MORTAR

• Binding material ( bond strength ) + fine aggregate ( rigidity, prevent shrinkage ) + water ( flexibility & plasticity ) 
• Ph of water - potable water - should not be less than 7 
• Water quality code - IS 456 

FINE AGGREGATE 
• Major component - Silica / oxides of silica 
• Major mineral component - quartz + feldspar 
• Fineness index used for mortar : 2.5 - 3 ( >2.5 , < 3 ) 

• Fineness index : relative size of fine aggregate to coarse aggregate

Aggregate type and Fineness index 
Fine  : 2.2 - 2.6
Medium   :  2.6 - 2.9
fine coarse  :  2.9 - 3.2 

CLASSIFICATION BASED ON ORIGIN 

PIT SAND  
• Collected form pit of depth 1 - 2 m 
• Red orange 
• Angular 
• High bond strength 
• Used in superior works 

RIVER SAND 
• Collected from river 
• White 
• Spherical, rounded 
• Low bond strength 
• Used in plastering works 

SEA SAND
• Collected from sea shore 
• Brownish yellow
• Round 
• Not used in any type of construction due to salt content

BULKING OF SAND 
• Expansion of sand due to contact with moisture 
• 18 - 38 % volume increase due to 5 - 6 % moisture content 
• Maximum bulking occurs at 5 %



LIGHT WEIGHT  MORTAR
• < 15 KN/m3 
• Only very fine particles included 

HEAVY WEIGHT MORTAR
• > 15 KN/m3 • Medium fine particles


SPECIAL TYPE OF MORTAR 

i. fire resistant mortar : aluminum cement + fire brick powder 
ii. Light weight mortar : lime + saw dust / pumice stone 
iii. Packing mortar : resists oil passage iv. Sound absorbing mortar : density : 6 - 12 KN/m3 v. X ray shielding mortar : density - 22 KN / m3

Comments

Post a Comment

Popular posts from this blog

UNITS OF MEASUREMENTS, PAINTING COEFFICIENT, OUT TURN, QUANTITY CALCULATION

Image
  DEDUCTION  • MASONRY : < 0.1 m2 - no deduction  • PLASTERING :  < 0.5 m2 - no deduction  0.5 - 3 m2 - one side deduction  > 3 - both side deduction  • End of beams, rafters, purlins < 0.05 m2 - no deduction  • Bearing of floors, roof slabs etc. - no deduction DIGREE OF ACCURACY  • Volume - 0.01 m3  • Area - 0.01 m2  • Dimension - 0.01 m  • Weight - 1kg  QUANTITY CALCULATION  PCC  • Maximum size of aggregate 40 mm  • For 1 m3 PCC - 0.95 m3 coarse aggregate is required  RCC  • Maximum size of aggregate 20 mm  • For 1m3 RCC - 0.90 m3 coarse aggregate is require  RCC For 1:1.5:3  Wt of cement = (1/3) x 0.90 x 1440 = 432 kg  Wt of sand = (1.5/3) x 0.90 x 1600 = 747 kg  PCC For 1:4:8  Wt of cement = (1/8) x 0.95 x 1440 = 171 kg  Wt of sand = (4/8) x 0.95 x 1660 = 760 kg PLASTERING  1:3 - 0.14 m3 / 10 m2 (sand) cement = (1/3) x 0.14 x 1440 = 67 kg  1:4 - 0.15 m3 / 10 m2 (sand) cement = (1/4) x 0.15 x 1440 = 54 kg  1:5 - 0.15 m3 / 10 m2 (sand) cement = (1/5) x 0.15 x 1440 = 43 kg
Read more

MACHINE TOOLS - SHAPER MACHINE

Image
The shaper is a machine tool used primarily for:  1. Producing a flat or plane surface which may be in a horizontal, a vertical or an angular plane.  2. Making slots, grooves and keyways  3. Producing contour of concave/convex or a combination of these Working Principle: The job is rigidly fixed on the machine table. The single point cutting tool held properly in the tool post is mounted on a reciprocating ram. The reciprocating motion of the ram is obtained by a quick return motion mechanism. As the ram reciprocates, the tool cuts the material during its forward stroke. During return, there is no cutting action and this stroke is called the idle stroke. The forward and return strokes constitute one operating cycle of the shaper.  Construction: The main parts of the Shaper machine is Base, Body (Pillar, Frame, Column), Cross rail, Ram and tool head (Tool Post, Tool Slide, Clamper Box Block). Base:  - The base is a heavy cast iron casting which is fixed to the shop floor.  - It supports
Read more

OPEN QUIZ RANKLIST 3

 1 56 / 63 HaRitHa 2 54 / 63 Sebin 3 53 / 63 Anuja sundareshan 4 53 / 63 Arun aravind 5 52 / 63 Faiz 6 51 / 63 aparna B 7 51 / 63 Veni 8 51 / 63 Anaswarakp 9 51 / 63 Akshay k 10 51 / 63 Minnu 11 50 / 63 Zehmat 12 50 / 63 Hima 13 49 / 63 Sreejith tk 14 48 / 63 AISHU 15 47 / 63 Prasee 16 47 / 63 Aswaniraj 17 46 / 63 Mumtaz 18 46 / 63 Ganga 19 45 / 63 Hannath N M 20 45 / 63 Arya... 21 44 / 63 Greesh 22 44 / 63 ANU M 23 43 / 63 Archana 24 43 / 63 Nirosha 25 43 / 63 CG 26 43 / 63 Nisham 27 43 / 63 Nikhil Murali 28 43 / 63 Suneesh 29 43 / 63 Aswathy 30 43 / 63 remya basanth 31 42 / 63 Haritha 32 41 / 63 Mohamed Hafeez 33 41 / 63 Aswati 34 41 / 63 salma  35 41 / 63 Akhila Ag 36 40 / 63 Gp 37 40 / 63 Aleena 38 40 / 63 Aami 39 40 / 63 Vrindha  40 39 / 63 Aiswaryasajeevan  41 38 / 63 Spread a smile 42 38 / 63 ashlin stanly 43 38
Read more