FLOW CHART :PRE & POST ACTIVITIES IN CONCRETE
WORKABILITY SLUMP TEST PROCEDURE DURING BATCHING OF CONCRETE
CUBE CASTING PROCEDURE AND ITS CURING METHOD
CHECKLIST BEFORE AND AFTER CONCRETING
CONCRETE JOINTS TO BE FOLLOWED BASED ON SITE CONDITIONS
CONCRETE JOINTS TO BE FOLLOWED BASED ON SITE CONDITIONS
CONCRETE JOINTS TO BE FOLLOWED BASED ON SITE CONDITIONS
NOTE : The pictures discussed in slides are actually cold joints. The formation of cold joints maximum to be avoided in site. In case of cold joint due to non availability of resources or other external factors, discussed factors need to be practised. The actual Construction joint discussed in next slide.
CONSTRUCTION JOINT
Construction joints are provided to relieve the structure from Tensile stresses and formation of cracking since concrete is weak in tension and changes due to thermal effects.
VIBRATION OF CONCRETE The objective in vibrating concrete is to mobilise it sufficiently, so that it become plastic enough to enable air voids to be removed and the aggregate particles to gravitate together to form a homogenous mass. The stiffer the mix and the larger the aggregate particles sizes, the greater will be the force required to energize the mix. Vibration of Concrete is vital to achieve : 1. Maximum strength of the placed concrete 2. Maximum durability
3. Adequate bond and protection for reinforcement in the concrete
4. Avoidance of reduction of visual blemishes, such as honeycombing and blowholes on the surface of form cast concrete.
Factors influencing the Vibration of Concrete : 1. Physical properties of concrete based on their mixed proportions 2. Types of vibrators and vibration patterns
3. Techniques in handling vibrators, in particular spacing and duration of vibration.
VIBRATION PROCEDURE
METHOD OF CURING
Pounding curing Spraying or Fogging
Sealing Compounds
Membrane Curing