WHAT is Flowable Fill? Flowable fill is a self-compacting low strength material with a flowable consistency that is used as an economical fill or backfill material as an alternative to compacted granular fill. Flowable fill is not concrete, nor it is used to replace concrete.
This mixture is capable of filling all voids in irregular excavations and hard to reach places (such as under and around pipes), is self-leveling, and hardens in a matter of a few hours without the need for compaction in layers.
|MIX||CONTRACTOR PRICING||LIST PRICE|
|Flowable Fill||$140.50 /cy||$146.00 /cy|
|2000 PSI||$151.50 /cy||$157.00 /cy|
|2500 PSI||$154.50 /cy||$160.00 /cy|
|3000 PSI||$157.50 /cy||$163.00 /cy|
Hardening of flowable fill mixes containing 5 percent cement (that is sufficient to support the weight of an average person) can usually be expected in about 1 to 4 hours. Within 24 hours, construction equipment is usually able to move across the surface of the flowable fill without any apparent damage.
Flowable fill is defined as a material with compressive strength less than 1200 psi (8.3 MPa). Most applications, however, use mixtures with strength less than 300 psi (2.1 MPa).
For example, during the building process a spring or external water source may be disturbed causing water leaks in a basement dig. The ideal way to stop the flow of water is to use flowable fill. Once the fill hardens, it can be re-dug with vertical walls and construction can continue in a dry space.
As described in ASTM D 6024, the test involves dropping a steel ball five times on the surface of the hardened material and measuring the diameter of the impression. If the diameter is 3 inches or less, the material is able to have backfill or pavement placed over it.
1.01 DESCRIPTION Control Density Fill ( CDF ) is used as a low strength, self consolidating fill material for confined spaces which can be easily excavatable at a later time. CDF may be used as a trench backfill, structural backfill, pipe bedding, or pipe filling for abandonment in place.
For example, in areas with harsh winter weather, a 7 bag mix, 4,000 PSI concrete and as much as 8% air content help avoid spalling of the concrete surface. In effect, the rule of 6’s is a great guide for most concrete work, but like almost any rule, exceptions should be made when necessary.
Concrete Prices Per Yard By PSI Mix
|PSI Mix||Price Per Cubic Yard Delivered|
|3,000 PSI, 6.0 Sack Mix||$124|
|3,500 PSI, 6.5 Sack Mix||$126|
|4,000 PSI, 7.1 Sack Mix||$129|
|5,000 PSI, 8.5 Sack Mix||$147|
In the earlier days of ordering concrete, the concrete contractor would simply ask the ready- mix supplier for a mix based on the number of bags of Portland cement added, i.e. 5 bag, 6 bag, ect. High amounts of Portland help contribute to shrinkage cracks along with too much water.
Definition: self-consolidating cementitious mixture that is intended to result in a compressive strength of 1200 psi (8.3 MPa) or less.- ACI Concrete Terminology. A controlled low-strength material ( CLSM ) is a self-consolidating, cementing material used primarily as a backfill as an alternative to compacted fill.
At an average cost of $2.50 per square yard, slurry seals allow for a life extension of roughly 5-7 years for a quarter to a third of the cost of major road reconstruction. In addition, the seal prevents moisture and air intrusion in the pavement and improves skid resistance.
Unshrinkable Fill: means a mixture of aggregates, cementing material and water, with or without chemical admixtures, that hardens into a material with higher strength than soil but less than 0.4 Mpa compressive strength at 28 days, that can be removed with hand tools.
Flowable fill is a controlled low-strength material made of cement, fly ash, water, sand, and typically an air-entraining admixture. This mixture is useful for backfilling utility trenches, mud jacking, pipe bedding, abandoned sewers, and many other applications.