Reports (Civil Engineering)
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This research project was funded through an agreement signed in January, 1975 by the Brazilian Government and the United Nations Development programme (UNDP). The Ministry of Transportation, acting through the Brazilian Transportation Planning Agency (GEIPOT), assumed responsibility for the project on behalf of the Brazilian Government and the International Bank for Reconstruction and Development (IBRD) acted as the executing agency for UNDP.
The research was carried out by GEIPOT and the National Highway Department (DNER), acting through its Road Research Institute (IPR). Funding from the Brazilian Government was channeled through the Institute for Economic and Social Planning (IPEA) and the Secretariat for International Economic and Technical Cooperation (SUBIN), along with the Ministry of Transportation. from Preface, ICR Research Final Report- 1981
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Item Final report : Study into the causes of the Jagersfontein Fine Tailings Storage Dam failure on 11 September 2022University of Pretoria; University of the Witwatersrand; Department of Civil Engineering; Jacobsz, Schalk Willem; Torres-Cruz, Luis (Republic of South Africa. Department of Water and Sanitation, 2024-09-06)This report presents an investigation into the geotechnical causes of the Jagersfontein Fine Tailings Storage Dam failure which occurred at approximately 06h00 on the morning of Sunday 11 September 2022. The dam is registered with the Department of Water and Sanitation as the “Jagersfontein Fine Tailings Storage Facility Dam”, a Category III dam with a safety risk. It is owned by Jagersfontein Developments (Pty) Ltd who focuses on reprocessing legacy tailings dumps from previous mining operations. The De Beers mining company operated the Jagersfontein mine until it ceased operations in 1971. The mine and associated tailings dam remained dormant until 2010 when reprocessing of legacy tailings dumps, without any further underground activities, commenced. Jagersfontein Developments (Pty) Ltd developed two new tailings deposition compartments adjacent to an old tailings dam built by the De Beers Group during their tenure of the Jagersfontein Mine. Construction of the first compartment began in 2010 immediately to the west of the old dam. Construction of the second compartment began in 2015, located to the south and east of the old dam. The new eastern compartment merged with the old tailings dam between 2017 and 2018. At that point the tailings facility consisted of two main areas, a western and eastern compartment. These two compartments merged between 2020 and 2021 to create a facility that consisted of a single deposition area. It was the southern wall of the eastern compartment, of which construction began in 2015, that failed on 11 September 2022. The Investigation Panel comprised geotechnical engineers from the Universities of Pretoria and the Witwatersrand appointed by the Directorate: Dam Safety Regulation of the Department of Water and Sanitation. A second and parallel study, documented in a separate report, involved a dam breach study by hydraulic engineers of the University of Pretoria. The geotechnical study included three site visits: The first involved a site walkover and collection of a limited number of samples. During the second site visit a piezocone (CPTu) investigation was carried out as well as sample collection. The third visit comprised a seismic CPTu investigation, Mostap sampling and further collection of samples for index testing. Due to legal reasons the Investigation Panel was not permitted to discuss the tailings dam failure with personnel of Jagersfontein Developments (Pty) Ltd. The investigation included a desk study of documentation provided to the Investigation Panel via the Department of Water and Sanitation, as well as a study of aerial and satellite images, some freely available and some purchased. Available data also included several surveys of the dam carried out from time to time. The design report (Robinson, 2015) for the eastern compartment of which the southern wall failed indicated that the compartment was constructed on land already impacted by legacy fine tailings deposits. This was supported by aerial and satellite images. The design report indicated that the fine tailings had a low shear strength, recommending a 20° effective friction angle and a very low permeability of 1 x 10-12 m/s. In brief, the design for the eastern compartment comprised outer walls constructed from coarse tailings (grits), to contain the fine tailings slurry (slimes) deposited hydraulically in the tailings dam. The outer walls were raised via upstream construction. The satellite images showed signs of instability along the eastern third of the southern wall of the tailings dam starting in Feb 2019. This eastern third of the tailings dam wall was adjacent to a water storage dam known as Dam 10. The first signs of instability were seen just after Dam 10 filled up rapidly from rainfall after being empty during the dry first half of the 2018 - 2019 summer. Based on available information, the slope showing signs of instability was constructed at what is believed to be the natural angle of repose of the coarse tailings (grits) (1:1.5 or approximately 33°). This is steeper than the recommended design angle available to the Investigation Panel (1:2 or approximately 27°). It appears that this section of the wall is underlain at least partially by an old tailings dump, referred to as Dump 10, which the Investigation Panel believes represents a foundation of inadequate shear strength. Satellite imagery showed a large amount of southward movement taking place along the toe of the affected section of the dam wall from February 2019 until the failure in September 2022. Changes in the alignment of the access road directly downstream of the southern wall of the dam show how an initially straight road became curved around the affected part of the wall, eventually deviating 87 m from its original alignment. Satellite images showed substantial increased construction activity along the affected section of the wall, which is interpreted to have been efforts to maintain stability while the dam was kept in use. The affected section of the wall had a footprint width of approximately twice the footprint width of any other part of the dam wall at the time of the failure. Stability analyses show that the section of the wall that first showed signs of distress was unstable when assuming drained strength parameters. The first slope instability was likely triggered by the rapid filling of Dam 10. Thereafter, near continuous movement seems to have occurred, which the Investigation Panel believe would have resulted in undrained conditions along an interface between the dam wall and its foundation. Such undrained conditions would have reduced the strength to levels insufficient to ensure stability. Satellite images indicate a reduction in the rate of movement at the toe in the months preceding the failure, but some acceleration in the rate of inward widening of the embankment crest along parts of the southern wall during this time. As the dam did not have a decant facility, no beach could form and water and/or fine tailings slurry often extended right up against the inner slopes of the crest. Upstream raising of the dam therefore had to be constructed on poorly consolidated tailings. An eyewitness account indicates that, on the morning of the failure, part of the crest failed to the inside. This was followed by slumping of the crest, overtopping and the uncontrolled release of approximately 5.1 million m3 of tailings slurry and water. The Investigation Panel believes that the failure at the inside of the crest provided a trigger to remobilise undrained conditions at the base of the dam wall, reducing the shear strength along the zones where movement had been occurring for a long time, resulting in the failure of the Jagersfontein Fine Tailings Storage Dam.Item Final report. Volume 5, Research on the Interrelationships Between Costs of Highway Construction, Maintenance and UtilizationEmpresa Brasileira de Planejamento de Transportes; Brazilian Transportation Planning Agency; International Bank for Reconstruction and Development; Texas Research and Development Foundation; GEIPOT; DNER; Brazil. Departamento Nacional de Estradas de Rodagem; United Nations Development Programme; UNDP; Goiás (Brazil : State). Departamento de Estradas de Rodagem; DER-GO; Minas Gerais (Brazil). Departamento de Estradas de Rodagem; DERMG; World Bank; IBRD; TRDF (Empresa Brasileira de Planejamento de Transportes ; United Nations Development Programe, 1981)This Volume records the activities of the PICR User Cost Surveys Group which conducted a large vehicle operating cost survey in Central, Western and Southern Brazil during the period 1975 to 1981. The Group was responsible for the collection and analysis of vehicle maintenance parts and labor costs, tire costs, depreciation and interest charges, and drivers' salaries. In addition, fuel consumption and speed data were collected, the latter when easily available, to serve as consistency checks on the equations derived from experimental data. The Group was also responsible for collecting data on surface roughness, as well as vertical and horizontal geometry characteristics of the routes of those operators registered in the survey. The primary data collection phase ran from 1975 to 1979. and 26 staff members were employed , comprising 14 field workers , 8 clerical assistants and 4 supervisors. More than two years was spent in developing and testing appropriate methodologies, documentation and data p.rocessing systems for the collection, checking, .storage and analysis of both operating cost and highway characteristic data. Contact was made with over 300 companies and more than 2500 vehicles were regis tered for survey membership. Operating cost data were then collected on_ a regular basis from company records. Many difficulties had to be overcome during this period. A number of companies only had records of a few cost components and, where possible, assistance was givento provide the necessary documentation and training to collect missing items. Some companies dropped out of the survey and data collection in others was discontinued because the route characteristics of their vehicles were found to be redundant to the needs of the PICR. Finally, data on over 1600 vehicles derived from 132 companies were available in for preliminary analysis. 1979 Highway characteristics were collected using two specially instrumented vehicles. Roughness was measured with a Maysmeter and calibration maintained through a GM Profilometer and Quarter-Car~Simulator which generated a se~ies of profile~ for a calibration course of highway sections established near Brasflia. Vertical geometry w~s measured using a linear accelerometer connected to a panel scale capable of recording grade changes + of - 1% + to - 12%. Horizontal measurements were taken from a standard aircraft directional gyro compass, mounted in the survey vehicles. Over 85,000 km of roughness and geometry data were collected after measuring more than 36,000 km of operators' routes. After .editing, these data had then to be combined with the vehicle operating cost data so that a single file comprising both dependent and independent variables could be made available for analy~is. The second PICR Phase covered the period 1980 to 1981. The staff was reduced to 5, who were principally engaged in conducting more detailed analyses. The statistical methods employed were rationalized into distinct groups of techniques and advanced econometric procedures employed. An important technique which provided a number of the equations reported herein was the generalized least squares estimation of the error ~omponent model. The latter considers. the company specific error term and the vehicle specific error term which jointly form the components of the unknown random error term consider~d by ordinary least squares techniques. This is one of the first reported application of error components analysis in the field of transportation stu - dies. All the different techniques are detailed in the analysis pro - cedures section of this Volume. The analyst was able to run a selec - tion of these techniques simultaneously on any data set. This made comp~rison of the results and the choice of recommended equations an easier task. Vehicle operating cost information presented for analysis cover the full range of vehicles operating on Brazilian highways. These are grouped into cars_. utility vehicles, buses, medium trucks and heavy articulated vehicles for analysis purposes. The results of the anal - yses of fuel consumption, oil and grease consumption, maintenance parts and labor, tire consumption, depreciation and interest charges and vehicle speed are presented. All five vehicles classes are used in the analyses except for speed which is restricted to cars and buses, and tire costs which are analysed by tire size. The equations recommended in this Volume concentrate on estimating roughness, vehicle age, vehicle characteristics (where appropriate) and geometry effects only when these appear unambiguous. A substantial amount of time was spent estimating the effect of geometry on the various operating cost items and details on the progress made are given in both main text and selected appendices. It is clear that more time is needed to resolve th~ issue. Further small analyses, .together with the findings of the operating cost study in India, presently being analysed, may result in the emergence of a more coherent pattern of the geometry effect on user costs. The PICR User Survey data are the most comprehensive collec~ ed to date and are important both to Brazil, where out-of-date cost tables are widely used and the international research community~ where they .complement the Kenya. Caribbean and India studies. The PICR survey data covers a spectrum of vehicle types and appears to be the only study with a full range of truck classes. The data have now passed through several phases of analysis and the results presented in this Volume. together with the relevant technical memoranda, can be regarded as an interim final form. They are now ready for extensive evaluation in a variety of economic exercises. When they have passed these tests they can be viewed as being in final form for the period ending December 31, 1981. Comparistins are made between total operating costs predict - ed from the various equations recommended in this Volume and prevail - ing transport service rates and tariffs. The results are encouraring and give confidence to the view that the recommended equations will provide better predictions of vehicle operating costs than anything currently used in Brazil. It is recommended that a user cost manual be prepared to allow the results of the PICR survey to be widely disseminated.Item Final Report. Volume 7. Study of pavement maintenance and deteriorationEmpresa Brasileira de Planejamento de Transportes; Brazilian Transportation Planning Agency; International Bank for Reconstruction and Development; Texas Research and Development Foundation; GEIPOT; DNER; Brazil. Departamento Nacional de Estradas de Rodagem; United Nations Development Programme; UNDP; Goiás (Brazil : State). Departamento de Estradas de Rodagem; DER-GO; Minas Gerais (Brazil). Departamento de Estradas de Rodagem; DERMG; World Bank; IBRD; TRDF (Empresa Brasileira de Planejamento de Transportes ; United Nations Development Programe, 1981)Item Inception report. Research concepts and procedures (Report I)Empresa Brasileira de Planejamento de Transportes; Brazilian Transportation Planning Agency; International Bank for Reconstruction and Development; Texas Research and Development Foundation; GEIPOT; DNER; Brazil. Departamento Nacional de Estradas de Rodagem; United Nations Development Programme; UNDP; Goiás (Brazil : State). Departamento de Estradas de Rodagem; DER-GO; Minas Gerais (Brazil). Departamento de Estradas de Rodagem; DERMG; World Bank; IBRD; TRDF (Empresa Brasileira de Planejamento de Transportes ; United Nations Development Programe, 1976-04)A research project is underway in Brazil to develop mathematical models for highway planning. Cost models will be developed relating highway construction, maintenance and utilization. The 42-month project began in September 1975. This initial project report describes the background and previous work in the areas as well as the concepts and proposed methodology for the research. Three basic activities are proposed and described: 1) a series of road user costs surveys to determine operating costs in Brazil, 2) road user and traffic experiments torelate speed and fuel consumption and 3) pavement performance and maintenance experiments. All of these studies will relate construction,maintenance and utilization costs to road construction and design standards, and pavement performance and maintenance. Analysis of results will incorporate previous work sponsored by the World Bank and results of a Transportation Road Research Laboratory study in Kenya. The first results of the current study are expected in 1977. The project is sponsored by the Brazilian Ministry of Transport and the United Nations Development Program. Key words: Highways, highways costs, World Bank, pavement performance, maintenance·, vehicle operating costs, user cost, road user cost, speed, fuel consumption, traffic, United Nation Development Program, GEIPOT, Brazil.Item Final report. Volume 10. Model for simulating traffic (MST)Empresa Brasileira de Planejamento de Transportes; Brazilian Transportation Planning Agency; International Bank for Reconstruction and Development; Texas Research and Development Foundation; GEIPOT; DNER; Brazil. Departamento Nacional de Estradas de Rodagem; United Nations Development Programme; UNDP; Goiás (Brazil : State). Departamento de Estradas de Rodagem; DER-GO; Minas Gerais (Brazil). Departamento de Estradas de Rodagem; DERMG; World Bank; IBRD; TRDF (Empresa Brasileira de Planejamento de Transportes ; United Nations Development Programe, 1981)Item Midterm report. Preliminary results and analyses (Report II)Empresa Brasileira de Planejamento de Transportes; Brazilian Transportation Planning Agency; International Bank for Reconstruction and Development; Texas Research and Development Foundation; GEIPOT; DNER; Brazil. Departamento Nacional de Estradas de Rodagem; United Nations Development Programme; UNDP; Goiás (Brazil : State). Departamento de Estradas de Rodagem; DER-GO; Minas Gerais (Brazil). Departamento de Estradas de Rodagem; DERMG; World Bank; IBRD; TRDF (Empresa Brasileira de Planejamento de Transportes ; United Nations Development Programe, 1977-08)Item Midterm report. Preliminary results and analyses (Summary)Empresa Brasileira de Planejamento de Transportes; Brazilian Transportation Planning Agency; International Bank for Reconstruction and Development; Texas Research and Development Foundation; GEIPOT; DNER; Brazil. Departamento Nacional de Estradas de Rodagem; United Nations Development Programme; UNDP; Goiás (Brazil : State). Departamento de Estradas de Rodagem; DER-GO; Minas Gerais (Brazil). Departamento de Estradas de Rodagem; DERMG; World Bank; IBRD; TRDF (Empresa Brasileira de Planejamento de Transportes ; United Nations Development Programe, 1977-11)This summary of the project midterm report presents achievements and results at Midterm. The accomplishments of the 150- man research team are presented, and include preliminary equations relating roadway characteristics to vehicle speed and fuel consumption. The extent of vehicle overloads in Brazil is highlighted. A program is outlined to update the combined MIT/TRRL/ World Bank Highway Design and Maintenance Standards Model (HDM) .Item Final report. Volume 1. Summary of the ICR researchEmpresa Brasileira de Planejamento de Transportes; Brazilian Transportation Planning Agency; International Bank for Reconstruction and Development; Texas Research and Development Foundation; GEIPOT; DNER; Brazil. Departamento Nacional de Estradas de Rodagem; United Nations Development Programme; UNDP; Goiás (Brazil : State). Departamento de Estradas de Rodagem; DER-GO; Minas Gerais (Brazil). Departamento de Estradas de Rodagem; DERMG; World Bank; IBRD; TRDF (Empresa Brasileira de Planejamento de Transportes ; United Nations Development Programe, 1981)Item Final report. Volume 9, Model of time and fuel consumption (MTC)Empresa Brasileira de Planejamento de Transportes; Brazilian Transportation Planning Agency; International Bank for Reconstruction and Development; Texas Research and Development Foundation; GEIPOT; DNER; Brazil. Departamento Nacional de Estradas de Rodagem; United Nations Development Programme; UNDP; Goiás (Brazil : State). Departamento de Estradas de Rodagem; DER-GO; Minas Gerais (Brazil). Departamento de Estradas de Rodagem; DERMG; World Bank; IBRD; TRDF (Empresa Brasileira de Planejamento de Transportes ; United Nations Development Programe, 1981)Item Final report. Volume 8, Highway costs model (MICR)Empresa Brasileira de Planejamento de Transportes; Brazilian Transportation Planning Agency; International Bank for Reconstruction and Development; Texas Research and Development Foundation; GEIPOT; DNER; Brazil. Departamento Nacional de Estradas de Rodagem; United Nations Development Programme; UNDP; Goiás (Brazil : State). Departamento de Estradas de Rodagem; DER-GO; Minas Gerais (Brazil). Departamento de Estradas de Rodagem; DERMG; World Bank; IBRD; TRDF (Empresa Brasileira de Planejamento de Transportes ; United Nations Development Programe, 1981)Item Final report. Volume 3. InstrumentationEmpresa Brasileira de Planejamento de Transportes; Brazilian Transportation Planning Agency; International Bank for Reconstruction and Development; Texas Research and Development Foundation; GEIPOT; DNER; Brazil. Departamento Nacional de Estradas de Rodagem; United Nations Development Programme; UNDP; Goiás (Brazil : State). Departamento de Estradas de Rodagem; DER-GO; Minas Gerais (Brazil). Departamento de Estradas de Rodagem; DERMG; World Bank; IBRD; TRDF (Empresa Brasileira de Planejamento de Transportes ; United Nations Development Programe, 1981)Item Final report. Volume 6, Study of vehicle behavior and performanceEmpresa Brasileira de Planejamento de Transportes; Brazilian Transportation Planning Agency; International Bank for Reconstruction and Development; Texas Research and Development Foundation; GEIPOT; DNER; Brazil. Departamento Nacional de Estradas de Rodagem; United Nations Development Programme; UNDP; Goiás (Brazil : State). Departamento de Estradas de Rodagem; DER-GO; Minas Gerais (Brazil). Departamento de Estradas de Rodagem; DERMG; World Bank; IBRD; TRDF (Empresa Brasileira de Planejamento de Transportes ; United Nations Development Programe, 1981)