Repairing Concrete Damages in Reinforced Structures

There are sure advances that should be considered so as to choose whether abandoned concrete needs repair or not, and determine legitimate repair procedure and material if repairing is required.

These repair steps would guarantee a fruitful repairing process that is done proficiently and successfully without exercise in futility and cash. Repair of concrete is required every once in a while as the structure gets old because of a few reasons. These steps are discussed below.

1. Decide Causes of Concrete Defects: The assurance of makes that drove the deformity ought to be done appropriately so as to handle the issue. In the event that the reason for damage is killed or declined, as it were, the repaired basic part would be increasingly solid and have a more extended assistance existence without the requirement for upkeep.

Be that as it may, in the event that the mindful factor of concrete damage can't, at that point a similar concrete imperfection can rehash itself later on and may bring about the misuse of cash and endeavors.

It ought to be realized that multiply or a few elements may add to the concrete deformity viable. Right now, the elements should be managed in any case the repair work would not meet its objectives.

Variables that may adversely affect the solidness and uprightness of the concrete structures are awful climate, cavitation, scraped area, fortification erosion, synthetics assaults, carbonation, breaks, plan and development deformities, and maturing of the structure.


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Published By
Rajib Dey
www.constructioncost.co
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Standard Staircase Dimensions in Buildings

Functioning as a system of steps leading people from one level of the building to another, a staircase is a pretty complex building element. This is because staircases have particular geometry and function. Everything about this building element needs to be carefully planned because of that.

The dimensions of the steps and regulations of the heights and widths of the steps need to be carefully maintained. Not only that, you need to pay attention to the material being used as well.

In this article we will discuss the standard staircase dimensions today.

In staircase design, concrete offers great reliability in terms of load-bearing and production benefits. Geometry requirements, heat resistance and tensile strength, all can be fulfilled by using concrete. The staircases that are made of in-situ concrete can be adapted to any building plans on site.

On the other hand, precast staircases are not as flexible and can only be fitted into predefined design dimensions specific for that staircase design.

However, one advantage of using precast staircases is that they can be produced efficiently, faster and more cleanly than in-situ staircases.

It goes without saying that special attention must be paid to the basic dimensions of the stair breadth and rises. You should also need to take care of dividing the staircase with proper landings in order to enable resting places in a long climb. The number of steps without an intermediate landing should be counted in this matter.

Staircase dimensions are an important part of staircase safety. This page covers all of the important staircase measurements and a mistake to watch out for.

Staircase design has to account for the human step sizes and the comfortable distance a human foot can travel vertically.

The tread size is dictated by the average adult foot size. Though it is not necessary to fit your entire foot on the stairs, it should be kept as close as possible in order to keep it as safe as possible. The standard tread size is 10 inches minimum, or 25.4 centimeters.

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Published By
Rajib Dey
www.constructioncost.co
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Steel Quality Field Test

It is essential for the constructors to have good quality material for their building project. Compromises in the quality of construction material can cause severe results leading to serious repercussions. One of the most important materials of a building is the steel reinforcements used in concrete columns, beams, and other structures.

The quality of steel received on site determines the strength of the structure with steel reinforcements inside it; so it is imperative that you check the steel quality right on the project site to ensure that your building will be made out of materials capable of handling the load.

Observations on Steel on Site:

1. Cleanliness: The reinforcements that you receive in the field must be clean ones. Dust, rust, earth, mild scales, paint, oil, grease or any similar coating clinging to the bars is detrimental to the bonding between reinforcement and concrete. Also, these contaminants can cause corrosion in the structure. For this reason, you must make sure that the steel bars and other reinforcements you receive are clean. Point to note: a little rusting on the bars is considered to be helpful in forming better bonds with the concrete. But excessive rusting and/or scaling is absolutely harmful for the building.

2. Manufacturer Marking: The bars should have their steel grade, manufacturer name/logo, brand name, diameter etc should be embossed on themselves. Do check if you have received everything of the same type as you expected.

3. Bending the Bars: When satisfied with the above, proceed to the Bend Test to examine the actual capabilities of the steel you have received on site, under realistic strain.

a. Bend Test: This test should be carried out as per the specifications in IS 1599 and you should use mandrels of size specified in IS 1786. The rebar sample should be bent in 180 degrees, results recorded, and then proceed to bending it 180 degrees.

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Published By
Rajib Dey
www.constructioncost.co
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Relocation of Structures

Sometimes, it is required to move a building from one place to another location. This can be required for a number of reasons, like change of land, replanning of facility or even natural causes. In such situations, a process called Structure Relocation comes into play.

Relocation of a structure essentially involves three steps. The first is to disassemble the existing structure - you need to tear the building down systematically, preserving as much material and objects as you can. The second step is transporting the disassembled building blocks to the intended target location.

This may need the involvement of heavy transport support if the location is far away. Of course, if the location is within the same property then this step reduces next to zero. The last and the most important step is to reassemble the building back again at the target location using the same building blocks from the previous structure and maybe some extra materials.

Sometimes if the building is small enough and light enough, it can be picked up as a whole and transported to the new location with minimal disassembly and reconstruction necessary. If the move is within the same piece of property, the move can be done by rolling it on temporary rails or rollers. For long distance moves, generally heavy-duty flatbed trucks are used. Though in that case many complications may arise on the way, like roadside obstacles like narrow zones, and overhead obstacles like low-hanging branches and cables.

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Published By
Rajib Dey
www.constructioncost.co
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Impact of course aggregate on mix design of concrete

Coarse aggregate is considered as one of the vital elements of concrete and captures the major volume in the mix as well as impacts the concrete mix design significantly. Its different characteristics like strength, maximum size, shape, and water absorption affect water demand, the quantity of cement and fine aggregate in concrete mixture.

It is found that high maximum coarse aggregate size can reduce water demand in the mixture as such aggregate contains lower surface area with regards to small coarse aggregate size.

While considering shape, rounded type aggregate offers reasonable mix design for normal strength concrete.

For high strength concrete, angular coarse aggregate is essential. The scope of segregation is reduced when coarser aggregate is graded perfectly for concrete mix design.

While considering strength, greater aggregate strength generates higher concrete strength.

1. Maximum Aggregate Size: The maximum size of coarse aggregate is another vital factor that checks water demand to attain definite workability. It also determines the quantity of fine aggregate content required for developing cohesive mix.

For a specified weight, if the maximum size of aggregate is increased, the surface area of coarse aggregates is reduced and conversely. When the maximum size of coarse aggregate is decreased, the surface area of coarse aggregate is raised. If the surface area is large, the water demand will be increased to coat the particles and produce workability.

For smaller maximum size of coarse aggregate, larger fine aggregate content is required to coat particles and retain cohesiveness of concrete mix. Therefore, for similar workability, 40mm down aggregate contains lower water/cement ratio, thus strength is raised with regards to 20mm down aggregate. Due to its lower water demand, higher maximum size of coarse aggregate can reduce the cement consumption.

Maximum size of aggregate is confined with clear cover and minimum distance among the reinforcement bars. Maximum size of coarse aggregate is lower than clear cover or minimum distance among the reinforcement bars. As a result, the aggregates can get through the reinforcement in congested areas, to form dense and uniform concrete.

2. Grading of Coarse Aggregate: Grading means the establishment of the particle-size distribution for aggregate. It influences the amount of cement and water requirements, workability, pumpability, and stability of concrete. The grading of coarse aggregate is crucial to acquire cohesive and dense concrete. The voids due to larger coarse aggregate particles are filled with smaller coarse aggregate particles.

If the grading of coarse aggregate is perfect, the scope of segregation is reduced, specifically for higher workability and the compatibility of concrete in enhanced. The coarse aggregate grading limits are provided in ASTM C33/ C33M and IS 383 – 1970 – table 2, Clause 4.1 and 4.2 for single size aggregate as well as graded aggregate.

3. Shape of Coarse Aggregate: The shape of coarse aggregates range from round, angular, or irregular. Rounded aggregates contain lowest water demand because of lower surface area, and also contain lowest mortar paste requirement.

These properties facilitate to produce rounded aggregate to give in the most reasonable mixes for concrete grades up to M35. However, for concrete grades of M40 and above the scope of bond failure would slant the balance in support of angular aggregate containing larger surface area.

Flaky and elongated coarse aggregate particles raise the water demand as well as the susceptibility of segregation. The flexural strength of concrete is minimized due to flakiness and elongation. Specifications provided by Ministry of Surface Transport confine the combined flakiness and elongation to 30% by weight of coarse aggregates.

4. Strength of Coarse Aggregate: Material strength of coarse aggregate is determined by crushing strength of rock, aggregate crushing value, aggregate impact value, aggregate abrasion value. The IS limits for above tests range from Aggregate Crushing value, Aggregate Impact value, and Aggregate abrasion value.

5. Aggregate Absorption: The purpose of aggregate absorption is to employ a correction factor for aggregates in dry condition and find out water demand for concrete in saturated surface dry condition. Aggregate can consume water up to 2 % by weight when remains in bone dry state. But occasionally, the aggregate absorption remains as high as 5%.

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Published By
Rajib Dey
www.constructioncost.co
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Variation among Working stress method and Limit state method

This construction video shows the variation among working stress method and limit state method.

The basic variance among Working state method (WSM) and Limit State method (LSM) is that WSM stands for an elastic design method while LSM stands for a plastic design method.

In elastic design method, the design strength is estimated in such a manner that the stress in material is controlled with its yield limit, under which the material adheres to Hooke's law, and therefore, the word "elastic" is utilized. This method is used to produce cost-effective design of simple beam, or other structural elements where the standard for evaluating the design is stress (static). But, in case of changing the evaluation standard to other factors like fatigue stress, both the methods will give similar design. Also, WSM substantially reduces the calculation efforts.

In plastic design method the stress in material is permitted to go outside the yield limit and move into the plastic zone to attain extreme strength. Therefore, the "moment-rotation" power of beam, as for instance, is applied for creating more cost-effective design. However, because of the deployment of the non-linear zone, this method comprises laborious calculation.

Given below, some other general differences:

1) Serviceability check if LSM is necessary since after the elastic region strain is greater, it leads to more deformation, therefore a check is required.

2) LSM refers to strain based method while WSM is stress based method.

3) LSM refers to non-deterministic method while WSM is deterministic approach.

4) Partial safety factor is applied in LSM while Safety factor is applied in WSM.

5) Characteristic values (resulting from probabilistic approach) are applied in case of LSM while Average or statistic values are applied in WSM.

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Published By

Rajib Dey

www.constructioncost.co

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How MB Estimating Spreadsheet is useful for electrical, plumbing, construction, or other business

This construction video highlights the features of MB Estimating Spreadsheet. This construction estimating sheet is very useful to accelerate your estimating process with superior perfectness. This spreadsheet provides huge benefits for the professionals who associated with electrical, plumbing, construction, or other business.

This easy-to-use estimating sheet contains database sheet where all the records for material and labor names, rates, and lbr factors can be entered. To perform this, just choose the required material/labor and put the amount while making the estimation. One can create as many work stages as per choice and get complete view of all of the material/labor costs with individual stage and total cost.

Go through the following link to download this estimating spreadsheet.

Download MB Estimating Spreadsheet

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Published By

Rajib Dey

www.constructioncost.co

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HeavyBid provides great solution to your construction estimating & construction bidding process

HeavyBid is an easy-to-use construction estimating software that is widely applied in the sectors like transportation, utility, oil and gas, power, industrial, and commercial construction. It is found that over 35,000 estimators as well as 111 companies on the ENR Top 400 contractors list utilize HeavyBid in their projects. HeavyBid supports all the iPad and tablet devices.

Some of the crucial features of HeavyBid:-

• HeavyBid facilitates the users to produce and sustain live schedules through Primavera and Microsoft Project.

• HeavyBid supports your current accounting system to easily send your bid correctly to accounting for making budget.

• Automate the process for creating most of the estimates on the basis of your company’s historical estimating data, and quickly categorizing 100% subcontracted work and arranging it for quotes.

• The users can obtain numerous estimating data sources along with past estimates, standardized libraries tailor-made to your company, historical estimating costs, historical actual performance data, and incorporated RSMeans.

• Efficiently control the complete quote lifecycle from RFQ to picking subs and suppliers for producing subcontracts and purchase orders.

• Instantly evaluate sub and supplier quotes

• With easy-to-follow work breakdown structure allows the users to systematize your estimate on the basis of what matters the most to you (CSI, DOT, or custom WBS).

• Multi-level breakdowns facilitate the users to segregate big, composite work into smaller, more controllable and comprehensive pieces.

• Flexile labor and equipment cost methods aid the users to separate resource costs into their least levels of detail to form the most precise unit costs.

• Customizable cost types empower the users to track cost individually beyond labor, equipment, material, and subcontractor which are the vital part of the company.

• With multi-user networks, the users can get access to HeavyBid at the same time. Estimating data is consolidated and distributed, and estimators get the ability to manage their own estimates as well as several users can work up the identical estimate simultaneously.

Download a demo version

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Published By

Rajib Dey

www.quantity-takeoff.com

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Concrete Calculator for construction

Concrete calculator is a device of estimation. This handy estimatorwould simple needs measurement of feet and inches of length, width and depth of slab to entre for final measurement.

The outcome is so simply. The measurement will be in square feet, cubic feet and cubic yard of any specific project.

Now if the user of this calculatorenters the:

• Amount of waste
• Cost per yard of concrete
• Total cubic yard of concrete

Then the entirety cost will be shown in the text box. A user can differentiate concrete amount and material cost. They can add or minus on the total of it. You can put the percentage of waste product (optional) and press the input to get the result.

If the user wishes to enter other measurement, they have to click the clear button box. This will clear the previous data and users can enter the new one.

Concrete calculator is one of the important aspects of the construction project. It is important to fit the structural strength of the building. Concrete comes premixed in the concrete truck does not mean that the concrete is forever good.

Hole of any measurement with length, breath and depth needs concrete to fill up. The strength of concrete is also very important. Concrete uses the strength, which is 2000 psi (pounds per square inch) concrete.

Now days the buildings are pouring 3000 psi and 4000 psi concrete, depending on the size and complexity of the project.

Some of the bigger homes are designed by an architect and might require a structuralengineer. The structural engineer might require mix designs from the concrete company for his approval.

The requirement of slump is very necessary. There is a concept that the lower the slump the greater the strength but the harder the concrete is to work. The higher the slump the lesser strength & nbsp.

The engineer must know his/her limit to use the concrete. 3000 psi with a three to five inch slump is the limit to stay. The higher slump can jeopardize the situation.

Temperature of the concrete is a factor in summer and winter. Time spend in the truct is also a factor to concern. Foundation of concrete is not an easy thing, small-tint-little mistake could result big money loss.

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Published By

Rajib Dey

www.quantity-takeoff.com

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