A low-profile batch plant has been installed on a San Diego Freeway con tract near Long Beach, consisting of two eight-cubic-yard mixers which will be charged through the use of belts. Production has not yet started, but it was reported that a similar unit was successful in another district. Also during the year a slip-form paving machine was used for the first time in this district on a freeway widening project. The machine is cur rently being used successfully on a Santa Ana Freeway contract, and the contractor plans to use it on a similar job in the near future. The construction industry is work ing to develop equipment capable of placing plastic strips to form the trans verse joints in concrete paving and thereby eliminate the need of sawing joints. A similar method of forming the longitudinal joints in multilane An interchange between the Golden State Freeway and the future Route 126 Freeway is under construc paving operations has been success tion at Castaic, on the Ridge Route north of San Fernando. The project is part of a program to improve fully used for some time. Transverse the Golden State (Interstate Route 5) .fo full freeway standards between San Fernando and the Kern county line. joints were placed in this manner on ' one section of the San Diego Freeway, and the finished product was of fairly good quality. Suppliers are continuing to develop techniques and equipment. Another experimental project was started to determine the value of ex pansive-type cement in the portland cement concrete pavement construc tion and to employ plastic sheeting as a curing agent. This experiment, con ducted on the Antelope Valley Free way, will evaluate the effect, if any, of expansive cement upon the place ment, curing and cracking of portland cement concrete pavements. Trans verse joints were eliminated in this experiment and the slab was allowed to crack at random. To date no sig nificant effects have become evident. Experiments in slope stabilization were started during the year, using new types of mulch to control severe erosion due to ocean fogs and winds. One special mulch consisted of proc essed garbage and refuse; another was a wood pulp derivative. Grass seed was introduced into the stabilizing ma terial and the mulches were sprayed on a test slope. No major problem was encountered in the application of the The Route 126 Freeway is under construction northeastward from Saticoy to Santa Paula through the materials; but conclusive results of the Santa Clara River valley in Ventura County. This 8.5-mile project, under contract for nearly $7,000,000, will be completed in mid-1965. This view is westward along the completed section toward Ventura. experiment are not yet available.
22 California Highways and Public Works