field study of rcc structures

FIELD STUDY OF RCC CONSTRUCTION PROJECT

SANJIB DAS (CIB11019)MANJEET YADAV (CIB11040)

Introduction

CONSTRUCTION OF RCC STRUCTURE

IMPLEMENTATION OF

IS 13920:1993

INTRODUCTION

FOUNDATION

It is the earth that provides the ultimate supporting for the structure.

TYPE OF FOUNDATION SHALLOW FOUNDATION

if Df/B ≤ 1

DEEP FOUNDATION

with Df/B greater than 1 but less than 15, are moderately deep.

Deep foundations such as pile foundations have Df/B ratio greater than 15.

SOIL TESTINGIt is the scientific method to determine the following properties:Bearing capacity of soil testPermeability testWater absorption testCore cutterBulking of sand

  SPT (Standard Penetration Test)

The standard penetration test (SPT) is an in-situ dynamic penetration test designed to provide information on the geotechnical engineering properties of soil.

PILING

It is a type of deep foundation distinguished from shallow foundations by the depth they are embedded into the ground.

It is necessary where the soil i.e, the base of the construction site is poor where the actual construction is to done. Otherwise we can directly go for the footing of the basement

SUPER STRUCTURE It is generally the portion of the building located above ground, in contrast with the basement and substructure underground.

Designing superstructures requires considering the pressure and force they will exert on the finished construction and balancing this to address concerns about safety and stability.

The size of the superstructure is an important factor in base design, as the base of the structure must be able to support the entire laden weight

REINFORCEMENT

Steel is used as the reinforcing material in concrete to make it good in tension. \

steel bars up to 12 mm in diameter are designated as bars while bars more than 12 mm in diameter are termed as rods.

The four types of steel used in concrete structures as specified in cl. 5.6 of IS 456 are given below:

(i) Mild steel and medium tensile steel bars conforming to IS 432 (Part 1)  

(ii) High yield strength deformed (HYSD) steel bars conforming to IS 1786  

(iii) Hard-drawn steel wire fabric conforming to IS 1566

(iv) Structural steel conforming to Grade A of IS 2062.  

FIELD SAMPLEIS 13920 RECOMENDATION

IGNORANCE IN FIELD

Both end should be bent at an angle of 135° but in this sample only one end is at 135°

Lap joint is absent in this sample which violates IS code

The gap between the bars is less than 25 mm between the middle longitudinal bar.

Stirrup bent is not done nor welded

CONCRETE Concrete consists of a rationally chosen mixture of

binding material such as lime or cement, well graded fine and coarse aggregates, water and admixtures (to produce concrete with special properties).

The stages of concrete production are:1. Batching or measurement of materials2. Mixing3. Transporting4. Placing5. Compacting6. Curing7. Finishing

IN FIELD IS 456 RECOMENDATION

COMPARISION

Mixing time of concrete in tilt mixer was about 30- 40 seconds

Mix design ratio was 1:1.62:2.97. The weighing box used to obtain this ratio was same for sand and gravels.

It should be atleast 2 minute

Separate weighing box should be used for batching of sand and gravels.

Hand made weighing box is used which Disturb the desired mix ratio.

MORTAR AND BRICK WORK

Mortar is a workable paste used to bind construction blocks together and fill the gaps between them. The blocks may be stone, brick, cinder blocks, etc.

Brick should be soak in water for 1.5- 2 hour before using it with mortar. But in this project the bricks were hardly soak in water for 10-20 minutes as a result brick will absorb water from mortar reducing the bond strength between mortar and bricks.

CONCLUSION

Due to lack of awareness of IS code and time, IS Code is not always followed

THANK YOU