With our Rip Rap Calculator, you will learn what is rip rap, how to calculate it, and its specifications. You can calculate rip rap in cubic yards, cubic feet, or tons. Also, you can calculate for example how much area does a ton of rip rap cover.

You can use riprap or gravel as a decoration around your pools. If you have a garden pool and do not know how much water do you need in it, our Pool calculator will help you. 

Rip Rap – What is Rip Rap?

Riprap (Rip Rap) is a geotechnical engineering construction material used to protect the surface of a dam from erosion. Riprap is often placed on a bank or slope to protect the hill from wave erosion. It is usually made of large, angular pieces of rock.

Riprap is an excellent choice for stabilizing the banks of rivers, streams, and other waterways. Riprap is made of concrete, rocks, or gravel and is installed along the bank of a river. You can call Riprap “spillway rock” because it keeps the banks of spillways from eroding.

Rip Rap Sizes – How to Calculate?

When you divide the length of the rip rap with the width, you get the size of the rip rap. For example, if a rip rap is 4 feet long and 2 feet wide, the length of the rip rap is 8 feet, and the width of the rip rap is 4 feet. 

What is rip rap rock? You can use this term to describe a form of construction made from large enough rocks or gravel which are not to be easily moved by waves. They are often strategically placed to help shore up a coastline. The rock’s size determines the rip rap rock size. You can use Rip rap rock to help shore up a coastline and create a structure to protect against erosion.

To be effective, you need to estimate the appropriate size for your riprap. Our Rip Rap calculator will help you calculate the amount of material and the number of cubic meters. This tool helps to determine the size of the riprap rock for the required length of the shore.

With the help of the Isbash equation, you will get results very quickly. Below we will show you the equation:

D_{50} = \frac{V^{2}}{2\cdot g\cdot C\cdot (S-1)}

D50 represents the average diameter of 50% of the spherical rocks for rip rap expressed in meters;
V is the designation for the average channel speed in meters per second;
g is the acceleration of 9,806 m/s²;
C is the Isbash constant whose value is equal to 0.86 for a turbulent water flow or 1.20 for a water flow whose turbulence is significantly lower;
S is the designation for the specific weight of the rock, whose value ranges from about 2.50 to 3.00.

Rip Rap Specifications

 Here are the specifications of Rip Rap:

  • You can use it to prevent erosion in many areas, such as on the banks of rivers, streams, or shorelines.
  • It is durable and has a long lifespan. 
  • You can install it at the edge of a river or stream to prevent erosion in areas with a lot of water.
  • It is made of stone, which means it is less likely to move or shift when placed in an area.
  • You can install it with the help of machinery so that it can be installed in a short amount of time.
  • It can be custom-made to fit any type of shoreline. 
  • It is cost-effective and affordable.

Limestone Rip Rap is a rock product you can use to protect a shoreline from erosion. It has a rough surface and a rough texture. It can be used to form a wall or slope. The application of this product is primarily useful in construction.

The Rip Rap Retaining Wall is a simple and durable solution for building a retaining wall. You can make a wall of crushed stone mixed with a mixture of cement and water. This mix is then pushed into a wall shape and covered with a synthetic mortar. The Rip Rap Retaining Wall is strong enough to withstand heavy water and excellent for outdoor projects.

Rip Rap Size Chart

Rip Rap comes in a variety of lengths, widths, and heights. It is essential to measure the length and width of your project area before you buy Rip Rap. If you wonder what size you need, you can use the riprap size chart to help you. With the help of this chart, you can determine which size is best for your needs. It will show you how many bags of each size you will need to fill your surface. This chart will also tell you how many square feet of coverage you will get for each size.

The velocity of flow (ft/s)Size of Riprap (in)Minimum layer thickness (in)
Rip Rap size chart

Rip Rap Calculator – How to Use?

With the help of our calculator, you can calculate the D50 or the maximum water speed that supports riprap with a certain D50. Follow these steps to get results:

  • Firstly, enter the speed of the water.
  • Secondly, choose a constant for your riprap.
  • Thirdly, enter the weight of the price (your supplier can provide this information).

On the other hand, you can also calculate how much riprap you need in weight and volume.

  • For starters, you need to select the “rip-rap volume” option.
  • Then enter the dimensions needed to cover the surface and depth of the ripper. This way, you will get the desired result (volume and weight of riprap),
  • You can also enter the desired waste for your project.
  • In addition, you can enter the rock density in our calculator.

Practical Example

With an example, we will best explain the use of our calculator. We will use the example with an open canal and line it with riprap. The water flowing through this canal is relatively mild, say an average of 3.0 m/s. Next, we need the size of the stone, which the recipient delivers to us, and let it be 3.5. With the help of the formula we have already explained (Isbash equation), you can calculate the average diameter of the rock, and it looks like this:

 D_{50} = \frac{V^{2}}{2\cdot g\cdot C\cdot (S-1)} 
D_{50} = \frac{3^{2}}{2\cdot 9.086\cdot 1.44\cdot (3.5-1)} = \frac{9}{70.6}= 0.1274 = 12.74 \;cm

To sum up, with the help of a calculator, you can find out what ratio of rocks you need, so the example is 12.74 cm at an average water speed of 3.0 m/s.


What is a rip rap?

Riprap is a natural, coarse material used to construct levees, dams, and other flood control structures. The primary application of the material is to protect the site from water erosion. The material is a mixture of gravel, sand, and stone that you use for supporting structures.

How to install rip rap?

You can install Rip rap by dumping rocks from a barge or a truck and using a pneumatic or hydraulic machine to push the stones into place. Also, in riprap, you can create a sea wall to protect the coast from waves and currents.

How do you calculate rip rap?

One way is to measure the amount of material needed for the desired thickness. For example, if you need 2 feet of fabric, you will need to measure out 4 feet of rip rap. The other way is to measure the amount of material necessary for the desired length. For example, if you need 1 foot of material, you will need to measure out 2 feet of rip rap.

How much area does a ton of riprap cover?

The average size of a ton of riprap is about 1.2 yards. A ton of riprap covers estimate 320 square feet. Two tons will cover around 640 square feet.

How much does rip rap cost?

The price depends on the location as well as the material. Typically, riprap costs range from $25 to $75 per cubic yard. When we talk about grouted ripe, the price goes from $40 to $60 per square yard.

 How long does rip rap last?

The materials that strong enough to withstand great weight. They also have a high strength-to-weight ratio. Riprap is such a design that it can last a long time with adequate maintenance.