Job work

The following Job Work required for Topographical survey and Soil investigation for Rrovision of deficient Married accommodation for sailors near Ashoka Park Visakhapatnam.

Topographical survey with 3m grid intervals and 0.5m contour intervals to provide with accurate base - line information data with all existing permanent infrastructure/ utilities details of the proposed site near Ashoka Park including reconnaissance to get broad view of entire area for planning [using Total station], TBM to be marked with paint on existing structure complete all as directed by Engineer-In-Charge. CAD file along with contours and benchmark, duly marked, must be submitted in a CD( 4 copies).

Mobilisation of equipment to site for detailed soil investigation and shifting them location to location of bore holes and for in situ tests.

Boring holes 150mm dia in any types of soil including weathered rock, SDR and soft rock but excluding hard rock/ fractured rock upto a depth untill hard rock/ fractured rock strata encountered including following activities: (a) Conduct of SPT at every 1.5 m interval or change of strata whichever occurs earlier. (b) Collection of undisturbed soil sample (UDS) at every 1.5 m interval or change of strata whichever occurs earlier (a minimum gap of 500mm shall be ensured between SPT and collection of UDS). Note : (i) Drilling in hard rock / fractured rock shall be measured and paid under item No 4. (ii) In case of meeting boulders, the boring beyond boulder depth shall be measured under this item. (iii) In case of non-feasibility of collection of undisturbed soil sample, disturbed soil sample shall be collected, duly recording the reason.

Drilling holes in hard rock/ fractured rock using hydraulic drilling machine within the bore hole for cutting cores in rock and collection of cores of requisite size and length as per relevant IS standards. Drilling shall continue till minimum 5m into hard rock strata.

(a) Conduct of following laboratory tests on rock samples/ cores collected from bore holes as per relevant indian standards (IS-2720 (all parts) and IS 1498, IS-9143, IS-13030, IS-9221,IS-8764,IS-9179, IS-10050, IS -10082, IS-10782, IS-12608, IS-13047, IS-3025) (i) Visual classification. (ii) Density. (iii) Specific gravity. (iv) Hardness. (v) Degree of weathering. (vi) Uniaxial compression test (both saturated and unsaturated). (vii) Point load strength index. (viii) RQD(rock quality designation) Note: (i) Item to be operated only in case of encountering rock in borehole with the written permission of GE. (ii) This is compulsory item for the cases where pile foundation is anticipated.

Conduct of following laboratory tests as per relevant indian standards [see IS 2720 (all parts) IS 1498 and IS 3025] on soil samples collected: (a) Test on disturbed/ undistubed samples :- (i) Visual and engineering classification. (ii) Sieve analysis and hydrometer analysis. (iii) Atterberg limits (liquid limit, plastic limit and shrinkage limit). (iv) Specific gravity. (v) Free swell index. (b) Test as on Undisturbed samples. (j) Bulk density and moisture content. (ii) Unconfined compression test (on remoulded undisturbed sample) (iii) Swelling Pressure (on undisturbed and remoulded sample) (iv) Determination of C&Ø valvues using direct shear (drained/undrained ) (on remounded or undisturbed sample) or triaxial compression tests (on undisturbed or remoulded samples) or vane shear test.

Chemical analysis of ground water sample collected at bottom of one bore hole.

Chemical analysis of soil samples one each from each strata in respect of one bore hole. If different strata (s) encountered in any other borehole additionals soils samples to be analysed. Note: Composition of subsurface Investigation report 1. General 1.1 On completion of the in-site and laboratory tests, subsurface investigation report shall be prepared which should include geological information, procedure adopted for investigation, field observations, laboratory or test data, analysis, interpretation, recommendations etc. 1.2 Information to be provided: The report shall include but not be limited to the following: (a) Dimensioned Plan showing location and depth of in-situ tests; the co-ordinates of bore hole locations with reference to prominent permanent features of the site duly signed by GE and Geo consultant; b) Geological information of the area; c) General topography of the site, duly marking RL of the location of bore holes with reference to RL of nearby permanent features available at site duly signed by GE and Geo Consultant; d) Past usage and historical data of the site, if available. Information regarding flooding of the site in the past, High flood level etc. e) Borelog and trial pit log duly signed by GE and Geo Consultant. f) In-situ test results; g) Plot of standard penetration test (N values both uncorrected and corrected) with depth for identified areas; h) Laboratory test results and i) Summary of strata profile. 1.2.1 Reporting of in-situ and laboratory test results should be in accordance with relevant Indian Standards. 1.3.1 Analysis and Interpretation of Results. The following shall be included in the report: a) Analysis of test results. b) Discussion and interpretation of results analyzed including basis of adopting design parameters for the substrata. c) For shallow foundations (i) Net allowable bearing pressure considering shear, settlement criteria as well as SPT value for isolated footing, continuous strip footing and raft foundation at depth 1.5 m, 2.0 m, 2.5 m and 3.00 m. For calculations IS: 6403 shall be used. (ii) Modulus of subgrade reaction and modulus of elasticity of substrata. (iii) In case of UG Sumps/ Swimming pools K value from 0.5m to 5.0m depth. (iv) Table showing the factors considered for calculation of SBC shall from part of the report. All references to relevant tables/ charts/ clauses of IS Code shall be mentioned : d) For pile foundations: Safe load carrying capacity (compression, pull out and horizontal with free head as well as supported head pile load capacities shall be worked out for 300,400,450 & 500 for under reamed piles and for 450, 500, 550, 600, 700 & 750 dia for end bearing piles. (i) A actual crushing strength (uniaxial compression test) of rock sample shall be used for calculation of pile capacity. (ii) A table showing the factors considered for calculation of pile capacity shall from part of the report. All references to relevant tables/ charts/ clauses of IS code shall be mentioned. (iii) The depth of fixity of pile shall be calculated and calculations shall be part of the report. (iv) Requirement of permanent liner including required depth ashall be mentioned . (v) The minimum socket depth at the end of pile shall be mentioned. e) If weak soil with lesser N value as specified in table-1 of IS 1893 (part-1) 2016 is encountered then evaluation of liquefaction potential shall be assessed and remedial actions to be adopted shall be specified. f) Suitability of the soil for backfilling around foundations/ filling under floors. g) Susceptibility of sub-soil strata to liquefaction, if any, in the event of dynamic loading and requisite remedial measures. h) Remedial measures against the presence of harmful chemicals in the sub-soil/ground water i) Remedial measures for foundation footings, plinth beams and filling under floors in case of meeting expansive soils. 2. The soil investigation report should be vetted by any IIT/NIT/ Andhra University.

CD Containing video evidence of depth of each bore hole & machinery deployed at site by kept in record. Note: All work shoud be carried out as driected by Engineer in Charge

P SRINIVASA RAO

Helios Engineering Consultants