Study On Modification Of Roadbed Filler With Oil - Based Cuttings

Shale gas reserves ranking the world's first in China,and its development is the precondition of ecological environment protection,shale gas resources in the mining process can produce a large number of oil-base cuttings,only kei igawa oil drilling coMPany in each year in changning and hubei vying areas will produce about 20000m~3 of waiting to be processed oil-based cuttings,if put in one place will directly cause damage to the ecological environment,it will hinder the development of the industry.In this paper,the treated oil-based cuttings are mixed into the wellsite filler for use in the pre-drilling engineering or the low-grade roadbed,so that it can not only meet the technical indexes and roadbed performance requirements,but also meet the national environmental protection standards.By means of laboratory test and theoretical analysis,the mix design and road-use performance of oil-base rock cuttings mixed into the roadbed filler are studied.Through a series of laboratory tests,the basic properties of subgrade fillers were tested.The chemical composition and leaching toxicity of oil-based cuttings were determined,the possible iMPact on the environment was analyzed and evaluated,and the feasibility of incorporation of roadbed fillers into the wellsite was investigated.Five groups of oil-base cuttings roadbed fillers with different mass ratios were prepared,and the ability of each ratio to resist shear deformation under different water content was tested.Combined with five piece together than the test result,carries on the experimental study of subgrade filling modified cement containing oil-base cuttings,designs three groups of different cement dosage adding to oil-based debris subgrade filling in the experiment,the different cement dosage on the properties of subgrade filling containing oil-based cutting various aspects,to determine the best dose of cement,determine the final oil-based cuttings with wellsite roadbed stuffing mix scheme.Main research contents and achievements are as follows:(1)It is feasible to construct a new resource-based roadbed filler by adding oil-based cuttings treated by LRET technology into roadbed filler near the wellsite according to a certain mass ratio.(2)The oil-based cuttings added to the original packing will make the packing of liquid plastic limit wl and wp and plasticity index Ip appear to change,but the liquid plastic limit wl and wp and plasticity index change by Ip range is not too big,oil-based cutting quality than increase did not keep the original packing of the coMPaction property does not appear particularly big changes,with the increase of oil-based cutting quality than the trend of the CBR value increase with the decrease of the first,oil-based cutting quality than the increase of unconfined compressive strength of the specimens showed a trend of decrease after the first increase.(3)Will be taken by a certain mass ratio of oil-based cutting and adding filler,can make the nature of the filler improved,recommends to 10%~20%in the practical application of oil-based cutting quality than advisable,if consider including oil-based debris subgrade filling ratio of maximum processing,we suggest 20%mass ratio of oil-base cuttings,namely:the recommended optimization matching m(oil-base cuttings):m(subgrade filling)=0were.(4)When the oil-based cutting quality is between 5%~25%,the moisture content is controlled between 6%~15%to 2%of the moisture content is gradually increased,the mass ratio of filler in the Angle of internal friction curves under different moisture content does not appear relatively regular change curve,but the overall trend of the curve is as the moisture content of gradually increase the Angle of internal friction in the reduced;When the water content of O5 and O15 gradually increased,the trend of the cohesion curve was first up and then down.When the water content of O10,O20 and O25 gradually increased,there was no regular change in the cohesion curve.(5)By comprehensive coMParison,the ability to resist shear deformation when the water content of O5,O10,O15,O20 and O25 changes is enhanced coMPared with that of the original filler.(6)With the addition of cement,the compressive strength of the O25 test group was significantly improved coMPared with that of CBR.(7)In the comprehensive economic and applicability factors,when the cement modified O25test group contains oil-base cuttings roadbed filler,the cement content is optimized by4%~6%,the secondary choice is 2%~4%,and the final choice is 0%~2%(except 0%).The optimal mass ratio is recommended to be m(cement):m(oil-base cuttings):m(roadbed filler)=4:25:75.