2011-024 - Laserfiche WebLink

Home Browse Search

LIME ROCK BASE COURSE 1 ) DESCRIPTION A) Under this item , the Contractor shall construct a lime rock base course upon the completed stabilized subgrade . The base course shall be constructed in accordance with the lines and grades and typical section as shown on the drawings . 2) MATERIALS A) The Contractor may use lime rock for the base course from either the Ocala Formation or the Miami Oolite Formation at his option , provided it meets the Specifications contained herein and complies with Section 911 " Lime rock Material for Base and Stabilized Base" of the 1986 Edition of Florida D . O . T . ' s Standard Specifications for Road and Bridge Construction . Only one of the two grades of lime rock shall be used on the project . B) The material shall be crushed or broken up to such size , before being placed on the road , that not less than 97 percent will pass a 3 1 /2 inch sieve and it shall be graded uniformly down to dust . All fine material shall consist entirely of dust of fracture . 3 ) PLACEMENT OF MATERIAL A) After the subgrade is completed and approved , the Contractor shall furnish and spread the lime rock in a uniform distribution . Segregated areas of fine or course rock will not be permitted . Such areas shall . be removed and replaced with properly graded rock . B) After the spreading is completed , the entire surface shall be scarified and shaped so as to produce the required grade and cross section after compaction . 4) MOISTURE CONTENT A) When the lime rock does not have the proper moisture content to obtain the required density , wetting or drying will be required . When water is added , it shall be mixed in uniformly . Wetting or drying operations shall involve manipulation of the entire width and depth of the base course before compaction . 5 ) COMPACTION A) The required compaction of the lime rock base course shall be a minimum of 98 percent of the maximum dry density . B) No less than 8- 10 ton steel drum or pneumatic tired roller shall be used to compact the lime rock base course . All depressions shall be filled and the process of rolling and filling shall continue until a thoroughly compacted uniform surface is produced . During final compaction operations , if blading of any area is necessary to obtain the true grade and cross section , the compaction operations for such areas shall be completed prior to making the field density compaction test on the finished base . i C) Should the subgrade material become mixed with the base course material at any time , the Contractor shall remove the mixture , reshape and recompact the subgrade , replace the materials removed with additional lime rock, and reshape and recompact the lime rock base at no cost to the Owner. D) If cracks or checks appear in the base which would impair the structural integrity of the base in the opinion of the Engineer, the Contractor shall remove the cracks or checks by rescarifying , reshaping , refilling with lime rock where necessary , and recompacting at no cost to the Owner. E) The finished lime rock base shall be checked for thickness at intervals of not more than 300 feet. Areas which are less than 1 /2 inch deficient in thickness shall be corrected by scarifying and adding rock if the Engineer determines that the area is extensive or may adversely affect the I RP-2 - 1 ;