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The repair of concrete port and harbor structures is one element of a larger problem in the United States and world wide. That is the general decay of infrastructure as a result of aging, design and construction deficiencies, and a scarcity of funds for maintenance. This report examines the concrete port and harbor structure portion of that crumbling infrastructure in an effort to understand the ways in which deterioration occurs and how it can be prevented, arrested or repaired. Concrete has many properties which makes it suitable and desirable for use in the marine environment. Quality concrete can be produced which has long-term strength gain, low permeability, self healing on cracking and self protection. Concrete can be cast in place or prefabricated and installed either onshore or offshore. In the following sections of this report, we characterize the marine environment for concrete port and harbor structures, review causes of deterioration, discuss methods for assessing deteriorated structures, and review repair methods currently in use.

The objective of this research was to develop reliability-based design methods for reinforced protective concrete structures. The analysis and design methods in the Air Force Protective Construction Design Manual (PCDM) provided the nominal (deterministic) methods that were used to perform probabilistic response analyses and the reliability assessments. One of the key objectives of this effort was to develop simplified rehability-based design methods, in the form of reliability-based design factors (RBDFs), that can be used by designers who are unfamiliar with probabilistic methods. Research was conducted in five fundamental areas: (1) airblast and aboveground structure response; (2) groundshock and belowground structure response; (3) fragmentation effects; (4) projectile penetration; (5) protective structure systems reliability. In each of the areas, emphasis was on reinforced concrete structures; however, the load uncertainty analyses are applicable to structures of any materials. In s instances we found significant biases in the PCDM models. In those cases where we found significant biases that could not be corrected without changes to the fundamental approach, RBDFs were not developed. Over twenty tables of RBDFs were developed for use with the PCDM procedures. Conventional Weapon Effects, Fragmentation, Airblast, Groundshock, Penetration, Reliability.

DSTA and NTU have been working together to develop a methodology to simulate the breakup and debris throw of reinforced concrete (RC) structures under internal explosion. The numerical simulation simulates the following five phases of the explosion event: internal loading; response and breakup; debris launch; debris trajectory and post ground impact. Results from the simulations of the various stages have been presented and discussed in previous DDESB seminars and other related conferences. This paper serves as an overview of the work done. In addition, the contribution of various parameters to the prediction of such dynamic response is assessed and tabulated.

In order to promote public education and public safety, equal justice for all, a better informed citizenry, the rule of law, world trade and world peace, this legal document is hereby made available on a noncommercial basis, as it is the right of all humans to know and speak the laws that govern them. (For more information: 12 Tables of Code ) Name of Legally Binding Document: BS NA EN 1992-2: UK National Annex to Eurocode 2. Design of concrete structures. Concrete bridges. Design and detailing rules Name of Standards Organization: British Standards Institution (BSI) LEGALLY BINDING DOCUMENT

The Corps of Engineers currently operates and maintains 536 dams and 260 lock chambers at 596 sites. Sixty percent of these hydraulic structures are over 20 years of age, more than 40 percent are more than 30 years old, and approximately one-third are more than 40 years old. With the relatively limited number of new construction starts anticipated, many of these structures are being and will continue to be kept in operation well beyond their original design lives. The primary objective of this study was to develop quantitative information on the present condition of the concrete portions of these structures. Two computerized data bases, (a) structure-description and (b) damage and repair, were compiled. The structure-description data base contains basic information (location, category, age, purpose, etc.) on 766 projects. The damage and repair data base contains information on the current condition of the concrete in the Corps' civil works structures as determined through detailed reviews of over 2000 periodic inspection reports. To assist in the analysis, a number of computer programs were developed to manipulate and search the data bases. This analysis concentrated on the types of deficiencies observed, the cause (if reported), location within the structure, and degree of damage. Also, if the deficiency had been repaired, the material or technique or both that were used and the performance were analyzed. This identification and assessment of problems relating to evaluation, maintenance, and repair of concrete will provide guidance in developing and establishing priorities for research in the Repair, Evaluation, Maintenance, and Rehabilitation (REMR) Research Program.

This document presents test problems which are intended to demonstrate the ability of SINGER to predict the response of plane frames and rings, including geometrically and physically nonlinear behavior, subject to static and dynamic actions. The following special features are illustrated: Inelastic behavior of a cantilever beam, discretization of an elastic ring under uniform pressure, large deformations of an elastic beam, and inelastic cyclic motion of a rod. The quality of the response predictions by SINGER is assessed on the basis of independent exact or approximate solutions.

This document presents test problems which are intended to demonstrate the ability of SINGER to predict the response of plane frames and rings, including geometrically and physically nonlinear behavior, subject to static and dynamic actions. The following special features are illustrated: Inelastic behavior of a cantilever beam, discretization of an elastic ring under uniform pressure, large deformations of an elastic beam, and inelastic cyclic motion of a rod. The quality of the response predictions by SINGER is assessed on the basis of independent exact or approximate solutions.

Failure criteria defining complete loss of section strength for reinforced concrete sections are defined in this Volume II of the report. Failure envelopes obtained from a three-dimensional finite element analysis with a three dimensional nonlinear constitutive material model are presented in terms of deformations for various rectangular and cylindrical sections. Applications and examples of the use of these failure envelopes are also presented. (Author)

Failure criteria defining complete loss of section strength for reinforced concrete sections are defined in this Volume II of the report. Failure envelopes obtained from a three-dimensional finite element analysis with a three dimensional nonlinear constitutive material model are presented in terms of deformations for various rectangular and cylindrical sections. Applications and examples of the use of these failure envelopes are also presented. (Author)

Source: Digital Library of India Scanning Centre: Allama Iqbal Library, University of Kashmir Source Library: Allama Iqbal Library, University Of Kashmir Date Accessioned: 8/6/2015 22:30 The Digital Library of India was a project under the auspices of the Government of India.

Proportioning of strength in an earthquake resistant structure is usually based on a linear elastic analysis and a set of equivalent static lateral forces. This design procedure has proven to be reliable on the basis of observed building damage caused by past earthquakes and has been adopted by present building codes. Presently, inelastic design of concrete structures subjected to load reversals is an art much like design of continuous structures subjected to gravity loadings was in the earlier part of the century. Inelastic stiffness characteristics of concrete components have been shown through experiments to be influenced by parameters not previously considered for analysis of structures subjected to montonically increasing forces. Hysteretic behavior of members and connections have been shown to be dependent on opening and closure of flexural and shear cracks, bond-slip mechanisms, softening of reinforcement, and inelasticity of concrete in compression. Because of the complexity of inelastic behavior and the uncertain sequence of ground excitations, several analyses need to be done so that an engineer may develop the judgement needed to implement a particular design. A simple tool needs to be developed for these analyses. The purpose of study described in this report is to develop an analytical technique that considers explicitly both the history of the ground motion, and the nonlinear hysteretic behavior of the structure. The technique is developed using nonlinear resistance characteristics of reinforced concrete structures, however, the basis of the method is applicable to any type of building structure.

Development of the resonant frequency technique as a method for evaluation of concrete structures is in progress. It is desirable that structures be evaluated in place, nondestructively, and in real time. The availability of digital Fourier analyzers and mathematical functions such as spectra, coherence, and transfer relationships permits the analysis of the behavior of large structures under dynamic conditions in place and in real time. An impact system has been tested which was proven more economical and versatile than the sinusoidal system currently in use. With transient loading, all frequencies are applied to the structure simultaneously rather than being swept through one at a time. Because the resonant frequency of a structure is directly related to its dynamic Young's modulus and hence its mechanical integrity, the resonant frequency technique is useful in the field as well as in the laboratory. Factors that influence the soundness and safety of a structure, such as modulus, continuity, and boundary conditions (i.e. foundation and other restraints) also directly affect the resonant frequency. Some limited work has been done with both mathematical and physical modeling to develop measurement criteria that will improve prediction of the expected resonant frequency for structures with varying geometries and varying degrees of foundation restraint. The characteristic vibrational signature of a structure may be evaluated at selected time intervals in an effort to predict service life. Improvement in modal analysis and prediction of frequencies by mathematical modeling is needed. Field work has demonstrated the feasibility of the technique. (Author)

This manual describes the development and use of response spectra for the seismic analysis of concrete hydraulic structures. The manual provides guidance regarding how earthquake ground motions are characterized as design response spectra and how they are then used in the process of seismic structural analysis and design. The manual is intended to be an introduction to the seismic analysis of concrete hydraulic structures. More detailed seismic guidance on specific types of hydraulic structures will be covered in engineer manuals and technical letters on those structures.

Lectures from the National Programme on Technology Enhanced Learning - Civil Engineering - Prestressed Concrete Structures

Lectures from the National Programme on Technology Enhanced Learning - Civil Engineering - Prestressed Concrete Structures

Lectures from the National Programme on Technology Enhanced Learning - Civil Engineering - Prestressed Concrete Structures

Source: Digital Library of India Scanning Centre: C-DAC, Noida Source Library: Delhi College Of Engineering Date Accessioned: 6/24/2015 3:10 The Digital Library of India was a project under the auspices of the Government of India.

In older buildings, such as those common on U.S. Army installations, severe damp-basement problems can increase maintenance requirements and make affected areas uninhabitable or even unusable. In problem areas, the usual approach to solve groundwater intrusion problems is to excavate to expose the wall area and the base of the foundation (trench) and then to replace damp proofing on the wall surface and to install a drain tile system around the building or affected area (drain). A commercial system that uses electro-osmotic pulse (EOP) technology within concrete structures offers an alternative to the trench-and-drain approach that can mitigate water-related problems from the interior (negative side) of affected areas without the cost of excavation. EOP technology is designed to extend the life of conventional repair methods. In basic terms, the EOP system uses pulses of electricity to reverse the flow of water seepage, actually causing moisture to flow out of the basement walls, away from the building. This study demonstrated and validated EOP technology by performing laboratory and field tests of a commercially available EOP system at selected Army installations, and by comparing the results of those test with the results of conventional dampness mitigation techniques.

In older buildings, such as those common on U.S. Army installations, severe damp-basement problems can increase maintenance requirements and make affected areas uninhabitable or even unusable. In problem areas, the usual approach to solve groundwater intrusion problems is to excavate to expose the wall area and the base of the foundation (trench) and then to replace damp proofing on the wall surface and to install a drain tile system around the building or affected area (drain). A commercial system that uses electro-osmotic pulse (EOP) technology within concrete structures offers an alternative to the trench-and-drain approach that can mitigate water-related problems from the interior (negative side) of affected areas without the cost of excavation. EOP technology is designed to extend the life of conventional repair methods. In basic terms, the EOP system uses pulses of electricity to reverse the flow of water seepage, actually causing moisture to flow out of the basement walls, away from the building. This study demonstrated and validated EOP technology by performing laboratory and field tests of a commercially available EOP system at selected Army installations, and by comparing the results of those test with the results of conventional dampness mitigation techniques.

This report presents design aids for use in the design and analysis of reinforced concrete hydraulic structural members subjected to combined uniaxial bending and axial loads. A total of 190 load-moment strength interaction diagrams for both single and double reinforced members with various compressive strengths of concrete, yield strengths of steel reinforcement, reinforcement ratios, and concrete covers is included. In addition to design aids, this report includes a commentary explaining how each design aid was calculated, and design examples illustrating the use of the design aids. (Author)

This report presents design aids for use in the design and analysis of reinforced concrete hydraulic structural members subjected to combined uniaxial bending and axial loads. A total of 190 load-moment strength interaction diagrams for both single and double reinforced members with various compressive strengths of concrete, yield strengths of steel reinforcement, reinforcement ratios, and concrete covers is included. In addition to design aids, this report includes a commentary explaining how each design aid was calculated, and design examples illustrating the use of the design aids. (Author)

This item represents a case in PACER, the U.S. Government's website for federal case data. This information is uploaded quarterly. To see our most recent version please use the source url parameter, linked below. To see the canonical source for this data, please consult PACER directly.

The monumental treatise "\'El\'ements de math\'ematique" of N. Bourbaki is based on the notion of structure and on the theory of sets. On the other hand, the theory of categories is based on the notions of morphism and functor. An appropriate definition of a structure in a concrete category is given in this paper. This definition makes it possible to bridge the gap between Bourbaki's structural approach and the categorical language.

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An electrical impedance spectroscopy-based nondestructive testing (NDT) method is proposed to image both cracks and reinforcing bars in concrete structures. The method utilizes the frequency-dependent behavior of thin insulating cracks: low-frequency electrical currents are blocked by insulating cracks, whereas high-frequency currents can pass through the conducting bars without being blocked by thin cracks. Rigorous mathematical analysis relates the geometric structures of the cracks and bars to the frequency-dependent Neumann-to-Dirichlet data. Various numerical simulations support the feasibility of the proposed method.

An electrical impedance spectroscopy-based nondestructive testing (NDT) method is proposed to image both cracks and reinforcing bars in concrete structures. The method utilizes the frequency-dependent behavior of thin insulating cracks: low-frequency electrical currents are blocked by insulating cracks, whereas high-frequency currents can pass through the conducting bars without being blocked by thin cracks. Rigorous mathematical analysis relates the geometric structures of the cracks and bars to the frequency-dependent Neumann-to-Dirichlet data. Various numerical simulations support the feasibility of the proposed method.

An electrical impedance spectroscopy-based nondestructive testing (NDT) method is proposed to image both cracks and reinforcing bars in concrete structures. The method utilizes the frequency-dependent behavior of thin insulating cracks: low-frequency electrical currents are blocked by insulating cracks, whereas high-frequency currents can pass through the conducting bars without being blocked by thin cracks. Rigorous mathematical analysis relates the geometric structures of the cracks and bars to the frequency-dependent Neumann-to-Dirichlet data. Various numerical simulations support the feasibility of the proposed method.

An electrical impedance spectroscopy-based nondestructive testing (NDT) method is proposed to image both cracks and reinforcing bars in concrete structures. The method utilizes the frequency-dependent behavior of thin insulating cracks: low-frequency electrical currents are blocked by insulating cracks, whereas high-frequency currents can pass through the conducting bars without being blocked by thin cracks. Rigorous mathematical analysis relates the geometric structures of the cracks and bars to the frequency-dependent Neumann-to-Dirichlet data. Various numerical simulations support the feasibility of the proposed method.

An electrical impedance spectroscopy-based nondestructive testing (NDT) method is proposed to image both cracks and reinforcing bars in concrete structures. The method utilizes the frequency-dependent behavior of thin insulating cracks: low-frequency electrical currents are blocked by insulating cracks, whereas high-frequency currents can pass through the conducting bars without being blocked by thin cracks. Rigorous mathematical analysis relates the geometric structures of the cracks and bars to the frequency-dependent Neumann-to-Dirichlet data. Various numerical simulations support the feasibility of the proposed method.

Book digitized by Google from the library of the University of Wisconsin - Madison and uploaded to the Internet Archive by user tpb.

Book digitized by Google from the library of the University of Wisconsin - Madison and uploaded to the Internet Archive by user tpb.

Book digitized by Google from the library of the University of Wisconsin - Madison and uploaded to the Internet Archive by user tpb.

Book digitized by Google from the library of the University of Wisconsin - Madison and uploaded to the Internet Archive by user tpb.

Book digitized by Google from the library of the University of Wisconsin - Madison and uploaded to the Internet Archive by user tpb.

This item represents a case in PACER, the U.S. Government's website for federal case data. If you wish to see the entire case, please consult PACER directly.

This item represents a case in PACER, the U.S. Government's website for federal case data. If you wish to see the entire case, please consult PACER directly.

This item represents a case in PACER, the U.S. Government's website for federal case data. If you wish to see the entire case, please consult PACER directly.

This item represents a case in PACER, the U.S. Government's website for federal case data. If you wish to see the entire case, please consult PACER directly.

This item represents a case in PACER, the U.S. Government's website for federal case data. If you wish to see the entire case, please consult PACER directly.

This item represents a case in PACER, the U.S. Government's website for federal case data. If you wish to see the entire case, please consult PACER directly.

The investigation documents the experience gained by the Corps of Engineers and the Navy since World War II in the use of coral as an aggregate for portland cement concrete. The approach was to evaluate relevant literature and construction and inspection records, visit construction and material preparation sites, evaluate existing coral concrete structures, and analyze coral aggregate and coral concrete samples in the laboratory. The results of the investigation indicate that coral has successfully been used as an aggregate for concrete in vertical construction. The only significant type of deterioration observed in coral concrete structures was the cracking and spalling of concrete associated with corroding reinforcing steel. The severity of the corrosion- spalling problem was sufficient in some cases to affect structural integrity, while in other cases little or no deterioration was observed. For the most part specifications and construction techniques currently being used for production of coral aggregate and coral concrete are similar to specifications and techniques for conventional aggregate and concrete.

This document is a user's guide to the SINGER computer program. The guide defines the form and interpretation of input and output data. SINGER predicts the transient response of two dimensional reinforced concrete frames subjected to time varying loadings, accounting for nonlinear material effects and large geometry changes.

This document is a user's guide to the SINGER computer program. The guide defines the form and interpretation of input and output data. SINGER predicts the transient response of two dimensional reinforced concrete frames subjected to time varying loadings, accounting for nonlinear material effects and large geometry changes.

This item represents a case in PACER, the U.S. Government's website for federal case data. This information is uploaded quarterly. To see our most recent version please use the source url parameter, linked below. To see the canonical source for this data, please consult PACER directly.

Study of the effect of confinement of concrete on the seismic performance and behavior of permanent shuttering concrete panel structures is the subject of this paper. For this purpose, a few building models with different heights, but similar planar layout of walls, with and without considering the effect of confinement, i.e. execution of boundary elements, are taken into consideration. For this study, the PERFORM 3D software is employed for the modeling of nonlinear behavior of these structures by the possibility of using a multi layer shell element with fiber sections. For finite element modeling of these sections two types of concrete fibers, confined and non-confined, are employed. After modeling and carrying out nonlinear analyses, performance of each of specimens at two different risk levels is determined. The obtained results indicate that although execution of the boundary elements in these structural systems does not considerably improve the seismic performance but the confinement is a major factor in improving some parameters such as ductility, the probable maximum strength and the loss of energy that have a positive influence on the seismic performance of the structure.

Includes bibliographical references and index

Includes bibliographical references and index

In order to promote public education and public safety, equal justice for all, a better informed citizenry, the rule of law, world trade and world peace, this legal document is hereby made available on a noncommercial basis, as it is the right of all humans to know and speak the laws that govern them. (For more information: 12 Tables of Code ) Name of Standards Organization: Bureau of Indian Standards (BIS) Division Name: Civil Engineering Section Name: Construction Management including safety in Construction (CED 29) Designator of Legally Binding Document: IS 8989 Title of Legally Binding Document: Safety code for erection of concrete framed structures Number of Amendments: Equivalence: Superceding: Superceded by: LEGALLY BINDING DOCUMENT Step Out From the Old to the New --Jawaharlal Nehru Invent a new India using knowledge. --Satyanarayan Gangaram Pitroda

In order to promote public education and public safety, equal justice for all, a better informed citizenry, the rule of law, world trade and world peace, this legal document is hereby made available on a noncommercial basis, as it is the right of all humans to know and speak the laws that govern them. (For more information: 12 Tables of Code ) Name of Standards Organization: Bureau of Indian Standards (BIS) Committee Designation: WRD 23 Designator of Legally Binding Document: IS 9401 : Part 4 : 2018 Title of Legally Binding Document: Method of Measurement of Works in River Valley Projects (Dams and Appurtenant Structures) Part 4 Concrete Works ( First Revision ) Number of Amendments: 0 Status: Active Additional Info: (Reaffirmed Year : 2022 ) LEGALLY BINDING DOCUMENT Step Out From the Old to the New --Jawaharlal Nehru