What is D50 riprap?

D50 = riprap diameter in feet. Thickness: The minimum thickness of the riprap layer shall be 2.2 times the maximum stone diameter (for a D50 of 12” or smaller), but not less than 6 inches. For D50 specified greater than 12 inches, the riprap layer thickness shall be 2 times the D50.

What is rock slope protection?

Slope Protection consists of rock, concrete, or concreted rock or slope paving. ROCK SLOPE PROTECTION ROCK SHOULD DEMONSTRATE. Stability: Angular shapes may be used on any planed slope. Durability: Resist degradation and have a durability of 52 minimum (Caltrans) Consistency: Product is the same load after load.

What size is d50 rip rap?

From Curve 22-5, it can be found that the riprap for d50 = 3.4″ and 4.52″ will both be stable on a 2.5:1 side slope. This design procedure applies to riprap protection of shorelines surrounding open bodies of water, such as lakes, bays, estuaries etc. against the erosive action of surface waves.

How much area does a ton of riprap cover?

35 to 40 linear feet
The average is usually from about 3″ to 8″ in size. One ton of rip rap will usually cover an area of 35 to 40 linear feet, spread 3′ wide.

What is RSP fabric?

Rock slope protection (RSP) fabric serves the same purpose. As with filter fabric, RSP fabric is placed between RSP and the underlying foundation material. Section 13, “Water Pollution Control,” provides specifications for placing silt fence fabric, gravel filled bags, sediment filter bags, and temporary cover.

When to use the new Caltrans riprap gradations?

These supersede the previous Caltrans Riprap Sizes. Caltrans requires the use of these new RSP gradations starting August 1st, 2016 in new projects and those not yet at 30 percent PS&E stage. Rock grading and quality requirements per Standard Specifications.

How are the sizes of riprap rocks determined?

For method A placement and the class of RSP described, comply with the rock grading shown in the following table: a For any class, the percentage of rock smaller than the smallest rock size must be determined on the basis of weight.

How big does a rock layer have to be to pass Caltrans test?

If the rock layer is shown as 4-inches thick, comply with grading shown in the following table: Granular material must contain at least 90 percent crushed particles when tested under California Test 205.

What does the construction manual do for Caltrans?

Construction Manual. The Construction Manual contains policies and procedures related to the duties of Caltrans Division of Construction personnel, is for information only, and is intended as a resource for personnel engaged in contract administration. Be alert for new or revised specifications that may affect the current manual guidance…