Project Design Agency

Tender for Geotechnical Investigation and Testing of the Various Construction Materials for Detail Design and Construction of Machalgo Irrigation and Hydropower Project, Paktia Province

Paktia, Afghanistan

Date: 24 April 201

Tender for geotechnical investigation and testing of the various Construction Materials 1. Scope of works 

Review the available geotechnical information.

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Describe the general geology of the area and prepare a geological map

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Investigate any potential flaws for construction of Machalgo dam site

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Investigate sources for dam construction materials.

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Undertake geotechnical investigations for the dam foundations, spillway structure, diversion arrangements

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Assess the stability of slopes around the reservoir rim.

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Detailed seismic design and analyses of Machalgo project site and considered the effect of all the historically recorded earthquakes located within a radius of 300 km from the site to determine the mean return periods for the Probable Maximum Acceleration (PGA); the annual probability of being exceeded for a specified value of the PGA, and uniform ground acceleration spectra

2. Sampling and testing to be provided for exploration of rocky foundation and abutments of dam and appurtenant structures and rock quarries The most important properties to be tested for design of rock fill dams, its foundation and abutments, are as bellow:  Gradation  Compacted Unit Weight  Permeability  Compressibility  Strength and Deformation  Chemical and mineral analysis of material located in foundation and abutments of dam.  Bearing capacity of foundation materials  Durability  Hydraulic Conductivity of rock fill  RQD  Water absorption of rock

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 Maximum molecular water content  Uniaxial compressive strength of rock material  Spacing of discontinuities  Condition of discontinuities  Ground water conditions  Orientation of discontinuities 3. Sampling and testing to be done for soil foundations and abutments of dam and appurtenant structures and soil quarries A) Sand i) Specific gravity, ii) Bulk density, void ratio iii) Moisture content, iv) Absorption value, v) Presence of deleterious materials, vi) Gradation analysis. vii) Bulking of sand Note. 5 samples for each test from each sand quarry. B) Aggregates a) Specific gravity, b) Bulk density, void ratio c) Field Moisture content, d) Water Absorption value, e) (i) Aggregate crushing strength (ii) Aggregate impact value, f) Loss Angeles Abrasion value, g) Flakiness-index, h) Elongation-index, i) Presence of deleterious materials, Page 3

j) Alkali aggregate reactivity k) Soundness of aggregate, l) Gradation analysis. Note. 2 Samples for each test from each quarry source. C) Disturbed soil samples from Borrow areas: a) Specific gravity a)

Void ratio

b) Optimum Water content c)

Consistency limits /Atterberg Limits/

d) Standard Proctor Dry Density tests e) Gradation analysis and incase of silt and clay soil Hydrometric analysis for fraction of the soil passing below 75 micron to 1 micron. f)

Tri-axial shear test for Effective Shear parameters (C’ and Φ’) with pore pressure measurements g) Permeability tests h) Soil classification Gradation analysis and incase of silt and clay soil Hydrometric analysis for fraction of the soil passing below 75 micron to 1 micron. Note. 1) 246 samples for each test For items a to e & h) 2) for item (f & g) only 20 samples may be tested D) Undisturbed soil samples from dam site a) Specific gravity b) Void ratio tests c) In situ moisture content d) Consistency limits/ Atterberg Limits e) In-situ Density tests f) Tri-axial shear test for Effective Shear parameters (C’ and Φ’) with pore pressure measurements

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g) Permeability tests h) Soil classification Gradation analysis and incase of silt and clay soil Hydrometric analysis for fraction of the soil passing below 75 micron to 1 micron. Note. 1) 60 samples for each test (for items a to e and h and i 2) Only 5 samples be tested (for items f and g) E) Cement a) Specific gravity b) Specific surface area c) Consistency test d) Initial and final setting time e) Chemical analysis. f) Heat of Hydration g) Soundness test h) Compressive strength Note . One sample each from 3 different brands of cements F ) Road Works a) California Bearing Ratio (CBR) Note 1: California Bearing Ratio test shall be done on remolded soil samples compacted at OMC to standard proctor density. Three samples at each location should be collected for conducting unsaturated CBR test & three samples should be collected at each location for conducting saturated CBR test (four days saturation) and for a load penetration of 2.5mm, 5 mm, 7.5mm and 12.5mm may be given. Note 2. California Bearing Ratio test for soil sub grade on highway deviation road alignment @ 7 places along entire length 7kms @ the rate of three samples/each test/place/km length of road. For unsaturated CBR test=21 samples For saturated CBR test=21 samples

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Total samples to be collected and tested:-21+21=42 nos. Important Conclusion Notes: 1) All point for boring, test pits and sampling should be with the agreement of the Project Design Engineer 2) All test pits to be excavated for investigate the subsurface conditions to be a depth of about 4 m. with the agreement of the Project Design Engineer

3) Rotary core drilling should be undertaken to obtain relatively undisturbed samples of soil and rock to depths of at less More than 15 m below ground surface and to conduct packer permeability tests to these depths along the dam center line. Distance between neighbored boreholes should be agreed with the design engineer of PDA

4) Water pressure testing should be carried out within the boreholes along the dam centerline to assess the permeability of the foundation materials. Special provision will made in the drilling contract for water pressure (Lugeon) testing in weathered rock conditions where conventional packers cannot be used. In clayey materials, the packer should be seated within a tight-fitted (drilled-in) casing, while in sandy / gravelly material, pre-grouting and re-drilling of the packer section was conducted. In this way, packer tests could be conducted from 1.5 m depth. Samples comprising highly to moderately weathered granitic rock from boreholes in the quarry should be taken for laboratory tests to determine their properties with respect to their use as soft rock fill.

5) Geological cross-section along the longitudinal axes of the dam and spillway by a countable expression of the dimensions of rock layers must be clearly represented

6) Gravity tests of water conductivity for all boreholes along the dam axis should be provided in explanatory report and relevant drawings.

7) The testing agency /Laboratory shall have necessary equipment, trained technicians and other materials required for boring and testing. 8) At the time of submission of the quotation for this work the testing agency should submit its profile indicating the type of testing done elsewhere for any Multipurpose Project and the testing equipment’s viz type and numbers available with them.

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9) Once the testing work is awarded the testing agency should depute their technicians to the site for collection of the samples and to coordinate with the contracting agency who will make ready the borrow pits /trail pits or other materials viz cement, aggregates and sand etc. for taking the samples. 10) The quantity of the sample required for the total tests under each category of testing materials shall be intimated to the contracting agency by the testing agency. The testing agency should collect the samples carefully and where ever wax sealing is required for maintaining the field moisture content in case of undisturbed soil samples it should be done by the testing agency only and hand over the sample for smooth transportation to the contracting agency. 11) The testing agency should take sufficient number of core samplers and tube samplers along with them for collection of samples from in-situ trail pits. 12) The contracting agency i.e. Project Design Agency, shall make arrangements for the excavation of trial pits and borrow pits and provide labor and materials for collection of the samples at the site during sampling and transportation of the samples to the testing laboratory. 13) It is the testing agency’s responsibility that the correct types of samples are to be taken for testing. In this regard they should advice the contracting agency the manner in which the testing materials should be made ready for taking samples. 14) The time period given for testing and submission of the results shall be 2 calendar months from the date of work order. 15) Certain tests indicated above will take more number of days for preparation of test specimen for testing and saturation of samples etc. The testing agency should advise the contracting agency giving priority wise collection of samples for specific tests such that total time given for testing shall not extend under any circumstances. 16) The design earthquake for the high hazard potential dams other than the flood control dams is the maximum credible earthquake or an earthquake with a 1000-year return frequency.

17) For any clarification in respect of this work the testing agency should contact the under signed at the following address during office hours : Page 7

Contractor Agency:

Project Design Agency

Address:

Kabul, Afghanistan.

E-mail.

[email protected]

Please submit your quotation to the above email before May 10, 2018.

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