ASCE publication entitled, “Geotechnical Baseline Reports for Construction,” dated 2007. However, the practical aspects of actually writing a Geotechnical Baseline Report and the risk assumptions associated with this document are highly controversial. Not every project needs a Geotechnical Baseline Report and not every geotechnical engineer is equipped to write one. This paper will provide its own set of guidelines for the preparation of Geotechnical Baseline Reports. The paper suggests that Geotechnical Baseline Reports are one contractual format for handling such as third party impacts and differing site conditions that often arise when involved with subsurface construction.

This paper describes a study of the behavior of a group of piles under impact loading. Many structures such as bridge piers, offshore platforms, or berthing foundations can be subjected to the horizontal impacts from ships during their lifetime in which the system failure would have serious consequences. Guardrails for road side safety are another type of impact-resisting system that are extensively used and have a direct relation to human life and cost. Moreover groups of piles can serve as an efficient and relatively cost-effective protective structure around critical and important facilities. Prediction of the system response during the impact can lead to a more effective and economical design. There has been a very limited amount of experimental work on lateral response of group piles under impact loading in particular in the field of full-scale tests. This paper describes a full-scale field test performed on a group of eight side-by-side piles embedded 3 m in a loose sand to sustain an impact of a 6800 kg truck with an approaching velocity of 80 km/h. The instrumentation includes accelerometers on the truck, strain gauges on the posts, and high-speed cameras to capture the deflection. The eight posts and the connector beam have been simulated using an advanced numerical simulation software LS-DYNA (Livermore Software Technology Corporation) to characterize the features of the soil-pile-beam interaction under impact and improve the design methodology.

Bridge scour is a major cause of damage to bridge foundations and abutments. Approximately 17,000 scour-critical bridges exist in the United States. Scour-critical bridges are bridges with foundations that are unstable for calculated and/or observed scour conditions. This designation comes in part from the use of overconservative methods that predict excessive scour depths in erosion-resistant materials. Other available methods capable of overcoming this overconservatism are relatively uneconomical because they require site-specific erosion testing. This paper presents the assessment of two bridge case histories using the observation method for scour (OMS). OMS is a relatively new quantitative bridge-scour assessment method that accounts for time-dependent scour depth using field measurements. This method, which does not require site-specific erosion testing, was developed as a first-order assessment method for use in combination with routine bridge inspections. OMS uses charts that extrapolate or interpolate measured scour depths at the bridge to obtain the scour depth corresponding to a specified future flood event. The vulnerability of the bridge to scour depends on the comparison between the predicted and allowable (threshold) scour depths. The case histories presented in this paper consist of two Texas bridges, one designated as scour critical and the other as stable by the Texas Department of Transportation (TxDOT). Both stable and scour-critical bridges were selected to test OMS and also compare it with TxDOT's scour designation. These case histories serve to demonstrate the validity and applicability of OMS to full-scale bridges and to provide practitioners with two potentially useful real-life case histories that could serve as examples for engineering practice. A validation process was performed on the two case histories using historical scour measurements and flow data. The validation exercise showed that there was good agreement between predicted scour depths using OMS and field measurements. OMS was then applied as a bridge-scour assessment tool to both bridges using the 100-year flood as the future flood and the outcome of OMS compared with the original TxDOT designation. As a result of this, the originally scour-critical bridge was found to be stable according to OMS. The bridge originally designated as stable was also found to be stable according to OMS.

In February of 2011 an earthquake event caused significant damage and loss of life in Christchurch, New Zealand. Such an event serves as motivation for improved foundation design and characterization of the shallow subsurface. In January of 2013, University of Texas engineers acquired surface wave data which has been made available to the ASCE GeoInstitute Geophysical Engineering Committee for a benchmark project. Participants were invited to process and interpret the common data set. This paper reports the results designated as those of “Analyst A”. The active vibroseis and sledgehammer data were combined to produce a composite Rayleigh wave dispersion curve. Alternative soil profile representations were considered. The resulting image is of low velocity zone sandwiched between a faster surface zone and a faster profile down to 30 meters depth. INTRODUCTION The UTexas1 SurfaceWave Dataset was acquired in Christchurch, New Zealand. The site was located approximately 1.5 km from the coast. The Geophysical Engineering Committee of the ASCE GeoInstitute has organized a benchmark project in which participating geophysical engineers have been invited to process and interpret this common data set with tools of their own choosing. The instructions were to work as much or as little of the data as each participant desired. The available data include both active-source and ambient noise sets. This participant has chosen to only work the active-source data. The vibrator data were processed in the frequency domain, the hammer data in the time domain. The resulting dispersion curves were then combined to provide a composite dispersion curve. Inversion of the composite dispersion curve was done employing a 1-D-gradational soil profile in which the objects of the inversion are control points whose depth and shear-wave velocity assignment may vary. The reader is referred to Michaels (2011) for another example of this representation. page 1 This is an author-produced, peer-reviewed version of this article. The final, definitive version of this document can be found online at Geo-Congress 2014: Technical Papers and Keynote Lectures, published by the American Society of Civil Engineers. Copyright restrictions may apply. doi: 10.1061/9780784413272.074

Over the past few years, intelligent compaction (IC) has been a focus of research, demonstration projects, and specification development in the United States. The Federal Highway Administration (FHWA) has recently moved IC to national level implementation. Equipment manufacturers, individual state departments of transportation (DOTs), and the Technology Transfer for Intelligent Compaction Consortium (TTICC), a Transportation Pooled Fund, TPF-5(233) initiative, are also focusing on implementation efforts. What this paper does is describe the results of a series of workshops attended by more than 400 attendees—representing several state DOTs, FHWA, equipment manufacturers, and researchers—that contributed to a detailed roadmap identifying implementation needs and action items. A key outcome of these workshops was the development of a prioritized list initially created in 2008 and updated annually through 2012. This paper describes in greater detail how this list was developed and prioritized and how it has changed since it was initiated in 2008. Accompanying this list is a set of action items to overcome the various barriers identified.

The use of drilled shaft concrete piles is generally not a widespread method of stabilization of landslides along Alberta highways as a result of perceived high costs and the uncertainty of performance of these structures in the long term. However, over the last 30 years, the use of drilled shaft piles has been the preferred method of stabilization of various sites where conventional methods were not feasible either because of site constraints or not considered appropriate. This paper presents a case history of a roadway embankment slide for which the most appropriate remedial measure was determined to be the use of a tie-back drilled shaft concrete pile retaining wall as a result of the deep-seated nature of the slide, inability to relocate the roadway, and concerns over using a toe berm. Stabilized in 1997, the roadway and pile wall are still performing satisfactorily despite some observed roadway undulations and movements of the sideslope behind the pile wall. This paper addresses the details of the site and slide activity, the judgments exercised in deciding the locations and depth of the concrete piles, and the design and construction of the pile wall retaining system.

The presence of groundwater table (GWT) within a flexible pavement can have a pronounced detrimental effect on the mechanical response of its foundations and consequently on the structural performance of the pavement system as a whole. The related literature reveals that little work was done to rigorously model the impact of shallow GWT on the pavement's structural performance and investigate the sensitivity of this impact to the foundation's stiffness. In this paper, statistical factorial analyses were applied to numerical modeling to investigate the effects of GWT, foundations stiffness, and GWT-foundation stiffness interaction factors on the rutting of flexible pavements. A finite element model simulating the pavement foundations as nonlinear porous media governed by the Biot coupled behavior was set up first. The response of the model was evaluated for combination of design values of the GWT and foundation stiffness parameters each of which was defined at lower and upper levels (two levels-factorial design of experiments). Analysis of variance (ANOVA) method was then used to examine the effects of the factors analyzed on the pavement rutting. The analysis results showed that the GWT and its interaction effect with subgrade stiffness have significant influences on the pavement rutting. The detrimental effect of the GWT becomes more pronounced when the subgrade stiffness decreases, while such effect changes insignificantly with changing the stiffness of the granular base. The paper opens a new window for assessing the structural performance of flexible pavements under various GWT and foundation material conditions using the coupled finite element method in conjunction with the statistical factorial analysis approach.

Geothermal piles are increasingly used around the world as an innovative and sustainable method of harvesting shallow geothermal energy. Energy harvested through this technique can be used to partially meet the heating and cooling energy demand for residential and commercial buildings. Despite the growing recognition of the benefits of geothermal piles, the complex heat exchange through these piles is not yet fully understood. This paper describes a series of thermal tests performed on an instrumented model heat exchanger pile installed in a standard F50 Ottawa sand bed. Temperature measurements were obtained at different locations within the soil, on the pile surface, on the tank boundary, and at the inlet and outlet points of the circulation tube. Recorded temperature data are used to obtain time-dependent heat exchange efficiency of the model pile. The thermal tests presented in this paper provide valuable data on the nature of heat exchange through geothermal piles and on the thermal response of soil in the vicinity of a heat exchanger pile.

Micropiles are small-diameter grouted piles (typically of diameters less than 300mm). Micropiles are ideally suited for low headroom and limited work area conditions. Specially developed installation processes mitigate noise nuisance, vibrations to surrounding soils and structures, disturbance to the production operations in individual units, and disruption to the functioning of business locality, which makes micropiles suitable for underpinning and seismic retrofitting of structures. With a wide variety of potential applications, it is necessary to understand the behavior of micropiles under different loading conditions. Reliable experimental data on battered micropiles are rather scarce compared with that of vertical micropiles. This paper presents the results from an experimental study conducted to understand the response of vertical and battered micropiles with different length/diameter ratio (L/D) subjected to vertical and lateral loading conditions. The vertical load-carrying capacity was found to increase with increasing L/D ratio upto a 300 batter. The ultimate lateral load was found to increase significantly with increasing L/D ratios up to a L/D ratio of 30 and 48 for vertical and battered piles, above which the increase in ultimate lateral load for increasing L/D ratios was found to be insignificant. Furthermore, the ultimate load capacity and mode of failure of the micropiles is a function of the angle of batter, direction of batter, and the L/D ratio for vertically and laterally loaded micropiles. The details of the experimental model employed in the study and the associated failure mechanisms are described in this paper.

Geothermal energy is an increasingly demanding energy source in Europe and USA. Louisiana has a huge potential for geothermal energy. This paper describes the potential use of geothermal energy which can be extracted in Louisiana. In the paper, a 4-story building was chosen in New Orleans, Louisiana, which has a pile foundation with a total of 145 driven piles. A total of 16 energy piles from 16 pile groups were simulated in the analysis, and it is found that each 24.38 m-long single pile can extract a maximum of 1.83 (kW/hr) cooling load and 1.68 (kW/hr) heating load. Altogether, the 16 energy piles can give almost 19.9% of the total cooling demand and 68.12% of the total heating demand of the entire building. Further analysis was also done to compare the economic and environmental effects by gas, propane, oil, electricity and geothermal energy to heat/cool the building. If the total demand of heating and cooling is done by each of these energy sources, it is found that natural gas will be 13.6 and electricity will be 16 times more costly than geothermal energy. Moreover, natural gas and electricity will emit 1.8 and 1.7 times more CO2 than geothermal energy.

This paper describes wisdom of ancient engineering practice. The first wisdom is about a biology-based method for bridge-scour protection. A number of historical bridges across waterways in China served for more than 1000 years without significant structural damages. Protection provided by cultivated oysters is believed to be responsible for their excellent performance in scour protection. This offers a green approach to mitigate bridge scour. Another story is about natural hazard warning. A number of historical records indicated that major natural hazards are typically accompanied by abnormal behaviors of animals. The first successful prediction of earthquake occurrence is the Haining earthquake of China. The prediction and evacuation order was partially based on observed abnormal behaviors of animals. The paper also describes an innovative sticky-rick lime mortar used in ancient construction and bio-inspired sensors that potentially can improve existing understanding of bridge-scour mechanisms. In the authors' opinion, these historical heritages will continue to inspire emerging engineering practice.

The concept and structural benefits of prestressing cold-formed steel beams are explored in the present paper. In the proposed system, prestressing is applied by means of a high-strength steel cable located within the cross section of the beam at an eccentric location with respect to the strong geometric axis. The internal forces generated by the prestressing are opposite in sign to those induced under subsequent vertical loading. Hence, the development of detrimental compressive stresses within the top region of the cold-formed steel beam is delayed and thus the load-carrying capacity of the beam is enhanced. Owing to the precamber that is induced along the member during the prestressing stage, the overall deflections of the beam are also reduced significantly. In the present paper, finite-element (FE) modeling was employed to simulate the mechanical behavior of prestressed cold-formed steel beams during the prestressing and vertical loading stages. Following the validation of the FE modeling approach, a set of parametric studies was conducted, where the influence of the key controlling parameters on the structural benefits obtained from the prestressing process was investigated. The parametric results were utilized to determine how the benefits obtained from the addition of the prestressed cable can be maximized, demonstrating the significant enhancements in the performance of the cold-formed steel beam that can be achieved.

Traditional paper-based methods for construction activity monitoring are inefficient and error-prone. In this paper, an automated approach is proposed for monitoring the progress of construction activities by tracking major construction equipment and bulk material, using sensor-based technologies. Data obtained from sensor-based technologies will be fused to determine the completed steps of the activities, and consequently to identify the overall progress of the activities. Also, human-generated data, such as daily site reports, will be used to support the sensor data. A rule-based approach is developed for fusion of the collected data. This paper describes the initial field tests that were performed to monitor the rebar installation activity at a pilot construction site. To collect data about the ongoing rebar installation activity, the embedded sensors (e.g., position and load sensors) of a tower crane anti-collision system, and the site reports and quantity takeoffs were used. Initial results show that the developed approach can estimate the progress of rebar installation activity with 98% accuracy.