Quality management is a holistic approach towards maintaining the quality of a product. The article discusses the 360-degree approach to maintaining the quality of concrete at the site.
Overview of Soil Stabilization :Cement / Lime :PPTAniket Pateriya
Soil-cement is frequently used as a construction material for pipe bedding, slope protection, and road construction as a sub-base layer reinforcing and protecting the subgrade. It has good compressive and shear strength, but is brittle and has low tensile strength, so it is prone to forming cracks.
Lime can be used to treat soils to varying degrees, depending upon the objective. The least amount of treatment is used to dry and temporarily modify soils. Such treatment produces a working platform for construction or temporary roads. A greater degree of treatment supported by testing, design, and proper construction techniques--produces permanent structural stabilization of soils.
Overview of Soil Stabilization :Cement / Lime :PPTAniket Pateriya
Soil-cement is frequently used as a construction material for pipe bedding, slope protection, and road construction as a sub-base layer reinforcing and protecting the subgrade. It has good compressive and shear strength, but is brittle and has low tensile strength, so it is prone to forming cracks.
Lime can be used to treat soils to varying degrees, depending upon the objective. The least amount of treatment is used to dry and temporarily modify soils. Such treatment produces a working platform for construction or temporary roads. A greater degree of treatment supported by testing, design, and proper construction techniques--produces permanent structural stabilization of soils.
basic knowledge about performance and characteristics of fly ash based concrete. this was my first presentation....so hard core civil engineers might consider me a layman!... anyway its a good way to start knowing gist and basics.
Cement, Cement manufacturing, Types of cementNaresh Kumar
Cement, in general, adhesive substances of all kinds, but, in a narrower sense, the binding materials used in building and civil engineering construction. Cements of this kind are finely ground powders that, when mixed with water, set to a hard mass. Setting and hardening result from hydration, which is a chemical combination of the cement compounds with water that yields submicroscopic crystals or a gel-like material with a high surface area. Because of their hydrating properties, constructional cements, which will even set and harden under water, are often called hydraulic cements. The most important of these is portland cement.
Soil stabilization with cement, bitumen, lime, chemical stabilization,geotextile, grouting etc. are discussed. It is a method of improving soil properties by blending and mixing other materials.
Concrete Technology, PPT Based On Unit 1 (Cement)
In this PPT you Can studied about various method of Manufacturing of cement, properties and Test on cement.
By- Prof K.S.Somase
(Assistant professor of Gurukul Education society's Institute of engineering and technology, Nandgaon
basic knowledge about performance and characteristics of fly ash based concrete. this was my first presentation....so hard core civil engineers might consider me a layman!... anyway its a good way to start knowing gist and basics.
Cement, Cement manufacturing, Types of cementNaresh Kumar
Cement, in general, adhesive substances of all kinds, but, in a narrower sense, the binding materials used in building and civil engineering construction. Cements of this kind are finely ground powders that, when mixed with water, set to a hard mass. Setting and hardening result from hydration, which is a chemical combination of the cement compounds with water that yields submicroscopic crystals or a gel-like material with a high surface area. Because of their hydrating properties, constructional cements, which will even set and harden under water, are often called hydraulic cements. The most important of these is portland cement.
Soil stabilization with cement, bitumen, lime, chemical stabilization,geotextile, grouting etc. are discussed. It is a method of improving soil properties by blending and mixing other materials.
Concrete Technology, PPT Based On Unit 1 (Cement)
In this PPT you Can studied about various method of Manufacturing of cement, properties and Test on cement.
By- Prof K.S.Somase
(Assistant professor of Gurukul Education society's Institute of engineering and technology, Nandgaon
These presentations were created during the 2016–2021 B.Arch programme.
Please refer to the references column at the end of each presentation for the information within.
Foam Concrete - Properties and ApprilicationsRajesh Khanna
Foam concrete is a very fluid, lightweight cellular concrete fill material, produced by blending a cement paste (the slurry or mortar), with a separately manufactured, pre- formed foam. The density of foam concrete is determined by the ratio of foam to slurry and densities range typically between 300 and 1600 kg/m3.
Fresh concrete -building materials for engineersmusadoto
General introduction
CONCRETE
is a building Material made from a mixture of gravel ,sand ,cement,water and air ,forming a stone like mass on hardenning.
FRESH CONCRETE
It is a concrete that has not reached the final setting time.
Cement based building_materials_icr_aug2020Dr J.D. Bapat
Cite this paper: J D Bapat, Kalpana Karthikeyan, "Cement Based Building Materials", Indian Cement Review, August 2020, pp 48-51
The work on the following cement-based building materials has been covered: dry mix mortar plaster (DMM), cement-based fly ash bricks, AAC blocks and micro-concrete for concrete repair work.
Critical Path Explained With 7 Q&As and a Free Excel TemplateSHAZEBALIKHAN1
The critical path method is the most used project management technique. Learn the CPM with 7 FAQs ranging from definition to method, process, tests. The attached excel sheet (hyperlinked in the article) explains the implementation of CPM in a project schedule.
5 Project Risk Identification Tools I Use & How You Can Use Them TooSHAZEBALIKHAN1
Risk is an inherent property of a project. Risk identification is the first step in risk management. The article details the 5 risk identification tools that have helped me in my projects. The explanation shall enable you to use the risk identification techniques for your projects.
Top 20 Standard Contract Clauses Every Manager Should KnowSHAZEBALIKHAN1
A contract is the project bible. It includes several clauses that explain the terms and conditions. The article enlists 20 such clauses that are common and a part of every contract.
Residential Building Preliminary Cost Estimate- Excel TemplateSHAZEBALIKHAN1
The article simplifies the preliminary cost estimate for a residential building. The excel template (hyperlinked in the article) takes the basic inputs and estimates a residential building cost estimate. The estimate also breaks up the cost into 11 heads
3 Most Important In-situ Soil Tests for Construction WorksSHAZEBALIKHAN1
All the structures rest on the soil and hence the strength and other properties of the soil needs to be checked. The 3 of the most used field tests are sieve analysis, moisture content test and field dry density.
5 Must Know Types of Concrete Testing for Civil EngineersSHAZEBALIKHAN1
The five concrete tests explained in the article are basic and must do. The tests methods, procedures, relevant code are mentioned. Workability test, temperature test, setting time test, compressive strength test, permeability test.
Construction Project Schedule Template- Residential BuildingSHAZEBALIKHAN1
The excel template is a ready-to-use project schedule for a residential building construction project. The article gives the basic idea of a project schedule for residential building construction. Download the excel file through the hyperlink in the article.
All About Construction Labour Planning- Excel TemplateSHAZEBALIKHAN1
Planning labours for your project at the site is a cumbersome task. The article aims to explain the procedure in easy steps and best practices to follow. An excel sheet hyperlinked in the article is one of a kind and a must have labour planner.
Construction Material Estimate with MS Excel fileSHAZEBALIKHAN1
Learn the material estimation for PCC, RCC, Brick Masonry, and Plaster. A ready to use excel file is available to download through a hyperlink in the pdf.
Managing the Construction Claims EffectivelySHAZEBALIKHAN1
The article aims to explain the types of construction claims and their respective root causes. In the end, the best practices to minimise the claim are explained. A case study on time and cost overrun will detail out what claims arises due to delay.
How Does MS Project Works 6- Task Controlling FactorsSHAZEBALIKHAN1
MS Project is scheduling software. It takes multiple factors into account to schedule a task. The article explains all the inputs and their respective effect on the scheduling ability of the MS Project.
Most Popular 20 Evergreen Project Management TermsSHAZEBALIKHAN1
Project management requires a deep understanding of the jargon and terminology for effective implementation of practices. The article presents 20 popular and common terms of project management
My 5 Learnings of Waterfall Project ManagementSHAZEBALIKHAN1
The waterfall technique is also called the traditional method of project management. Learn about the 5 key takeaways and how you can implement the techniques in your project.
These five types of construction contracts are widely used across the world. Get to about the lump-sum contract, unit-rate contract, cost-plus contract, time & material contract, and target cost contract. All the contract types are explained with their respective example, pros and cons.
Project Time Estimation 6 Powerful Tips & TricksSHAZEBALIKHAN1
Check out the 6-time estimation methods for project & activity duration. The approaches are used worldwide and are proven to be effective and powerful.
Types of Building Foundations- Shallow and DeepSHAZEBALIKHAN1
The article explains the types of building foundations, i.e., shallow and deep. Further, the examples, uses, design criteria of each of the shallow and deep foundations have been described in detail.
DCMA has enlisted 14-points to assess the project schedule quality. The article explains each of the 14-points in detail and in simple language. Knowledge of these points shall help you to prepare a better and efficient schedule that can be prepared, managed and executed.
A contract agreement is the bible of a project. It contains all the terms, conditions, specifications, ifs & buts. To effectively execute a project, the contract needs to be managed. The article enlists all the steps of contract management.
Democratizing Fuzzing at Scale by Abhishek Aryaabh.arya
Presented at NUS: Fuzzing and Software Security Summer School 2024
This keynote talks about the democratization of fuzzing at scale, highlighting the collaboration between open source communities, academia, and industry to advance the field of fuzzing. It delves into the history of fuzzing, the development of scalable fuzzing platforms, and the empowerment of community-driven research. The talk will further discuss recent advancements leveraging AI/ML and offer insights into the future evolution of the fuzzing landscape.
Courier management system project report.pdfKamal Acharya
It is now-a-days very important for the people to send or receive articles like imported furniture, electronic items, gifts, business goods and the like. People depend vastly on different transport systems which mostly use the manual way of receiving and delivering the articles. There is no way to track the articles till they are received and there is no way to let the customer know what happened in transit, once he booked some articles. In such a situation, we need a system which completely computerizes the cargo activities including time to time tracking of the articles sent. This need is fulfilled by Courier Management System software which is online software for the cargo management people that enables them to receive the goods from a source and send them to a required destination and track their status from time to time.
Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
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Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
1. 1/9
Civilverse Admin 15 May 2021
Top 5 Concrete Quality Control Methods at Site
civilverse.org/concrete-quality-control
Table of Contents for Top 5 Concrete Quality Control Methods at Construction Site-
1. Introduction to Concrete Quality Control
2. Need of Concrete Quality Control
3. Tip 1: QC for Material Storage
4. Tip 2: QC for Preparing Concrete
5. Tip 3: QC for Handling
6. Tip 4: QC for Pouring Concrete
7. Tip 5: QC for Post-Pouring Concrete
8. Final Words
Introduction to Concrete Quality Control
Concrete is a mixture of cement, sand, aggregate and water. Concrete is an essential
building construction product. The cement binds the concrete elements together. The
sand fills the space between the aggregate and provide a larger contact area for cement
binding. The aggregate provides the bulk and strength to the concrete mixture. The lime
can also be used in place of cement but it has lesser strength as compared to the cement,
keeping all the other parameters the same. The concrete with lime is called lime concrete
and the concrete with cement is called cement concrete.
The concrete properties can be altered by adding additives to it. The concrete can be
further strengthened by reinforcing it with steel bars. Such concrete is called the
reinforced cement concrete or RCC, while the concrete without steel bars is called plain
2. 2/9
concrete or PCC.
The popularity of concrete is due to the various properties of concrete. The ability to set
on mixing with water, suitability to be cast into any shape, ease in handling, strength,
lower heat transmission, etc. and being economical than steel.
The primary requirement of the concrete is to provide strength. The strength of the
concrete is controlled by changing the ratio of its’ constituent. The concrete mix can be
prepared by any of the two methods- nominal mix and design mix. The nominal mix is
used for concrete grades up to M20. The nominal mix has a fixed ratio of the constituents
for each grade. The design mix is used for the high-performance concrete and the ratio of
the constituent is calculated for each grade.
Need of Concrete Quality Control
Every project has its’ own quality control program. The QC procedures, checks, control
methods, remedial measures are mentioned in the agreement. Moreover, one of the main
objectives of project control is to ensure quality.
Concrete quality control is necessary to ensure the strength of the structure. Quality
control has various aspects from selecting the right material to the curing of the concrete.
Every step involved in the process should be monitored for its’ quality compliance.
The quality maintained throughout the construction project not only helps in maintaining
the desired lifetime of the structure but also keeps aesthetics. Moreover, it creates a
reputation for the contractor, provides better value for money, lower maintenance cost
etc.
As per the research, the cost incurred due to the poor quality is 6-15% of the construction
cost for defective components and 5% for rework of defect. The reasons for the defects can
be either human error like lack of supervision, low-quality material, poor workmanship.
Tip 1: QC for Material Storage
The quality control starts with the material brought to the site. The materials have
properties that can be utilised only if it has been preserved. The material quality
deteriorates if its storage is improper.
The storage of material is to be done to protect it from pollutants and undesirable weather
condition. For example, the cement should be kept away from dampness, steel
reinforcement bars should be kept away from water source etc.
Following are the methods to store construction materials for concrete-
Cement-
3. 3/9
Cement Storage Shed
The cement should be kept away from moisture. The cement sets in the presence of
moisture and forms lumps. These lumps deteriorate the cement quality. The storage
should protect the cement from all weather conditions and have proper ventilation.
The storage area floor should ideally be of concrete to avoid moisture from the ground. If
storage is to be done on the ground, the storage area should be made 300 mm higher than
the ground surface. The cement bags should be covered with waterproof plastic or
tarpaulin. The storage area should also have a stable shed over it.
The storage area should be decided as per
the required stock built. Ideally, 10 cement
bags are piled up to facilitate the manual
loading and unloading. The storage is to be
kept in such a way that older stock can be
used first. Generally, the storage is kept for
3 times the daily consumption. The criteria
may change as per the delivery time,
storage conditions, cash flow etc.
Recordkeeping- To ensure the quality
following records should be maintained-
Delivery date
Manufacturing date
Storage location
The brand with cement type and
cement grade
Steel-
The reinforcement steel bars are prone to corrosion. To protect the steel bars from
corrosion, they should be kept away from the potential waterlogging area and covered
with waterproof plastic or tarpaulin. The steel bars should also be protected from foreign
materials that can reduce its’ bonding with concrete.
The correct method to store the bars is by providing the wooden sleepers beneath the
bars. The ground is made level and wooden sleepers are provided that maintain the 100
mm distance between the bars and the ground. The steel bundles should also be separated
into layers by the wooden sleepers.
Recordkeeping- The manufacturer’s test certificate for steel bars is to be kept in the
records. Samples taken randomly should also be tested as per the quality plan.
4. 4/9
Reinforcement Bars Storage Method
Sand and Aggregate-
Sand and aggregate accumulate the water and becomes bulkier. This can lead to a higher
water-cement ratio of the concrete. Thus, producing poor-quality concrete. To avoid this,
the water content in sand and aggregate is determined prior to mix and water content is
reduced suitably. The sand and aggregate are such stored that the water is naturally
drained out.
The storage of sand and aggregate is made on the slightly inclined ground. The shed
above the storage would prevent higher water content during the rainy season.
The other major concern is the mixing of pollutants. When piling up and reclaiming the
material stock, soil, twigs, dust and debris etc. gets mixed with it. Thus, the area should be
cleaned prior to the storage of the material and attention is to be paid when stacking.
Water-
The steel tank for storing the water should be treated with an anti-corrosion coating. The
water should be free from oil, grease or any other foreign material and should be potable.
Recordkeeping- The water is to be tested for suspended solids, chloride contents and
pH value prior to mixing.
Tip 2: QC for Preparing Concrete
IS 456:2000 recommends to collect the following minimum data before preparing the
concrete-
Type of mix, either nominal mix or design mix
Grade Designation
Type of Cement
Maximum nominal size of aggregate
Maximum cement content (for design mix)
5. 5/9
Maximum water-cement ratio
Workability
Mix Proportion (for nominal mix)
Maximum temperature of concrete at the time of placing
Degree of supervision
To ensure the quality a design mix should be prepared and tested for the target mean
strength.
Weighing for Concrete Quality Control
The accuracy in measuring the quantity of material should be ensured. The tolerance limit
as per IS 456:2000 for material variation in one batch is as follows-
Weight Tolerance limit of Material for Concrete Batching
The material should be proportioned only on the basis of weight. The volume
proportioning can be allowed if the actual bulk densities have been established.
Mixing for Concrete Quality Control
The mechanical mixing of the concrete is recommended. The mixing is generally done in
batching plants. However, for small scale production, portable concrete mixers can also
be used.
The batching plants have automated weighing systems and can provide the batch report.
The quality control is better. They operate on electricity. For better quality control, the
batching plants need to be calibrated for their weighing accuracy.
The concrete mixers are operated by attached engines operated by fossil fuels. The
production capacity is lesser than the batching plant. The concrete mixers are of two types
tilting drum type and reversing drum type.
Recordkeeping- Material quantity for each batch with, time, date, slump at the time of
dispatch, concrete samples for cubes.
Tip 3: QC for Handling
The chemical reactions in the concrete start as soon as the mixture is mixed with the
water. The reactions make the compounds that set the concrete. Thus, it is necessary to
timely transport, pour, compact and finish the concrete before it gets hard. The
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workability of concrete decreases with the increasing time. The fluidity is lost and the
finishing becomes difficult.
Transportation for Concrete Quality Control
The concrete supply should be continuous and the gap between the two batches should
not exceed 20 minutes. The casting should be monolithic. It is recommended, the
duration from mixing to pouring should not exceed. For higher transportation time,
suitable admixtures should be used to retard the setting of concrete.
The temperature change during the transportation should be calculated and suitable
measures to be taken to ensure the correct pouring temperature.
The concrete if transported for a short distance, dumpers can be used. For longer
distances, concrete millers are used.
Recordkeeping- In case of a concrete purchase from a supplier, the time of dispatch
and the time of arrival should be noted.
Tip 4: QC for Pouring Concrete
Cleaning of Surface
The pouring surface should be cleaned of dirt, dust, other foreign material by blowing air
or water.
Checking of Rebars, formwork and staging/scaffolding
The rebars should be checked for their diameter and arrangement as per the drawing. The
rebars should be strongly held into their position when pouring concrete.
The staging and scaffolding to be checked for their connections and load-carrying
capacity. The formwork used should be well oiled, straight and free from the defects that
may prevent the finishing.
Pouring
Concrete pouring should be done in layers of 40-50 cm for horizontal members. For
vertical members, the pouring should be 2-3 m in height per hour to avoid the lateral
pressure on the formwork. The allowable time between the two layers of pouring is 120-
150 minutes for a temperature below 25-degree centigrade else 60-120 minutes.
The concrete pumps, bucket or chute can be used for pouring. The capacity and
methodology of each piece of equipment are different from each other.
The concrete pumps can pour concrete in any direction and through long distances up to
500m. Their capacity ranges from 20-70 cum/hr. The pumps are of two types- piston type
and squeeze type. A slurry mixture of 1 cement and 3 sand is used prior to the pumping of
7. 7/9
concrete to avoid the choking of the pipeline. The minimum slump for the concrete to be
pumped is 80mm.
The bucket is used with a crane. The bucket has an opening and closing arrangement at
the bottom and offers lesser productivity and the least segregation.
The chutes work only vertically downward and diagonally downward. The funnel is
attached at the bottom to minimise segregation. The tip of the chute should not be more
than 1.5m higher than the pouring surface. The use of chutes is not recommended.
Compaction
The compaction of concrete is the process of removing air voids from the concrete. The
concrete becomes denser and achieves more strength than the uncompacted concrete.
The compaction of concrete is to be done by means of vibrators. The vibrator can be of
needle type or plate type. The diameter of the needle of the vibrator varies from 30mm to
60mm. The higher the needle diameter, the greater is the consolidation area. The vibrator
should comply with the IS 2505, IS 2506, IS 2514 and IS 4656.
The concrete is to be compacted at the outer periphery first and then at the centre of the
poured concrete. The vibrator should be vertically dipped into the concrete and taken out
and not be left in it for a long time. The prolonged exposure of concrete to the vibration
causes grout formation near the vibrator which is undesirable. The distance between two
vibration points should not exceed the 1.5m distance. The vibration of a very fine mix
should be avoided.
For slump lesser than 100 mm, the vibration time is 15-30 seconds, else 7-10 seconds.
8. 8/9
Finishing
The concrete surface should be made smooth with a trowel. No undulation, aggregate,
voids should be visible at the surface. If another layer is to pour over the surface, it should
be left rough and provide a shear key if possible.
The use of additional water or cement for finishing should be avoided. Further, the
concrete should not be disturbed once placed as it affects the strength.
Tip 5: QC for Post-Pouring Concrete
The concrete loses moisture after setting. This lost moisture needs to be made up by
providing external water so that the concrete can attain strength. The process is called
curing. The curing is the most important method of post pouring quality control of the
concrete.
The curing can be done by wet curing, liquid membrane curing, temperature control
methods.
The minimum curing period for OPC is 7 days and cement with mineral admixtures is 10
days. For, hot and dry weather conditions, the curing period should not be smaller than
the 10 days for OPC and 14 days for cement with mineral admixture.
Final Words
The best way to ensure the quality of concrete is by preparing the Quality Assurance Plan
(QAP) and implementing it strictly. The IS 456:2000 lays the foundation for QAP, further
ISO 9001:2015 lays the general guidelines to ensure the quality.
The effective implementation of QAP is to be done through the execution and operation
team only. The quality supervisor can only check and guide the execution team to
maintain the quality. Thus, the training of execution and operation staff is an important
9. 9/9
step of QAP implementation.
The 5 tips of concrete quality control plan as mentioned above will help in developing the
QAP.