Experimental Study On Effect Of Penetrating Characteristicsto Laying Characteristics Of The Coarse Stone

Broadly speaking, coarse stone is a non-sticky coarse grained soil, due toits engineering characteristics,such as higher strength, larger porosity, strongerpermeability, little subsidence deformation and the higher load capacity, notonly undertake the main components of rockfill materials, but also are widelyused in many projects, for example,the rail and road embankment, dam, and thefilter layer of infiltration galleries, has already became an indispensable materialin water conservation project and civil engineering.In the construction, Laying coarse stone are usually to improve the strengthof the foundation, to support the upper member, and to discharg groundwater,thereby reducing the harm of groundwater to the upper structure. Therefore,studying the permeability is a key engineering issue, and the main studiesfocused on water permeability, rather than the impermeability. It will benecessary to solve the problem which makes coarse stone meet designpenetration. Therefore, we should depth study that coarse stone laying haveinfluence on the permeability characteristics.Coarse stone is granular mixtures,which mechanical composed of varyingsizes and diverse properties, due to its different particle sizes, compositiondispersion, greater uniformity coefficient and others complex uncertainties,leading to not do uantitative researchs about the various factors that affectindividual coarse rock permeability. In order to deeply grasp the penetrationcharacteristics of coarse stone, aiming in more engineering applications5mm,20mm,60mm coarse stone as research subjects, through model test andtheoretical analysis, focusing on the coarse particle size, laying thickness, compaction performance,density and pressure head and so on, we conducted a series of studies, the following conclusions have been obtained:1. Through penetration model theory, based on equation of continuity of water infiltration and principles of geometry, initially deduced coarse stone media seepage flow equation: this formula shows that coarse stone media seepage discharge concerned with its porosity, particle size, and laying thickness.2. The internal flow of water in the coarse stone are non-laminar flow state. In the case of artificial loose fill, when d=5mm coarse stone steady infiltrate, flow pattern tends layer flow to turbulent flow, but close to laminar flow; laying thickness increases not affected its flow pattern; If the thickness of a vibrating feeder repeat selected form different density, the bulk density increased impact on larger coarse stone seepage flow pattern, flow pattern transition from becoming more fully turbulent flow. When the bulk density is increased to a value, coarse stone seepage flow pattern may tend to laminar flow; while when d=20mm and d=60mm coarse stone stable infiltration, seepage flow is fully turbulent state, along with the bulk density is increased to a value, coarse stone seepage flow pattern also may tend to laminar flow.3. Using Nonlinear penetration law proposed by Forehheimer, the same penetration path is selected, using the least squares method to determine laminar coefficient a and turbulent coefficient b, thereby determined to average permeability of the working conditions, then receiving three kinds of coarse stone penetration respective law equation J=av+bv2.4. Under the conditions of a single parameter changes, through correlation and regression analysis theory, namely the establishment of a pressure head, diameter, thickness, density and the relationship between the seepage discharge, the seepage flow characteristics and coarse stone laying together. The results show that the greater the pressure head, the larger the particle size of coarse stone, coarse stone seepage is greater, and the greater the thickness, density, thesmaller coarse stone seepage. While using standard regression coefficientregression analysis and Spss software, seepage pressure affect coarse stone head,diameter and thickness were laying degree analysis and found that the impact onthe coarse stone head pressure maximum seepage, coarse Thickness laying stoneparticle impact, followed by a minimum of coarse stone.5. Using the method of dimensional analysis, the establishment of a stableflow seepage flow equation：Q=H52g12；defined as deepage coefficient,which related with head, coarse stone diameter, thickness and density laying andother influencing factors, on this basis, fitting each condition and verify theiraccuracy by f(H)。Results of this study have important reference values to the further studyof coarse stone laying on its permeability characteristics, as well as the practicalapplication of engineering on coarse stone provides a theoretical basis.