The document summarizes a study on the stability analysis of an existing 21m high earth dam in India called Bhimdi earth dam. The study analyzed the stability of the dam by changing parameters like berm width and the position of filter drains using GeoStudio software. The factors of safety were computed for various scenarios and compared to the existing design. Strengthening the dam with anchors and nails also increased the factors of safety. Changing the berm width from 5m to 3m decreased the factor of safety from 2.43 to 2.25 on the downstream side. On the upstream side, a narrower berm width and adding anchors and nails also increased the factors of safety.
this presentation describes in details the sinking operation of well foundations in different conditions and situations. the content here is suitable only for basic knowledge and educational purposes.
The document discusses various types of loads and pressures that act on underground tunnels, including:
1) Earth/rock pressures and water pressure are the most important potential loads. Live loads from surface traffic can usually be neglected.
2) Dimensions of tunnel sections must account for overburden weight (geostatic pressure) or loosening pressure (weight of loosened rock zone).
3) Lateral pressures, bottom pressures, and rock pressures are discussed. Several theories for estimating vertical and lateral loads are presented, including those by Bierbaumer, Terzaghi, and Tsimbaryevitch.
4) Rock pressures depend on factors like the quality of rock, stresses/strains around the
Regarding Types of Foundation, Methods, Uses of different types of foundation at different soil properties. Methods of construction of different types of foundation, Codal Provisions etc.
This document discusses various aspects of tunnel construction including definitions, purposes, factors affecting construction, major tunnels in India, shapes of tunnels, geological surveys, design considerations, construction methods, and conclusions. It defines a tunnel as an underground passageway dug through surrounding soil or rock and enclosed except at entrances and exits. Common construction methods described are cut-and-cover, tunnel boring machine (TBM), shield technique, pipe jacking, and sprayed concrete. Design considerations include alignment, tunnel lining, groundwater control, ventilation, and investigation.
This presentation is useful for GTU students in Building Construction subject in Subsurface investigation the popular topic in syllabus, this includes more images which will help to students & researchers for same.
The document discusses foundations and site exploration for determining soil properties. It describes the functions of foundations, including distributing loads, preventing uneven settling, and providing stability. Subsurface investigation methods are outlined, such as trial pits, probing, geophysical tests, and borings used to determine soil types and properties at varying depths. The document also discusses determining the bearing capacity of soils using methods like plate load tests and penetration tests.
this presentation describes in details the sinking operation of well foundations in different conditions and situations. the content here is suitable only for basic knowledge and educational purposes.
The document discusses various types of loads and pressures that act on underground tunnels, including:
1) Earth/rock pressures and water pressure are the most important potential loads. Live loads from surface traffic can usually be neglected.
2) Dimensions of tunnel sections must account for overburden weight (geostatic pressure) or loosening pressure (weight of loosened rock zone).
3) Lateral pressures, bottom pressures, and rock pressures are discussed. Several theories for estimating vertical and lateral loads are presented, including those by Bierbaumer, Terzaghi, and Tsimbaryevitch.
4) Rock pressures depend on factors like the quality of rock, stresses/strains around the
Regarding Types of Foundation, Methods, Uses of different types of foundation at different soil properties. Methods of construction of different types of foundation, Codal Provisions etc.
This document discusses various aspects of tunnel construction including definitions, purposes, factors affecting construction, major tunnels in India, shapes of tunnels, geological surveys, design considerations, construction methods, and conclusions. It defines a tunnel as an underground passageway dug through surrounding soil or rock and enclosed except at entrances and exits. Common construction methods described are cut-and-cover, tunnel boring machine (TBM), shield technique, pipe jacking, and sprayed concrete. Design considerations include alignment, tunnel lining, groundwater control, ventilation, and investigation.
This presentation is useful for GTU students in Building Construction subject in Subsurface investigation the popular topic in syllabus, this includes more images which will help to students & researchers for same.
The document discusses foundations and site exploration for determining soil properties. It describes the functions of foundations, including distributing loads, preventing uneven settling, and providing stability. Subsurface investigation methods are outlined, such as trial pits, probing, geophysical tests, and borings used to determine soil types and properties at varying depths. The document also discusses determining the bearing capacity of soils using methods like plate load tests and penetration tests.
- There are four main methods to measure the load carrying capacity of piles: static methods, dynamic formulas, in-situ penetration tests, and pile load tests.
- The ultimate load capacity (Qu) of an individual pile or pile group equals the sum of the point resistance (Qp) at the pile tip and the shaft resistance (Qs) developed along the pile shaft through friction between the soil and pile.
- Meyerhof's method is commonly used to calculate Qp in sand based on the effective vertical pressure at the pile tip multiplied by the bearing capacity factor Nq.
1. The document discusses different types of settlement in shallow foundations, including immediate/elastic settlement, primary consolidation settlement, and secondary consolidation settlement.
2. It provides methods for calculating each type of settlement, making use of theories of elasticity, consolidation test data, and parameters like compression index.
3. Settlement predictions are generally satisfactory but better for inorganic clays; the time rate of consolidation settlement is often poorly estimated.
The document summarizes different techniques for retaining deep excavations, including contiguous piles, secant piles, sheet piling, diaphragm walls, soldier piles with lagging, and presents case studies of their use. It discusses techniques such as contiguous piles with soil anchors used for the IT Tower Lahore project requiring excavation to a depth of 65 feet, and contiguous piling with 9 layers of anchors for the Alamgir Tower Lahore project requiring excavation to 85 feet. It also summarizes the use of slurry walls for the large Washington Convention Center project requiring excavation up to 55 feet deep.
tunnel lining may be permanent or temporary based upon their use and requirement. design of lining is done in two parts one is temporary or initial lining design and other is permanent design of the lining. empirical and theoretical methods are major design methods.
This document provides an overview of deep excavation techniques. It discusses earth retaining walls used to restrain soil during deep excavations. Common types of retaining walls include braced walls, sheet pile walls, pile walls, diaphragm walls, and reinforced concrete walls. Supporting elements like ground anchors and struts are also discussed. Specific techniques covered include contiguous piles, secant piles, sheet piles, and the vertical soldiers and horizontal lagging method.
This document discusses soil mechanics concepts related to lateral earth pressure. It defines active and passive earth pressures and describes Rankine's theory and assumptions for calculating lateral pressures on retaining walls. Equations are provided for determining active and passive earth pressure coefficients and distributions for cohesionless and cohesive soils. The effects of groundwater, surcharges, and sloping backfills are also examined. Sample problems are included to calculate lateral earth pressures and forces on retaining walls for different soil and loading conditions.
This document will help you learn an introductory part and some detailed information on Shallow Foundations. As I am presenting this document to you I wish you all a Happy learning arena. It is highly recommended for students taking a bachelor degree in Civil Engineering, also it is a good document for students who are doing final touches for their examinations.
Bearing Capacity of Shallow Foundation.faizanNoor8
This document discusses the bearing capacity of shallow foundations. It defines bearing capacity as the maximum average contact pressure between the foundation and soil without causing shear failure. Shallow foundations are those where the depth is less than the width, and are commonly used as they are economical and easy to construct. Terzaghi's bearing capacity theory states that the ultimate bearing capacity of a shallow foundation depends on the cohesion of the soil, overburden pressure, and unit weight of the soil. It provides equations to calculate the ultimate bearing capacity for square, continuous, and circular footings based on this theory.
This document provides an overview of laboratory and field testing methods for rocks. It discusses index property tests such as unit weight, porosity, permeability, electrical resistivity, and sonic velocity that are used to characterize and classify rocks. It also describes mechanical property tests like unconfined compressive strength testing, triaxial testing, point load strength testing, and beam bending tests. Common field testing methods mentioned include pressuremeter testing, in-situ direct shear testing, and hydraulic fracturing. The document provides details on sample preparation, equipment used, procedures, and how to calculate and interpret results for different rock property tests.
BOUSSINESQ THEORY
VERTICAL STRESS DUE TO POINT LOAD
TABLE FOR VALUES OF BOUSSINESQ’S COEFFICIENT (퐼_퐵)
SOME POINTS FOR USING THE BOUSSINESQ’S EQUATION.
LIMITATIONS OF BOUSSINESQ’S SOLUTION.
This document discusses various methods of boring into soil and rock to obtain samples at different depths. It describes auger boring, which uses hand or powered soil augers to drill holes. It also outlines shell and auger boring, wash boring using pressurized water, percussion boring using repeated blows, and rotary drilling which rotates a cutting bit to extract cylindrical core samples. The purpose of boring is to gather reliable subsurface information for engineering design and construction projects.
Soil exploration methods and soil investigation reportAnjana R Menon
Soil exploration involves site investigations through methods like boreholes, test pits, and geophysical tests. This provides critical information on ground conditions like soil type, bearing capacity, and water levels for foundation design of structures. The objectives are to evaluate soil properties, predict issues, ensure safety, and select suitable construction methods. A proper exploration program involves reconnaissance, preliminary, and sometimes detailed investigations using appropriate testing and sampling methods based on the project size and soil variability.
1. The document discusses concepts related to seepage, piping failure, and remedial measures for earth dams. It then defines consolidation as the reduction in volume of saturated clay that occurs over a long time through the expulsion of water from voids when the clay is loaded externally.
2. The types of consolidation are described as immediate compression, primary consolidation, and secondary compression. Primary consolidation is the portion of settlement due to the resistance of water flowing under induced hydraulic gradients.
3. A consolidation test procedure is outlined where soil samples are loaded in increments in an oedometer device and dial gauge readings are taken to determine deformation rates and amounts. Calculations are described to obtain coefficients of consolidation and compression
This document discusses soil arching in granular soils. It begins with an introduction to soil arching and how it occurs when stress is transferred from yielding soil to rigid adjacent zones. It then discusses experimental evidence of arching from previous studies. Finally, it covers the mechanism of arching, factors that affect it, theories about arching stresses and shapes, and limit state analysis used to analyze arching.
The standard penetration test (SPT) involves driving a split spoon sampler into the ground using a 140 lb hammer dropped 30 inches. The number of blows required to penetrate each 6 inch interval is recorded, and the penetration resistance value N is the sum of the blows over the second and third intervals. This test is commonly used to obtain bearing capacity and estimate soil properties like density and shear strength. It is performed whenever the soil stratum changes and at intervals of no more than 1.5 meters.
This document discusses different types of earth and rockfill dams. It describes rolled fill dams which are constructed by compacting soil in thin layers. Homogeneous dams consist of a single material throughout while zoned dams have distinct core, shell, and filter zones. Diaphragm dams contain an impervious core like a thin wall. Key elements of earth dam design include the top width, freeboard, slopes, central core, and downstream drainage system.
This document summarizes the procedures for conducting a pile load test to determine the load carrying capacity of a pile. The test involves installing a test pile between two anchor piles and applying incremental loads through a hydraulic jack while monitoring settlement. Loads are applied until the pile reaches twice its safe load or a specified settlement. A load-settlement curve is plotted to determine the ultimate load and safe load based on settlement criteria. The test provides values for maximum load, permissible working load, and pile settlement under different loads.
This document provides an introduction to foundation engineering and different types of foundations. It discusses shallow foundations, which have a depth to width ratio of less than 4, including spread, strip, continuous, combined and raft foundations. It also discusses deep foundations, which have a depth to width ratio greater than 4, such as piles and drilled shafts. The document further explains bearing capacity and settlement criteria for foundations. It provides details on Terzaghi's and Skempton's bearing capacity theories and includes examples of calculating ultimate and allowable bearing capacities.
The document provides information on shallow foundations, including definitions, design criteria, methods for determining bearing capacity, and modes of failure. It discusses Prandtl's analysis, Rankine's analysis, and Terzaghi's bearing capacity theory. Terzaghi's theory assumes a shallow strip footing fails along a composite shear surface through five zones: an elastic zone under the footing, two radial shear zones, and two linear shear zones forming a triangular shape. The theory is used to derive an expression for ultimate bearing capacity considering the soil's shear strength properties.
Benching provides a collaborative workspace that is well-suited for team-oriented work. It encourages discussion, informal learning, and accessibility between coworkers. Benching is most effective for cohesive work groups, mobile workers, classrooms, design studios, and highly mobile consultant teams - environments that emphasize teamwork, socialization, and frequent interaction between coworkers. While flexible for collaboration, benching may not be appropriate when quiet, privacy, or deep concentration are needed.
Benching provides a collaborative workspace that is well-suited for team-oriented workstyles. It encourages discussion, informal learning, and accessibility between coworkers. Benching is most effective for cohesive work groups, mobile workers, classrooms, design studios, and highly mobile consultant teams - environments that emphasize teamwork, socialization, and frequent interaction between members. While flexible for collaboration, benching may not support tasks requiring deep concentration or privacy.
- There are four main methods to measure the load carrying capacity of piles: static methods, dynamic formulas, in-situ penetration tests, and pile load tests.
- The ultimate load capacity (Qu) of an individual pile or pile group equals the sum of the point resistance (Qp) at the pile tip and the shaft resistance (Qs) developed along the pile shaft through friction between the soil and pile.
- Meyerhof's method is commonly used to calculate Qp in sand based on the effective vertical pressure at the pile tip multiplied by the bearing capacity factor Nq.
1. The document discusses different types of settlement in shallow foundations, including immediate/elastic settlement, primary consolidation settlement, and secondary consolidation settlement.
2. It provides methods for calculating each type of settlement, making use of theories of elasticity, consolidation test data, and parameters like compression index.
3. Settlement predictions are generally satisfactory but better for inorganic clays; the time rate of consolidation settlement is often poorly estimated.
The document summarizes different techniques for retaining deep excavations, including contiguous piles, secant piles, sheet piling, diaphragm walls, soldier piles with lagging, and presents case studies of their use. It discusses techniques such as contiguous piles with soil anchors used for the IT Tower Lahore project requiring excavation to a depth of 65 feet, and contiguous piling with 9 layers of anchors for the Alamgir Tower Lahore project requiring excavation to 85 feet. It also summarizes the use of slurry walls for the large Washington Convention Center project requiring excavation up to 55 feet deep.
tunnel lining may be permanent or temporary based upon their use and requirement. design of lining is done in two parts one is temporary or initial lining design and other is permanent design of the lining. empirical and theoretical methods are major design methods.
This document provides an overview of deep excavation techniques. It discusses earth retaining walls used to restrain soil during deep excavations. Common types of retaining walls include braced walls, sheet pile walls, pile walls, diaphragm walls, and reinforced concrete walls. Supporting elements like ground anchors and struts are also discussed. Specific techniques covered include contiguous piles, secant piles, sheet piles, and the vertical soldiers and horizontal lagging method.
This document discusses soil mechanics concepts related to lateral earth pressure. It defines active and passive earth pressures and describes Rankine's theory and assumptions for calculating lateral pressures on retaining walls. Equations are provided for determining active and passive earth pressure coefficients and distributions for cohesionless and cohesive soils. The effects of groundwater, surcharges, and sloping backfills are also examined. Sample problems are included to calculate lateral earth pressures and forces on retaining walls for different soil and loading conditions.
This document will help you learn an introductory part and some detailed information on Shallow Foundations. As I am presenting this document to you I wish you all a Happy learning arena. It is highly recommended for students taking a bachelor degree in Civil Engineering, also it is a good document for students who are doing final touches for their examinations.
Bearing Capacity of Shallow Foundation.faizanNoor8
This document discusses the bearing capacity of shallow foundations. It defines bearing capacity as the maximum average contact pressure between the foundation and soil without causing shear failure. Shallow foundations are those where the depth is less than the width, and are commonly used as they are economical and easy to construct. Terzaghi's bearing capacity theory states that the ultimate bearing capacity of a shallow foundation depends on the cohesion of the soil, overburden pressure, and unit weight of the soil. It provides equations to calculate the ultimate bearing capacity for square, continuous, and circular footings based on this theory.
This document provides an overview of laboratory and field testing methods for rocks. It discusses index property tests such as unit weight, porosity, permeability, electrical resistivity, and sonic velocity that are used to characterize and classify rocks. It also describes mechanical property tests like unconfined compressive strength testing, triaxial testing, point load strength testing, and beam bending tests. Common field testing methods mentioned include pressuremeter testing, in-situ direct shear testing, and hydraulic fracturing. The document provides details on sample preparation, equipment used, procedures, and how to calculate and interpret results for different rock property tests.
BOUSSINESQ THEORY
VERTICAL STRESS DUE TO POINT LOAD
TABLE FOR VALUES OF BOUSSINESQ’S COEFFICIENT (퐼_퐵)
SOME POINTS FOR USING THE BOUSSINESQ’S EQUATION.
LIMITATIONS OF BOUSSINESQ’S SOLUTION.
This document discusses various methods of boring into soil and rock to obtain samples at different depths. It describes auger boring, which uses hand or powered soil augers to drill holes. It also outlines shell and auger boring, wash boring using pressurized water, percussion boring using repeated blows, and rotary drilling which rotates a cutting bit to extract cylindrical core samples. The purpose of boring is to gather reliable subsurface information for engineering design and construction projects.
Soil exploration methods and soil investigation reportAnjana R Menon
Soil exploration involves site investigations through methods like boreholes, test pits, and geophysical tests. This provides critical information on ground conditions like soil type, bearing capacity, and water levels for foundation design of structures. The objectives are to evaluate soil properties, predict issues, ensure safety, and select suitable construction methods. A proper exploration program involves reconnaissance, preliminary, and sometimes detailed investigations using appropriate testing and sampling methods based on the project size and soil variability.
1. The document discusses concepts related to seepage, piping failure, and remedial measures for earth dams. It then defines consolidation as the reduction in volume of saturated clay that occurs over a long time through the expulsion of water from voids when the clay is loaded externally.
2. The types of consolidation are described as immediate compression, primary consolidation, and secondary compression. Primary consolidation is the portion of settlement due to the resistance of water flowing under induced hydraulic gradients.
3. A consolidation test procedure is outlined where soil samples are loaded in increments in an oedometer device and dial gauge readings are taken to determine deformation rates and amounts. Calculations are described to obtain coefficients of consolidation and compression
This document discusses soil arching in granular soils. It begins with an introduction to soil arching and how it occurs when stress is transferred from yielding soil to rigid adjacent zones. It then discusses experimental evidence of arching from previous studies. Finally, it covers the mechanism of arching, factors that affect it, theories about arching stresses and shapes, and limit state analysis used to analyze arching.
The standard penetration test (SPT) involves driving a split spoon sampler into the ground using a 140 lb hammer dropped 30 inches. The number of blows required to penetrate each 6 inch interval is recorded, and the penetration resistance value N is the sum of the blows over the second and third intervals. This test is commonly used to obtain bearing capacity and estimate soil properties like density and shear strength. It is performed whenever the soil stratum changes and at intervals of no more than 1.5 meters.
This document discusses different types of earth and rockfill dams. It describes rolled fill dams which are constructed by compacting soil in thin layers. Homogeneous dams consist of a single material throughout while zoned dams have distinct core, shell, and filter zones. Diaphragm dams contain an impervious core like a thin wall. Key elements of earth dam design include the top width, freeboard, slopes, central core, and downstream drainage system.
This document summarizes the procedures for conducting a pile load test to determine the load carrying capacity of a pile. The test involves installing a test pile between two anchor piles and applying incremental loads through a hydraulic jack while monitoring settlement. Loads are applied until the pile reaches twice its safe load or a specified settlement. A load-settlement curve is plotted to determine the ultimate load and safe load based on settlement criteria. The test provides values for maximum load, permissible working load, and pile settlement under different loads.
This document provides an introduction to foundation engineering and different types of foundations. It discusses shallow foundations, which have a depth to width ratio of less than 4, including spread, strip, continuous, combined and raft foundations. It also discusses deep foundations, which have a depth to width ratio greater than 4, such as piles and drilled shafts. The document further explains bearing capacity and settlement criteria for foundations. It provides details on Terzaghi's and Skempton's bearing capacity theories and includes examples of calculating ultimate and allowable bearing capacities.
The document provides information on shallow foundations, including definitions, design criteria, methods for determining bearing capacity, and modes of failure. It discusses Prandtl's analysis, Rankine's analysis, and Terzaghi's bearing capacity theory. Terzaghi's theory assumes a shallow strip footing fails along a composite shear surface through five zones: an elastic zone under the footing, two radial shear zones, and two linear shear zones forming a triangular shape. The theory is used to derive an expression for ultimate bearing capacity considering the soil's shear strength properties.
Benching provides a collaborative workspace that is well-suited for team-oriented work. It encourages discussion, informal learning, and accessibility between coworkers. Benching is most effective for cohesive work groups, mobile workers, classrooms, design studios, and highly mobile consultant teams - environments that emphasize teamwork, socialization, and frequent interaction between coworkers. While flexible for collaboration, benching may not be appropriate when quiet, privacy, or deep concentration are needed.
Benching provides a collaborative workspace that is well-suited for team-oriented workstyles. It encourages discussion, informal learning, and accessibility between coworkers. Benching is most effective for cohesive work groups, mobile workers, classrooms, design studios, and highly mobile consultant teams - environments that emphasize teamwork, socialization, and frequent interaction between members. While flexible for collaboration, benching may not support tasks requiring deep concentration or privacy.
Landslide Control Measures at Jumja Slide,Bhutanskpradhan
The document discusses landslide control measures implemented at the Jumja landslide in Bhutan. The 50+ year old landslide regularly damaged the Phuentsholing-Thimpu road. Stabilization efforts from 2000-2006 included retaining walls, drainage improvements, and slope stabilization. A long-term investigation recommended additional measures like rock bolting, benching, gabion walls, check dams and exploring a tunnel option to fully address the persistent landslide issues.
A comparison on slope stability analysis of aydoghmoosh earth damdgjd
1. The document compares slope stability analysis of the Aydoghmoosh Earth Dam in Iran using limit equilibrium methods, finite element analysis, and finite difference methods.
2. Safety factors calculated using the simplified Bishop method and finite element analysis were similar at 1.494 and 1.596, respectively.
3. The finite difference method produced a safety factor of 1.79, around 12% higher than the finite element method. This is because the finite element method accounts for elasticity modulus in its calculations.
STABILITY OF SLOPESSEEPAGE CONTROL MEASURES AND SLOPE PROTECTION
a finite slope AB, the stability of which is to be analyzed.
The method Consists of assuming a number of trial slip circles, and finding the factor of safety of each.
The circle corresponding to the minimum factor of safely is the critical slip circle.
Let AD be a trial slip circle, with r as the radius and O as the centre of rotation
Let W be the weight of the soil of the wedge ABDA of unit thickness, acting through the centroid G.
The driving moment MD will be equal to W x, where x, is the distance of line of action of W from the vertical line passing through the centre of rotation O.
if cu is the unit cohesion, and l is the length of the slip arc AD, the shear resistance developed along the slip surface will be equal to cu • l, which act at a radial distance r from centre of rotation O.
When slip is imminent in a cohesive soil, a tension crack will always DevelOP by the top surface of the slope along which no shear resistance can develop,
The depth of tension crack is given by
The effect of tension crack is to shorten the arc length along which shear resistance gets mobilised to AB' and to reduce the angle δ to δ'.
The length of the slip arc to be taken in the computation of resisting force is only AB', since tension crack break the continuity at B'.
The weight of the sliding wedge is weight of the area bounded by the ground surface, slip circle arc AB' and the tension crack.
The main components of an earth dam are as follows :
1. Impervious core
2. Pervious shell
3. Filter
4. Rock toe
5. U/S slope protection
6. D/S slope protection
7. Cutoff
core shouldnot be less than 3 m and its height should be 1 m more than the maximum water levelin the reservoir.
The upstream pervious zone provides free drainage during sudden drawdown. ,
Usually following types of filters are provided :
(1) Toe filter
(2) Horizontal drainage filter (blanket)
(3) Chimney drains
Such a filter is sometimes known as inverted filter or reverse filter.
Rock toe keeps the phreatic line well within the section and also facilitates drainage.
The following measures are taken to protect the slope.
(1) Rock riprap
(2) Concrete pavement
(3) Steel facing
(4) Bituminous pavement
(5) Precast concrete blocks
Cut off is required to
(1) reduce loss of stored water through foundation and abutments
(2) Prevent sub surface erosion by piping.
Cutoff may be provided in the following ways :
• by providing concrete cutoff wall
• by providing cutoff trench filled with impervious material
• by driving sheet pile
• by curtain grouting
Hydraulic failures .... 40%
Seepage failures…….. 30%
Structural failures .... 30%
(1) Overtopping
(2) Erosion of u/s slope by waves
(3) Erosion of d/s slope by wind and rain
(4) Erosion of d/s toe
(5) Frost action
(1) Overtopping = the design flood is under estimated.
spillway capacity is not adequet
spillway gates are not properly operated
free board is not sufficient
excessive settlement of the foundation and dam
(2) Erosion of u/s slope by waves = The waves developed near the top water surface due to the winds, try to notch out the soil from the upstream face and may even, sometimes, cause the slip of the upstream slope.
Upstream stone pitching or riprap should, therefore, be provided to avoid such failures.
(3) Erosion of d/s slope by wind and rain = The rainwater flowing down the slope; may result in the formation of 'gullies' on the downstream slope thus damaging the dam which may generally lead to partial failure of the dam or in some cases it may cause complete failure of the dam.
Erosion of d/s toe : = Toe erosion may occur due to two reasons :
erosion due to tail water
erosion due to cross currents that may come from spillway buckets.
Frost action : = If the earth dam is located at a place where the temperature falls below the freezing point, frost may form in the pores of the soil in the earth dam.
When there is heaving, the cracks may form in the soil. This may lead to dangerous seepage and consequent failure.
Seepage failures : = Seepage failures may occur due to the following causes :
(1) Piping through the foundation
(2) Piping through the dam
(3) Sloughing of d/s toe
Structural failures :=
Structural failures in earth dams are generally shear failures leading to sliding of the tents or the foundations.
(1) u/s and d/s slope failures due to construction pore pressures
(2) u/s slope failure due to sudden drawdown
(3) D/s slope failure due to steady seepage
(4) Foundation slide due to spontaneous liquefaction
(5) Failure due to earthquake
(6) Failure by spreading
(7) Slope protection failures
(8) Failure due to damage caused by borrowing animals
(9) Failure due to holes caused by leaching of water soluable salts
Criteria for safe Design of Earth Dam :
Section of an Earth Dam :
The design of an earth dam essentially consists of determining such a cross section
the dam which when constructed with the available materials will fulfill its required
tion with adequate safety. Thus there are two aspects of the design of an earth dam.
The document discusses the design of embankment dams. It defines embankment dams as dams constructed of natural materials like earth or rockfill. It describes the different types of embankment dams including homogeneous dams, zoned dams, and diaphragm dams. It also discusses important design considerations for embankment dams like controlling seepage, providing internal drainage, and ensuring the shear strength of the soil is sufficient to resist failure. Pore water pressure in saturated soils is identified as an important factor that reduces the effective stress and shear strength of soils in embankment dams.
Soil nailing is a technique used to reinforce and strengthen existing ground.Soil nailing consists of installing closely spaced bars into a slope or excavation as construction proceeds from top down.It is an effective and economical method of constructing retaining wall for excavation support, support of hill cuts, bridge abutments and high ways.This process is effective in cohesive soil, broken rock, shale or fixed face conditions.
The document defines key mining terminology used in open pit mine design including: bench, bench height, bench slope, berm, overall pit slope angle, haul roads, angle of repose, subcrop/ore depth, pre-production stripping, ultimate pit limits, pit scheduling, stripping ratio, single working bench, shovel in working bench, two working benches, pit sequence, and section of pit sequence. It provides illustrations of these concepts and how an example mine may develop its pit over time through sequential pushbacks.
This document provides an overview of hydraulic structures and classifications of dams. It discusses:
1) Different types of dams classified by function (storage, detention, diversion), design (overflow, non-overflow), structure (gravity, arch, buttress, embankment), and materials (rigid, non-rigid).
2) Characteristics and components of earth dams including homogeneous, zoned, and diaphragm types.
3) Characteristics of rock fill dams and combined earth and rock fill dams.
4) Advantages and disadvantages of gravity dams, arch dams, and buttress dams constructed of concrete.
Earthen dams are constructed using natural materials like clay, sand, gravel and rock. They are designed based on principles of soil mechanics. There are two main types - homogeneous and zoned. Zoned dams have an impervious core and outer shells. Components include the core, shells, rock toe, pitching, berms and drains. Stability requires the seepage line be within the downstream slope with minimum 2m cover. Common causes of failure are hydraulic (overtopping, erosion), seepage (piping through core or foundations) and structural issues like cracking. Proper design and construction can prevent these failures.
Effect of coarse aggregate characteristics on strength properties of highIAEME Publication
This document summarizes a study on the effect of coarse aggregate characteristics on the strength properties of high-performance concrete. The study used two types of coarse aggregates and tested concrete cubes to determine compressive strength at 56 days. The key findings were:
1) Concrete made with Type A aggregate achieved higher compressive strengths, up to 62.5 MPa, compared to concrete with Type B aggregate, up to 28.62 MPa.
2) Type A aggregate concrete had better workability as measured by slump and slump flow tests.
3) Aggregate type can significantly influence the compressive strength and workability of normal concrete mixtures. The highest strengths were obtained using Type A coarse aggregate.
Interference of adjoining rectangular footings on reinforced sandiaemedu
This document discusses the interference effects of adjoining rectangular footings on reinforced sand. Model tests were conducted with different footing sizes and spacings resting on a geogrid-reinforced sand bed. The results show that bearing capacity increases with footing size and decreases with increased spacing between footings. Providing continuous geogrid reinforcement under closely-spaced footings improves their bearing capacity compared to isolated footings. An efficiency factor is used to quantify the influence of spacing, with lower factors indicating bearing capacity is more influenced at smaller spacings. In conclusion, geogrid reinforcement and reduced spacing between footings increases their bearing capacity when constructed on sand.
Interference of adjoining rectangular footings on reinforced sandiaemedu
This document discusses a study on the interference of adjoining rectangular footings on reinforced sand. Laboratory model tests were conducted to evaluate the effects of two adjacent footings on bearing capacity and settlement for various footing sizes and spacings on sand reinforced with geogrid. The tests observed that providing a continuous geogrid reinforcement layer under closely spaced footings improved their bearing capacity. Parameters like footing dimensions, spacing, and reinforcement placement depth were varied to analyze their impact.
Design Parameters and Fluid Interaction of Amphibious StructuresIRJET Journal
- The document discusses the design of an amphibious structure that can withstand floods by rising due to buoyancy.
- Key design parameters for amphibious structures are identified, including hydrostatic load, hydrodynamic load, buoyant force, and stability.
- A 3-storey primary health care centre is designed as a case study. The superstructure is designed as a steel frame, while the substructure consists of pontoons and resisting jackets.
- Pontoon depth and thickness are optimized to displace enough water to support the structure. Jackets are designed to restrict movement from fluid forces.
Virtual instrumentation for measurement of strain using thin film strain gaug...iaemedu
This document summarizes the development of a virtual instrumentation system for measuring strain using thin film strain gauge sensors. Thin film strain gauges were deposited on a cantilever beam using sputtering deposition. A LabVIEW program was developed to acquire and plot the resistance changes in the strain gauges under different loads. The system uses National Instruments hardware including a data acquisition board and signal conditioning modules to measure microstrains with errors within 0.5%. Thin film strain gauges offer improved performance over conventional foil gauges and this system can be applied to applications requiring precision strain measurements.
Virtual instrumentation for measurement of strain using thin film strain gaug...iaemedu
This document describes the development of a virtual instrumentation system for measuring strain using thin film strain gauge sensors. Thin film nickel-chromium strain gauges were deposited on a beryllium copper cantilever substrate using DC magnetron sputtering. The strain gauges were connected to a National Instruments data acquisition system using a signal conditioning unit. A LabVIEW virtual instrument was created to acquire and display the strain measurements in engineering units as weights were added to the cantilever. The indicated strain measurements matched the calculated strain values to within 0.5% error, demonstrating the effectiveness of the virtual instrumentation system for measuring micro-strain.
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IRJET- Effect of Different Soil Conditions on Seismic Response of Multi-Store...IRJET Journal
The document summarizes a study analyzing the seismic response of a 9-story irregular reinforced concrete frame structure with varying soil conditions (hard, medium, and soft soil) using STAAD Pro software. Three models (M1, M2, M3) with the same structural parameters except soil type are analyzed using the equivalent static method. The response of each model is examined in terms of maximum story displacement, column stresses, and required steel quantity. The objective is to check the stability of the models under different soil conditions according to Indian codes and standards.
COMPARISON OF MAXIMUM DRY DENSITY OPTIMUM MOISTURE CONTENT AND STRENGTH OF GR...IAEME Publication
The project aims at comparing the various compaction characteristics of granular soils in selecting the appropriate method of soil stabilization. The difference in the behavior of granular soils to standard and modified proctor test was studied.
IRJET-Study on Behaviour of Retrofitted RC Beam-Column Exterior Joints with G...IRJET Journal
This document presents a study on retrofitting reinforced concrete beam-column exterior joints with glass fiber reinforced polymer (GFRP) wrapping to improve their seismic performance. Three 1/5th scale specimens of a beam-column joint from a prototype 5-story building were tested: one unretrofitted control specimen and two specimens retrofitted with one or two layers of GFRP wrapping after being loaded to 70% of their ultimate capacity. Testing showed that the retrofitted specimens had increased load capacity, energy absorption, and ductility compared to the unretrofitted joint. Specifically, the single layer retrofitted joint was able to regain its original strength and had 60% more energy absorption than the control, while the double layer retrofitted
Development and characterization of thin film nichrome strain gauge sensor fo...iaemedu
This document describes the development and characterization of a thin film nickel-chromium strain gauge sensor for load applications. Researchers designed and fabricated the strain gauge on a beryllium copper cantilever beam substrate using sputter deposition. They characterized the gauge's resistance change in response to applied loads and determined its gauge factor. Testing showed the strain gauge sensor responded linearly to deflection and mass loads up to 550 mg. The researchers concluded thin film nichrome strain gauges can be used in micro-machined load sensors.
Development and characterization of thin film nichrome strain gauge sensor fo...iaemedu
This document summarizes the development and characterization of a thin film nickel-chromium strain gauge sensor for load applications. Key steps included:
1. Designing and sputter depositing nickel-chromium strain gauges on a beryllium copper cantilever beam substrate. An insulating polymer layer was applied between the substrate and gauges.
2. Connecting the strain gauges in a Wheatstone bridge configuration to measure load by deflecting the cantilever beam end and recording resistance changes.
3. Analyzing the sensor parameters by measuring the linear fractional resistance changes of the strain gauges under different loads and determining their gauge factors.
AN INVESTIGATION ON MINE OVERBURDEN DUMP SLOPE STABILITYIRJET Journal
This document summarizes a study that investigated the stability of mine overburden dump slopes in Dhanbad, India. Samples were collected from mine sites and tested in a lab to determine engineering properties. A numerical model was developed using finite element analysis software to simulate slope stability under varying conditions. The study found that adding geogrid reinforcement can improve slope stability and allow steeper slopes or greater heights. Specifically, stability decreased with steeper slopes and taller slopes but was optimized with 3-7 layers of geogrid reinforcement, beyond which there were diminishing returns for stability.
Comparative Study of Ferrocement Panels Under Blast Loading by Finite Element...IRJET Journal
This document analyzes the behavior of ferrocement panels under blast loading using finite element analysis in ANSYS. Ferrocement panels with 2-layer and 3-layer mesh configurations and thicknesses of 18mm and 25mm were modeled and subjected to blast loads at varying standoff distances. The results found that panels with greater thickness and mesh layers experienced less deformation and stress under blast loads. Specifically, the 25mm thick 3-layer panel showed 46% less deformation and 58% less strain compared to the 18mm thick 2-layer panel. Therefore, thicker ferrocement panels with more mesh layers provide better blast resistance and should be used for structures at high risk of explosions.
Study on rutting and surface behaviour of urban flexible pavementeSAT Publishing House
This document summarizes a study on rutting and surface behavior of urban flexible pavements. Rutting measurements were taken at 8 bus shelter locations along two stretches of road. Rutting depths ranged from 30mm to 90mm, exceeding the maximum allowable depth of 20mm. 5 alternatives to address the rutting were proposed: stone matrix asphalt, mastic asphalt, glass fiber grid reinforcement, paver blocks, and rigid pavement. Data analysis showed rutting decreased initially with observations but later varied abruptly. The alternatives were to be evaluated using software for damage analysis and cost comparison.
IRJET- A Study on Seismic Evaluation of RC Framed Structures on Varying Perce...IRJET Journal
This document summarizes a study on the seismic evaluation of reinforced concrete framed structures with varying percentages of diaphragm discontinuity, with and without shear walls. 12 models of a G+10 story building were developed in ETABS with 0%, 8.33%, 16.66%, and 33.32% diaphragm openings. The models were analyzed using equivalent static analysis and response spectrum analysis according to Indian standards. Results for base shear, story shear, story displacement, and story drift ratios were obtained and discussed. It was found that providing shear walls, especially at the corners and periphery of openings, helped reduce seismic demands on the structure compared to models without shear walls.
Stability Analysis of Bridge Structures Using Modal AnalysisIRJET Journal
The document summarizes a study on analyzing the stability of bridge structures using modal analysis. Modal analysis was conducted on a bridge model using ANSYS simulation software. Three materials were analyzed: concrete, silicone rubber, and neoprene rubber. For each material, the mode shapes, natural frequencies, and mass participation factors were determined. The results found that for concrete and silicone rubber, the critical region with maximum deformation was the crash barrier. For neoprene rubber, the maximum deformation occurred at the bearing region. The modal analysis provided vibration characteristics and identified regions susceptible to resonance for different bridge materials.
Multi-channel analysis of Surface Wave (MASW) profiling for delineation of su...IRJET Journal
This document summarizes a study that used Multi-channel Analysis of Surface Waves (MASW) profiling to delineate subsurface stratigraphy around the Kolkata High Court building in India. MASW data was collected along 6 profiles near the building to determine shear wave velocity with depth. The data showed that within 15 meters of the surface, shear wave velocities were low (<200 m/s), indicating soft soil that could cause settlement. Below 15 meters, velocities increased, indicating denser soil. This helps explain cracking observed in the heritage building, likely due to soft near-surface soil conditions. The study classified the near-surface soils as NEHRP Site Class F and deeper soils as Class E, providing information on
IRJET- Soil Mass Movement with Recent Deluge in Kerala as BackdropIRJET Journal
This document discusses soil mass movement in Kerala, India following severe flooding in July 2018. Laboratory tests were conducted on soil samples from an affected site, including sieve analysis, direct shear testing, and specific gravity tests. Slope stability analysis was performed using the Swedish circle method and PLAXIS software. The analyses found a safety factor of 8.163 without anchors and 8.445 with anchors installed. The study concluded that poor construction practices and soil deterioration from prolonged flooding contributed to failures. Anchors were recommended to stabilize slopes and prevent further landslides in severely affected areas.
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Tech transfer making it as a risk free approach in pharmaceutical and biotech iniaemedu
Tech transfer is a common methodology for transferring new products or an existing
commercial product to R&D or to another manufacturing site. Transferring product knowledge to the
manufacturing floor is crucial and it is an ongoing approach in the pharmaceutical and biotech
industry. Without adopting this process, no company can manufacture its niche products, let alone
market them. Technology transfer is a complicated, process because it is highly cross functional. Due
to its cross functional dependence, these projects face numerous risks and failure. If anidea cannot be
successfully brought out in the form of a product, there is no customer benefit, or satisfaction.
Moreover, high emphasis is in sustaining manufacturing with highest quality each and every time. It
is vital that tech transfer projects need to be executed flawlessly. To accomplish this goal, risk
management is crucial and project team needs to use the risk management approach seamlessly.
Integration of feature sets with machine learning techniquesiaemedu
This document summarizes a research paper that proposes a novel approach for spam filtering using selective feature sets combined with machine learning techniques. The paper presents an algorithm and system architecture that extracts feature sets from emails and uses machine learning to classify emails and generate rules to identify spam. Several metrics are identified to evaluate the efficiency of the feature sets, including false positive rate. An experiment is described that uses keyword lists as feature sets to train filters and compares the proposed approach to other spam filtering methods.
Effective broadcasting in mobile ad hoc networks using gridiaemedu
This document summarizes a research paper that proposes a new grid-based broadcasting mechanism for mobile ad hoc networks. The paper argues that flooding approaches to broadcasting are inefficient and cause network congestion. The proposed approach divides the network into a hierarchical grid structure. When a node needs to broadcast a message, it sends the message to the first node in the appropriate grid, which is then responsible for updating and forwarding the message within that grid. Simulation results showed the grid-based approach outperformed other broadcasting protocols and was more reliable, efficient and scalable.
Effect of scenario environment on the performance of mane ts routingiaemedu
The document analyzes the effect of scenario environment on the performance of the AODV routing protocol in mobile ad hoc networks (MANETs). It studies AODV performance under different scenarios varying network size, maximum node speed, and pause time. The performance is evaluated based on packet delivery ratio, throughput, and end-to-end delay. The results show that AODV performs best in some scenarios and worse in others, indicating that scenario parameters significantly impact routing protocol performance in MANETs.
Adaptive job scheduling with load balancing for workflow applicationiaemedu
This document discusses adaptive job scheduling with load balancing for workflow applications in a grid platform. It begins with an abstract that describes grid computing and how scheduling plays a key role in performance for grid workflow applications. Both static and dynamic scheduling strategies are discussed, but they require high scheduling costs and may not produce good schedules. The paper then proposes a novel semi-dynamic algorithm that allows the schedule to adapt to changes in the dynamic grid environment through both static and dynamic scheduling. Load balancing is incorporated to handle situations where jobs are delayed due to resource fluctuations or overloading of processors. The rest of the paper outlines the related works, proposed scheduling algorithm, system model, and evaluation of the approach.
This document summarizes research on transaction reordering techniques. It discusses transaction reordering approaches based on reducing resource conflicts and increasing resource sharing. Specifically, it covers:
1) A "steal-on-abort" technique that reorders an aborted transaction behind the transaction that caused the abort to avoid repeated conflicts.
2) A replication protocol that attempts to reorder transactions during certification to avoid aborts rather than restarting immediately.
3) Transaction reordering and grouping during continuous data loading to prevent deadlocks when loading data for materialized join views.
The document discusses semantic web services and their challenges. It provides an overview of semantic web technologies like WSDL, SOAP, UDDI, and OIL which are used to build semantic web services. The semantic web architecture adds semantics to web services through ontologies written in OWL and DAML+OIL. Key approaches to semantic web services include annotation, composition, and addressing privacy and security. However, semantic web services still face challenges in achieving their full potential due to issues in representation, reasoning, and a lack of real-world applications and data.
Website based patent information searching mechanismiaemedu
This document summarizes a research paper on developing a website-based patent information searching mechanism. It discusses how patent information can be used for technology development, rights acquisition and utilization, and management information. It describes different types of patent searches including novelty, validity, infringement, and state-of-the-art searches. It also evaluates and compares two major patent websites, Delphion and USPTO, in terms of their search capabilities and features.
Revisiting the experiment on detecting of replay and message modificationiaemedu
This document summarizes a research paper that proposes methods for detecting message modification and replay attacks in ad-hoc wireless networks. It begins with background on security issues in wireless networks and types of attacks. It then reviews existing intrusion detection systems and security techniques. Related work that detects attacks using features from the media access control layer or radio frequency fingerprinting is also discussed. The paper aims to present a simple, economical, and platform-independent system for detecting message modification, replay attacks, and unauthorized users in ad-hoc networks.
1) The document discusses the Cyclic Model Analysis (CMA) technique for sequential pattern mining which aims to predict customer purchasing behavior.
2) CMA calculates the Trend Distribution Function from sequential patterns to model purchasing trends over time. It then uses Generalized Periodicity Detection and Trend Modeling to identify periodic patterns and construct an approximating model.
3) The Cyclic Model Analysis algorithm is applied to further analyze the patterns, dividing the domain into segments where the distribution function is increasing or decreasing and applying the other techniques recursively to fully model the cyclic behavior.
Performance analysis of manet routing protocol in presenceiaemedu
This document analyzes the performance of different routing protocols in a mobile ad hoc network (MANET) under hybrid traffic conditions. It simulates a MANET with 50 nodes moving at speeds up to 20 m/s using the AODV, DSDV, and DSR routing protocols. Traffic included both constant bit rate and variable bit rate sources. Results found that AODV had lower average end-to-end delay and higher packet delivery ratios than DSDV and DSR as the percentage of variable bit rate traffic increased. AODV also performed comparably under both low and high node mobility scenarios with hybrid traffic.
Performance measurement of different requirements engineeringiaemedu
This document summarizes a research paper that compares the performance of different requirements engineering (RE) process models. It describes three RE process models - two existing linear models and the authors' iterative model. It also reviews literature on common RE activities and issues with descriptive models not reflecting real-world practices. The authors conducted interviews at two Indian companies to model their RE processes and compare them to the three models. They found the existing linear models did not fully capture the iterative nature of observed RE processes.
This document proposes a mobile safety system for automobiles that uses Android operating system. The system has two main components: a safety device and an automobile base unit. The safety device allows users to monitor the vehicle's location on a map, check its status, and control functions remotely. It communicates with the base unit in the vehicle using GPRS. The base unit collects data from sensors, determines the vehicle's GPS location, and can execute control commands like activating the brakes or switching off the engine. The document provides details on the design and algorithms of both components and includes examples of Java code implementation. The goal is to create an intelligent, secure and easy-to-use mobile safety system for vehicles using embedded systems and Android
Efficient text compression using special character replacementiaemedu
The document describes a proposed algorithm for efficient text compression using special character replacement and space removal. The algorithm replaces words with non-printable ASCII characters or combinations of characters to compress text files. It uses a dynamic dictionary to map words to their symbols. Spaces are removed from the compressed file in some cases to further reduce file size. Experimental results show the algorithm achieves better compression ratios than LZW, WinZip 10.0 and WinRAR 3.93 for various text file types while allowing lossless decompression.
The document discusses agile programming and proposes a new methodology. It provides an overview of existing agile methodologies like Scrum and Extreme Programming. Scrum uses short sprints to define tasks and deadlines. Extreme Programming focuses on practices like test-first development, pair programming, and continuous integration. The document notes drawbacks like an inability to support large or multi-site projects. It proposes designing a new methodology that combines the advantages of existing methods while overcoming their deficiencies.
Adaptive load balancing techniques in global scale grid environmentiaemedu
The document discusses various adaptive load balancing techniques for distributed applications in grid environments. It first describes adaptive mesh refinement algorithms that partition computational domains using space-filling curves or by distributing grids independently or at different levels. It also discusses dynamic load balancing using tiling and multi-criteria geometric partitioning. The document then covers repartitioning algorithms based on multilevel diffusion and the adaptive characteristics of structured adaptive mesh refinement applications. Finally, it discusses adaptive workload balancing on heterogeneous resources by benchmarking resource characteristics and estimating application parameters to find optimal load distribution.
A survey on the performance of job scheduling in workflow applicationiaemedu
This document summarizes a survey on job scheduling performance in workflow applications on grid platforms. It discusses an adaptive dual objective scheduling (ADOS) algorithm that takes both completion time and resource usage into account for measuring schedule performance. The study shows ADOS delivers good performance in completion time, resource usage, and robustness to changes in resource performance. It also describes the system architecture used, which includes a planner and executor component. The planner focuses on scheduling to minimize completion time while considering resource usage, and can reschedule if needed. The executor enacts the schedule on the grid resources.
A survey of mitigating routing misbehavior in mobile ad hoc networksiaemedu
This document summarizes existing methods to detect misbehavior in mobile ad hoc networks (MANETs). It discusses how routing protocols assume nodes will cooperate fully, but misbehavior like packet dropping can occur. It describes several techniques to detect misbehavior, including watchdog, ACK/SACK, TWOACK, S-TWOACK, and credit-based/reputation-based schemes. Credit-based schemes use virtual currencies to provide incentives for nodes to forward packets, while reputation-based schemes track nodes' past behaviors. The document aims to survey approaches for mitigating the impact of misbehaving nodes in MANET routing.
A novel approach for satellite imagery storage by classifyiaemedu
This document presents a novel approach for classifying and storing satellite imagery by detecting and storing only non-duplicate regions. It uses kernel principal component analysis to reduce the dimensionality and extract features of satellite images. Fuzzy N-means clustering is then used to segment the images into blocks. A duplication detection algorithm compares blocks to identify duplicate and non-duplicate regions. Only the non-duplicate regions are stored in the database, improving storage efficiency and updating speed compared to completely replacing existing images. Support vector machines are used to categorize the non-duplicate blocks into the appropriate classes in the existing images.
A self recovery approach using halftone images for medical imageryiaemedu
This document summarizes a proposed approach for securely transferring medical images over the internet using visual cryptography and halftone images. The approach uses error diffusion techniques to generate a halftone host image from the grayscale medical image. Shadow images are then created from the halftone host image using visual cryptography algorithms. When stacked together, the shadow images reveal the secret medical image. The halftone host image also contains an embedded logo that can be extracted to verify the integrity of the reconstructed image without a trusted third party.