| The tiles is one of important overburden layer materials in the building industry. Iiles not only provides the surface of the adornment of esthetics interest, but also has advantage of function,such as water resistant, stiffness, hygiene as well as easy to clean.The mortar which is always mixed in the construction site and the characteristics by thick layer is used for bonding tiles. The method not only has low workability and big material dosage,but also don't assure quality, separation are often happened. New style of thin layer tiles can carry on applying mortar on large areas, workability and quality consumedly raise.This kind of technique needs the mortar that have the function of good workability and good water retention capacity and long to open time, and good slipping resistant. Research on extra is limited in the past,there is extra fine sand mortar that its fine degree modulus is less than 1.0 in Chongqing and some other eares, the sand is possessed of beyond 95% in project.Extra fine sand bond mortar is characterized by bad water retention capacity, big brittleness , low toughness, bad durability, and it exist that tiles probable seperated from wall. The mortar adopt a thick layer to bond tiles, low workability, big wasted, because it is short to open time, and bad slipping resistant.In this paper, the influences of fine degree modulus,C/S,sediment content of aggregate and cement grade on bond mortar are studied;The effects of kinds and content of redispersible powde on bond strength, cellulose ester, starch ether, the early strength agent on mortar thin-layer workability of tile bonding, furthermore, polypropylene fiber on dry shrinkage, toughness and cracking resistance, are emphatically analyzed. The effect of modification with agent on workability, adhesive, anti-cracing and climate resistant are systemically discussed. The researches in this paper show that:(1) When the extra fine sand is mixed in bond mortar, the suitable ratio of C/S is 1:1.2, Sediment content should be less than 5%, P.O42.5R is suitably mixed in bonding mortar. Test results indicate that vinyl acetate-ethene polymers can well provide the high adhesive strength, construction, flexibility, the suitable dosage of RP is 1.5%～2%; The experiment show that water retention capacity, slipping resistant ability of fresh mortar and open time bond strength are all improved significantly, when addition of hydroxypropyl methyl cellulose ether is mixed, Generally, the suitable dosage of hydroxypropyl methyl cellulose is 2～2.5kg/m~3; Starch ether additivea is applied for anti-slipping,open time, the suitable dosage is 0.03～0.05%; The early strength agent was added into mortar, the mortar's slipping resistant ability, early bond strength are improved, the suitable dosage of early strength agent is 5～7kg/m~3; When the mortar was mixed in Polypropylene fiber, the cracking resistance is improved greatly, brittleness and dry shrinkage falls obviously, Its suitable dosage is about 1kg/m~3.(2)By modification with vinyl acetate-ethene polymers, hydroxypropyl methyl cellulose ester, starch ether, early strength agent and polypropylene fiber, one extra sand mortar used as tile bonding was prepared with good workability, adhesive capacity , climate resistant and flexible. The test results indicate that this mortar has some excellent performances such as good slipping resistant, little slippage amount less than 0.5mm, sufficient open time and bonding strength over 0.5 MPa after opening for 20 minutes, which meets the need of thin-layer construction of tile bonding.
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