Sunday, 3 December 2017

Geotextile - Benefits for improving soil quality

Geotextiles are mostly utilized in the civil construction, particularly in roads and fills to make the quality of the soil better. Geotextiles can transform a poor soil to be stronger and prepare it for developing building. Geotextiles are very effective for varuiys infrastructure works like roads, harbors etc.


Function of Geotextiles

The objective of Geotextiles is to enhance the characteristics of soil so that roads, embankments, pipelines and earth retaining structures can be easily constructed on it.
Based on the uses, there are different types of geotextiles like open mesh type, warp-knitted structure, or with a closed fabric surface (a non-woven). According to uses or projected design, geotextiles are dependent on the various factors like separation, filtration, drainage, reinforcement, sealing and protection.


Geotextile Separation

If the geotextile is to be set up among two diverse soil materials, the separation factor is very important. Here, the geotextile will divide and sustain individual unrelated materials to retain the necessary soil characteristics. This type of geotextile is applied so that the soils are not blended when water enters into the soil strata. It is found in road construction, when it is required to maintain fine subgrade aggregate from coarse aggregates which are arranged as the base course.

It is performed to retain the drainage characteristics perfect by resisting the fine aggregate from filling the voids among the larger aggregate. These types of geotextile contain extra density and permeability characteristics to resist soil contamination and facilitate the water to pass smoothly devoid of damaging the strength and structural integrity of the road.



Geotextile Applications

Geotextiles are utilized for various purposes - To enhance the quality of unpaved and paved roads in airport runways; on landfills and stone base courses; underneath sidewalks and sand drainage layer; below parking lots and curb areas; To enhance green areas and recreational facilities, underneath retaining wall structures; To make the soil quality better, below duct banks and pipe trenches.


Geotextile Filtration

Geotextile Filtration facilitates water to pass in both directions. It can be woven or non-woven to resist fine aggregates to proceed among soil layers. In order to choose perfect one, evaluate and examine the porosity and permeability of the projected geotextile. Keep in mind that geotextiles are employed on both axis, vertical and horizontal. Geotextile with perfect porosity and permeable can facilitate resolving drainage problems over the house and roads and curbs. The geotextile advocates a lateral flow thus dispersing the kinetic energy of the capillary rise of ground water.



Geotextile Reinforcement

When a geotextile is used to improve soil characteristics, it shall consider the following criteria: friction or movement restraint, support of loads and changes in bearing failure plane.

This is comparable to the function of rebar in concrete, that it is used to reinforce concrete. This is why geotextiles are used on embankments and roads being built over very poorly graded soils. It will allow also to have a steeper embankment built, although it is always recommended to have that information provided by the geotechnical engineer.

Geotextile Sealing

When a geotextile is impregnated with asphalt or other mixes it will turn into an impermeable fabric that will restrict the flow of liquids in both directions.it is important to highlight that this will only occur if the geotextile is a non-woven fabric as normally is used in road improvements projects. There are multiple options and types of geotextiles but the remember that always the suggestion needs to come from a soil expert based on the information gather from existing soil strata.

For more information, go through the following article.
https://www.thebalance.com/construction-materials-4073376

Monday, 27 November 2017

Benefits of using plastic formworks in concrete construction

Plastic formworks in concrete construction are used to retain newly arranged concrete in place to provide adequate strength. Formworks facilitate to manage concrete efficiently and produce different types of shapes and forms.

Various types of materials like timber, steel, and aluminum are applied to develop formworks. Plastic is considered as best for formworks in relation to other materials in terms of strength, cost-effectiveness, and adaptability.



Sufficient time is required to develop the formworks. Formworks comprise 20 to 25% of the total cost of the structure. The security, cost, quality, and speed of a construction work mainly depend on formworks.



Plastic Formworks System



Benefits of Plastic Formworks in Concrete Construction

Plastic formworks provide various benefits like longevity, cost, and flexibility. Formworks consume huge labor force and total cost of the project. It is recommended that a formwork system should be cost-effective and assembled, disintegrated and managed smoothly by labor.

The plastic formworks provide the following benefits to the concrete construction:

Economical
Labor-friendly
Eco friendly
Low maintenance
Flexible

Plastic Formwork System
Certain grade plastics are used to build up formworks. There are not any chemical reactions among poured material and the plastic form. No patch on the surface of the reinforce concrete element exists.

Leakages
Resist leakages with water or newly arranged concrete from various parts of the form by fitting different parts of the system accurately.

Labor-friendly system
Plastic formworks are considered very labor-friendly system. It accommodates and plugs smoothly and significantly lightweight with regards to other types of formwork systems.



Nailing and oiling
Nailing and oiling plates are not necessary. Auto-leveling of plugging system can retain plates level automatically. It takes fewer time to install and disassemble.

Cleaning
Plastic forms can be cleansed with water without difficulty. Plastic forms can be broken due to handling in an inefficient manner as well as use of low voltage hot air gun for sealing.

Plastic forms can be easily reprocessed and they are eco-friendly to minimize handling time and great re-usability index.


Article Source : https://www.cforcivil.com

Tuesday, 14 November 2017

How to estimate concrete in cubic yards

This is a nice presentation from Jerry Howard. In this video, one can learn how to estimate the concrete slabs precisely.

As an example, a rectangular concrete pad is taken with 40 feet length, 12 feet width and 4” thickness.



To find out the volume of this concrete pad, apply the following formula :-

V = L x W x H = 40 x 12 x .334 (4” is converted to feet by dividing with 12) = 160.32 ft3

But, if you want to purchase concrete from any company, they sell it in cubic yards. So, you have to convert unit of measurement from cubic feet to cubic yards.



To do this, you have to apply the following trick :-

160.32 ft3/1 = 1 yd3/27 ft3 = 160.32/27 yd3 = 5.9 yd3 = 6 yards (approx) [as one cubic yard = 27 cubic feet)


Image Source : http://cementech.com

Friday, 3 November 2017

Types of ties applied in building construction

Ties stand for continuous tensioned reinforcements to be fully anchored and adequately lapped through welding. Given below, different types of ties found in building construction :-
o Peripheral ties
o Internal ties
o Horizontal column and wall ties
o Vertical ties


Peripheral Ties in Building Construction
Peripheral ties are generally set up at roof and floor level and it arranged at 1.2m distant from the perimeter wall or edge of the building. The peripheral ties have the capability to resist a tensile force similar to the smaller of 60KN or an amount calculated in accordance with the following equation.
Ft = 20+4no -> Equation-1


Here:
n denotes the number of storey of the structure
The area of steel bars needed for the peripheral ties should be calculated in relation to the following equation:
Ast=Ft / (0.87fy) -> Equation-2


Ast denotes the steel area required for peripheral ties
Ft denotes tensile force to be combated by peripheral tie 
Peripheral ties should have been anchored and lapped effectively.
Image Source : theconstructor.org



Internal Ties in Building Construction
Internal ties are arranged at roof level and floor level in two directions almost perpendicular to each other.
Internal ties should have been efficiently continuous along their length and attached with both ends to the peripheral ties or bolted to the columns or perimeter walls if such ties are continuous to columns or perimeter walls. 
The highest distance among internal ties is similar to the 1.5 times the greatest distance among centers of vertical loading elements in the direction of ties.
The internal ties should resist a tensile force identical or exceeding the force calculated in accordance with the following formula:
Tensile force = 0.0267(gk+qk) lFt -> Equation-3
Here:
(gk+qk) defines the sum of average characteristic dead load and live load applied on the floor. These quantities are calculated based on the specifications of Eurocode.
To gather more information on other types of ties, go through the following link.
https://theconstructor.org/building/what-are-the-types-of-ties-used-in-building-construction/19000/?utm_source=pushengage&utm_medium=push_notification&utm_campaign=pushengage

Saturday, 28 October 2017

How to calculate various parts of horizontal circular curve

In this construction video tutorial, S.L. Khan, the renowned civil engineers, gives brief lectures on how to define various parts of horizontal circular curve ranging from road curve, railway track curve or other structure curve.


By going through this tutorial, you will gather knowledge on curve length, curve chord length, tangent length, mid ordinate, apex distance, radius if chord and mid ordinate are recognized.


In the video, there is a horizontal curve and deflection angle is taken as Ø = 1000 and radius of the curve is taken as R = 500 ft.
It is known fact that in circular curve deflection angle and central angle are same.


On the basis of the above dimension, you have to determine the followings :-
  • Curve Length
  • Curve chord length
  • Tangent Length
  • Mid ordinate
  • Apex distance

These are the unidentified parts of the curve.
Solution :-
Computation of Tangent Length :-


Tangent length stands for the distance among tangent point of the curve and intersection point of the curve. For the calculation purpose, the following formula is used :-
Tangent Length = R tan Ø/2
So, T.L = 500 x Tan(50) (as the value of tangent is equal to halt deflection angle)
So, Tangent Length = 595.87 ft.
To find out the value of curve length, curve chord length, mid ordinate and apex distance, watch the following video tutorial.

Friday, 27 October 2017

Super Civil CD - A very useful construction program for civil and structural engineers

Super Civil CD is a powerful construction program specifically designed for Civil, Structural engineers as well as architects, students and construction professionals.

The software comprises the following :-

80 numbers Design Softwares along with RC, Steel, Dynamic Foundation, Ductile Detailing, Mix Design, Road, Drain, Rate Analysis of 63 items of Building Construction etc.




179 Excel based standard design & detail sheets  in concrete, steel & architecture. It comprises of the following :-

  • 65 nos. of Concrete Detail Sheets
  • 46 nos. of Structural Steel  Detail Sheets
  • 27 nos. of Foundation Detail Sheets
  • 41 nos. of Architectural Detail Sheets


200 numbers standard design tables / charts for Reinforced concrete & Steel.

110 numbers standard truss design & details up to 30.0 m span including horizontal bracing.

12 numbers standard purlin design & details up to 12.0 m span.



15 numbers electrical/instrumentation rack design & details sheets.

19 numbers standard specifications, design basis/ practice & project management system.

6 numbers complete tenders together SOQ programs.

28 numbers check lists for design & construction.

This software is available in CD. It supports Window 98 / XP / Vista.

To download the software, click on the following link
http://www.supercivilcd.com/indexy.htm

Wednesday, 25 October 2017

Reinforced Concrete Design: Design Theory and Examples, Third Edition – An exclusive book for civil engineering students

Prab Bhatt, Thomas J. MacGinley and Ban Seng Choo have jointly written an exclusive construction book for global construction professionals. The book is titles as Reinforced Concrete: Design Theory And Examples, 3rd Edition.

The book provides design theory for concrete components and structures as well as demonstrates the hands-on experience usages of the theory.

The third edition abides by the most updated standards of BS 8110 1997, the code for structural use of concrete; and BS 8007:1987, the code for making design of structures to maintain aqueous liquids.


Reinforced Concrete: Design Theory And Examples, 3Rd Edition



The book is specifically published for the students undergoing civil engineering degree courses to facilitate them to learn the theories of element design and the methods for creating the design of concrete buildings. The book will be also very fruitful for new graduates who just commence their career in structural design.



Various new illustrations and sections are included in this book, specifically the chapter on slabs is significantly elaborated with widespread coverage on Yield line analysis along with Hillerborg’s strip method and design for predetermined stress fields.

Besides, there are four new chapters to include the contents of university courses in design in structural concrete. The new chapters focus on the design of prestressed concrete structures, design of water tanks, a short chapter comparing the vital clauses of Eurocode 2 as well as a chapter on the basic theoretical characteristics of design of statically indeterminate structures.



The book comprises of over sixty evidently worked out design examples and more than 600 diagrams, plans and charts as well as provides brief explanation on the British Standard and Eurocode and highlights the variations among the codes. There are new chapters on prestressed concrete and water retaining structures as well as the most commonly faced design issues in structural concrete.

One can purchase the book online from Amazon by going through the following link.
https://www.amazon.in/Reinforced-Concrete-Design-Theory-Examples/dp/0415307961

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Published by Rajib Dey
Content Editor at www.sketchup3dconstruction.com
Email : globalrajib71@gmail.com


Geotextile - Benefits for improving soil quality

Geotextiles are mostly utilized in the civil construction, particularly in roads and fills to make the quality of the soil better. Geotexti...