Project : Approximate estimation of Rigid pavement

Item : Excavation in Hard Rock (by Blasting)

BySandeep Bora AP14003Anchit Agrawal AP14012Aditya Avinashe AP14079Pratik Dalai AP14081Shivali Kalra AP14088

Topics Approximate estimation of rigid pavement

Specifications of excavation in hard rock

Brief Specification

Detailed Specification

Rate Analysis for excavation in hard rock

Rigid pavement cost per kmSr No Project

Distance (km)

Cost (cr)Cost/km

(cr)

1 Mudhol Maharashtra border road on SH 18 in Karnataka 107.94 317.60 2.94

Contractor- Ashoka Buildcon and GVR Infra (On going project)

2 Malavalli to Pavagada(karnataka) 193.34 313.65 1.62

Contractor- Sadbhav Engineering Ltd and GKC Projects Ltd

(On going project)

3 Trichy Karur road(4 lane road) 63.00 732.84 2.91

Contractor-Reliance Infra (completed project)

4 Construction of approach road from South Garo Hills to Jetra 17.00 28.76 1.69

(On going project)

5 Construction of road from Pakoti to Kamsha 6.50 9.50 1.46

(On going project)

AVERAGE cost per km 2.13

Brief specification

Excavation for foundation in hard rock by blasting including trimming and levellingthe bed and removing the excavated material and stacking it into measurable heaps within a distance of 50 meters from site area.

Lift: 0 to 1.5m

Detailed specification Scope and objectives

Equipment used

Material Used

Workmanship

Testing and Acceptance Criteria

Mode of measurement and payment

Scope and Objectives The purpose of this procedure is to establish the methodology to be followed

for excavation work during the construction phase .

This procedure is applicable to the execution team. It intends to co-relate and control the entire task needed to be done in order to achieve satisfactory construction excavation work.

Excavation is to be done for Hard rock by the means of blasting.

We have used a machine intensive approach .

Scope of work- 10 cubic meter

Equipment deployed Hydraulic Excavator

Tipper

Jack hammer

Hydraulic excavatorExcavator(Hyundai 250 R)Purpose:

Digging of trenches ,holes and foundation.

Material handling,

Pising,

Demolition

Attachment:

Bucket, Breaker,

Auger

Rent

Rs 2200/hr

Capacity:

Bucket size: 0.93 cum

TipperTipper (Bharat Benz)Purpose:

Hauling of material

Charges

Monthly rent (1.25 lakhs excluding diesel)

Capacity: 14 cum

Jack HammerJack hammerPurpose:

Drilling of holes,

Depth of drilling is 2m in this case

Action of drilling takes place by percussion action.

A pilot rod is drilled into the surface with the help of jackhammer

Charges: Rs11/ft or Rs 400/hour

Material Used Explosives

Special Gelatine (gelatine stick)

Powergel IDL

25 mm thick

Rs 2000/25kg

Each stick of 125 grams.

Electric detonator SED – Rajasthan Explosives

1.8 m long wire

Rs 12 / Piece

Workmanship Preparation of surface:o Firstly the ground for blasting should be cleared of all obstacles.o The ground should be preferably leveled.o The ground should be cleaned and marked.

Method of Blasting:o Holes are to be drilled in triangular pattern for the required length.o The electronic detonator is inserted into the explosive gel tube which is connected to

the external wire circuito Explosives are placed within the hole and are then grouted with dry soil up to the topo The connection are checked and rechecked by the blastero All the explosives are connected in parallel and series connectiono This wire is connected to the detonating fuse.o warning siren are sounded at an interval of 5 minutes before blasting, all the traffic in

the area should also be halted & red flags to be placed along the way, fragile structureshould be covered by polymer or plastic sheets to avoid damage.

o The blast shed should be located at least 10 m from the blasting area.o After the detonation has taken place the area is excavated with the help of a excavator &

loaded into the tipper.o Small pieces of rocks are removed and ground is levelled.

Blasting pattern

Testing and Acceptance Criteria The dimensions of the pits will be checked as per the GFC drawings .

All over excavations filled back to required lines, levels and grades by placing plain cement concrete of grade M10 and/or richer and/or by compacted earth, as directed by the Engineer, at the Contractor’s cost.

Sand replacement method of testing the field density on site to ensure the desire densification has been obtained i.e minimum 95% of its maximum dry density.

Mode of measurement and payment Mode of measurement-

As per IS 1200(Part 1),

o Mode of measurement for Excavation is in cubic meter

o Each dimension shall be measured to the nearest 0.01m

o Areas shall be worked out to the nearest 0.01 sq.m

o Cubical content shall be worked out to the nearest 0.01 cu.m

o Working Authorised working space shall be special in each case. Where authorised working space is not so specified the following shall apply:

600 mm measured from the face of substructure ( including protective measures, if any) at lowest level, where extra working space is required.

Mode of payment-

o Payment shall be done as per the GFC drawings.

Rate analysis Rate as per calculations: Rs 680.58

Rate as per DSR 2014: Rs 653

Rate analysis