Goa

1CASE HISTORY

R di l M f P t ti Remedial Measures for Protection of Cabo Hill Slopes,f p ,

At Rajbhavan, Goa

ITD Cementation India Limited

2Lit t R iLiterature Review

Raj Bhavan:

Official Residence Of The Governor, Goa Situated on top of Cabo Hill Promontoryp y 400 + Years old Elevation +40m From Mean Sea Level


3d f di l Need for Remedial Measures

Serious Threat To Raj Bhavan C k i P t Cracks in Pavements Cracks in Verandah C k i W Sl Cracks in Western Slopes Cracks on Slope Protection Structure Cracks on the Sea Wall Cracks on Parapet Wall


4ITD Cementation India LimitedCracks on Slope Protection

5ITD Cementation India LimitedCollapse of Hill Slope

6ITD Cementation India LimitedCollapse of Cladding Wall

7Causes for Instability of Slopes

60m thick, soft and incompetent soil strata on slope lying between two competent p y g pmedia - Laterite and Fresh Bed Rock

Higher Natural Slopesg p Toe Erosion by Tidal Waves Increased Structural Load Increased Structural Load Improper Drainage


8 Al d id dMeasures Already Provided Cladding wall with Buttress Cladding wall with Buttress Vertical Piles with Capping Beam Sea wall on toe Part Sea wall on toe Part Main Catch Water Drain Contour Drain Contour Drain Weep Holes Armour Blocks Armour Blocks Micro Piling, Grouting & S ling f Cr k


Sealing of Cracks

9l f d lDetails of Remedial Measures

Upper Part of Slope Prestressed Cable Anchors Prestressed Cable Anchors Intermediate Shear Interceptors at foot of Steep

Slope Inclined Bored Pilesp Shifting of Sewerage/Septic Tanks Sealing of Ground Cracksg


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l f d lDetails of Remedial Measures

Middle Slope Easening of Slope and Surface Drains Intermediate Shear Interceptors

V i l B d PilVertical Bored Piles Vertical Sand Piles T fi & T G d i Turfing & Terrace Gardening


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l f d lDetails of Remedial Measures

Toe Part of Slope Construction of Retaining Wallg Effective Shore Protection Works


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i iLong Term Monitoring

Slope Movement Monitoringp g Settlement Observations Pore Water Pressure Measurement Pore Water Pressure Measurement Monitoring of Ground Cracks


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M j A ti iti @ R j BhMajor Activities @ Raj Bhavan

Installation Of Cable Anchors Inclined Micro Piles Vertical Micro Piles Vertical Micro Piles Consolidation Grouting I t t ti Instrumentation


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1 S f L li 1. Surface Leveling

Clearing Leveling & Benching Working Platforms for: Installation of Cable Anchors Drilling of Inclined Piles Other Mandatory Tests


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2 C bl A h2. Cable Anchors

Providing in 4 Rows @ 2m c/c Staggered Vertically at an Average Depth of 16 25m @ Vertically at an Average Depth of 16.25m @ 4m c/c Staggered Horizontally or Until arrival of Hard Strata by Percussive Drillingy g

At An Angle of 20 wrt to Horizontal Providing and Installation of Cable Anchors Providing and Installation of Cable Anchors Stressing the Cable Anchors to 20-30 MT


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4 R f C bl A h @ 2 / ITD Cementation India Limited

4 Rows of Cable Anchors @ 2m c/c staggered vertically

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ITD Cementation India LimitedDrilling at an angle of 200 to Horizontal

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D illi Ri i O ti f 4th R f ITD Cementation India Limited

Drilling Rig in Operation for 4th Row of Cable Anchor

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D illi Ri i O ti t i ITD Cementation India Limited

Drilling Rig in Operation at various levels with view of Rajbhavan on Hilltop

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3 G ti C bl A h3. Grouting Cable Anchors k h b l d l Taking the Permeability Test Immediately

After Drilling Grouting the Anchor Hole with Cement in

Various Proportions. Redrilling the Same after Grouting Again Tested for Permeability Above Procedure Repeated Until arrival of

anticipated Lugeon value.


p g

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ITD Cementation India Limited Grouting

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4 35 D illi4. 35mm Drilling

D illi i 4 St i 0 75 1 5 3 0 & Drilling in 4 Stages in 0.75m, 1.5m, 3.0m & 4.5m

D illi i St d M @ 1 / Drilling in a Staggered Manner @ 1m c/c


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ITD Cementation India Limited Drilling

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ITD Cementation India Limited Drilling

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5 C lid ti G ti5. Consolidation Grouting

Cement Grouting in Various Proportions Grouting in Ascending Stage until Built up of Grouting in Ascending Stage until Built up of

Pressure Grouting Suspended if Pressure does not Grouting Suspended if Pressure does not

Develop and continued the same on the next Succeeding Day until Development of PressureSucceeding Day until Development of Pressure


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ITD Cementation India LimitedGrouting of Fixed Length

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6 RCC A h P d & G id6. RCC Anchor Pads & Grid

Design and Construction of RCC Reaction Blocks, Columns, Beams & Base Beam with M30 G d R d Mi C tM30 Grade Ready Mix Concrete


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ITD Cementation India LimitedRCC Anchor Pads & Grid Construction

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ITD Cementation India LimitedConstructed RCC Anchor Pads & Grid

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14 W H l14. Weep Holes

Drilling of Deep weep Holes of 10.00m Depth in Between Cable Anchors to Dissipate Pore pPressure

At an Inclination of 15 to Horizontal At an Inclination of 15 to Horizontal Providing Graded Filters of Coarse Sand and

Geo-MembraneGeo Membrane Providing of 90mm Dia PVC Perforated Pipe


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15 Sl M t M it i15. Slope Movement Monitoring

Provision Installation & Commissioning of Provision, Installation & Commissioning of Inclinometer of Standard Specification

To Be Provided at a Depth of 25m @ R L To Be Provided at a Depth of 25m @ R.L +20m, +30m & +40m 3 Nos at Each Level


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16 S ttl t Ob ti16. Settlement Observation

Providing, Installation & Commissioning of S ttl t G f St d d S ifi tiSettlement Gauge of Standard Specification

Providing 1mx1mx1m Concrete Blocks of M25 G d C tM25 Grade Concrete

Above Mentioned To be Provided @ R.L 20 30 &40 3 N E h L l+20m,30m&40m 3 Nos at Each Level


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17 C k M it i17. Crack Monitoring

Providing Installation & Commissioning of Providing, Installation & Commissioning of Crack Recorder of Standard Specification

Above Mentioned To be Provided @ R L Above Mentioned To be Provided @ R.L +20m,30m&40m 3 Nos at Each Level


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