A hydraulic capsule pipeline (HCP) transports solids as large cylindrical objects, or in cargo-carrying containers, by pipeline over long distances using water or another liquid as the carrier fluid. HCP was first proposed by Pyke during World War I1 (Lampe, 1959), and intensively studied from 1958 to 1978 at the Alberta Research Council-see Brown (1987) and Govier and Aziz (1972). More recent HCP research has been done at the University of Missouri by Liu and coworkers (Liu, 1981(Liu, , 1992. Based on the HCP concept, Liu and Marrero (1990) invented the coal log pipeline (CLP), a technology for transporting compressed coal cylinders. Application of HCP and CLP for solids transport over long distances requires the minimization of energy consumption. The research reported in this note explores the possibility of using high molecular weight polymers for drag reduction in HCP and CLP in order to reduce energy consumption.In HCP or CLP, a denser-than-fluid capsule becomes totally levitated or suspended by the flow when the fluid velocity reaches or exceeds a certain value called the liftoff velocity. By using dimensional analysis and experimental data, Liu (1982) deduced the following expression for the liftoff velocity:D is the pipe (inside) diameter. The absolute sign in Eq. 1 enclosing S -1 makes the same equation applicable to both denser-than-fluid capsules (S > 1) and lighter-than-fluid capsules (S < 1). At liftoff, the head loss (energy loss per unit weight of fluid) in the HCP is usually about 20% greater than without capsules at the same bulk fluid velocity. Richards (1992) found that the minimum energy loss and minimum abrasion (wear) to capsules and pipe occur at about V,. At or above the liftoff velocity, contact friction between capsules and pipe diminishes, and friction is dominated by turbulent energy dissipation. Under such conditions, energy loss is expected to be reduced by adding fibers or long-chain polymers, which are drag-reducing agents.

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Based on the status that the reinforced soil retaining wall (RSRW) is difficult to popularize in highway in high earthquake intensity region of China. The dynamic behavior of modular-block RSRW was investigated by large-scale shaking table tests. The standard soil was taken as the backfill. The concrete blocks were selected as panel. The geogrid was reinforcement. The failure mode of the wall was observed, and dynamic response and the displacements were measured. The results showed that, the middle of retaining wall panel was slightly bulged under the inputted earthquake motion, the mortar on the surface of wall was breaking down. When the input motion was WL2.0g (model scale: 1/2), the blocks at the top fell down, then the retaining wall was destroyed. The settlements of the soil and lateral displacement of the wall increased with the increase of the acceleration motion. The acceleration amplification factor is decreased with the increase of input acceleration. When the input acceleration was larger than 0.8g, the acceleration amplification factor of upper wall gradually is decreased less than 1. When model scale and inputting earthquake motion is different, the range of acceleration amplification factor is different. Shaking table tests results of RSRW with different panel forms and reinforced materials are summarized. The results show that seismic behaviour of RSRW is excellent. It is advise to revise some items of “Chinese Specification of Seismic Design for Highway Engineering” in order to promote the application of RSRW in highway.

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