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.

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

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

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

Various components of an arch

Arch comprises of the wedge-shaped blocks formed with stones or bricks which provides collaborative support to one other. These are supported at the end through piers or abutments. Similar to lintels, an arch is constructed to bear the weight of the structure over the opening.
Given below the details of the various sections of an arch:


1. ABUTMENT OR PIER:
It belongs to the portion of wall or pier upon which the arch is supported.

2. ARCH RING:
It is a series of stones or bricks which contain a curve same as that of the arch.

3. INTRADOS OR SOFFIT:
It stands for the under-surface of an arch.



4. EXTRADOS:
It belongs to the external surface of an arch or the exterior curve of the arch ring.

Image Source : architechstok.wordpress.com

5. VOUSSOIRS OR ARCH BLOCK:
It stands for the wedge-shaped units to develop the arch are called voussoirs or arch stones or arch block.

6. SPRINGING STONE:
Springing stone or springer is the initial voussoirs at springing level on both side of the arch.

7. SPRINGING LINE:
It belongs to an fictitious line that connects two springing points.

8. CROWN:
Crown stands for the uppermost point of the extrados or it is the top part of the arch.



9. KEY-STONE:
It stands for the uppermost central wedge-shaped block of an arch.

10. SKEW-BACK:
It belongs to the surface of the abutment on which the arch is supported on.

11. SPAN:
Span refers to the apparent horizontal gap among supports.

12. RISE:
Rise belongs to the vertical distance among the springing line and the uppermost point on the intrados.

13. SPRINGING POINT:
Springing points belongs to the points at extremities of the intrados.

14. DEPTH OF ARCH:
The depth of the arch signifies the perpendicular space among the intrados and the extrados.

15. HAUNCH:
Haunch of the arch belongs to the part of the arch that is located centrally among the key and skew backs.

16. SPANDRIL:
Spandril stands for the triangular walling surrounded by the extrados of the arch, a horizontal line from the crown of the arch and a perpendicular line from the rising of the outer curves.

Article Source : http://www.dailycivil.com

Various types of cement with IS codes

In this construction video tutorial, the renowned civil engineer Parag Pal provides brief demonstration on various types of cement containing IS codes and characteristics of cement grades as well as various usages of cement.

Categories of cement :-

OPC (ordinary Portland cement) – It’s IS code is 269-1976 and it is utilized for general construction.

Low heat cement – It’s IS code is 269-1976 and it is employed for hefty construction.

Rapid Hardening Cement – It’s IS code is 8041-1990 and it is applied for eliminating formwork rapidly.

Pozzolona Cement – It’s IS code is 1489 – 1991 and is it used as good resistance to chemical.

High Strength Cement – It’s IS code is 8112 – 1989 and it is used for pre-stressed concrete.

Hydrophobic cement – It’s IS code is 8043 – 1991 and it is used for water proof construction.

Grade of cement is based on the crushing strength of a cement mortar cube of size 70.71 mm containing surface area of 51 cm². It is tested in 28 days.

For more information, watch the following video.

How to resist segregation in concrete

If the concrete mix is not uniform, the concrete components are detached and it is known as segregation in concrete. The flow test demonstrates the cohesion of the concrete mix. Due to inconsistency, the greater particles of concrete aggregate will detach and proceed towards the edge. Segregation may also occur when concrete mix is arranged on a sloppy surface. Usually, a cement particle intends to depart from the center of the concrete mix and abandoning the coarser material behind. It is difficult to quantify segregation but an expert can detect it easily.

The strength of a segregated concrete may change frequently and due to this cracking and leakages in concrete may occur. So, in order to retain the durability of your structure, the segregation of concrete should be avoided.

Given below, some helpful tips to get rid of or minimize segregation:

01.The concrete mix should have been correctly designed with finest quantity of water that is not too wet nor too dry.

02. Ensure the concrete is perfectly blended at the exact speed in a transit mixture for minimum two minutes. Examine the performance of mixer on daily basis relating to tolerable consistency of distribution of components in each batch.

03. Properly ship the concrete mix. Select the shortest route for shipping of concrete mix.

04. Arrange the concrete in its final position in quickest possible time. The concrete should not be arranged from large heights.

Image Source : onlinecivilforum.com

05. Formwork should be resistant against water in order that paste should leakage from the forms. Never vibrate formwork.

06. Do not let concrete to flow.

07. Utilize the vibrator properly and never utilize it to expand a heap of concrete over a bigger area.

08. Vibrate the concrete for just the exact time (not too long, not too less).

09. Apply chemical admixtures like air entraining agent in the mix. Entrained air minimizes the risk of segregation.

10. If any segregation is found in concrete, initiative should be taken for remixing to make it uniform again.

Article Source : https://gharpedia.com

Spreadsheet for rate analysis in RCC

This construction article provides brief explanation on how to make rate analysis for Reinforced Concrete (RCC) work.

To perform rate analysis, the initial step will be calculating the labour, materials, equipments and miscellaneous items toward specific quantity of reinforced concrete.


The next step should be finding out the element of structure for which the RCC rate analysis is applicable, because the quantity of reinforcement steel fluctuates with slabs, beams, columns, foundation, RCC Roads etc., while the quantity of other materials like sand, coarse aggregate and cement remain unchanged with the similar mix design (mix proportion) of concrete.

Image Source : theconstructor.org

Labour rates for reinforcement work modifies with type of structural element because the quantity of reinforcement steel modifies. The Quantity of materials like sand, cement and coarse aggregates fluctuate with mix design like M15 (1:2:4), M20 (1:1.5:3), M25, M30 etc..


Necessary data for RCC Rate Analysis:

1. Computation of materials
a) Bags of cement necessary
b) Volume of Sand necessary
c) Volume of Coarse Aggregate necessary
d) Computation of Reinforced Steel

2. Labour Requirement for 1m3 of RCC

3. Equipments and sundries

4. Contractor’s Profit

To gather more detailed information, go through the following link.
https://theconstructor.org/practical-guide/rate-analysis-for-reinforced-concrete/6954/