Kurdistan Regional Government Ministry of Higher Education and

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Kurdistan Regional Government Ministry of Higher Education and Scientific Research Salahaddin University College Of

Kurdistan Regional Government Ministry of Higher Education and Scientific Research Salahaddin University College Of Engineering Civil Engineering Department Hydro-mechanical behaviour of stone powder used for Dam Core Prepared by: Soz Arsalan salh Youns Mohammed Mahmood Supervised by : Dr. Ahmad. M. Hassan 2020 -2019 Aysha Kamal Aziz

Introduction

Introduction

Objectives of the research • To perform physical, hydraulic and mechanical routine tests on

Objectives of the research • To perform physical, hydraulic and mechanical routine tests on stone powder in the soil lab to confirm that whether it acceptable to use it as a dam core or not. • If the stone powder not suitable to be used as a dam core how this issue can be managed.

Dam Core : Core dams are a membrane build within an embankment dam to

Dam Core : Core dams are a membrane build within an embankment dam to form the impermeable barrier, the balance of the dam being provide to insure stability.

Materials Used In Dam Core It may be a natural materials such as clay

Materials Used In Dam Core It may be a natural materials such as clay or prepared materials such as cement or asphaltic concrete, or metal, plastic rubber, etc.

Application of dam core • It provides water tightness to the dam. • it

Application of dam core • It provides water tightness to the dam. • it controls the seepage flow through the body of the dam.

Soil dispersion Is a process that occurs in soils by water. In soil layers

Soil dispersion Is a process that occurs in soils by water. In soil layers where clays are saturated it may be wash away, this can lead to a variety of soil quality problems such as piping.

Permeability of Embankment Soil embankment constructed on reservoir, pond or river. • hydraulic safety

Permeability of Embankment Soil embankment constructed on reservoir, pond or river. • hydraulic safety of soil embankment is mainly governed by the permeability of embankment soil. • It is practically important to measure permeability and quality a state of safety of the soil embankment

 • Gradation and plasticity of embankment soils are considered to be important than

• Gradation and plasticity of embankment soils are considered to be important than placement moisture condition.

Shear Strength Of embankment One of the primary factors that control the stability of

Shear Strength Of embankment One of the primary factors that control the stability of earthen embankments is the shear strength of embankment fill soils.

Piping of embankment and foundation of dams • Piping through the body of the

Piping of embankment and foundation of dams • Piping through the body of the dam: • Piping through the Foundation:

Methodology

Methodology

Methodology Laboratory tests a) b) c) d) e) f) Atterberg limits Specific gravity Compaction

Methodology Laboratory tests a) b) c) d) e) f) Atterberg limits Specific gravity Compaction test Permeability test Direct shear test Pin hole test

Atterberg limits: Determine the liquid and plastic limit of stone powder samples for identification

Atterberg limits: Determine the liquid and plastic limit of stone powder samples for identification and classification of stone powder.

Specific gravity: The determination of specific gravity of soil will help in the calculation

Specific gravity: The determination of specific gravity of soil will help in the calculation of void ratio, degree of saturation and other different soil properties.

Compaction test : The aim of the test is to establish the maximum dry

Compaction test : The aim of the test is to establish the maximum dry density MDD and optimum moisture content OMC that may be attained for a given soil with a standard amount of compactive effort. The results of the test was used to prepare samples for direct shear, pinhole and permeability tests.

Permeability test : The aim of the test is to establish the maximum dry

Permeability test : The aim of the test is to establish the maximum dry density MDD and optimum moisture content OMC that may be attained for a given soil with a standard amount of compactive effort. The results of the test was used to prepare samples for direct shear, pinhole and permeability tests.

Direct shear test: Direct shear test is a laboratory test used by geotechnical engineers

Direct shear test: Direct shear test is a laboratory test used by geotechnical engineers to measure the shear strength parameters (c and ф) of soil.

Pinhole test : The pinhole test has been developed for the purpose of identifying

Pinhole test : The pinhole test has been developed for the purpose of identifying dispersive of materials such as soil.

Test Results

Test Results

Atterberg limit results Liquid Limit (LL) Plastic Limit (PL) Plasticity Index (PI) 22. 2%

Atterberg limit results Liquid Limit (LL) Plastic Limit (PL) Plasticity Index (PI) 22. 2% 0. 0% 22. 2%

Specification of Atterberg limits for earth fill (Fell et al, 2015)

Specification of Atterberg limits for earth fill (Fell et al, 2015)

Standard Proctor test results

Standard Proctor test results

Permeability test results

Permeability test results

Direct shear test results c = 80 k. Pa, ф = 21 o

Direct shear test results c = 80 k. Pa, ф = 21 o

Pinhole test results Head (cm) Flow flow rate Turbidity From side Remarks very Dar

Pinhole test results Head (cm) Flow flow rate Turbidity From side Remarks very Dar Modrately Barely Completely slightly Dark dark k Dark visible clear 5 18 38 100 ml. 10 25 25 50 50 50 sec. (ml/sec) 29. 82 0. 3353 31. 94 0. 7827 35 0. 7143 36. 04 0. 6937 21. 32 1. 1726 44. 31 1. 1284 55. 13 0. 9069 14. 33 3. 4892 √ √ √ √ suddenly from completely clear cheanges to very dark √

Conclusions: Experimental results on the stone powder demonstrated that • the Atterberg limits (LL

Conclusions: Experimental results on the stone powder demonstrated that • the Atterberg limits (LL and PI) were not within specifications (Fell et al, 2015). • In addition the results of Pinhole test also showed that (where the head was 100 cm) a sudden erosion (piping) happened. Based on the experimental results on the stone powder, it can be concluded that the stone powder if only used as a material for dam core will case catastrophic problems Recommendation: It is recommended that the stone powder has to be mixed with another material or materials to improve its physical and hydraulic properties.

Reference • Strength and Deformation of Rock fill Material Based on Large-Scale Triaxial Compression

Reference • Strength and Deformation of Rock fill Material Based on Large-Scale Triaxial Compression Tests. I: Influences of Density and Pressure(Yang Xiao, S. M. ASCE; Hanlong Liu; Yumin Chen; and Jingshan Jiang) • Laboratory Tests for Evaluation of the Actions Limiting the Progression of Internal Erosion in Zoned Dams” Fell et al 2008. • Design of small dam , USBR, 1987. • Rock Earth Dams: Engineering problems of design and construction, by john wiley. • AZOJETE vol. 7. 2010”Brink el al(1984)”