Treatment of dampness in walls in many ways

Dampness is the cause, reason and initiator of many defects and diseases in all sorts of construction from roads and transport systems to building and housing facilities. It might be a headache for you in rainy season and it might not let you sleep easily because of the danger and consequences of its presence. This post will let you know how to treat if your walls or building is being effected by dampness as well as will give you remedial measure that will ensure safety of your structure from all such devastating defects.

Dampness in walls

Before applying any remedial measure to a damp wall there should be free escape for any water that has already entered in the wall.

Silica Solution is transparent and very effective in resisting dampness.

Internal Treatment of walls 

Internal treatment of affected walls would consist of removing the old plaster, applying a slurry coat of neat cement with a water proofing compound and then cement rendering with a dense mortar, of 1:2 with integral water proofer added.

Another internal treatment for damp walls is the application of an impervious coating of some material or a coating of bitumen or tar followed by blinding with sand and plastering.

Preventing Dampness in walls

The following methods are also used for preventing dampness in walls

a) Two parts by weight of coal tar and one part by weight of pitch are put in a vessel, heated and stirred, until the mixture is sufficiently liquid. It is then applied on walls, and is found to keep out dampness very wall.
b) Spray or paint the walls with a solution of sodium silicate, followed by a solution of calcium chloride, which forms an insoluble silicate.

If dampness is confined to one position near ground floor level above the D.P.C., it may be due to a hole or crack in D.P.C. through which moisture can pass into the wall alone.
Dampness below ground level may be due to lack of sub-soil drainage, absence of vertical D.P.C.

Repelling Materials

Water repelling compounds are mixed in cement to make it water repellant, Examples are;
a) Chemically active ….. sodium and potassium soaps
b) Chemically inactive ….. calcium soaps and resin oils

What is Pile cut-off Level? Pile Foundation

Pile Cut-off level is the actual level at which the piles below pier are made to be of the same level. The concrete of pile is cut-off at the specified level (given in the specifications or drawings usually around 75 mm) while the steel is kept projected in-to the pile cap to make an effective bond between pile cap and piles.

What is Pile Cut-off Level

Why pile is trimmed or cut?

For Piles casted in dry bore holes while using temporary casing, piles heads shall be casted to a level a bit above the specified cut-off so that, after cutting or timming, a sound concrete connection can be made with the pile.

While we cast the piles under water we use tremie method of concreting. In this method the shaft of concrete pile is casted by using a tremie pipe which is lowered below the water level or the interfacing concrete and concrete is poured with pressure while the slurry and other raw concrete or weak concrete comes up. For tremie method slump mix should be greater than 175 mm.

Pile cut-off level can be above or below the group. When it is above ground, Concrete should overflow from the pile head on completion. Due to tremie method the upper part of pile consists of weak concrete as well as some contaminated boring debris.

In case the pile cut-off below the ground, the concrete level should be raised to allow for around 1 m for trimming off the weak concrete.

Traditionally the cropping or trimming process to achieve the required cut off level is done using a jackhammer or hand-arm vibration syndrome (HAVS).

Unable to Connect to Database Connection, Would you like to configure the database connection now? Primavera P6 [SOLVED]

During the Primavera running process or mostly due to computer crash due to power supply failure or any similar issue you got an error in Primavera P6 regarding connection to database PMDB, 

Reason

PMDB is Project Management Database that is connected via Microsoft SQL Server (PRIMAVERA). What happens due to computer or PC crash this service gets stopped and PM can’t run this service on its own and thus you have to run this service;

Unable to Connect to the database. Would you like to configure the database connection now? 

Solution

For that;

1) After getting the error “Unable to connect to the database. Would you like to configure the database connection now?” just hit “NO” click Cancel in the Login to Primavera Window and close the application;

2) Go to the location; 

C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Microsoft SQL Server 2005\Configuration Tools

Run SQL Server Configuration manager (Click to enlarge) 

3) And run the SQL Server Configuration Manager as shown;

SQL Server Configuration Manager (Click to Enlarge)

4) Select SQL 2005 Service from the left you will see SQL Server (Primavera) having red status symbol shown on the server showing the service is stopped, 

5) Right click the SQL Server (Primavera) and click Start the Service and wait for the service to get started.

Run the SQL Server (Primavera) (Click to Enlarge)

Run the Service and Your are done (Click to Enlarge)

6) Now run the Primavera and you are done,

If you have any further queries just contact us via admin@iamcivilengineer.com

Practical Civil Engineering Works Questions and Answers by Vincent T.H. CHU

Working in the field as a civil engineer is sometimes very challenging. The diversity in the conditions and nature of job from project to project varies. The extent of variation is such that even if you belongs to one major category like transportation engineering your every single project will have hundreds of unique happenings and hundreds of unique challenges.

In such a condition you will search on the internet as well as you will go and try to consult some experienced individuals who might have gone through some similar situation or might know the solution. How about a book that has hundreds of such solutions already been answered by world class level engineers and professionals working for decades in the field.

Download 200+ Questions and Answers on Practical Civil Engineering Works

Book Title

200 Questions and Answers on Practical Civil Engineering Works

Author

Vincent T. H. CHU

Contents of the Book

Bridge Works

Concrete Structures

Drainage Works

Earthworks

Piers and Marine Structures

Road works

Pumping Station

Reclamation

Water retaining structures and waterworks

Pipe jacking and Micro-tunneling

Piles and Foundation

General

About the Book

This  book  is  intended  primarily  to  arouse  the  interests  of  graduate  engineers,  assistant engineers and engineers in the technical aspect of civil engineering works. The content of the  book  mainly  focuses  on  providing  the  reasons  of  adoption  of  the  various  current practices  of  civil  engineering.  By  understanding  the  underlying  principles  of  engineering practices, graduate engineers/assistant engineers/engineers may develop an interest in civil engineering  works.  It  is  also  intended  that  the  book  will  serve  as  a  useful  source  of reference for practicing engineers.

Preview of the Book

Here is the live view of the book; 

Download the Book

To Download the book "200 Questions and Answers on Practical Civil Engineering Works" by Vincent T. H. CHU. just click any of the link below;

Download 200 Questions and Answers on Practical Civil Engineering Works by Vincent T.H. CHU

or

Download 200 Questions and Answers on Practical Civil Engineering Works by Vincent T.H. CHU

Disclaimer: The book /software shared here has not been uploaded and only link to download has been shared if you have any trouble with the link contact us at admin@iamcivilengineer.com

50+ Civil Engineering Materials MCQs

Civil Engineering Materials includes the introduction as well as detailed characteristics of various structural and construction materials used throughout the world, like timber, steel, concrete, bricks, cement etc. Here are 50+ multiple choice questions (mcqs) related to civil engineering Materials

1. ___________________is obtained by distillation of bituminous shales.

a. Coal tar
b. Mineral tar
c. Wood tar
d. Road tar
e. Crude coal tar

2. _________________is prepared entirely from crude tar as a byproduct of high temperature carbonization of coal in coke ovens or in retorts.

a. Road tar
b. Mineral tar
c. Coal tar pitch
d. Bitumen
e. Crude coal tar

3. Test performed to measure the grade of bitumen is known as____________

a. Penetration test
b. Fire point
c. Flash point
d. Melting point
e. Boiling Point

4. __________________is the lowest temperature at which the vapour of a substance can be ignited in air by a flame under specified conditions of tests.

a. Fire point
b. Melting Point
c. Flash Point
d. Boiling Point
e. Freezing Point

5. ______________asphalt containing finely divided mineral matter passing 75 micro meter (sieve No. 200)

a. Mineral filled asphalt
b. Emulsified asphalt
c. Asphalt Joint fillers
d. Asphalt cut back
e. Asphalt cement

6. Minimum viscosity range specified for asphalt cement is_____________

a. 135 C
b. 120 C
c. 100
d. 75
e. 150

7. The standard temp for penetration test Is________________

a. 75 C
b. 25 C
c. 100 C
d. 120 C
e. 130 C

8. For thin film oven test the temp___________is maintained for 5 hours.

a. 150 C
b. 100 C
c. 163 C
d. 25 C
e. 75 C

9. _______________is a mixture of asphalt and fine mineral material in such proportions that it may be poured hot or cold into place and compacted by troweling to a smooth surface.

a. Asphalt mastic
b. Asphalt overlay
c. Asphalt macadam
d. Asphalt leveling course
e. Asphalt well graded

10. The solubility test is measure of the ______of asphalt cement

a. Purity
b. Impurity
c. Saturation
d. Unsaturation
e. Dissolution

11. Mortar is a mixture of

a. Fine aggregate, stone and water
b. Binding material, silt and water
c. Fine aggregate binding material and water
d. Coarse aggregate binding material and water

12. In case of lime mortar, the ratio of lime and sand is;

a. 2:1
b. 2:2
c. 1:3
d. 4:1

13. For internal plastering ratio of cement and sand should be;

a. 1:8
b. 1:5
c. 4:3
d. 3:6

14. For general use lime sand mortar should be in the ratio of;

a. 1:3
b. 1:6
c. 2:4
d. 1:5

15. Dotting in front face of stone masonry is known as;

a. Grouting
b. Pointing
c. Guniting
d. Shortcreting

16. Fissures and cracks are filled by a material known as;

a. Lime mortar
b. Grout
c. Sand cement mortar
d. Cement mortar

17. In case of lime mortar masonry, maximum height should not be more than

a. 3m high
b. 2m high
c. 1.5 m high
d. 2.5 m high

18. In case of hydraulic lime maximum time should be;

a. 4 hours
b. 2 hours
c. 6 hours
d. 24 hours

19. In case of lime mortar for masonry works ratio of cement and sand is;

a. 1:5
b. 2:1
c. 1:6
d. 1:3

20. After construction cement mortar should be curd

a. 10 days
b. 20 days
c. 5 days
d. 15 days

21. Limestone containing about 30% of alumina and silica is called;

a. Kankar
b. Granular limestone
c. Magnesia
d. Lime milk

22. Quick lime is;

a. Carbonate of lime
b. Oxide of calcium
c. Product left immediately after calcinations of pure limestone
d. Lime quickly treated with water
e. Granular lime

23. Lime consists entirely of calcium oxide is called;

a. Poor lime
b. Rich lime
c. Hydraulic lime
d. Lime stone
e. Eminent hydraulic lime

24. Lime contains more than 10% of clay impurities in form of silica, alumina and iron oxides.

a. Poor lime
b. Hydraulic lime
c. Rich lime
d. Kankar

25. For under water work, commonly used lime is

a. Fast lime
b. Lean lime
c. Rich lime
d. Eminently hydraulic lime

26. Commonly used lime in white washing is;

a. Quick lime
b. Lean lime
c. Fat lime
d. Hydraulic lime
e. Rich lime

27. White lime contains;

a. Ferrous
b. Calcium oxide
c. Silicon oxide
d. Magnesium oxide
e. Aluminmum oxide

28. A thin pourable suspension of slaked limein water;

a. Milk of lime
b. Hydrated lime
c. Eminently hydraulic lime
d. Moderately hydraulic lime
e. Feebly hydraulic lime

29. Ferrous alloys have chief constituent

a. Chromium
b. Nickel
c. Iron
d. Tungsten
e. Vanadium

30. Specific gravity of mild steel is

a. 6.8
b. 7
c. 7.5
d. 7.8

31. High carbon steel has structure

a. Granular
b. Feeble
c. Tough
d. Fine
e. Deshaped

32. Which is the crudest from of iron

a. Pig iron
b. Cast iron
c. Wrought iron
d. Mild steel
e. Stainless steel

33. Which is not the property of pig iron

a. Brittle
b. Difficult to bend
c. Non-ductile
d. Magnetized
e. Non-welded

34. Carbon contents in cast iron range from

a. 2-3
b. 2.5-4
c. 2-4.5
d. 2.5-5
e. More than 5

35. Which is the purest form of iron

a. Pig iron
b. Cast iron
c. Wrought iron
d. Steel
e. Carbon steel

36. Which steel is used in making tools like drill, chisels, cutlery

a. High carbon steel
b. High tension steel
c. Medium carbon steell,
d. Normal carbon steel
e. Mild steel

37. For a material to be classified as steel, there should be no

a. Free graphite
b. Free coal
c. Charcoal
d. Alumina
e. Silica

38. Steel with carbon content from 0.3 to 0.8% is

a. Medium carbon steel
b. Normal carbon steel
c. Carbon tool steel
d. Alloy steel
e. Mild steel

39. Le chatelier apparatus is used to perform

a. Fineness test
b. Soundness test
c. Consistency test
d. Compressive strength tests

40. The maximum particle size of fine aggregate is

a. 2.5 mm
b. 4.75 mm
c. 5.85 mm
d. 6.5 mm

41. The workability of concrete by slump test is expressed as;

a. Minutes
b. Mm/h
c. Mm2/h
d. Mm

42. A good quality cement should have higher percentage of

a. Silica
b. Free lime
c. Di-calcium silicate
d. Tri-calcium silicate

43. The maximum water-cement ratio for durable concrete is;

a. 0.2
b. 0.4
c. 0.6
d. 0.8

44. Which of the following cement is expected to have the highest compressive strength after three days?

a. Ordinary Portland cement
b. Rapid hardening cement
c. High alumina cement
d. Sulphate resisting cement

45. Gypsum is added in the manufacture of Portland cement in order to

a. Shortening the setting time of cement
b. Lengthening the setting time of cement
c. Decrease the burning temperature
d. Decrease the grinding time

46. Plain cement concrete is strong in taking

a. Tensile stress
b. Compressive stress
c. Shear stress
d. All of the above

47. Toughness test is performed on materials that retained on sieved no.

a. 9.50 mm
b. 6.40 mm
c. 4.75 mm
d. 2.36 mm

48. Which one is not the aggregate consensus property

a. Coarse aggregate angularity
b. Fine aggregate angularity
c. Flat and elongated particles
d. Clay contents
e. Toughness

49. Which material has high packing factor

a. Gravel
b. Sand
c. Clay
d. Silt
e. Clay collides

50. Aggregate gradation having most particles of a large size of a small size with very few particles of an intermediate size is known as;

a. Well graded
b. Poorly graded
c. Uniformly graded
d. Gap graded
e. Densely graded

Answers:
coming soon...