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Water and wastewater conveyance research is steeply based in advancements of numerical methods and models. Design engineers need more than refinements in analysis methods to evolve the standards of practice and the related design guidelines. In an effort to improve the design efficiency and operating reliability of pipeline systems, design guidelines have been developed to enfold the various technological advancements and elevate the standard of care used in the pipeline design process. In this respect, the guidelines have been successful. However, design engineers, manufacturers, and owners have developed a level of dependency on the success of the guidelines. The guidelines, which were developed as and are clearly still held to be by the various publishing associations, a minimum standard of care, have become the default standard of care. Such statements are, of course, gross generalizations, but this thesis is dedicated to move the standard of care forward through an integrated design approach that provides a roadmap to inter-relate the independent design guidelines into a composite design approach based on hydrodynamic loading. Hydrodynamic loading introduces of a temporal parameter into the design process. With the temporal parameter this work demonstrates how the consideration of both the frequency and the influence of acceleration head on the magnitude of the hydraulic loading can be used to integrate and evolve the individual component designs into a more efficient, cost effective, reliable composite design result. With a temporal parameter present in design, many opportunities present themselves to advance the current design procedures outlined in the present design guidelines. This thesis identifies some of the present shortcomings found in the modern pipeline and appurtenance design standards and introduces a recommended path forward. Specific changes to the present standards are proposed in this work and a unique analysis procedure to identify the failure potential of cement mortar lining has been developed. Introducing the integrated design approach will allow for a significant evolution to the present standard of practice in water and wastewater conveyance system designs.

Water and wastewater conveyance research is steeply based in advancements of numerical methods and models. Design engineers need more than refinements in analysis methods to evolve the standards of practice and the related design guidelines. In an effort to improve the design efficiency and operating reliability of pipeline systems, design guidelines have been developed to enfold the various technological advancements and elevate the standard of care used in the pipeline design process. In this respect, the guidelines have been successful. However, design engineers, manufacturers, and owners have developed a level of dependency on the success of the guidelines. The guidelines, which were developed as and are clearly still held to be by the various publishing associations, a minimum standard of care, have become the default standard of care. Such statements are, of course, gross generalizations, but this thesis is dedicated to move the standard of care forward through an integrated design approach that provides a roadmap to inter-relate the independent design guidelines into a composite design approach based on hydrodynamic loading. Hydrodynamic loading introduces of a temporal parameter into the design process. With the temporal parameter this work demonstrates how the consideration of both the frequency and the influence of acceleration head on the magnitude of the hydraulic loading can be used to integrate and evolve the individual component designs into a more efficient, cost effective, reliable composite design result. With a temporal parameter present in design, many opportunities present themselves to advance the current design procedures outlined in the present design guidelines. This thesis identifies some of the present shortcomings found in the modern pipeline and appurtenance design standards and introduces a recommended path forward. Specific changes to the present standards are proposed in this work and a unique analysis procedure to identify the failure potential of cement mortar lining has been developed. Introducing the integrated design approach will allow for a significant evolution to the present standard of practice in water and wastewater conveyance system designs.

Thesis (M.App.Sc.) - Carleton University, 2007. / Includes bibliographical references (p. 128-137). Also available in electronic format on the Internet.

This thesis investigates and discusses the current design approaches and development trends of urban streets in China. As the methodological focus, multiple case studies and interviews are used to examine actual street design practice to identify the development policy bias of local governments. Since the 1990s, the great economic achievement in most Chinese cities has evoked significant growth in the number of automobiles, as well as the increasingly serious problems of road casualties and congestion. The traffic-engineering-based design approach which used to be widely adopted and implemented in western countries has dominated the development patterns of urban streets in modern China. The conventional paradigm exclusively focuses on the traffic function in urban streets resulting in morphological changes to the urban circulation environment and keeps on neglecting non-vehicular movement and non-traffic needs. The automobile- dominated urban circulation environment has had negative economic, social and public health impacts. Thus, a paradigm shift which calls for a more inclusive design approach for urban streets which balances functions of place and movement is urgently needed in China. To determine the challenges and opportunities for the new paradigm, this research identifies the cultural, political and technical factors for the traffic-centred design trends and the policy bias. Based on this, policy recommendations and an agenda for revolutionary change for achieving better design practice for urban streets in post-modern China are suggested.

Thesis (PhD)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Structural design standards based on the principles of structural reliability are gaining worldwide acceptance and are fast becoming the new basis for structural safety verification. The application of these principles to establish a standardised basis for structural design using partial factor limit states design procedures is done in the European Standard for the Basis of Structural Design EN 1990 from which it is adapted to the South African Standard Basis of Design for Building and Industrial Structures SANS 10160-1. South Africa (SA) is on the advent of adopting the European Concrete Design Standard EN 1992-1-1 (EC2) as the equivalent standard for local use. This investigation seeks to provide a transparent quantitative reliability basis for the SA’s adoption of EC2, as well as provide for its subsequent implementation under local conditions and practice. The investigation kicks-off with a critical review of the reliability framework for structural resistance. The review establishes the relationships between the key elements of the framework, shedding light on issues SA needs to consider as it adopts EC2. Important issues for SA to consider include (1) target levels of structural performance ( -values), (2) partial factors, (3) model uncertainties, and (4) quality control. Design for shear resistance was investigated in greater detail by comparison of EC2’s Variable Strut Inclination Method (VSIM) for stirrup design against alternative approaches, namely, (1) South Africa’s currently operational SANS 10100-1 procedure, and (2) the fib Model Code 2010 first Level of Approximation (LoA I) and fib LoA III, which are based on the Modified Compression Field Theory (MCFT). Unbiased capacity predictions from the MCFT-based sectional analysis Program Response-2000 (R2k) served as LoA IV best-estimate results during this assessment. Results of this investigation showed that EC2 offers higher capacity predictions in excess of 1 MPa of stirrup reinforcement, with significantly higher predictions in the range of 1 to 2 MPa. A reliability performance assessment was therefore commissioned to assess safety regimes in terms of achieved reliability across a parametric range of the amount of stirrup reinforcement (from 0.45 to 2.0 MPa). The First Order Reliability Method (FORM) was implemented as part of the reliability performance assessment of the EC2’s VSIM design procedure. The model uncertainty for shear resistance (stirrup failures) was characterised according to a database of published stirrupreinforced concrete beam shear tests. Three cases of the Model Factor for shear resistance were derived from the experimental database for alternative shear resistance prediction models; two of which formed part of basic investigations conducted using the conventionally formulated performance function, and the other was integrated as part of an independent validation procedure using R2k predictions to obtain the reliability model. Results obtained from the basic reliability model ( -values) generally indicated lower levels of reliability with an increase in stirrup reinforcement and concrete strength, compared to those estimated from the R2k-based reliability model ( -values). The disparity between and -values revealed that systematic effects affect each model’s ability to predict the expected value of true shear resistance . There is reasonable evidence to suggest that the predictions of can be improved by accounting for each model’s peculiar sensitivity to concrete strength, consequently providing more representative estimates of . However, in the interim, and -values, respectively, represent reasonable lower and upper bound estimates of the performance of EC2’s VSIM design procedure. / AFRIKAANSE OPSOMMING: Die beginsels van struktuur betroubaarheid word wêreldwyd aanvaar as basis vir struktuur ontwerp standaarde en die versekering van voldoende struktuur veiligheid. Hierdie beginsels word in die Europese Standaard Basis of Structural Design EN 1990 toegepas om gestandaardiseerde partiële faktor gebaseerde limietstaat ontwerp prosedures daar te stel, van waar dit aangepas is vir die Suid-Afrikaanse Standaard Basis of Design for Building and Industrial Structures SANS 10160-1. Suid-Afrika (SA) staan op die punt om die Europese beton ontwerp standaard EN 1992-1-1 (EC2) aan te neem as die ekwivalente standaard vir plaaslike gebruik. Hierdie ondersoek het as doel om ‘n deursigtige kwantitatiewe betroubaarheidsbasis daar te stel vir die aanneming van EC2 as SA standaard en om voorsiening te maak vir die implementering daarvan onder plaaslike toestande en –praktyk. Die ondersoek begin met ‘n kritiese oorsig van die betroubaarheidsraamwerk vir strukturele weerstand. Die oorsig stel die verhouding vas tussen sleutel elemente van die raamwerk en werp lig op aspekte wat SA moet oorweeg in die aanneming van EC2. Belangrike aspekte vir oorweging sluit (1) teiken betroubaarheidsvlakke vir struktuur gedrag ( -waardes), (2) partiele faktore, (3) model onsekerhede en (4) kwaliteitsbeheer in. Skuif weerstandsontwerp is in groter detail ondersoek deur die EC2 se Veranderbare Stut Hoek Metode (VSHM) vir skuifbeuel ontwerp te vergelyk met alternatiewe benaderings, naamlik, (1) Suid Afrika se huidig operasionele SANS 10100-1 prosedure, (2) fib Model Code 2010 se sogenaamde eerste Vlak van Benadering (VvB I) en fib VvB III, gebaseer op die Aangepaste Drukveld Teorie (ADT). Onbevooroordeelde kapasiteit voorspellings van die ADT-gebaseerde snit analise program “Response-2000 (R2k)” is in die evaluering gebruik as VvB IV bes benaderde resultate. Die ondersoek toon dat EC2 hoër kapasiteit voorspel vir skuifbeuel bewapening tot 1 MPa en beduidend hoër kapasiteite voorspel vir skuifbeuel bewapening tussen 1 en 2 MPa. ‘n Betroubaarheidsprestasie studie is vervolgens geloots om die veiligheid in terme van behaalde betroubaarheid te bepaal oor ‘n parametriese bereik van 0.45 tot 2.0 MPa skuifbeuel bewapening. Die Eerste Orde Betroubaarheids Metode (EOBM) is implementeer as deel van die betroubaarheidsprestasie beoordeling van die EC2 VSHM ontwerp prosedure. ‘n Databasis van gepubliseerde skuifbeuel-bewapende betonbalk skuiftoetse is gebruik om die model onsekerheid vir die verskillende skuifweerstandsmodelle statisties te beskryf. Drie Model Faktore is uit die eksperimentele databasis afgelei, twee waarvan gebruik is in basiese ondersoeke met die konvensioneel geformuleerde prestasie funksie en die derde as deel van ‘n onafhanklike bevestigingsprosedure gebaseer op R2k voorspellings. Resultate wat verkry is uit die basiese betroubaarheidsmodel ( -waardes) was laer (meer konserwatief), en het ook vinniger afgeneem met ‘n toename in skuifbeuel bewapening as die waardes wat uit die R2k-gebaseerde betroubaarheidsmodel ( -waardes) verkry is. Die verskil tussen β en β -waardes toon dat sistematiese effekte die vermoë van elk van die modelle beïnvloed om die verwagte waarde van die werklike skuifweerstand V te voorspel. Daar is redelike bewyse om aan te voer dat die voorspellings van V verbeter sal kan word deur elke model se unieke sensitiwiteit teenoor betonsterkte in ag te neem, om sodoende meer verteenwoordigende β waardes te verkry. Intussen verteenwoodig die β en β -waardes onderskeidelik redelike onder- en bogrens skattings vir die prestasie van EC2 se VSHM ontwerp prosedure.

<p>After only two years of service, extensive cracking was found in the webs of two light-rail commuter line bridges in Stockholm, the Gröndal and Alvik bridges. Due to this incident it was found necessary to study the means available for analysing shear cracking in concrete structures subjected to in-plane stresses. The aim of this PhD project is to study shear cracking with these two bridges as reference. In this thesis, the first part aims to study the possibility of using finite element analysis as a tool for predicting shear cracking for plane state stresses. The second part is concerning how the shear cracks are treated in the concrete design standards.</p><p>Shear cracking in reinforced beams has been studied with non-linear finite element analyses. In these analyses the shear cracking behaviour was compared to experiments conducted to analyse the shear failure behaviour. Finite element analyses were performed with two different FE programs Abaqus and Atena. The material model used in Atena is a smeared crack model based on damage and fracture theory with either fixed or rotated crack direction. The material model used in Abaqus is based on plasticity and damage theory. The fixed crack model in Atena and the model in Abaqus gave good results for all studied beams. For the two studied deep beams with flanges the results from the rotated crack model were almost the same as obtained with the fixed crack model. The rotated crack model in Atena gave though for some beams a rather poor estimation of the behaviour.</p><p>The calculation of crack widths of shear cracks has been studied for the long-term load case in the serviceability state for the Gröndal and Alvik bridges, with the means available in the design standards. The methods based on the crack direction corresponding to the principal stress and do not include the effect of aggregate interlocking seems to be too conservative. Two of the studied methods included the effect of aggregate interlocking, it was made either by introducing stresses in the crack plane or implicitly by changing the direction of the crack so that it no longer coincide with the direction of principal stress. For calculations based on probable load conditions, these methods gave estimations of the crack widths that were close to the ones observed at the bridges. Continuous measurements of cracks at the Gröndal and the Alvik bridges have also been included. Monitoring revealed that the strengthening work with post-tensioned tendons has, so far, been successful. It also revealed that the crack width variations after strengthening are mainly temperature dependent where the daily temperature variation creates movements ten times greater than those from a passing light-rail vehicle. Monitoring a crack between the top flange and the webs on the Gröndal Bridge showed that the top flange was moving in a longitudinal direction relative to the web until the strengthening was completed. The crack widths in the sections strengthened solely by carbon fibre laminates seem to increase due to long-term effects.</p>

After only two years of service, extensive cracking was found in the webs of two light-rail commuter line bridges in Stockholm, the Gröndal and Alvik bridges. Due to this incident it was found necessary to study the means available for analysing shear cracking in concrete structures subjected to in-plane stresses. The aim of this PhD project is to study shear cracking with these two bridges as reference. In this thesis, the first part aims to study the possibility of using finite element analysis as a tool for predicting shear cracking for plane state stresses. The second part is concerning how the shear cracks are treated in the concrete design standards. Shear cracking in reinforced beams has been studied with non-linear finite element analyses. In these analyses the shear cracking behaviour was compared to experiments conducted to analyse the shear failure behaviour. Finite element analyses were performed with two different FE programs Abaqus and Atena. The material model used in Atena is a smeared crack model based on damage and fracture theory with either fixed or rotated crack direction. The material model used in Abaqus is based on plasticity and damage theory. The fixed crack model in Atena and the model in Abaqus gave good results for all studied beams. For the two studied deep beams with flanges the results from the rotated crack model were almost the same as obtained with the fixed crack model. The rotated crack model in Atena gave though for some beams a rather poor estimation of the behaviour. The calculation of crack widths of shear cracks has been studied for the long-term load case in the serviceability state for the Gröndal and Alvik bridges, with the means available in the design standards. The methods based on the crack direction corresponding to the principal stress and do not include the effect of aggregate interlocking seems to be too conservative. Two of the studied methods included the effect of aggregate interlocking, it was made either by introducing stresses in the crack plane or implicitly by changing the direction of the crack so that it no longer coincide with the direction of principal stress. For calculations based on probable load conditions, these methods gave estimations of the crack widths that were close to the ones observed at the bridges. Continuous measurements of cracks at the Gröndal and the Alvik bridges have also been included. Monitoring revealed that the strengthening work with post-tensioned tendons has, so far, been successful. It also revealed that the crack width variations after strengthening are mainly temperature dependent where the daily temperature variation creates movements ten times greater than those from a passing light-rail vehicle. Monitoring a crack between the top flange and the webs on the Gröndal Bridge showed that the top flange was moving in a longitudinal direction relative to the web until the strengthening was completed. The crack widths in the sections strengthened solely by carbon fibre laminates seem to increase due to long-term effects. / QC 20101119

Строительные нормы и правила устанавливают основные требования к проектированию жилых зданий и отражают национальные законы и административные правила проектирования жилых зданий. Выполнен анализ нормативных документов строительной отрасли в Китае и Российской Федерации. Целью данного исследования является проведение сравнительного анализа и выявление сходств и различий между кодексами жилищного строительства регионов России и Китая. Результаты анализа кодексов жилищного строительства могут послужить теоретической основой для дальнейших исследований в области жилищного строительства в обеих странах. / Building codes establish the basic requirements for the design of residential buildings and reflect national laws and administrative regulations for the design of residential buildings. An analysis of regulatory documents of the construction industry in China and the Russian Federation was carried out. The purpose of this study is to conduct a comparative analysis and identify similarities and differences between the housing construction codes of the regions of Russia and China. The results of the analysis of housing codes can serve as a theoretical basis for further research in the field of housing construction in both countries.