石灰岩砂
1.From bottom to top, three parts of the Formation was subvided as: the lower sandy and silty limestone part (with molar-tooth-like veins, is 13-18m thick), the mid stromatolite limestone part (is 19-62m thick) and the upper sandy limestone part(with macroscopic fossils, is 7-10m thick), based on the characters of the lithology, event deposits, paleontology and correlation of different outcrops of the Formation.
2.A tough, silicified limestone formerly used to make millstones. It is typified by the presence of multiple cavities that originally housed fossilized shells.
3.The ratio of the volume worn away from PDC cutters to frictional works consumed during cutting rock was used as the rock abrasiveness index. The ratio values were in range 10 -6 mm 3/(kN·m) to 10 -3 mm 3/(kN·m).
4.The properties and influence factors of dolomite limestone-water glass grout were studied. Results show that its cohesion is low and flowability and stability are good, setting time can be controlled from 5 hours to 20 hours,calculus strength and mortar strength can reach 1-3 MPa, and the primary influence factors include liquid/solid ratio or the Baume degrees of water glass, curing temperature and humidity, size of limestone grains and different technique process.
