
Dry mix shotcrete powder set-retarding admixture
BATIMIX Ret DG2-P is a powder set-retarder for shotcrete based on selected gluconate modified organic polymers. It does not contain any corroding ingredient that could potentially attack steel, aluminum, or zinc embedments.
BATIMIX Ret DG2-P delays concrete setting to allow for placing and finishing operations, particularly in hot climates. It is used to transport shotcrete over long distances or cope with delivery schedules lengthened by traffic jams.
BATIMIX Ret DG2-P extends setting times, eliminating cold joints between adjacent shotcrete layers in large concrete-pours, or if casting rates are very-slow.
Shotcrete prepared with BATIMIX Ret DG2-P is characterized by the following:
In the plastic state:
In the hardened state:
BATIMIX Ret DG2-P is not a hazardous material. However, it should not be swallowed or allowed to come into contact with skin and eyes. Suitable gloves and goggles should be worn. For additional information, kindly refer to the product’s Material Safety Data Sheet.
BATIMIX Ret DG2-P complies with ASTM C 1141 requirements for Type I (dry mix shotcrete), Grade 2, Class B (powder).
The optimum dosage of BATIMIX Ret DG2-P on slump retention, setting times, and hardening is best determined by trials using the actual shotcrete formulation with site materials under conditions that will be experienced in the field. As a guide to such trials, the addition rates shall vary from 0.2% to 0.8% of the cementitious materials. Dosages outside the specified range may also be used if necessary to meet particular mix requirements.
It is to be noted that the free water content should be reduced when designing shotcrete mixes with BATIMIX Ret DG2-P to maintain similar W/C.
An overdose of BATIMIX Ret DG2-P will produce a slight increase in shotcrete workability with significantly higher slump retention and setting retardation as compared to that normally obtained. However, if the shotcrete is properly cured, the ultimate strength will not be impaired by such setting retardation.
BATIMIX Ret DG2-P is compatible with all other Batimix admixtures incorporated in the same shotcrete. During batching, all admixtures should be added separately to the shotcrete mix as this may alter their performances. BATIMIX Ret DG2-P is compatible with all types of Portland cement and replacement materials such as silica fume, fly ash, and blast furnace slag.
Automatic dispensing systems should preferably be used to introduce the correct quantity of BATIMIX Ret DG2-P in the shotcrete mixer. This admixture should not be directly introduced on the dry cement. It should rather be added after incorporating around 2/3 of the mixing water, and in any case prior to introducing other chemicals such as water reducers.
For proper products usage, Holderchem S.A.L. provides complete technical and laboratory support as well as on-site assistance pertaining to concrete mix design, admixture selection, materials testing, and dispensing equipment.
BATIMIX Ret DG2-P has a minimum shelf life of 12 months if kept unopened and stored at temperatures ranging from 2 to 50 ºC.