Dupont Zemdrain: A concrete problem solver
"A foolproof way to get high quality, high finish and highly impermeable concrete? You must be joking!" said an experienced structural consultant recently. The consultant admitted that he had been putting up exposed concrete structures, water retaining concrete structures and bridges for years, and had struggled with these basic issues all through. Dupont Zemdrain, then, is a dream comes true for him and many others.

What is Zemdrain?

DuPont Zemdrain are form liners used in civil engineering applications like bridges, tunnels, dams, water tanks and waste water treatment plants. To be precise, it is a controlled permeability formwork liner where longer life concrete is required in a project.

Why use form liners for concrete?

Dupont Zemdrain: A concrete problem solver
Concrete is a porous material and many of the problems with durability start with the quality of the surface of concrete. Aggressive elements like oxygen, salts, carbon dioxide and moisture attack the outer layer of concrete can penetrate it. Once these elements enter, they systematically decrease the strength and durability of concrete by increasing its porosity and over time, causing cracks and fissures. Dupont Zemdrain provides a near non-porous, dense skin with minimal capillaries guarding the concrete from liquid and gas attacks, by adding to its resistance.

What is Zemdrain made of?

It comes as a sheet made up of fine polypropylene fibers with numerous pores creating an air and water permeable membrane. Both sides of the fabric exhibit their individual properties and functioning.

Dupont Zemdrain: A concrete problem solver
The draining side is composed of either embossed black coarse fibers as in Zemdrain Classic or of a plastic uniquely shaped plastic grid as in Zemdrain MD. This side does the collection and evacuation of excess air and water from the concrete.

The filtering side holds back the cement particles giving a strong covercrete. The fine fiber bonded composition does not stick to the concrete. These are grey for Zemdrain Classic and white for Zemdrain MD. There is no release agent applicable for the product.

How exactly does it work?

When lining the formwork the material in fact drains away excess water from the cover zone of the concrete. The concrete so left behind is a protective and strengthening cover for the core and reinforcement that are guarded against aggressive elements. The surface is free from blowholes as it disperses air bubbles.

Dupont Zemdrain: A concrete problem solver
The Zemdrain treated concrete shows the properties of low porosity, greater strength and aesthetically enhanced surfaces. The draining side of the sheet collects air and water that are then evacuated at the shutter interface. The filtering side holds back the cement particles at the surface of the concrete. It is then most suitable for controlled permeability formwork lining for projects requiring long life concrete. This is true for civil engineering applications like bridges, tunnels, dams, water tanks and waste water treatment plants.

The Zemdrain advantage

Zemdrain offers a concrete structure with superior durability without additional treatment or chemicals due to the low w/c ratio obtained in the concrete cover zone. The liner allows a regulated evacuation of excess water and air from the fresh concrete while retaining the cement particles. There is no vacuum or soaking effect as the drainage is by gravitation. The cement type, additives used and the quantity of excess water determine the time taken for the process. Some of the excess water is retained by the sheet and goes towards the curing of the concrete.

Apart from the strength advantage the concrete offers resistance enhancement towards carbonation, freeze-thaw with salt, chloride diffusion, microbiological growth and reduced permeability.

Zemdrain Classic is the first generation product that has proved its performance on over 1 million square meters of concrete surface across the globe. Zemdrain MD, the second generation product was launched in 1997 and is already in use in several hundred sites worldwide. The installation process requires tensioning around the formwork to avoid folds for Zemdrain Classic. It can be used as a curing membrane when left on the concrete prior to its stripping. Zemdrain MD, the second generation product in the line, is stiffer and easier to fix.

As compared to 20% wastage generated in using Zemdrain Classic, only 2-5% waste is generates when you use Zemdrain MD. The new product is also easier to install and uses less manpower. Plus, it can be re-used up to three times, whereas Classic is not normally used more than once.

The last word

The panacea cure for exposed concrete structures and their related issues certainly seems to have arrived with Dupont's Zemdrain.

Zemdrain is now here in India and though it's been introduced recently, its popularity in such a short span of time is proof that this is a product that has, proverbially speaking, hit the nail right on the head.
Concrete Rheology - Unveiling the Secrets of Concrete
Concrete is a heterogeneous composite complex material, and its hardened property is influenced by its fresh property. Concrete today has transformed into an advanced type with new and innovative ingredients added - either singly or in

Read more ...

ICRETE: Making Concrete Economical
ICRETE offers many benefits apart from reducing cement content and giving high grades saving to ready-mix concrete companies; it helps reduce shrinkage and permeability in concrete slabs, increases the durability of concrete, and also works

Read more ...

UltraTech Cement to implement Coolbrook’s RotoDynamic HeaterTM revolutionary technology for industrial electrification
UltraTech Cement Limited, India’s largest cement and ready-mix concrete (RMC) company, and Coolbrook, a transformational technology and engineering company, will jointly develop a project to implement Coolbrook’s RotoDynamic HeaterTM (RDH)

Read more ...

Plastic Shrinkage and Cracks in Concrete
Plastic shrinkage cracking occurs when fresh concrete is subjected to a very rapid loss of moisture. It is caused by a combination of factors such as air and concrete temperature, relative humidity, and wind velocity at the surface of concrete. These can cause

Read more ...

Mechanised way of plastering with spray Plaster Machine
This paper covers the research work carried out on cement plastering process for internal and external building wall by using spray plastering machine. Objective of study is to experiment and compare the plastering activity by conventional way and

Read more ...

Construction Defects Investigation & Remedies
In recent years, the speed of construction has increased very fast; buildings which used to take 3-5 years are now getting completed in 1-2 years. There is a race to complete projects faster, but due to this speedy construction, the quality of construction is often

Read more ...

Challenges in usage of Hydrogen in Cement Industry
With its zero-emission characteristics, hydrogen has become a promising decarbonization path for the cement industry. While there are several issues that need to be resolved in the use of hydrogen, there are also many advantages, so much so that the growth

Read more ...

Enhancing Corrosion Resistance of Steel Bars in Reinforced Concrete Structures
Reinforced concrete is a composite material which is made using concrete and steel bars. Concrete takes the compressive forces and steel bar takes tensile forces. Concrete around the steel bar protects it from corrosion by providing an alkaline environment

Read more ...

Moving toward workability retention to rheology retention with low viscosity concrete technology
Amol Patil, Sr. Specialist - General Manager (Admixture and Specialty Products), Master Builders Solutions (India), and Nilotpol KAR, Managing Director, Master Builders Solutions (South Asia), present a paper on the concept of low viscosity concrete in

Read more ...

Cement industry innovating eco-friendly packaging
Cement companies are constantly innovating to meet global sustainability standards and improve logistics, shelf life, and utility of cement, while reducing wastage. Thei aim is to reduce their environmental impact without compromising their product

Read more ...

IIT Madras uses Solar Thermal Energy to Recycle Waste concrete
Researchers at the Indian Institute of Technology Madras have developed a treatment process using solar thermal energy to recycle construction and demolition debris. Waste concrete from demolition was heated using solar radiation to produce recycled concrete

Read more ...

Textile Reinforced Concrete - A Novel Construction Material of the Future
As a new-age innovative building material, TRC is especially suited for maintenance of existing structures, for manufacturing new lightweight precast members, or as a secondary building material to aid the main building material. Textile Reinforced Concrete

Read more ...

Technological Innovation for Use of Bottom Ash by-product of Thermal Power Plants in the Production of Concrete
The day is not far for the adoption of this innovative, eco-friendly, and cost-effective bottom ash – concrete process technology by construction agencies undertaking road/infrastructure project works, real estate developers, ready mix concrete (RMC) operators

Read more ...

Headed Bars in Concrete Construction
Using headed bars instead of hooked bars offer several advantages like requirement of reduced development length, less congestion, ease of transport and fixing at site, better concrete consolidation, and better performance under seismic loads.

Read more ...

Sustainability of Cement Concrete - Research Experience at CRRI on Sustainability of Concrete from Materials Perspective
It can be said that ever since the publication of the document of World Commission on Environment and Development [1], the focus of the world has diverted towards sustainability. Gro Harlem Bruntland [1] defined sustainable development as “development

Read more ...

Shrinkage, Creep, Crack-Width, Deflection in Concrete
The effects of shrinkage, creep, crack-width, and deflection in concrete are often ignored by designers while designing structural members. These effects, if not considered in some special cases such as long span slabs or long cantilevers, may become very

Read more ...

Concrete Relief Shelve Walls - An Innovative Method of Earth Retention
Relief shelve walls are a unique concept that use only conventional construction materials like PCC / RCC / steel reinforcements, and work on a completely different fundamental to resist the lateral load caused due to soil. Information on the various dimensions

Read more ...

Carbon Neutrality in Cement Industry A Global Perspective
Increasing energy costs, overcapacity, and environmental pollution are the top concerns of the cement industry, which is one of the major contributors to CO2 emissions. Dr S B Hegde, Professor, Department of Civil Engineering, Jain College of Engineering

Read more ...

Finnish company Betolar expands to Indian concrete markets with a cement-free concrete solution
Betolar, a Finnish start-up, and innovator of geopolymer concrete solution Geoprime®, has expanded its operations to Europe and Asian markets including India, Vietnam and Indonesia. Betolar’s innovation Geoprime® is the next-generation, low carbon

Read more ...

Why Fly Ash Bricks Are Better Than Clay/Red Bricks
It is estimated that in India each million clay bricks consume about 200 tons of coal and emit around 270 tons of CO2; on the other hand, with fly ash bricks production in an energy-free route, there are no emissions. Dr. N. Subramanian, Consulting

Read more ...