The design and selection of a particular type of foundation is a work of the RCC consultant The construction person must know the background so that the interaction with the designer is easy. Read this article so that you know the basics.
Overview:
In this series we are looking at the various stages in the construction of a building.
So far we have covered from land acquisition up to mobilization and from mass excavation up to columns of the first floor.
This article brings you the intricacies and steps in casting the roof slab.
For the purpose of clarity, the tasks have been grouped under:
A. Pre-concreting care: B. During concreting care: C. Post -concreting care:
All the Activities ,however, have been sequenced in a continuous serial nos from 1 to 47.
The activities sequence:
A.Pre-concreting care:
Columns:
1.Columns up to beam bottom
2.Curing of columns
3.marking of beam bottom on columns
4.fixing of runner blocks on columns
Beam bottoms & sides:
5.Fixing of beam bottom
6.Supports below beam bottom
7.Inside face of beam: side fixing
Slab centering:
8.Slab centering in plates
9.Gaps fixing with planks & closing of gaps qith iron strips or masking tape.
10.Fixing of Accrow spans
11.Levelling of centering plates
12.Keeping camber in the slab
Reinforcement laying:
13.laying of beam reinf.
14.Laying of slab reinf.
15.placing chairs below bent up bars
Electrical conduits/ fixtures:
16.Laying electrical conduits/ fan hooks/ down pipes from beams
Sunk portion:
17.Keeping pipe sleeve in the sunk portion for drainage pipe
Securing:
18.Placing cover blocks for beams & slabs
19. Fixing clamps for beams
20.Fixing tie bars in sleeves for deep beams
Joint inspection:
21.Steel measurement and checking
( jointly with clients engineer)
22.Laps counting
23.Extra bars counting
Arrangement for casting:
24.Installing the concrete pump
25.Fixing the pipes for concrete
26.scheduling the transit mixer ( TM)
27.Final checking by consultant
28.pour card approval
B. Care during concreting :
29.Placing concrete
30.Compaction by needle vibrator
31.levelling
32.slab thickness verification
33.finishing
34.Removing excess debris from slab
C.Post concreting care:
35.casting of specimen cubes
36.providing mortar bunds for curing
37.ponding with water
38.striking off beam sides
39. striking off slab centering
40. striking off beam bottom
41.Hacking the concrete surface
42.Sunk portions cleaning
43.waterproofing
44.ponding with water
45.Testing of cubes on 7th & 28th days
46.Reconciliation of materials
47.Bills
Construction starts with a dream of the builder and gets completed when the final cheque from the last customer is realized In this article we are going to review various decisions one has to take before the actual construction starts.
1.Lonecrusader?
The first decision which a builder needs to take is whether he shall be working alone on this project or needs a financier with him.
This has a few situations ;
1.Working with own funds
2.Having a working partner with him who shall also do part of the investment.
3.Having a sleeping partner [ financier] who shall not be operationally active.
4.To take loan from financial institutions.
Each decision has its own merits & demerits.
2.Ownland ?
Having decided mode of finance , the next decision is whethertoconstructthebuildingonownplotoritcanbedevelopedwithsomeoneelse’sland.
There are various practices followed.
For example,one such arrangement is called 60:40 method.
Here the builder does not do any investment in plot but has to bearentireconstructioncost. Outofthefinalpropertydeveloped, hehastoallot 40% ofthetotalbuilt uptothelandlord. Land lord may either do the marketing of this 40% property himself or through the builder .
Sometimes the builder may agree to pay the cash equivalentof 40% ofthepropertytothelandlordatthe prevailing marketrate.
3.Taketherightpeopleto plan :
Third decision is the appointment of Architect
The architect is appointed usually through previous association or references obtained within group.
For some , this selection is very simple, an architect who can give maximum yield on the given plot is considered eligible.
( Maximumbuilt upareapersqft. ofland)
Some builders consider the overall planning, uniqueness of design etc vital attributes in architect’s selection. And of course the crucial criterion is the professional charges of the architect.
4.PackagedealincludesRCCdesigns?
Another decision is whether to appoint RCC consultant separately ?
Various options exist: 1. Architect himself is also the RCC designer. 2. Architect has a RCC designer working with him or for him . 3. Architect recommends a RCC designer. 4. Architect leaves the selection of RCC designer to the builder.
In the cases 1,2 & 3 builder has a one point dealing with the architect who gets all RCC drawings done from his consultant.
5.Whowillgettheapprovals?
This is regarding the permission to build [ municipality approvals] to be obtained from the competent authorities, prior to beginning the construction.
The options are :
1. Architect shall himself liaise with the authorities and shall get the corporation approvals. 2. Architect shall only give the drawings. The builder needs to liaise with the authorities to get the corporation approvals.
3. Builder appoints a Liaison Architect who just gets permissions & approvals.
6.WhoshallfightforyouinCourt of Law ?
This decision is related to the appointment of the Legal consultant who shall guide the builder through any legal disputes arising anytime during the acquisition of land up to handing over of the property to the customers and even beyond.
7.The Supervision :
This decision is related to how the construction is going to be supervised for Quality ,Quantity and delivery ?
There are several options :
1.Builder deploys his own employees for supervision.
2.Builder appoints PMC [ project Management consultant ] for supervision.
3. An experienced engineer is given the contract of entire supervision on % basis.
Summary :
The real success of the construction project ,like every other venture depends upon the formation of an effective team.
It is prudential to spend enough time and diligence to hand pick the team members.