4 Advice to Choose a Rubber Water Stopper

Concrete…it’s the universal medium. It’s used more than any other artificial material in the world. In fact, concrete’s use in modern society is exceeded only by that of naturally occurring water.

With competitive price and timely delivery, Hengyang sincerely hope to be your supplier and partner.

It’s the perfect medium for water retaining and water excluding structures such as dams, viaducts, swimming pools and basements.

But a concrete structure is only as watertight as the construction or expansion joints in that structure.
This is where concrete waterstops come in.

The main difference between PVC waterstops and swellable waterstops is that PVC types are generally cast 50% in to one pour and the remaining 50% is then cast into the second pour. This creates a physical barrier in the joint. The waterstop is effectively locked in both pours and water cannot pass through from either direction.

Swellable waterstops on the other hand are typically adhered on to the face of the first pour once the slab has set. The waterstop will then begin swelling when it comes in contact with the water from the second pour. It can expand by over 200%, thereby creating a pressure seal.

Hydrostop is used as a waterstop between two new concrete structures. The two main types of Hydrostop are centrally placed and externally placed. In short, the centrally placed, or centre stop, is placed in the centre of the pour.

Typically speaking, the width of the waterstop is determined by the thickness of the concrete. I.e. a 250mm thick slab requires a 250mm waterstop. However, this will usually be specified by an engineer.

The externally placed waterstop, or rearguard waterstop, is placed at the back of the join between the two pours. This is typically adhered to formwork.

Of these two types of waterstop, there is a further two common variations – waterstops for an expansion joint or construction joint. The expansion joint waterstop features a “centre bulb” which allows for expansion and contraction of the joint where as the construction joint has no bulb.

There are numerous other specialised waterstops such as:

TX waterstop – where a PVC waterstop is required between existing and new concrete.
XB waterstop – is a smaller PVC profile and is used where traditional waterstops conflict with reinforcing.
Copper waterstops – are predominately used in water retaining structures such as dams, hydro plants or water treatment facilities where they are subject to very high hydrostatic heads of water pressure against the join.
SureShield (TPER) – a chemical resistant “cast in place” PVC waterstop for joints subject to high chemical exposure

For more information regarding these specialised waterstops, or to find out what waterstop is suitable for your project, contact our friendly team at Allcon by clicking here. 

Like PVC waterstops, there are several different types of swellable waterstops for various applications and are typically manufactured from bentonite clay or a rubber compound. Whilst each type differs in some regard, there are some crucial things to consider when selecting one for your project.

Wet/Dry Cycling: As we know, swellable waterstops expand to create a compression seal when exposed to water. If there is no more water or moisture present, the waterstop will typically shrink in size, some slightly, some back to their original size. When water or moisture appears, the joint swells again, creating the seal.

However, lower cost waterstops can deteriorate as the joint cycles from wet to dry which can result in a partial or complete failure of the joint.

Minimum Concrete Cover: This refers to the minimum distance (cover) required between the waterstop and the concrete face. Due to the expansive nature of swellable waterstops, if the waterstop is too close to the face of the concrete, the pressure created could blow the face of the concrete out, compromising the joint. If this were to happen, it is extremely difficult to rectify.

While some waterstops may seem cost effective, they require a large, sometimes impractical minimum cover. When used incorrectly, it can lead to a joint failure and a very expensive repair job.

Expansion Delay Coating: Some waterstops incorporate an expansion delay coating that prevents the joint from absorbing water from the concrete or from inclement weather before the second pour is placed. This is especially useful if the waterstop needs to be placed in advance and may be left exposed to the elements before pouring.

If the waterstop doesn’t have an expansion delay coating and the joint gets rained on prior to pouring, the joint could pre-expand, significantly reducing its effectiveness.

Head Pressure: This refers to the head pressure the waterstop can resist when properly installed. Head pressure is the pressure created from the height of the water above the joint. The greater the height and volume, the greater the pressure.

Whilst not crucial in some applications it is an important consideration when specifying waterstops. Swellable waterstops are typically used to seal horizontal and vertical construction joints to poured in-situ concrete.

For more information, please visit Rubber Water Stopper.

Hydrotite is available in 2mm, 7mm and 10mm thicknesses and all feature an adhesive strip backing to enable adhering directly to the concrete surface. The thickness should be verified and approve by the consulting engineer on any project, however below is a general guide for the use of Hydrotite in various construction joints:

• 2mm – pipe penetrations, horizontal construction joints
• 7mm – pipe penetrations, horizontal and vertical construction joints
• 10mm – horizontal and vertical construction joints

There are other profiles of Hydrotite available for leak repairs and z-bar holes etc.

Finally, Hydrotite is not affected by wet/dry cycling, has an expansion delay coating, has a minimum cover of 50mm and is capable of sealing a 30m head of water.

Get Started: Researching Homeschool Science   Curriculums  Teaching homeschool science is a great way for families to personalize their child's education while giving you the flexibility to teach it your way. There are many wonderful science curriculums...

Frog dissections are a great way to learn about the human body, as frogs have many organs and tissues similar to those of humans. It is important to determine which type of dissection is best for your student or child. Some individuals do not enjoy performing...

Are you trying to choose the best microscope for your home or classroom? A science microscope is both an enjoyable and important tool for science education that will last for years to come. And unless you are a seasoned science educator, you probably have some questions about how to choose the right one for your specific needs! This article will explain the main types of microscopes and help you choose the best one for your home or class environment.

OPEN FOR ONLINE ORDERS HST Coronavirus News Update > SHIPPING UPDATE: Like many other suppliers and retailers, many people and businesses alike are experiencing delays of product delivery. At Home Science Tools, we are happy to report that we have been able to...

Learning the right programming language is an important first step in your career plans. You'll find more job opportunities by learning to code in a popular programming language. Programming is more than a STEM occupation. Computer code runs our electronic world!...

Are you interested in learning more about Pneumatic Fenders? Contact us today to secure an expert consultation!