Letter on Boulder Apron and Stone Pitching works

Written by Team Highway Correspondence

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Letter on Boulder Apron and Stone Pitching works

Content brief:

  • Letter on Apron and Stone Pitching works:The following content pertains to the highway project structure slope, up and sownstrem floor protection construction works.
  • It contain a independent engineer’s findings of defective works of Boulder Apron and Stone Pitching works at CD structures on project highway.
  • This article includes a various sample site instruction notices or letters to the concessionaire by the IE.
  • It reference to defects identified in structure construction during site inspection by independent engineer team.
  • These site instructions are in a fashion of summarizes the identified defect vis-a vis to Technical specifications. And, prescribing remedial measures along with a time frame for corrective actions by an independent engineer.
  • The following are the various sample site instruction letters on structure construction works

Letter on Boulder Apron and Stone Pitching works

Site instruction letters on Unsatisfactory Boulder Apron and Stone Pitching works for CD Works

To

The Concessionaire

Subject: Unsatisfactory Boulder Apron and Stone Pitching works for CD Works

Ref: Technical Specification Clause No 2503 & 2504 of MORT&H.

Dear Sir,

With reference to our site staff visits at site, we noticed that the Boulder Apron and Stone Pitching works for CD works were not executed as per Clause 2503 & 2504 of MORT&H Specifications.

The size of stone is not meeting the specifications as per clause 5.3.7.2 of IRC: 89. As per clause 2503 of MORT&H Specifications, the stones used in Apron/Stone Pitching shall be sound, hard, durable and fairly regular in shape. Stone subject to marked deterioration by water or weather shall not be used. Further you have not submitted the filter media design for Stone Pitching works as per clause 2504 of MORT&H Specifications.

This is for your information and compliance.

Thanking you.

Letter on Boulder Apron and Stone Pitching works Technical specifications as per MoRT&H

Clause 2503 & 2504 of MORT&H stated as follows

Boulder Apron

The size of stone shall conform to Clause 5.3.7.2 of IRC: 89.

The size of stone shall be as large as possible and no stone shall weigh less than 40 kg.

The specific gravity of stones shall be as high as possible and not less than 2.4.

To ensure regular and orderly disposition of the full intended quantity of stone in the apron, template cross walls in dry masonry shall be built about a metre thick and to the full height of the specified thickness of the apron, at intervals of 30 metres all along the length and width of the apron. Within these walls, the stone shall be hand packed.

The surface on which the apron is to be laid shall be levelled and prepared for the length and width, as shown on the drawings.

In case the surface is below the low water level, the ground level may be raised upto low water level by dumping earth and the apron laid thereon.

In such cases, the quantity of stone required in apron shall be re-worked by taking the toe of pitching at higher level.

Filter Medium

The material for the filter shall consist of coarse sand, gravel or stone.

One or more layers of graded materials, to act as a filter medium, shall be provided underneath the pitching, to prevent loss of the embankment material and build up of uplift head on the pitching.

The gradation of the filter material shall satisfy the following requirements:

D 15 (Filter)

———————— < 5

D 85 (Base)

 

 

D 15 (Filter)

4 < ——————— < 20

D 15 (Base)

 

 

D 50 (Filter)

———————— < 25

D 50 (Base)

A Note to the Visitor on the Site instruction Letter on Boulder Apron and Stone Pitching works

It is that a few important and mandatory aspects are only discussed herewith. Kindly note that the above inspection observations are considered examples. You may adopt the gist of the subject and change it to suit the current need. And before using this content in your letter drafting, you need to ensure the specific CA contractual conditions and other aspects, etc.

Also Read the Site Instruction letter on Hot mix plant operations

site Instruction on DBM work.

Site Instruction on earthen shoulder 

Site instruction letter on faulty highway works

You can find various sample draft formats for highway operation and maintenance.

Additionally, you can find various sample draft formats for highway construction.

FAQ’s Related to Letter on Boulder Apron and Stone Pitching works

The team’s highway correspondence will update relevant FAQs subject to request from the visitor/user.

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