文档介绍：岩土工程研究所第六章土压力河海大学岩土工程研究所Research Institute of Geotechnical Engineering, Hohai UniversityChapter 6 Earth Pressure岩土工程研究所第一节概述Introduction?土压力概念What is earth pressure??土压力种类:Types of earth pressure?静止土压力:Earth pressure at rest岩土工程研究所?What is earth pressure?第一节概述IntroductionEarth pressure: The pressure applied on a retaining wall from soil Earth pressure: The pressure applied on a retaining wall from soil 岩土工程研究所第一节概述Introduction主动土压力Active earth pressure被动土压力Passive earth pressure静止土压力Earth pressure at rest?Types of earth pressure?ActivepressureAt-restpressurePassivepressure岩土工程研究所第一节概述Introduction主动土压力Active earth pressure: The wall moves away from the supported soil, and the horizontal soil pressures are refereed to asactive pressure. The soil is in active earth pressure:The wall is caused to move towards the soil being supported,and the horizontal soil pressures are refereed to aspassive pressure. The soil is in passive pressure at rest:The wall is rigid and does not yield, that is there is no movement taking place, the horizontal soil pressures are said to beat-rest pressure. The soil is in at-rest state.?Types of earth pressure?主动极限平衡状态:Active state: plastic equilibrium with lateral expansion taking :Passive state: plastic equilibrium with pression taking : At-rest state: elastic equilibrium with no lateral strain taking natural conditions of deposition, with semi-infinite extent, there is a negligible amount of horizontal strain, the soil is said to be in an at-rest state (or K0 state), and the horizontal effective stress is:Where K0=coefficient of earth pressure at rest . ?At-rest earth pressure?vhK?????002021KHP??The resultant thrust is equal to the area of the pressure distribution diagram, . 岩土工程研究所第二节朗肯土压力理论Rankine’s theory ?Active earth pressure in cohesionless soilsH/3Hpa=rHKaPa=rH2Ka/2Paz???13?aazKztgp?????????)245(23Smooth vertical back, horizontal surf