Search

In the stabilization of gullies, small overflow dams are used to retain silt and to control the stream grade. These dams are simple drop structures similar to those used in irrigation canals. In this paper the development of rules for the proportioning of such dams is described in terms of the hydraulic requirements for structure performance. The formulas included in the design rules are presented graphically for convenience in application. These rules are based on the accumulated experience of engineers in irrigation and soil conservation work and on the results of a series of laboratory test programs.

In the state of Texas, the Texas Natural Resources Conservation Commission (TNRCC) establishes minimum sanitary sewer design criteria. The TNRCC provides criteria such as minimum slope, maximum manhole spacing distances, separation distances between water and wastewater pipelines, etc. All of these are elements of standard sanitary sewer design. This paper categorizes sanitary sewer design into that of development design and of rehabilitation design. Development design includes the installation of new lines and the connection of new services. Rehabilitation design includes the replacement/improvement of existing lines and the reconnection of existing services. Concerns of both design methods include that of alignment, construction, and material. The optimum alignment considers the present, future, and ultimate land use demands. The best construction method considers the minimal disruption to the existing land while providing a safe, cost effective, efficient way to install the pipe. The carrier pipe material considers the physical characteristics of wastewater flowing in it and the physical interaction with the surrounding environment.

In this paper, a system reliability-based load resistance factor design (LRFD) approach for the design of reinforced soil walls is presented to produce designs with consistent and uniform levels of risk for the whole range of design applications. First order reliability method (FORM) and series system approaches are used to determine appropriate ranges for the values of the load and resistance factors. Using pseudo-static limit equilibrium method, analyses are conducted to evaluate the external stability of reinforced soil walls subjected to earthquake loading. The potential failure mechanisms considered in the analysis are sliding failure, eccentricity failure of resultant force (or overturning failure), and bearing capacity failure. Partial factors needed to maintain the series system stability against three modes of failure by targeting a series system reliability index of 3.0 are obtained for six combinations of component reliability indices against sliding failure (βsli), eccentricity failure (βe), and bearing failure (βb). The load and resistance factors are proposed for a 6.0 m high wall for various values of coefficients of variation (COV) of friction angle of backfill and horizontal seismic acceleration coefficient.

This paper discusses new approaches for modeling the social impacts of lifeline losses in disasters. It focuses on two types of impacts: displaced persons (and associated demand for public shelter), and reduction in functionality of health care facilities such as hospitals. The models are applied to Los Angeles. The shelter model simulates households' decision-making and considers socio-economic and locational factors in addition to housing damage and lifeline loss. It performs well in simulating the Northridge earthquake. In a M6.8 Verdugo Fault scenario, with much higher building damage and lifeline outage durations, as many as 212,000 households are estimated to seek public shelter. Accounting for lifelines substantially raises estimates compared to considering building damage alone. The health care model draws on empirical data to model the operational performance of a hospital's interacting systems (structural, nonstructural, lifeline, and personnel) in an earthquake. Results for Verdugo indicate that nearly half of L.A. county hospitals have at least a 50% chance of experiencing significant loss of functionality. The contribution of regional lifeline disruption to this loss is fairly small.

In this paper the author describes an experimental attempt to prevent the rapid blocking of a harbor entrance caused by littoral drift in the summer period. This work was conducted at "Seppu", a fishing harbor constructed on a sandy beach in Hokkaido, Japan. This investigation was originally sponsored by the Harbor Section of the Hokkaido Prefectural Office One of the top priority objectives, at that time, was to determine the efficiency of two jetties constructed on the updrift side for the purpose of countering the sand drift. Detailed observations including preliminary model experiments, were made from 1961 to I963 on the general aspects (ie condition and phenomena) of the coast in question. Meteorological data were also compiled together with investigations as set forth by the government. Based on the above, the author finally suggested the utilization of natural forces ie waves, offshore currents etc, by constructing an offshore breakwater to curb the blockage of the harbor mouth. This idea was shown to be adequate at least qualitatively by model experiment with the exception of the troublesome time scale problem. These findings, however, have not been adopted as yet for actual improvement of the harbor at present.

The Nagoya Storm-Tide-Preventing Breakwater is a large-scale Breakwater built as a link in the general Ise Bay Storm-Tide-Prevention Project. The entire length of this breakwater is about 8,250 meters, which extends from the mouth of the Nabeta River, transversing the northern part of Ise Bay, to the Chita town. (Pig. 4) The greater half of this breakwater was built on an extremely unstable foundation, the nature of ground being of soft clay stratum with a thickness of 10 m - JO m. The sand-drain method was adopted for improving the ground on which caissons were laid, forming a composite type section. For this reason, during the process of construction a close work control was maintained constantly by applying boring, observation on the sinking, pore water pressure and other conditions to ascertain whether the sinking by consolidation took place according to the calculations laid in the design specification. Based on the date obtained in this manner the speed of the work was regulated and the work was conducted under strict control of soil mechanics. The required volume of materials for the construction of the breakwater was so immense that a special care had to be given to ensure their smooth and efficient supply. And to speed up the work with a view to reducing the effects of wind and waves to a minimum, large machinery were employed. The present paper describes the engineering features of this great 8,250-meters breakwater project which was completed in a short period of 2 years and 8 months at a cost of 30 million dollars after overcoming numerous obstacles.

Intercity travel has been on the rise in the last few decades, resulting in severe congestion on intercity freeway corridors. Existing modes such as air, rail, and bus services have respective limitations and have not been effective in alleviating the present and future intercity travel challenges. "Flexpress" is a flexible and high-speed intercity transit service that is conceived and designed to accomplish three major operating characteristics: high speed, high capacity and high accessibility. It is a 20-passenger tire-based electric vehicle that is equipped with CACC (cooperative adaptive cruise control) technology to virtually chain up with vehicles of the same type, forming a self-driving high-speed platoon on a dedicated guideway. Upon reaching an urban area, this platoon breaks up into individual vehicles driven by human drivers, and each vehicle heads to a different terminal, bringing passengers closer to their final destinations. This paper presents the concept and service design of Flexpress as well as some preliminary findings from a demand analysis that in addition to provide individual preferences, help investigate the overall potential market in the U.S.

This paper is a sequence to two papers, (1) and (2), previously read at Coastal Engineering Conferences. They presented a mathematical model for estimating displacements, velocities and accelerations in a downrushmg wave on a rubble mound breakwater slope. Verification by photographic recording of displacements involved some uncertainties. In the present paper are reported measurements of velocities, which gave much more definite data. The correlation with velocities calculated from the model is shown to be good.

The characteristics of oscillatory boundary layer flow have been treated with keen interest during the last decade from the various aspects. Among the previous results the theoretical treatment by K. Kajiura must be the most important and fruitful one to advance in our knowledge on the present phenomena. On the other hand the senior author has had a real interest in the behaviour of sediment particles due to oscillatory fluid motion, and has conducted his systematic investigations on the sediment movement in nearshore area. The aim of this paper is to introduce some results of the recent investigations conducted at the Coastal Engineering Laboratory, University of Tokyo, with the intention of investigating the applicability of Kajiura's theory to the oscillatory flow in the vicinity of bottom with sand ripples.

This paper is a factual account of studies carried out for the design of a new deep water harbour. As so often happens, construction work had to begin before many of the conclusions of the study were available, so that alterations to the initial designs had to be made while work progressed. The studies comprised tidal and wave recordings and analysis, model studies to determine residual wave conditions at the quays, studies to determine the extent of littoral drift, the effect of the proposed works upon this and possible measures to counter downdrift erosion. In addition, studies were made of the stability of the adjacent creek channel which had previously been the harbour and a mathematical model study was carried out of the effects on the creek regime of various proposed entrance works, including the construction of an entirely new creek entrance channel through the new deep water harbour.

The wave program described in this paper is one intended to provide wave statistics by having our Los Angeles County life guards observe the wave heights, directions and periods. Mark-sense cards and high speed data processing equipment and computers are used to handle the volumes of statistics. While some scientists are planning very accurate, costly solutions to the problems of wave statistics, agencies are reluctant to venture into an expensive, elaborate wave surveillance program requiring a large quantity of personnel. I feel that neither the accuracy of present day design or construction methods warrant "split hair" accuracy in wave surveillance. The method described in this paper will provide a practical solution if the statistics are handled as follow 1. Wave statistics are gathered continuously over many years of time. 2. A standard is set to check the observed values. 3. Large rare damaging storm conditions will be developed by any reasonable means available until enough years of observation have passed to provide adequate statistics.

The general problem of single-impulse induced waves has been under experimental investigation by the author for several years The present paper is confined to a presentation of the wave modes which are to be expected for various permutations of displacement velocity and displacement length at the impulse source Other portions of the study will be published elsewhere It is clear that a number of geometric arrangements in the laboratory may be made to generate impulse waves, for example, sudden upthrust or downdrop of a block on the tank bottom analagous to block faulting on the sea-floor in nature, or a hinged flap moving on the bottom analagous to the undulatory bottom motion which may occur during seismic disturbances on the sea floor However, it is my opinion that the impulse generator which is most simple and most easily related to contemporary generalized theory, is a single piston thrust at one end of the wave tank which pushes the fluid down channel (See Figure 1) As an additional simplification, the investigation is carried out for the flat bottom, fixed depth case, relegating the effect of varying depth to a later study.

This paper summarizes the results of a continuing study at the hydraulic laboratory at the University of California at Berkeley on this subject, which is supported by the Coastal Engineering Research Center (CERC) and which has resulted over the years in the Theses of Huon ti (1954), M. Manohar (1955), G. Kalkanis (1957, 1963), M. M. Abou-Seida (1965), M. M. Das (1968) and is at this time being continued by T. C. Mac Donald. All these researchers have greatly contributed to the success of this work while the author was mostly responsible for the continuity of the study. The aim of the study was to see if it is possible to establish for the description and prediction of sediment transport by waves a general system of approach similar to that which the author published in 1950 under the title '.'The Bed-Load Function for Sediment Transport in Open Channel Flows". ( It was hoped at the time that many of the basic steps of such a description may at least be similar to those used for uni-directional flow. It became apparent that such similarities of approach were quite feasible; but another difficulty became apparent from the beginning. While in the uni-directional flow many details of the flow, such as velocity distributions, boundary layers and turbulence had been, studied and described previously, such knowledge was almost entirely lacking for wave motion. The first part of the study consisted entirely of hydraulic measurements and of their analysis. In order to determine the necessary scope of such hydraulic studies, the analogy with sediment transport in uni-directional flow was used. Some of the principles governing uni-directional flow transport are: 1. Sediment motion can be divided into bed-load motion or surface creep and suspension. 2. While moving as bed load, the particle weight is to a large part transmitted directly to the nonmoving bed, not to the flow. 3. The rate of bed-load motion is defined by the equilibrium exchange of sediment between the bed-load and the nonmoving bed. 4. This equilibrium gives a direct relationship between the sediment rate and the flow conditions near the bed, including the turbulence. 5. The flow condition near the bed can be predicted for a uni-directional boundary layer as a function of the bed shear and the bed roughness, only.

The Canadian Organizing Committee, the Vancouver Executive Committee and the National Research Council of Canada have done a superb job in planning this conference and in carrying out the enormous amount of detail necessary for its realization. On behalf of the Coastal Engineering Research Council, the other participating organizations, and all of the attendees I thank most heartily all who participated in this work. I am personally most grateful to those representatives of the Canadian Committee who made the final selection of papers. I should explain at this point that a small papers Committee is appointed for each of these conferences to review the summaries submitted by the authors - but this screening is intended only to appraise their appropriateness for a coastal engineering audience - and to eliminate those few papers which are promotional "blurbs". It has not been a technical review such as is made for "refereed" technical and scientific journals. The number of papers submitted for this Conference passing this simple review far exceeded the reasonable limits of the program - and for a brief period the Papers Committee faced the new and distasteful task of selection among papers acceptable under past standards. However, the problem was handled by the Canadian Committee - applying a formula which seemed equitable and reasonable. I trust that those affected concur in this judgment.

The rubble-mound seawalls, groins, breakwaters and ripraps around oceanfall pipelines are still the most common type of shore-protection structures currently in use. Major reasons include: easiness to construct and repair, flexible with respect to settlement, favorable wave-energy dissipation, fitness for any water depth and any foundation, and because of its economical nature if rubble-stones are readily available. However, the importance of a filter system in the stability of such structures must be emphasized. More recently, the submerged rubble-mound structures have become very popular due to aesthetic reasons. A filter system is considered a must to protect such a structure against erosion as a result of wave overtopping. Following a brief review of the problems, general discussions are made of the specific causes of failures including piping, overtopping, and nonstability. The physical factors that would affect the filter design are discussed in detail. Methods for design of filter system is presented including those applicable to the gradation of filter layers and to the plastic filters. The design procedure involves (a) making mechanical analysis of the backfill and base material, (b) estimating sizes of voids in the rubble-stones, (c) designing filter by Terzaghi criteria as revised by U.S. Army Waterways Experiment Station. A sample design of graded filter system behind rubble-mound seawalls is given. The procedure for the selection of plastic filters is also included. A comparison of the merits and demerits of these two types of filter systems will be made. This comparison will take into account the model test results conducted in the Look Laboratory. However, the readers are cautioned about the scale effects of the scour characteristics particularly on those tests with light-weight model sediments. This paper is intended as a general guideline for practicing engineers who will be responsible for design and construction of rubble-mound marine structures.

A compaction quality control (QC) in highway construction in Thailand is typically based on an in-place density measurement using the sand replacement method. Although monitoring compaction quality through a sand cone density test is relatively simple, such method is generally time consuming, labor intensive, less cost-effective, and destructive. This paper presents the laboratory evaluation of an innovative QC tool called the soil density gauge (SDG), which provides rapid and instantaneous measurement of density and moisture content based on the electrical impedance spectroscopy. The SDG was evaluated in a test box. Six highway materials were used in the study. The variation of SDG measurements along with its measurement characteristics was investigated herein. The paper also compared the SDG density and moisture content measurements with other tests such as the nuclear gauge, the soil stiffness gauge, and the sand cone method etc.

The paper deals with two-dimensional tests on a scale model of a dolos breakwater. It is related with the construction of a large harbour at Sines for tankers with up to 1 million dwt, ore ships with up to 300,000 dwt, general cargo, etc. The main breakwater is design ed with 40 t dolos, in order to withstand waves with up to 1 1 m significant wave height(100 years return period). Considerations on wave data and on modelling the spectrum ( Pierson-Moskowitz ) precede the presentation of three sets of tests on LNEC's irregular wave flume. Main results are compared with those from regular wave tests. The most important conclusions are stressed: influence of pla_ cement on dolos damages, irrelevance of maintenance, importance of the singular zone of the dolos support base, disadjustment of Hudson's formula for calculation of dolos weight using H as significant wave height,and importance of individual movements for the risk of breaking of individual blocks.

The wave-pressure formulas derived in our laboratory have been verified by the investigations of the slide of the vertical walls of composite-type breakwaters due to severe waves during heavy storms which have attacked numerous harbors in Japan since 1959. Some of the examples are shown in this paper.

Beach erosion is one of the serious problem in Japan. As a countermeasure against beach erosion, many preventive works, such as sea walls and groins, have been constructed during the past 20 or more years. However, as the result of field investigations, it has become clear that sea walls and groins are not always effective on beach erosion prevention, and inversely, in some cases, they accelerate the beach erosion. Based on the above cognition, the author has proposed and tried to apply the detached breakwater system as a measure against beach erosion for the last 8 years. This is for the purpose of developing the sand deposition behind the breakwater. Therefore several experimental works of the detached breakwater system were carried out under the guidance of the present author, and most of these tests were successful. The design method of this system was composed by the author on the basis of the result of field investigations, which have been conducted for more than 8 years. The numerous construction works of detached breakwaters have been carried out in accordance with the design method proposed in this paper, and the effectiveness of detached breakwaters has been proved on the several coasts in Japan where severe beach erosion occurs.

SUMMARY: The intelligent jobsite is becoming a reality as applications using sensors and mobile computing devices are being developed and deployed commercially. This creates an opportunity for workers to access data in an ad hoc manner as they move through a site. However, retasking and reuse of sensors in a dynamic setting presents significant challenges including ad hoc identification of sensors in a local environment, generalization of data, and the use of dynamic information for decision support. To achieve a generalized approach to using local data, we describe an architecture that abstracts functionality into three tiers: a layer for physical communication among devices; a layer for data processing and abstraction; and a top layer for decision support. At each tier, the level of abstraction increases, allowing for development of decision support applications at the top level that are not directly tied to specific devices. The industry vision for the intelligent jobsite is driving considerable research and development in mobile technologies. However, the bulk of this development is application specific and directly ties hardware (e.g., RFID tags, sensors) to data processing applications. We seek to decouple sensors from computing hardware and application development by providing a flexible and robust middleware. Realization of the middleware will enable more flexible reuse of data to make it available to a range of decision support applications, while at the same time speeding development of such applications. This paper describes an architecture informed by a working first generation prototype. Details of the prototype, lessons learned, and specific advancements are detailed. Future commercial implementation of the architecture will make construction-specific visions for ubiquitous computing possible by enabling flexible and robust discovery and use of data in an ad hoc manner.

The paper describes investigations carried out in order to design for the wave action, both wave force and scour, on large off-shore berthing structures sited approximately 1.3 miles (2.1 km) off-shore near Hay Point, North Queensland, in 56 feet (17 m) of water at low tide, the tidal range being 20 feet (6 m). The region is a cyclone area and the structures must be capable of withstanding attack from maximum predicted waves with period of 8.25 seconds and amplitude of 24 feet (7.3 m). The main units in the berthing structures are concrete caissons sunk on to the ocean bed and the largest of these have plan dimensions of approximately 150 feet (46.7 m) by 135 feet (41.4 m) with four columns approximately 40 feet (12.2 m) square projecting through the water surface. No theoretical method available at the time of the investigation was capable of accurate calculation of wave forces on these structures. A scale model was tested to obtain wave forces and the paper compares results from the model with those of numerical methods and discusses the application of the results to the design functions. Scour effects were also modelled and the results used as the basis for design of scour protection.

Some available data on wave overtopping by monochromatic waves were reevaluated before publication of the Shore Protection Manual (U.S. Army, Corps of Engineers, Coastal Engineering Research Center, 1973). The analysis of earlier data was made in order to summarize and present it in a more readily usable form. This paper provides empirical equations which can be used to predict overtopping rates for various structure slopes and structure types if accurate predictions of runup are available.

The objectives of this paper are two-fold: a. Demonstrate by means of a well-documented full-scale case history in the Great Lakes that beach nourishment can mitigate shore damage due to a littoral barrier; b. Detail a methodology for analysis of the effectiveness of mitigation measures which lead to conclusions on the needed frequency of nearshore soundings as a tool for monitoring. In 1970 a temporary harbor was installed by private interests along the southeastern Lake Michigan shoreline near Bridgman, Michigan, (Figure 1). The harbor was necessary to protect floating plant involved in building a large privately-owned electric generating facility. The harbor was constructed of steel sheet pile and extended lakeward about 125 meters from the water's-edge to a depth about 3 meters below low water datum (LWD)2. Net littoral transport is about 75,000 cubic meters per year southward. The updrift and downdrift lakebed and bluff materials consist of sand. To ensure that this littoral barrier would not have an adverse effect on adjacent properties it was necessary for the Corps of Engineers to impose stringent requirements for issuance of a Federal permit for the installation. Bypass of at least 75,000 cubic meters per year of sand was required to mitigate potential erosion of downdrift beaches due to interruption of littoral transport. The permit also required intensive monitoring of the shoreline to ensure that any adverse effects of the harbor would be promptly detected and remedied. The monitoring consisted of: a. Monthly 1:3000 scale aerial photographs of the shoreline sixteen kilometers north (updrift) to sixteen kilometers south (downdrift) ro\-fF tthheo htla'i rVtbt-lof\rv>. b. Monumenting and thrice-yearly measurement of backshore-nearshore profiles spaced 150 meters apart, for a distance of 2450 meters north and 2450 meters south of the harbor, extending about 900 meters lakeward to about -8 meters LWD (Figure 2). The nearshore soundings were made by acoustic sounder every 30 meters along each profile. The survey boat was located along the profile by triangulation. Backshore profiles were provided by photogrammetric mapping.

The ability to measure the wave spectra in the open ocean from a moving vessel has met with varying degrees of success. Each sensor to date has suffered in its performance due to environmental conditions or due to its physical placement aboard the vessel for measuring the unperturbed sea. This paper will discuss the utilization of a microwave sensor on a moving vessel for measuring the open ocean wave spectra. Employing microwaves, some of the limitations of other sensors are not experienced. Tucker [1] developed the Tuckermeter for measuring the wave spectra from a moving ship by sensing changes in water pressure due to surface wave conditions. The Tuckermeter is placed below the water line and thus requires calibration for each wave frequency, ship speed, and depth. Since the sensor operates on pressure, it performs as a low pass filter and will not sense the higher frequencies. A microwave shipboard wave height radar sensor for measuring the ocean wave spectra was developed by the Naval Research Laboratory (NRL) and was installed on the S.S. McLean in February 1975 and its performance, design, and analysis of data for one data run will be discussed.

This paper describes the results of an experimental study on the effect of waves on rubble-mound breakwaters, wave transmission subsequent to wave overtopping, the stability of the three sides subjected to wave action and the effect of the breakwaters on waves. Two different rubble-mound breakwaters were tested, i. e. one with a rigid impermeable crest and the other with a flexible permeable crest. Tests were performed with both regular and irregular wave train systems. To obtain the simulated irregular wave trains, four theoretical spectra were chosen: Neumann, Bretschneider, Moskowitz, and Scott. Results obtained from tests with irregular wave trains were compared to those obtained from tests with regular wave trains. It was found that more information was obtained on the behaviour of the structure when it was submitted to the attack of irregular waves than when submitted to regular waves, and that the use of irregular wave trains gave more interesting results.

Previous publications resulting from this study dealt with, certain aspects of the interaction of normally incident waves with a porous structure. Madsen and White (1976a), hereafter referred to as (I), developed a semi-empirical procedure for the prediction of reflection coefficients of rough impermeable slopes. Madsen (1974) with, discussion by Kondo (1975) and Closure by Madsen (1976), collectively referred to as(ll)hereafter, developed an explicit solution for the transmission and reflection coefficients of homogeneous rectangular crib-style breakwaters. When viewing the interaction of incident waves with, a trapezoidal, multilayered breakwater as a problem of energy dissipation, the problem treated in (II) may he regarded as an idealized analysis accounting for the internal dissipation of energy within the structure, whereas (I) may be regarded as an idealized analysis of the energy dissipation on the seaward face of the breakwater, i.e., the external energy dissipation. The present paper presents a synthesis of the results obtained in (I) and (II) into an approximate procedure for the prediction of wave reflection from and transmission through trapezoidal, multilayered breakwaters. The present paper presents only the major points of the approximate procedure. Thus, extensive references to (I) and (II) are made and only the determination of the hydraulically equivalent breakwater is presented in some detail. For a presentation of the entire development of this model for the reflection and transmission characteristics of trapezoidal, multilayered breakwaters the reader is referred to Madsen and White (1975) or Madsen and White (1976b) where detailed numerical examples of the use of the procedure may also be found.

The objective of this paper is to present statistical analysis of unbound subgrade pressure measurements. A heavily instrumented, flexible pavement was constructed and received an uncharacteristically low amount of rainfall for several months thereafter. The large amount of data acquired under the relatively constant moisture conditions during this period served as an excellent tool to analyze variability form a full scale pavement test, especially in the context of measurement redundancy and appropriate analysis techniques. The analysis presented in this paper focuses on measured subgrade pressures and is part of a more comprehensive effort to assess all pavement layers. It was shown that sensor redundancy alone may lead to erroneous conclusions if the redundancy is taken as a substitute for variability analysis. Future work aims to demonstrate optimal techniques useful for generating meaningful conclusions by incorporating sensor redundancy, measurement variability, and construction variability.

In many applications there is a great need for a correct description of the natural, irregular three-dimensional sea and its reproduction in physical and numerical models. Because of the tremendous difficulties inherent in the nonlinearities, the science of coastal engineering is still very far from this ultimate goal. Indeed, the scope of this paper is comparatively very modest: To describe and reproduce natural, irregular two-dimensional waves, i.e. waves propagating in one direction in a flume. In addition, this scope is fulfilled only by assuming linear superposition of Fourier terms. As opposed to the usual spectral description, the deterministic description presented here does not eliminate the phase information in the wave train recorded. Because of the nonlinearities, however, the linear deterministic description invariably degenerates with the distance travelled by the waves. It appears though from the present paper that the degeneration is fairly slow even for rather steep waves.

Submerged breakwater is a barrier with its crest at or slightly below the still water level. In situations where complete protection from waves is not required, submerged breakwaters offer a potentially economic solution. Submerged breakwaters have been effectively used to protect harbour entrances, to reduce siltation in entrance channels, against beach erosion, and for creation of artifical fishing grounds. However quantitative information available about the hydraulic behaviour of these submerged breakwaters is rather limited. Theoretical analysis of the problem has not proved satisfactory primarily because of the difficulties in quantifying the energy losses that always accompany these wave - structure interactions. Recourse has to be taken to laboratory studies to provide the necessary information regarding the performance characteristics of submerged breakwaters. A comprehensive laboratory investigation to evaluate the performance characteristics of the submerged breakwaters of various types and shapes, permeable and impermeable was undertaken. The results of these investigations are presented in this paper.

This paper presents results of an experimental investigation to increase roughness within the barrel of a concrete box culvert using trapezoidal-shaped corrugations with a shape similar to pavement underlay on bridge decks. Half-scale corrugations were placed on the bottom and both sides of a tilting flume 21 meters long, 0.90 meters wide, and 0.53 meters deep in Albrook Hydraulics Laboratory at Washington State University. During the experiment, wood cut to the shape of bridge decking simulated the concrete forms expected to be used in the field. Experimental flow rates ranged from 24–144 L/s. Experimental slopes ranged from 0.3–10.1%. Depths were measured with a point gage in several points upstream of corrugations, within the corrugations, and downstream of corrugations. Depths were measured at both the crest and the trough within corrugations. Manning's n was found to be dependent on the submergence ratio in a power function. In a range of submergence ratios between 1.33 and 3.0, the Manning's n ranged from 0.03–0.05 after scaling to full size. This increase in Manning's n would lead to a 40–60% velocity reduction in full scale conditions.

Advanced Energy Retrofit (AER) projects can significantly reduce energy consumption of existing buildings, and studies have indicated that they can be more economic than constructing new building. Retrofit projects vary in complexity based on the building characteristics, building area, client requirements, project budget, payback period and energy savings targets. The lack of a transparent and streamlined integrative process makes it difficult for the participants to implement AER projects. To implement comprehensive AER projects (also known as Deep Retrofits) in an efficient manner, it is important to understand the process along with the information exchanged during the planning, design, construction and operation phases. This paper describes the development of an AER integrative delivery process model with a focus on the planning and design phases. The integrative process has been developed through a detailed literature review, and studying the project documents and procedures used to deliver an ongoing comprehensive AER project. It was validated by review in multiple industry workshops, and through interview with industry and academic experts, including all the primary team members of a comprehensive AER case study. The process is undergoing additional validation through AER integrative workshops and a detailed case study analysis. The final integrative process includes activities focused upon specific building systems along with integrated processes and information exchanges, which support the integrated workflow among team members. The identified important information exchanges outline a series of exchanges that support application interoperability for AER projects.

Between October 1976 and July 1977 a northern rubble mound jetty was constructed at the mouth of the Hastings River, transforming the entrance from a single to a double jettied system. Prior to the jetty construction the entrance was characterised by the presence of a substantial swash bar (alternatively called an ebb delta marginal shoal) which was a continuous feature over 100 years of hydrographic survey records. However, construction of the northern jetty triggered an unprecedented onshore movement of the swash bar. This movement was well documented by a field monitoring programme incorporating hydrosurveys, aerial* photographs, tidal gaugings, sediment sampling, float tracking and nearby wave rider buoy information. A semi-quantitative model was developed to aid understanding and quantification of the macro sedimentary processes associated with this phenomenon. The model demonstrated that the sudden reduction of the swash bar was due to the disruption of a circulation of sand which had previously aided the dynamic stability of the bar. The quantitative predictions of the model agreed well with subsequent entrance behaviour. The philosophical development of the model and its findings are discussed in detail. In the literature there is a general lack of attempts to quantify the sediment transport relationships between the gross morphologic features of tidal entrances. This paper presents a methodology for assessing the sedimentary process at tidal entrances.

Some of the factors involved in the design of a programme of measurement and analysis of current, temperature and salinity data, required for the environmental assessment of an estuarine port, are considered in the context of a study carried out in the Port of Melbourne, Australia. The study was undertaken as part of the Port of Melbourne Environmental Study, 6 Webb Dock Marine Study which was aimed at assessing the present regime and the effects on the marine and coastal environments resulting from the construction of Berth 6, Webb Dock in Hobsons Bay (Figure 1). To this end, integrated investigations of water movement, water quality, coastal processes and marine ecology were conducted. Although the results presented in this paper are specific to Hobsons Bay, the approach taken is of general applicability to the environmental assessment of proposed physical changes in complex estuaries and embayments. In such cases, the prediction of changed patterns of currents and density structure is a key element in assessing likely changes in other environmental factors such as water quality and the biota. In general, an environmental study of water movement in an estuary will involve some measurements of the existing conditions of current, temperature and salinity, followed by appropriate analyses of these data to enable the likely changes to be predicted.

This paper describes the analytical and experimental studies on the behaviors of a ship subjected to a sheering flow induced around a rectangular solid-type marine structure, and also deals with ship-structure protective systems against ship impacts. Large bridge piers, which are constructed in a narrow waterway with strong tidal currents, are treated herein as one of the typical solidtype marine structures.

The construction of the New Oil Port in Dalian, C.P.R., was started at the end 1974 and completed in autumn 1976. In this paper, a summary of the essential considerations in the design and construction of this oil port, such as the planning of the pier, the determination of exciting forces (namely wave forces, forces due to earthquake, mooring line forces and berthing forces due to the impact of tanker on the fenders) on structures is presented. Also presented are the design of the large cylindrical caisson with a diameter of 9m and a height up to 19.7m, and the construction of two types of connecting bridges.

Seismic deficiency of Success Dam, California has been determined and the need of remediation for improving the performance of the dam under earthquake loading has been identified. Consequently, the dam is currently operated under reservoir pool elevation restriction, pending rehabilitation implementation. Justification of operation restrictions and establishing the priority of remediation activities required preparation of a baseline risk assessment. This paper describes the overall risk model and the results of the risk assessment supporting the justification of operation restrictions. Two companion papers describe the potential failure modes related to earthquake events and flood events. PROJECT DESCRIPTION Lake Success has been operated by the Sacramento District of the US Army Corps of Engineers (USACE) since completion of construction in 1961. The project comprises the dam, the Frazier Dike and a reservoir located on the Tule River about 10 km (6 miles) east of Porterville and 72 km (45 miles) north of Bakersfield, California. The reservoir captures runoff from a 1,013 km (391 square miles) mountainous watershed. It is part of a system of reservoirs that provide flood protection to the Tulare Lakebed and adjacent areas. It also provides irrigation water storage and recreation benefits. Success Dam is a compacted earthfill embankment dam 44.2 m (145 feet) high, 1,038 m (3,404 feet) long and with a crest elevation of 210.8 m (691.5 feet) as shown in a companion paper by Anderson et al. (2011). The dam has a central core of sandy clay and clay, and a pervious shell. The shell material is protected by a 3.7 m (12 feet) thick transition zone, which partially meets modern filter criteria between the core and the transition material and between the transition material and the pervious shell. There is a cutoff trench under the core that extends through the recent alluvium to either bedrock or in some cases to an older alluvium stratum. The recent alluvium was not excavated in the area beneath the pervious shell. Shear wave velocity measurements and standard penetration tests in the recent alluvium and the upstream and downstream embankment shoulders indicate that these materials are loose and could be subject to liquefaction during an earthquake. 586 GeoRisk 2011 © ASCE 2011

As appurtenance of existing building drainage systems the septic tank may be the single most important component used in the onsite treatment and collection alternatives. The passive - energy free - septic tanks provide the most cost efficient form of primary treatment available for nonindustrial sewage. Because the septic tank is an essential ingredient to the success of building drainage systems and a failed septic tank can present major inconvenience and pose a serious health threat as well as are failing to adequately protect the environment, it’s engineered design, practical application and maintain addresses the central problem. In this paper the existing problems of the septic tank system currently using in China are summarized by means of field survey and investigation. Also via the field experiments, the treatment efficiency of CODcr has been made an appraisal. The application of the computer simulation to analyze of sewage flow characteristic inside the septic tank is clearly described. Afterwards, some new ideas and methods are presented in order to improve the performance of existing system.

Since 1957, the State of Florida, U.S.A., has witnessed the evolution of coastal regulatory concepts based upon coastal engineering design guidance. In 1978, the Florida Legislature encouraged counties and municipalities to adopt coastal construction zoning and building codes to supplement the existing minimum codes which include the Standard Building Code, the National Building Code and the South Florida Building Code. Subsequently, coastal building code guidelines were developed to provide statewide uniformity in the adoption of supplemental codes by coastal counties and municipalities. It is the intent of this paper to present the structural design aspects required in a coastal building code using the code guidelines developed for and specifically applicable to Florida's coastal communities. These same design aspects and code guidance are applicable to most other state's or nation's developable sand shorelines which are subjected to coastal storm damage. The purpose of a coastal building code in Florida communities is to supplement the existing minimum code by providing the structural design standards for construction within that portion of the beach and dune system which is subject to substantial scour, erosion, flooding, and loads accompanying the impact of a major hurricane. A coastal building code includes structural design standards for the construction of residential structures, enclosed commercial structures, coastal and shore protection structures, and other substantial structures of a semi-permanent nature. Although the few minimum codes currently in effect in the coastal communities are comprehensive for conventional construction, they do not adequately address the special structural design considerations identified for the Florida coast. Along a developable coast, special design considerations are necessary for the preservation of the beach and dune systems, as well as, for the structural adequacy of the construction. The major concepts of coastal engineering design which are necessary in a coastal building code include: 1. Zone identification (horizontal and vertical). 2. Foundation design for erosion and scour. 3. Storm loading (including wind, waves, hydrostatic, and hydrodynamic loads).

In many design codes for roadway bridges, fatigue design involves passing a load model over an influence line for a critical location on the bridge and then determining the resulting nominal stress range. For fatigue design in the finite-life domain, this stress range is then multiplied by a damage equivalence factor to account for differences in the fatigue damage because of the load model and the expected real traffic. In general, the effects of simultaneous vehicle crossings are not considered in the calibration of the damage equivalence factor. In this paper, fatigue design procedures in the U.S., Canadian, European, and Swiss codes applicable for the design of steel or aluminum roadway bridges are first reviewed. A simulation-based study, conducted to investigate the effects of simultaneous vehicle crossings on the damage equivalence factors for North American roadway bridges, is then presented. Based on the results of this study, recommendations are made for amplifying the North American damage equivalence factors in cases where the effects of simultaneous vehicle crossings are expected to be significant.

The breakwater field in Holly Beach Louisiana was constructed in the early 1990’s by the Louisiana Department of Transportation and Development (LADOTD) in response to continued erosion of the shoreline and damage to Highway LA 82. Subsequent to the installation of the breakwater field, the beach continued to erode throughout the majority of the breakwater field. The continued erosion prompted the Louisiana Department of Natural Resources (LADNR) to undertake a sand management study (Coastal Planning & Engineering, Inc., 2000) to better understand the erosion and to protect the rod and environmentally sensitive marshes. The management plan recommendations included a beach nourishment project and structural rehabilitation of some of the breakwaters. These works were constructed in 2002-2003. This paper describes the improvements to the breakwater units. A related paper by Mann and Thomson, 2003, describes the beach nourishment design and implementation.

The key to implementing infrastructure asset management strategies is to have a comprehensive understanding of the asset performance, and how this performance changes over time. The rate of deterioration of pipes is affected by a number of factors. Although there are many condition assessment technologies and accelerated testing methods available, these techniques do not provide all of the required data on the factors effecting deterioration. Earlier efforts have been made to capture data on pipe failure and as described in the literature, these data have been used to develop of some prediction models. However, failure data alone are limited in terms of understanding pipeline deterioration. Forensic analyses of pipe samples extracted while in service as well as after failure are crucial in acquiring a comprehensive understanding of the rate of deterioration over time. Water sector utilities need feasible and sound protocols to analyze these pipe samples. This paper presents methods and protocols for failure and forensic analyses and collecting data on the deteriorated or failed pipe samples. These proposed protocols contain guidelines on capturing the environmental (soil, groundwater, climate, etc.), and structural (corrosion, fracture, fatigue, etc.) data for drinking water and wastewater pipelines with field and laboratory tests. Furthermore, a Web-based and GIS driven platform called PIPEiD (Pipeline Infrastructure Database) has been developed to collect and share the data produced following these failure and forensic analysis. The objectives of the PIPEiD is to unite the nation's water pipeline infrastructure data and information, to make it universally accessible and useful, and to provide access to the data sources, tools, and models that enable the analysis, simulation, visualization, and evaluation of the behavior of water pipeline infrastructure systems for advanced asset management. PIPEiD is envisioned to be “a Living Database Platform for Advanced Asset Management” addressing all three major asset management levels including strategic, tactical, and operational that will assist drinking water and wastewater utilities of all sizes to sustain targeted levels of service with acceptable risk.

The paper describes the main decisions leading to the construction of Gatun Dam, cited as the world's largest when completed. A brief summary of the dam's construction is subsequently presented as extracted from documents of the era. A description of the dam's post-construction performance is then given. Its uneventful history contrasts sharply with its controversial origins. Developments in engineering in the 20 th century have highlighted issues unknown to the designers and builders of the dam. These have motivated a detailed risk analysis of the structure, given that hydrologic and seismic demands now known are greater than previously believed. This evaluation process generated plans for remediation so that it can reliably carry out its function as the Panama Canal begins its second century of operation. The case also highlights, in a single structure, how much engineering practices have developed in this period.

This paper reports on model experiments and up to 20 years of practice in nature with a permeable groyne system, consisting of single or double permeable rows of wooden piles perpendicular to the beach, without bottom protection. This system costs only 10 to 25% of the impermeable stone groynes which have for centuries been used in the Netherlands. Model experiments confirm that wave-induced currents in the protected areas are reduced to 65%, and tidal currents even to 50%, depending on the pile screen configuration. Prototype measurements could not lead to straightforward conclusions with statistical significance: the effect of the pile screens on beach evolution is partly merged into natural fluctuations and trends. Wooden pile screens do not prevent the shoreward motion of tidal channels, which can cause washing out of piles. Furthermore, constructional failures, which in the future can be avoided, at some places resulted in negative experience. It is concluded that permeable pile screens deserve serious consideration as a first flexible and cheap phase in combating coastal erosion. Its application however should be based on a thorough analysis of the local coastal current climate.

During the last three decades several field and laboratory investigations have been conducted in which the waves generated by a wide variety of vessels have been measured. There is a need to synthesize the data published from these studies and to develop general ship wave prediction methods for designers. To complete this task some additional ship wave data must be collected. This paper initiates the effort to develop these prediction methods. A summary and critique of available data are given. Then, the appropriate portion of these data is employed to develop a ship wave height predictor model that gives the maximum ship wave height as a function of ship speed and displacement, water depth, and distance from the sailing line. This is an interim model that is quite applicable but can be improved pending additional data. Finally, planned future efforts to further develop design wave prediction methods are discussed.

By 2020, the U.S. public will enjoy benefits from an increase in gas use due to its affordable supply, reliable delivery, and environmental protection benefits. The Strategic Center for Natural Gas (SCNG) of the U.S. Department of Energy (DOE) oversees a wide range of research and development efforts that are producing innovative, affordable, safe, and environmentally-friendly natural gas technologies. SCNG is accomplishing its mission in partnership with the private sector, academia, and industry associations, to ensure that natural gas continues to be a viable component of a robust and diverse energy portfolio for America. The mission of SCNG is to be the focal point for an integrated gas program by spearheading annual DOE-wide gas research and development (R&D) planning and program assessment. This paper presents a summary of SCNG's current research projects.

An artificial beach nourishment used to replenish an eroding part of a coast may seem expensive and the need for repetition may discourage coastal managers. However, careful considerations of capital and maintenance cost frequently prove that it may be, in fact, the optimum solution. An added advantage is that the recreational function of the beach is preserved. In spite of a great number of research-reports and publications on coastal processes and beach nourishment, the practical applicability of this knowledge is still in an initial stage, i.e. formulating the general concepts and trying to test their validity and practical applicability. On the other hand, the solution of many practical coastal engineering problems cannot wait until complete understanding of these processes and the existing knowledge on this subject (though limited) should be made available for designers and managers involved in coastal engineering. This was the main reason for the Rijkswaterstaat (Dutch Public Works Department) to prepare a manual on artificial beach nourishment. In 1983, this Department established the task-group 'Profile Formation of Beaches', with the aim to study the relevant aspects of beach nourishment. These aspects concern among other things the influence of a beach fill on the coastal morphology and the environment, and the design and execution of a beach nourishment scheme. The members of the task-group originate from various governmental departments, research institutes (Delft Hydraulics) and private organisations (Volker Stevin Dredging, Zanen Verstoep Dredging Contractors). In addition to the members of the working-group some other persons and organizations (also outside the Netherlands) have contributed to the final report. The results of the studies have been described in a Manual on Beach Nourishment (Manual, 1986). This manual contains both theoretical and practical information, and is intended for persons and organisations who are involved in the prevention of beach erosion. Nearly all available and relevant literature to this subject has been incorporated. The actual paper reviews part of the contents of the Manual and summarizes aspects related to the aim, the different types and the design process of beach nourishment schemes.

A finite element model for combined refraction-diffraction problems of linear water waves has been extended to include the effect of various dissipative mechanisms on wave excitation response in harbours of arbitrary shape and variable depth. Especially, the effects of bottom friction, partial absorption along the harbour, contours, and transmission through permeable breakwaters have been considered. Although, within the mild slope approximation, the model is valid for arbitrary wave lengths, in this paper its effectiveness for harbour design applications is demonstrated for long wave induced resonance phenomena. For this purpose a realistic harbour geometry has been selected. A hydraulic scale-model of this harbour enabled experimental verification of the computational results.

On the basis of analyzing the factors that affect emergency logistics channel selection decision, this paper builds the evaluation index system for emergency logistics channel selection decision. This paper also builds a comprehensive evaluation method based on rough set theory and improved extension theory, by which we can get the emergency logistics channel selection decision sequence and the reliability level of all the alternative emergency logistics corridors. At last, the paper verifies the viability of the evaluation method through case study. This paper expands the application field of the extenics theory, changes the traditional method for emergency logistics channel selection decision, and provides new thoughts and methods for emergency logistics channel selection decision.

With the increase of people's travel demand, comprehensive passenger transport centers are increasingly significant in urban traffic systems. To provide better transfer service for passengers, based on transport modes adaptability theory of comprehensive passenger transport center, this paper introduced data envelopment analysis and synergetic theory. Furthermore, an evaluation model is established based on these two theories and transfer efficiency and synergy evaluation index systems are constructed. Taking Changchun City Railway Station passenger hub for example validation, this paper used the above evaluation model to calculate and analyze according to the survey data of train station in Changchun City. Finally, based on the final calculation results, this paper pointed out the problems of the existing transfer mode and provided a theoretical basis for the subsequent construction of the transfer center.

The present paper describes a study carried out to investigate floating breakwater behavior in waves. Components of the study include a field survey of floating breakwaters in British Columbia, Canada, the development of a numerical model of breakwater behavior and the experimental testing of a particular breakwater design. The numerical model has been developed to provide breakwater motions, transmission coefficients and mooring forces. The model combines linear diffraction theory for obliquely incident waves, a mooring analysis, the inclusion of viscous damping coefficients obtained from experimental or field data, and the inclusion of drag and wave drift forces for use in the static analysis of the moorings. The experiments were carried out with normally incident regular waves of different heights and periods. Preliminary results indicate that the numerical model should prove to be a useful tool in floating breakwater design.