Engineering Commons^™

Application Of Mechanical Vapour Recompression To Industrial Slides Drying, Allan Issangya

Tanzania Journal of Engineering and Technology (TJET)

A positive result of the oil crisis of the seventies is the realisation of energy’s value and the need to use it sparingly. Increasing attention has been focussed on all aspects of industry where fuel oil and gas had played a major role.

Industrial drying, one of the most widely applied unit operations in chemical and process engineering, is a highly energy intensive operation. Studies have identified a number of alternatives for lowering energy consumption in this process through various heat recovery techniques.

Due to the difference in their operating principles steam-heated dryers and air-heated dryers, in most aspects, require …

Optimal Allocation Of Water Among Industries In Dar Es Salaam City, Tanzania, J. I. Matondo

Tanzania Journal of Engineering and Technology (TJET)

Dar es Salaam is the city with the largest number of industries in Tanzania. However, the water demand for these industries is more than the supply. Therefore, there is a water use competing problem among the industries. Dynamic programming technique has been applied to optimally allocate the available water among the industries with the objective of maximizing the net benefits. Results reveal that, industries with the highest net return per unit of water will get the first priority of being allocated water.

Computer Model For Baker’S Yeast Production, A. K. Temu

Tanzania Journal of Engineering and Technology (TJET)

This paper concerns modelling of fermentation for bakers’ yeast (Saccharomyces Cerevisiae) production using sugar cane blackstrap molasses as a feed. The problem constitutes of expressing physical phenomena, mathematically, as function of operating conditions.

The program developed is easy to run and does not cost much in terms of preparations. With this program different operating conditions were tested and results show that available equations are not exhaustive. Thus more research is recommended.

Effect Of The Variations Of The Mobile Dislocation Density On The Thermally Activated Cyclic Deformation Behavior, J. S. Mshana

Tanzania Journal of Engineering and Technology (TJET)

The application of the transition state theory of rate processes to describe tension-tension, strain controlled cyclic deformation BEHAVIOUR was extended to describe the effect of the variations of the mobile dislocation density on the cyclic deformation BEHAVIOUR. It was shown from the derived constitutive relation that due to the net increase in the mobile dislocation density during strain controlled cyclic deformation the stress change per cycle (or in function of time) increases.

Development Of A Spray Drought Cooling Tower, O. K. Kaunde

Tanzania Journal of Engineering and Technology (TJET)

ABSTRACT A noval type direct contact cooling tower has been proposed in which the gas or air entering the tower is drawn by the ejector action of the sprays through which the feed water is admitted. The advantage offered by this type of tower is that it eliminates the usages of fan, thus saving the capital cost and power to drive it.

Entrainment of air by water was studied in a laboratory cooling tower and the result of the entire experiment indicate that the development of a spray drought tower is a feasible practice.

A General Correction For Spontaneous Potential Well Logs In Fresh Water, Cary L. Mcconnell

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A generalized empirical relationship was found which corrects spontaneous potential (SP) readings from well logs run in freshwater wells. The function was found by correlating measured and calculated spontaneous potentials. The calculated values are based on actual measured ionic content of groundwaters and are fully corrected for environmental effects and ion species. Without the empirical relationship the electrically equivalent to an NaCl solution resistivity, Rwe, is generally too low for fresh waters when computed with existing commercially available functions. The low Rwe makes the water appear saltier than it really is. One hundred sixty-two (162) individual formations from one hundred …

Estimation Of In-Situ Compression Index Of Contaminated Clays Using The Electrical Method, Prasanna Ratnaweera

Theses

For contaminated clay soils, it has been found that current testing methods to determine compressibility characteristics do not truly identify the physico-chemiral interaction present in the soil-pore fluid-electrolyte system. Most methods are virtually impracticable due to various reasons such as evaporation of pore-fluid, difficulty of handling toxic chemicals, etc. Also, destructive test methods may not maintain in-situ conditions while testing.

The electrical properties of soils, the dielectric dispersion in particular is considered to represent the amount of physico-chemical interaction present in the soil-pore fluid-electrolyte system. For uncontaminated soils, correlations between the dielectric dispersion and the slope of the isotropic consolidation …

Design Of Automotive Structural Components Using High Strength Sheet Steels Structural Strength Of Cold-Formed Steel I-Beams And Hat Sections Subjected To Web Crippling Load, Shin-Hua Lin, Ling-En Hsiao, Chi-Ling Pan, Wei-Wen Yu

CCFSS Library (1939 - present)

INTRODUCTION When cold-formed steel beam webs are subjected to partial edge loading, they may fail by web crippling rather than bending of the beam. Web crippling is caused by a highly localized intensity of the load or reaction. Because of the complexity of the web crippling behavior, empirical expressions are presently used for the design of cold-formed steel beams in buildings and automotive structural components to prevent web crippling. 1,2,3. The research on the structural behavior of cold-formed steel beam webs subjected to web crippling has been conducted at Cornell University and the University of Missouri-Rolla (UMR) under the sponsorship …

Whole-Building Moisture Experiments And Data Analysis. Draft Task 1 Final Report, Milestone #219. February 5, 1988. 91 P., Florida Solar Energy Center, Adel A. Kamel

FSEC Energy Research Center®

For four months (August -November) in 1987 whole -building moisture capacitance experiments were done on a townhouse in Cocoa, Florida. The experiments were designed to: 1. Observe the response of a building to imposed moisture flux 2. Determine the moisture storage capacity of the building and furnishings 3. Evaluate simple models designed to predict the response of room air humidity ration to pulses of moisture 4. Assess two innovative approaches to cooling (off-peak cooling and DESRAD) The results of the tests indicated that moisture storage in the furnishings is much greater than moisture storage in the air. The bare building …

Welcome And Opening Remarks, Multiple Authors

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.

Past Proceedings: First International Conference On Case Histories In Geotechnical Engineering (1984): Vol. Iv, Multiple Authors

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.

Past Proceedings: First International Conference On Case Histories In Geotechnical Engineering (1984): Vol. I, Multiple Authors

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.

A Low Rise Hospital Development On Restored Opencast Fill, W. M. Kilkenny

International Conference on Case Histories in Geotechnical Engineering

An extensive low-rise hospital development has taken place since 1982 on a former opencast coal mining site 30 years after working and restoration. The clay and shale fill some 20 metres deep was placed without systematic compaction. Five separate site investigations have been carried out at different times during the last 20 years and a detailed engineering geological mapping exercise was completed in 1977. Drainage works and the main buildings in Scheme 1 and 2 have been monitored during and after construction. Significant settlements have occurred requiring some remedial work. A surcharge and inundation trial has been undertaken prior to …

A Modified Field Infiltrometer Test For Clay Liners, G. S. Laird, W. B. Lozier, A. M. Gurevich

International Conference on Case Histories in Geotechnical Engineering

Regulatory agencies are looking more frequently to in situ field hydraulic conductivity tests for the assessment of a liner's compliance to a specified hydraulic conductivity. Most field tests have evaluated hydraulic conductivity by measuring the infiltration rate of the liner. The infiltration rate can be used to arrive at a hydraulic conductivity value if the hydraulic boundary conditions of the test can be identified or if the head loss at different depths can be measured. A test fill of a clay liner was evaluated for its saturated vertical hydraulic conductivity. This paper discusses the use of eight tensiometers to measure …

Hazardous Waste Disposal Site Hydrogeologic Characterization, S. M. Testa

International Conference on Case Histories in Geotechnical Engineering

A major hazardous waste disposal facility near Arlington, Oregon serving the Pacific Northwest, Canada, and Alaska maintains numerous favorable environmental characteristics for siting of a hazardous waste disposal facility. The risk of contamination as a result of potential leakage from a waste management unit via primary pathways to surface water, groundwater or by direct contact and/or ingestion is thus reasonably low. However, these same characteristics which make the site most suitable for hazardous waste disposal often conflict with: 1) the demonstration of the groundwater monitoring system's ability to adequately perform immediate leak detection monitoring as mandated under the Resource Conservation …

Implementation Of Remedial Measures To Contain A Pcb Spill, M. D. Huag, J. Atwater, R. B. Knight, P. Kozicki, A. Lissey

International Conference on Case Histories in Geotechnical Engineering

A large spill of Polychlorinated Biphenols (PCB's) occurred at Federal Pioneer Limited's Regina Plant in 1976. The City of Regina is underlain by a relatively shallow aquifer which supplies a significant proportion of its drinking water. A remedial measures plan was developed to contain this spill within the boundaries of the site and clean up any contamination which had spread to adjacent property. The remedial measures plan developed involved limiting or reversing the normal downward hydraulic gradient. The three principle measures introduced to accomplish this reversal included the construction of a cutoff wall around the site, installation of a thick …

A Geological Appraisal Of Slope Instability And Proposed Remedial Measures At Kaliasaur Slide On National Highway, Garwal Himalaya, G. S. Mehrotra, R. K. Bhandari

International Conference on Case Histories in Geotechnical Engineering

For over six decades Kaliasaur landslide (Lat. 30° 14' 30" N, Long. 78° 55' 50" E) is a nightmare on the Hardwar-Badrinath road in the Garhwal Himalaya. Located on a sharp bend on the left bank of river Alaknanda, it has emerged as a multi-tier repetitive major landslide, retrogressive in nature. Both surficial and deep seated movements have been monitored. The sliding in the upper layers have been predominantly in the colluvium but where interfaces of quartzite and shale participates, the sliding surfaces have been better defined and discrete. In the present paper, the authors have highlighted the geological, geomorphological …

Construction Of Hydel Power House In Weak Rocks, K. K. Kapoor, S. C. Patodiya

International Conference on Case Histories in Geotechnical Engineering

Geological uncertainties have always played an important role in planning of a hydel power house. This paper presents case study of a power house which was subjected to major revisions in its planning due to inherent instabilities in rock slopes. Initially the power house was planned with service bay and other facilities on its left hand side, but the weak and instable slopes and sliding of large rock masses necessitated its thorough revision by bringing service bay and other facilities to its right hand side along with addition of many new features and flattening of slopes. There were many alternatives …

Evaluation Of The Site Investigation And Construction Related Aspects Of The Milwaukee's Crosstown Deep Tunnel, R. C. Ilsley, S. B. Fradkin, E. F. Shorey

International Conference on Case Histories in Geotechnical Engineering

The excavation of the 21,300 foot long, 32.33 foot diameter Crosstown Phase I Tunnel was completed by tunnel boring machine at an average rate of 108 feet per 3 shift day. No geologic conditions were encountered which were sufficiently adverse to impede the work. The geotechnical report combined with contract provisions prevented the unusual conditions encountered from becoming issues that delayed the work. It is probable that the monetary aspects related to these unusual conditions can be equitably resolved using the geotechnical data “base line” portrayed in the geotechnical report.

Foundation Investigation And Treatment For The Main Dam, Italpu Project, John G. Cabrera

International Conference on Case Histories in Geotechnical Engineering

After selection of the site for this major hydroelectric project on the Upper Parana River, initial borings in the river bed revealed an extremely fractured zone near the base of the dense basalt flow on which the main dam would be founded. This zone was later seen to correspond to intersecting faults beneath the river bed, therefore upon dewatering the river channel several exploratory tunnels were driven parallel and perpendicular to the dam axis, foreseeing their incorporation into an elaborate "shear key" system to prevent renewed movements of the shear zones. The tunnel grid was backfilled with concrete through holes …

Geo-Engineering Problems In The Spillway Foundations And Their Treatment At Guhai Reservoir Project In Gujurat, India, D. M. Pancholi, K. E. Modhwadia, P. H. Vaidya

International Conference on Case Histories in Geotechnical Engineering

During the initial stage of construction of a 23 m high composite dam across the Guhai river, the downstream dipping sedimentary rock sequence of conglomerate, sandstone and shale resting unconformably over quartzite and schist was encountered as a surprise during the excavation of the foundation. Besides, an 8 to 8.5 m wide major fault zone along with three minor faults running across the dam axis were also noticed. Extensive subsurface investigations to study the nature and characteristics of sedimentary rocks, fault zones, etc. met with in the foundations were undertaken concurrently with the construction activity. As a result, the construction …

Lithotectonic Landslides And Hazards In Parts Of Garhwal-Kumaon Himalayas, R. S. Mithal

International Conference on Case Histories in Geotechnical Engineering

Landslides produce an awesome picture of the hill sides with steep scarred, hollowed and gullied geomorphic features devoid of vegetation particularly between the major thrust zones. A look on the tectono-stratigraphic map of the region with marked major tectonic features like the Main Central Thrust (MCT), North Almora Thrust (NAT) and South Almora Thrust (SAT) indicates that the region is highly prone to landslides and is affected by repeated tectonic and orogenic processes. These factors with the nature of the rocks, climate and the heavy monsoon rains are responsible for sculpturing the region. The mountain features and the valley slopes …

Simultaneous Velocity Measurements With Uniaxial Loading On Weak Sandstone From Iraq, Zuhair Rammo Fattohi

International Conference on Case Histories in Geotechnical Engineering

Transit pulse wave times through a weakly cemented sandstone rock being measured on prismatic specimens with and without initial plane of weakness, which is uniaxially loaded at different stages. The velocity, Elastic moduli bulk compressibility, and vertical strain were calculated for each loading level. Results have shown, that such rock properties have changed dramatically. Thus they should be considered thoroughly for any engineering evaluation in such rock type.

Slope Stability Evaluation For An Existing Steep Cut In Weathered Volcanics, Hong Kong, J. K. P. Kwong, L. J. Endicott, A. C. Lumsden

International Conference on Case Histories in Geotechnical Engineering

This case study concerns an investigation of a major existing soil slope. It is a 60m (197 ft) high cutting slope, at 40 degrees to 60 degrees to the horizontal, exhibiting a considerably greater degree of stability than was obtained by a series of geotechnical investigations and analyses. The common practice of correlation between widely spaced borings is shown to be inappropriate at this site because of the highly variable ground conditions. Rather, the comprehensive geological comprehensive engineering investigation carried out has enabled a detailed appreciation of the distribution and nature of weathered materials at the site. Transitional materials with …

Study Of Some Debris Avalanches In Garwal Himalaya, India, H. C. Nainwal, Y. P. Sundriyal, C. Prasad

International Conference on Case Histories in Geotechnical Engineering

This study was carried out in the Alaknanda - Dhauliganga catchment area, located in the north and northeast of Joshimath in the Garfiwal Himalaya. The snow fields, cirques and the related glaciers are located above the altitude approximate 4000 meters, while the river valley have a mean altitude of around 2000 meters. The strategic roads viz. Joshimath-Badrinath and Joshimath-Nitipass pass through this area with a number of villages along with their cultivated land are located along the roads. These roads are often blocked on huge debris avalanches not only damage the road, but also the cultivated land and forests. The …

Subsidence Movements And Structural Damage Related To An Abandoned Coal Mine, Y. P. Chugh, K. Chandrashekhar, R. J. Missavage

International Conference on Case Histories in Geotechnical Engineering

An area in southwestern Illinois has been experiencing surface and subsurface movements with associated damage to surface structures. The area is underlain by an abandoned, partially extracted room-and-pillar underground coal mine. Instrumentation included TDR (Time Domain Reflectometry), Inclinometers, Sondex, Tiltplates, and precision land surveys. This paper presents the results of a 16-month cooperative study between the Department of Mining Engineering at SIUC and a local coal company.

Behaviour Of Inginimitiya Embankment Dam, T. Sivapatham

International Conference on Case Histories in Geotechnical Engineering

The prominent component of the Inginimitiya Reservoir Project is the Inginirnitiya Darn, This dam with a maximum height of 58 ft. is essentially a homogeneous earthfill embankment except for the slope protection, filter and drainage arrangement. The cut-off for the foundation seepage and the provisions made in the design for seepage control are described in this paper. The reservoir when partially impounded for the first time in 1983 "boiling" (bubbling with fines heaving up) was observed on the downstream at different locations close to the toe of the embankment between chainages 71 and 75. This reach when investigated revealed the …

Coastal Bluff Retreat At Big Lagoon, California, R. C. Chaney, D. C. Tuttle

International Conference on Case Histories in Geotechnical Engineering

Big Lagoon, located 30 miles north of Eureka, California is formed behind a bay barrier built across the mouth of a drowned river valley. To the south of the bay the beach follows rising wave cut slightly cemented sand and gravel sea cliffs and terminates at the south end of Agate Beach. The retreat of these sea cliffs and its effect on property development along the top of the cliff is the focus of the paper. Measurements of bluff retreat in this area have been documented extensively from November 1941 to March 1986 through ground surveys and air photos. Review …

Comprehensive Seepage Assessment: Beaver Dam, Arkansas, J. L. Llopis, C. M. Deaver, D. K. Butler, S. C. Hartung

International Conference on Case Histories in Geotechnical Engineering

A general philosophy of the role of engineering geology and engineering geophysics in seepage assessment is presented. Practical application of this philosophy is illustrated by a case history. A large dike continues to have anomalous seepage in spite of pre-construction and postconstruction grouting. The dike is founded over a graben of cavernous limestone with about a 200-ft. vertical offset along the bounding fault zones, which are horizontally separated by about 1000 ft. Objectives of the seepage assessment program were to define the geological and hydrological conditions beneath the dike in sufficient detail to allow rational remedial planning. Integration of results …

Construction Problems With An Earth And Rockfill Dam, Hasan Hejazi

International Conference on Case Histories in Geotechnical Engineering

Earth and rockfill dams became popular in the 1960's primarily because of increased heights of dams, poor foundation conditions that rule out concrete dams, and vast improvements in excavation and vibratory compaction equipment. Such equipment made excavation and processing of rock and placement of rockfill much more economical than in the past. Due to the unique composition and the critical zone construction of earth and rockfill dams, they are subject to different types of problems. Some problems may be discovered and corrected during construction. Such problems cause changes in contract documents and delays in work, as in the case of …