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DRY MIX MORTAR
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Submitted in partial fulfillment of curriculum prescribed for 1 ST semester M.TECH (Structural Engineering) From Maulana Azad National Institute of Technology, Bhopal
By, GOPINATH CHAPAGAIN
162111411
DEPARTMENT OF CIVIL ENGINEERING Maulana Azad National Institute of Technology, Bhopal
Maulana Azad National Institute of Technology Bhopal
CERTIFICATE
This is to certify that GOPINATH CHAPAGAIN bearing Scholar number 162111411 has successfully presented a seminar and submitted the seminar report on DRY MIX MORTAR in partial fulfillment of the curriculum prescribed for I Semester
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M.TECH ( STR UCTUR AL E ngineering ) of MAULANA AZAD NATIONAL INSTITUTE OF
TECHNOLOGY, BHOPAL during the year 2016. Dr. S. K. Dubey
(PG COORDINATOR AND PROFESSOR) OF CIVIL ENGINEERING)
Dr. P.K. JAIN
(HOD, DEPARTMENT
ACKNOWLEDGEMENT
I would like to express my deep sense of gratitude and heartfelt thanks to all the professors of Structural Engineering, MANIT, Bhopal for their constant encouragement, innovative ideas and guidance throughout this seminar. I am extremely thankful to all my friends and well-wishers for their never-ending support and encouragement.
Abstract: Dry mix mortar is an innovative idea in civil construction industry after ‘Ready mix concrete’. This is the product of completely dry, pre-mixed mortar for various application in ready to use condition after mixing with water as and when required. This is produced in fully automated mechanism with standard quality.It is also know as ‘REVOLUTIONARY CONSTRUCTION SOLUTION’. Lime-based and gypsum-based mortars have been used for thousands of years in the erection of building structures. In the past, these simple paste substance known as mortars have mainly been used as bedding materials for laying stones and bricks walls. However since 1950, the mineral binder within the mortar is gradually changed from lime and gypsum to cement as a result of easy availability of Port land cement.From that time onwards, the so-called job-site mortar technology has been introduced and applied in the construction industry worldwide.
TABLE OF CONTENT 1. Introduction
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2. Historical development of dry mix mortar
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3. Job site mortar Technology
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4. Dry mix mortar technology
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5. Raw materials used for fry mix mortar
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6. Production of dry mortar
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7.
Impact of dry mix mortar on sustainability
8. Yield of dry mix mortar 9. Advantages and disadvantages 10. Conclusion
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INTRODUCTION
Dry mix mortar is an innovative idea in civil construction industry after ‘Ready mix concrete’. This is the product of completely dry, pre-mixed mortar for various application in ready to use condition after mixing with water as and when required. This is produced in fully automated mechanism with standard quality. It is also know as ‘REVOLUTIONARY CONSTRUCTION SOLUTION’
HISTORICAL DEVELOPMENT:
Lime-based and gypsum-based mortars have been used for thousands of years in the erection of building structures. In the past, these simple paste substance known as mortars have mainly been used as bedding materials for laying stones and bricks walls.However since 1950, the mineral binder within the mortar is gradually changed from lime and gypsum to cement as a result of easy availability of Port land cement.From that time onwards, the so-called job-site mortar technology has been introduced and applied in the construction industry worldwide.
Fig.1 Dry mix mortar bags JOB-SITE MORTAR TECHNOLOGY:
The main ingredients of the job-site mortars are mainly cement and sand which are transported separately to the job sites and mixed together by hand in the appropriate ratio with the addition of water to produce wet mortars for simple applications.The quality of the site-mixed mortar depends on the quality of the raw materials, their correct batching ratio, the homogeneity of the mixture, and the consistency of the fresh mortar. Under these batch and mix conditions, the quality of the site-mixed mortars cannot easily be guaranteed. The major disadvantages of sitemixed mortars are that the whole manufacturing process cannot be controlled easily, and the
workers who make up the mortars cannot ensure the quality due to possible errors during various steps in preparing the mortars. With the above constraints and inconsistency, mortars based on job-site mix technology are unable to provide highly specialized properties of consistent performance.
DRY MIX MORTAR TECHNOLOGY:
In contrast to job-site mortars, the modern dr y-mix mortars are produced in a special factory with dedicated facilities on batching and blending of all the necessary ingredients in highly-controlled process. Factory premixed dry mortars ensure binders, fillers and chemical additives of known quality and are blended exactly in the same ratio as required thus ensuring high degree of product performance and consistency.The use of premixed dry mortars not only increases product performance significantly but also guarantees a high degree of application, reliability and consistency.
TYPES OF DRY MIX MORTAR PRODUCTS:
Basic grade: The basic dry mortar products are manufactured to replace the traditional
job-site mixed mortars with improved quality and enhanced consistency.
Technical grade : The technical dry mortars are advanced products developed to meet
latest building requirements and usually with distinct high performance properties which cannot be easily produced and achieved with job site mixed mortars.
THE RAW MATERIALS USED FOR PRODUCTION OF DRY MIX MORTAR:
Mineral binders
Fine Aggregates
Chemical Additives
PRODUCTION OF DRY MORTAR:
Well established dry-mix mortar production plant is normally equipped with computer controlled batching, dosing and mixing facilities. For some sizable plants, they also have their own sand drying and grading facilities to handle the production of graded sand.
For advanced dry mortar manufacturing plants with modern facilities, the production sequences are almost fully automatic with all the devices controlled and monitored by electronic sensors.
The automatic dosing system is usually very precise with extremely high accuracy especially for batching high performance chemical additives.The batching sequences and mixing cycles are specially designed for each product to ensure the powdery ingredients are blended to form a homogeneous mixture within the batch.For a highly efficient modern plant, the mixing time for each batch (say 2 Tons) may be as short as 2 to 5 minutes depending on type and complexity of the product. SCHEMATIC DIAGRAM SHOWING AUTOMATIC DOSING AND MIXING SYSTEM:
The primary impact of dry mix mortar on sustainability can be summarized into three main areas,
Durability
Quality
Efficiency
DURABILITY:
The extended durability offered by dry mix mortars can help to support long term performance and low maintenance of buildings.Offering better durability can also have a huge positive impact on cost savings.Dry mix products can be designed to meet various end-use requirements such as different climatic conditions, temperature variations etc. and can therefore be designed to survive different weather conditions. QUALITY
Dry mix mortars are manufactured in plants which are automated and have good process controls. This ensures proper weighing and dosing of various raw materials and additives and enables homogeneous mixing. Quality control is done for every cycles of dry mortar produced, meaning the same quality and consistency of the dry mix mortar can be guaranteed every time. Since the dry mix mortars are modified with polymers and additives, they offer excellent application properties, helps to ensure trouble free installation and ex cellent finishes.
EFFICIENCY:
One of the most important drivers for the growth of dry mix mortar was its very high efficiency. Use of dry mix mortar enables the use of machines for application which can result in huge time savings and more efficient use of materials, this in turn suppo rts very high productivity.
YEILD OF DRY MIX MORTAR:
Dry mix mortars typically contain a special additive which lower the mortar density and also helps to significantly improve the application properties.Dry mix mortars can provide better yield and thus better coverage compared to a standard site mix mortar, meaning material consumption will be less as compared to a standard site mix mortar. Typical site mix mortar has a density of approximately 2.1 – 2.2 kg / cub m, whereas for a dry mix mortar it is approximately 1.7 – 1.8 kg / cub m Here is an example on the amount of time one can save using a spray applied Cement base plaster vs. a site mix plaster from the UAE market. These data are for cement base plaster supplied in bags and applied by spray machines.
ADVANTAGES:
Dry mix mortar is a mixture of clean and properly proportioned ingredients, resulting in homogeneous mixture.No additional materials are required to be added while using except water. It reduces cracks, shrinkage and dampness on walls.It gives excellent smooth finish and more coverage Ingredients of dry mix mortar are completely cleaned in mechanical process and free from all foreign materials which causes dampness on walls. Use of dry mix mortar reduces plastering time and over all construction cost. It gives uniform and better finish. Excellent crack resistance. Easy application and no specialized skill labors are required.
DISADVANTAGES
Construction of plant is costly. Construction of plant requires large area. Transportation cost is required.
CONCLUSION:
Although, dry mortars cannot totally solve all the construction problems, they can at least provide a proper or more advanced materials approach to minimize the failure and enhance the durability of structures. Advanced dry mortars are very complicated powdery mixtures with sophisticated chemical additives of latest technology to provide wide range of superior performance to meet complex construction requirements.Advanced dry mortar products have been used with proven records in Europe and Western developed countries for a long time and the trend is still growing.
REFERENCES:
1. A. Konietzko: “The Application of Modern Dry, Factory Mixed, Mortar Products”, ZKG (Zement,Kalk,Gips) ACI, 48 (1985) no. 12, 625 – 659. 2. U. Dilger: “Ready-Mixed Mortar Production Plants”, ZKG (Zement,Kalk,Gips) ACI,
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(1985) no. 1, 2 – 6. 3. Y. Ohama, “Handbook of Polymer-Modified Concrete and Mortars – Properties and Process Technology”, Noyes Publications. 4. BS 4721 : 1981, “Specifications for Ready Mixed Building Mortars”, British Standards Institution.
