PJMS132017-Rapid_Set_Cement_Specs.pdf

Rapid Set Cement

DESCRIPTION:

Rapid Set Cement is a hydraulic cement which is combined with aggregate and water to produce a rapid strength-gaining concrete. This cement is manu-factured by Rapid Set Products, Midwestern Regional Office, 1211 S. 6th St., St. Charles, IL, 60174, telephone (312) 773-4949.

AREAS OF APPLICATION:

For applications where quick strength of concrete is required including patching of portland cement concrete (PCC) pavements, sidewalks, and floors.

PHYSIOGRAPHIC FACTORS:

Rapid Set Cement is a hydraulic cement which is used to make rapid strength-gaining concrete. The manufacturer states that it is similar to portland cement in manufacture and use, and the chemical composition of the cement is the same as that of ASTM Type K Shrinkage Compensating Cement. However, Rapid Set Cement neither expands nor shrinks. The manufacturer claims that Rapid Set Cement concrete sets up and rapidly gains strength at low temperatures (to 22oF). The concrete is easy to place due to the high slump (6 ±1 in.). Time of setting can be controlled in the field from 15 to 45 min using Rapid Set Products Set Control retarder.

MANUFACTURER'S TECHNICAL DATA:

Freeze/Thaw Durability (ASTM C 666)

Number of Cycles Relative Dynamic Modulus (%)

72 97.9 180 89.1 252 84.1 300 82.4

Scaling Resistance to DeIcing Chemicals (ASTM C 672)

Number of Cycles Rating Condition of Surface

15 0 No scaling 60 1 Slight scaling 90 2 Slight to moderate scaling

TEST RESULTS OBTAINED AT USA ENGINEER RESEARCH AND DEVELOPMENT

CENTER (ERDC-WES):

Property Test Method Test Result

Compressive strength (psi) 1 hr ASTM C 109 2,140 2 hrs 2,650 3 hrs 3,020 24 hrs ASTM C 39 3,650 28 hrs

Flexural strength (psi) ASTM C 78 24 hrs 540 28 days 1,260

Bond to concrete (psi) ASTM C 882 24 hrs 1,920 28 days 2,680

Shrinkage, 24 hrs (%) duPont shrinkage gauge Unconfined 0.080 Concrete patch 0.007

Rapid freezing and thawing, ASTM C 666 relative modulus of Procedure A elasticity (%)

50 cycles 88 150 cycles 82 200 cycles 51

DISCUSSION AND RECOMMENDATIONS:

The manufacturer states that the concrete mixture proportions should be the same as those used for a PCC patch except Rapid Set Cement shall be sub-stituted for portland cement using the same weight of Rapid Set Cement as portland cement. The mixing water should be adjusted to obtain a slump of 6 ±1 in. The use of an air-entraining admixture is recommended for areas sub-ject to severe freezing and thawing. The manufacturer should be contacted in regard to the appropriate types and dosages of air-entraining admixtures. A retarder, Rapid Set Products Set Control, can be obtained from the manufac-turer, and temperature dictates the amount of retarder to be used. Under-sanded mixtures may segregate when the retarder is used. Should segregation occur, add additional sand to the mixture. Rapid Set Cement Concrete is mixed, placed, and finished the same way as conventional concrete except that the concrete should be placed within 15 min after addition of the mixing water.

In January 1986, concrete made with Rapid Set Cement was used to repair streets at Maxwell AFB, AL. The concrete was mixed in a mobile mixer. The mixture proportions for the concrete are given below:

Material Amount

Rapid Set Cement 650 lbs Sand 1,700 lbs 3/8-in. gravel 1,300 lbs Water 300 lbs

A patch located on 3rd St. and measuring 3 ft by 18 ft by 4 in. deep was moni-tored. Numerous cracks were observed after 1-1/2 years in service. In March 1986, four areas of the airfield pavement at Tyndall AFB, FL, were repaired with concrete made with Rapid Set Cement. The patches ranged from 16 to 40 sq ft in surface area and were full depth. The concrete was mixed in a mobile mixer and the mixture proportions were similar to the mixture used at Maxwell AFB.

After 2 years of service, the patches performed well.

SUMMARY:

Concrete made with Rapid Set Cement has been found to be a rapid strength-gaining concrete that can support aircraft within 1 to 2 hrs. Air-entrain-ing admixture should be added during mixing if the concrete is exposed to freezing and thawing. Full-depth patches made with this concrete have performed satisfactorily at Tyndall AFB.

ADDITIONAL INFORMATION:

Chief, Airfields and Pavements Branch

ATTN: CEERD-GM-A

Phone: 601-634-2731 Fax: 601-634-3020 Email: Don.R.Alexander@erdc.usace.army.mil mailto:Don.R.Alexander@erdc.usace.army.mil