Detail of JGJ 167-2009

Introduction of JGJ 167-2009

1 General Provisions 1.0.1 With view to ensuring the safety and applicability of building foundation excavation engineering in collapsible loess regions in each link and realizing technical advancement, economic rationality and environmental protection, the Specifications is formulated. 1.0.2 The Specifications is applicable to the technical safety and management for investigation, design, construction, detection and monitoring of building foundation excavation engineering in collapsible loess regions. 1.0.3 For building excavation engineering, foundation pit as well as the engineering geological and hydrogeological conditions within certain range around the foundation pit, excavation concentration, surrounding environment, foundation pit importance, possibility of soaked by water, construction conditions, service life of retaining and protecting structure and the like shall be taken into comprehensive consideration. Meanwhile, the elaborate design, rational layout, strict construction and effective supervision shall be realized by way of combination with engineering experience. 1.0.4 In addition to the requirements of the Specifications, building foundation excavation engineering in collapsible loess regions shall also comply with those stipulated in the current relevant standards of the nation. 2 Terms and Symbols 2.1 Terms 2.1.1 collapsible loess the loess of which the soil structure is rapidly damaged and visibly collapsed after being soaked by water under pressure 2.1.2 building foundation pit the space below the ground (including foundation trench) that is excavated for carrying out building (including structure and building) foundation and basement construction 2.1.3 foundation pit wall certain side that is a part of foundation pit enclosure 2.1.4 surroundings foundation pit; surroundings around foundation pit a general term of those including existing building (structure), road, underground facility, underground pipeline, rock-soil mass and underground water within the influence region of pit excavation 2.1.5 retaining and protecting for foundation excavation the retaining, reinforcement and protective measures adopted for foundation pit wall and surroundings for the purpose of ensuring the safety of underground structure construction and surroundings around foundation pit 2.1.6 slope ratio method the pit excavation construction method without the use of retaining and protection measures, which maintains the stability of foundation pit wall through the strength of soil mass after step-slope at reasonable slope grade 2.1.7 soil-nailed wall the retaining and protecting structure composed of foundation pit wall reinforced with soil nail and protective covering, etc. 2.1.8 cement-soil wall the gravity retaining and protecting structure in types of grilling or wall, which is mutually overlapped by soil-cement piles 2.1.9 soldier piles the retaining and protecting structure for foundation excavation, which is composed of certain pile type in queue 2.1.10 ground anchor the tension member composed of grouting in hole and the steel bar or steel strand that is arranged in drill hole and whose end is stretched into stabilized soil layer 2.1.11 top beam the reinforced concrete connecting beam or steel connecting beam arranged at the top of retaining and protecting structure 2.1.12 waist beam the reinforced concrete beam or steel beam that is arranged below the top of retaining and protecting structure and transfers bearing point force of retaining and protecting structure, anchor rod or inner support 2.1.13 bearing point the horizontal constraint point of anchor rod or support system to retaining and protecting structure 2.1.14 stiffness of fulcrum bearing the ratio between horizontal reactive force of anchor rod or support system to retaining and protecting structure and its corresponding displacement 2.1.15 embedded depth the embedded depth of piling wall structure below the base of pit excavation 2.1.16 cut-off curtain the continuous waterstops adopted for stopping or reducing the seepage of ground water around foundation pit or bottom ground water into foundation pit 2.1.17 area of protection the area within the protection distance around the foundation pit 2.1.18 information feed back construction method the construction method in which geological conclusions and design parameters are verified, construction safety is determined and construction scheme is timely corrected on the basis of the geological condition and monitoring data on the construction site

Contents of JGJ 167-2009

1 General Provisions 2 Terms and Symbols 2.1 Terms 2.2 Symbols 3 Basic Requirements 3.1 Design Principle 3.2 Construction Requirements 3.3 Horizontal Load 3.4 Passive soil pressure 4 Foundation Excavation Engineering Investigation 4.1 General Requirements 4.2 Investigation Requirements 4.3 Investment Result 5 Slope Ratio Method 5.1 General Requirements 5.2 Design 5.3 Construction Requirements 5.4 Construction 6 Soil-nailed Wall 6.1 General Requirements 6.2 Design Calculation 6.3 Structure 6.4 Construction and Detection 7 Cement-soil Wall 7.1 General Requirements 7.2 Design 7.3 Construction 7.4 Quality Inspection and Monitoring 8 Soldier Piles 8.1 General Requirements 8.2 Embedded Depth and Bearing Point Force Calculation 8.3 Structural Calculation 8.4 Bearing Capacity Calculation of Soldier Pile Section 8.5 Anchor Rod Calculation 8.6 Construction and Inspection 9 Dewatering and Earthworks 9.1 General Requirements 9.2 Pipe Well Dewatering 9.3 Earthwork Excavation 9.4 Earthwork Backfilling 10 Foundation Trench Engineering 10.1 General Requirements 10.2 Design 10.3 Construction, Backfilling and Inspection 11 Environmental Protection and Monitoring 11.1 General Requirements 11.2 Environmental Protection 11.3 Monitoring 12 Acceptance for Foundation Excavation 12.1 General Requirements 12.2 Acceptance Content 12.3 Acceptance Procedure and Organization 13 Safety Use and Maintenance of Building Excavation Engineering 13.1 General Requirements 13.2 Safety Measures 13.3 Safety Control Annex A Circular Slip Simple Slice Method Annex B Cement Soil Mix Proportion Test Annex C Calculation Formulae for the Internal Force and Deflection of Cantilever Beam Annex D Calculation for Water Discharge in Foundation Pit Wording Explanation of the Specifications