scholarly journals Optimizing Basement Construction Methods

2021 ◽  
Vol 1 (3) ◽  
pp. 51-61
Author(s):  
Nguyen Huu Bao
Keyword(s):  
Retaining Walls ◽  
Diaphragm Wall ◽  
Construction Work ◽  
Underground Part ◽  
Construction Costs ◽  
Deep Foundation ◽  
Construction Methods ◽  
Technical Requirements ◽  
Floor Structure ◽  
Ground Stability

The underground part of SSG TOWER includes 4 basements, 4 basements at a height of -13.2m. Combined with the construction of 3m deep foundation, therefore, the minimum excavation depth is required to -16.2m. Due to the construction work in residential area, relatively ground, with large excavation depth and geology of the interaction area (clay layer up to 30m), the options for using diaphragm wall with drilled piles Small area, Laser piles or solier piles to make retaining walls during construction do not have that feature, so the author chooses the option of using reinforced concrete barrette walls for retaining walls during construction and as tunnel walls for this project. The semi-topdown construction method was chosen to ensure safety during construction because the excavation depth of the work is quite large and the geology of this area is quite weak. This measure completely solves the strut system because using the floor structure of the building to support this system has high stability. Limiting the influence of settlement, cracking, and slippage to neighboring works a lot. Fast construction but in return for high technical requirements, high construction costs. Choose diaphragm wall thickness of 1.0m, base depth of 46.6m including standard barrete panels.  The author uses 2D Plaxis simulation to calculate ground stability, stress and displacement, moment, and shear force generated in diaphragm wall during basement construction. The author analyzes using the optimization algorithm to compare and find the suitable solution.

Deformation and Internal Force Analysis of Deep Foundation Pit Excavation with Outrigger-Type Diaphragm Wall

2011 ◽  
Vol 250-253 ◽  
pp. 1983-1987
Author(s):  
An Feng Hu ◽  
Hang Rao ◽  
Jing Yuan
Keyword(s):  
Cross Section ◽  
Variable Cross Section ◽  
Internal Force ◽  
Diaphragm Wall ◽  
Variable Cross ◽  
Deep Foundation ◽  
Supporting Structure ◽  
Technical Requirements ◽  
Deep Pit ◽  
Modified Cam Clay

As a new technique of excavation support structures, outrigger-type diaphragm wall has got an application in deep pit engineering, though the design of its parameters still lacks theoretical guidance. Based on a large-scale deep pit case, a 3-D finite element model is presented to simulate the behavior of outrigger-type diaphragm wall using the software ABAQUS. The soil is assumed to behave as a modified Cam-clay model. The effect of the outrigger length on deformation and internal force of the supporting structure is studied. It is found that the basal heave ,the ground settlement and the horizontal displacements of the retaining wall will increase with the increase of the outrigger length, when the bottom elevation of the supporting structure keeps unchanged. When the outrigger length goes beyond a certain length, the rate of increasing becomes larger. In the outrigger-type diaphragm wall, the vertical stress of inside and outside wall approaches the maximum in the vicinity of the variable cross-section. At the same time, the variable cross-section produces a shear stress mutation because of the abrupt change of stiffness. There exists a reasonable length of the outrigger, which could meet not only the technical requirements of the supporting structure, but also the needs of saving the cost and reducing the difficulty during the construction.

Two-Dimensional Numerical Simulation Analysis of the Diaphragm Wall Earth Pressure and Deformation Used the Cover Reverse Construction Excavation Method

2011 ◽  
Vol 243-249 ◽  
pp. 2732-2737
Author(s):  
Hong Bo Guo ◽  
Ke Sheng Ding ◽  
Yi Jia Zhang ◽  
Xu Li
Keyword(s):  
Simulation Analysis ◽  
Soft Soil ◽  
Constitutive Models ◽  
Earth Pressure ◽  
Diaphragm Wall ◽  
Deep Foundation ◽  
Construction Methods ◽  
The Earth ◽  
Test Parameters ◽  
Practical Engineering

The cover reverse construction excavation is one of the important construction methods which is used in digging extra-deep foundation system of underground continuous wall supporting. The earth pressure distribution and deformation is distinct from different construction methods. Even if the Construction methods and computer program is homogeneous, the earth pressure and deformation of the calculated showed various results because of different test parameters and different constitutive models, Through the application of practical engineering, The appropriate calculation parameters and constitutive model are found out in Abaqus program which is suitable for earth pressure and deformation of the diaphragm wall in the soft soil area.

scholarly journals The Interaction Features of the Multi-Level Retaining Walls with Soil Mass

2017 ◽  
Vol 26 (3) ◽  
pp. 179-190
Author(s):  
Igor Boyko ◽  
Liudmyla Skochko ◽  
Veronica Zhuk
Keyword(s):  
Numerical Modelling ◽  
Numerical Simulations ◽  
Variable Stiffness ◽  
Retaining Walls ◽  
Soil Mass ◽  
Soil Base ◽  
Deep Foundation ◽  
Multi Level ◽  
Horizontal Displacements

Abstract The interaction features of multi-level retaining walls with soil base were researched by changing their geometric parameters and locality at the plan. During excavation of deep foundation pits it is important to choose the type of constructions which influences on the horizontal displacements. The distance between the levels of retaining walls should be based on the results of numerical modelling. The objective of this paper is to present a comparison between the data of numerical simulations and the results of the in-situ lateral tests of couple piles. The problems have been solved by using the following soil models: Coulomb-Mohr model; model, which is based on the dilatation theory; elastic-plastic model with variable stiffness parameters.

Optimum Design of Reinforced Concrete Retaining Walls

2018 ◽  
pp. 360-378
Author(s):  
Rasim Temür ◽  
Gebrail Bekdaş
Keyword(s):  
Reinforced Concrete ◽  
Optimum Design ◽  
Search Algorithm ◽  
Harmony Search ◽  
Minimum Cost ◽  
Retaining Walls ◽  
Slab Thickness ◽  
Construction Costs ◽  
Design Variables ◽  
Cantilever Retaining Walls

Methodologies based on metaheuristic algorithms such as particle swarm optimization, harmony search algorithm, and teaching-learning-based optimization are proposed for optimum design of reinforced concrete cantilever retaining walls. The objective function of optimization is to find a design providing minimum cost, including material and construction costs. For this purpose, the best combination of 11 design variables (heel and toe projections, stem thickness at the top and bottom of a wall, slab thickness and rebar diameters, and spacing between the bars) that satisfy 29 design constraints including stability (overturning, sliding, and bearing) and reinforced concrete design of the wall are searched during the optimization process. The rules of ACI 318 14 (building code requirements for structural concrete) are used for the reinforced concrete design. In order to determine the strengths and weaknesses of algorithms, several different cases are investigated. As conclusions, some suggestions have been obtained that will lead to future work in this field.

scholarly journals Study on Foundation Pit Construction Cost Prediction Based on the Stacked Denoising Autoencoder

2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Lanjun Liu ◽  
Denghui Liu ◽  
Han Wu ◽  
Junwu Wang
Keyword(s):  
Influencing Factors ◽  
Construction Cost ◽  
Average Error ◽  
Support Vector ◽  
Calculation Error ◽  
Denoising Autoencoder ◽  
Construction Costs ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Project Construction

To accurately predict the construction costs of foundation pit projects, a model based on the stacked denoising autoencoder (SDAE) is constructed in this work. The influencing factors of foundation pit project construction costs are identified from the four attributes of construction cost management, namely, engineering, the environment, the market, and management. Combined with Chinese national standards and the practice of foundation pit project management, a method of the quantization of the influencing factors is presented. 60 deep foundation pit projects in China are selected to obtain 13 main characteristic factors affecting these project construction cost by using the rough set. Then, considering the advantages of the SDAE in dealing with complex nonlinear problems, a prediction model of foundation pit project construction costs is created. Finally, this paper employs these 60 projects for a case analysis. The case study demonstrates that, compared with the actual construction costs, the calculation error of the proposed method is less than 3%, and the average error is only 1.54%. In addition, three error analysis tools commonly used in machine learning (the determination coefficient, root mean square error, and mean absolute error) emphasize that the calculation accuracy of the proposed method is notably higher than those of other methods (Chinese national code, the multivariate return method, the BP algorithm, the BP model optimized by the genetic algorithm, the support vector machine, and the RBF model). The relevant research results of this paper provide a useful reference for the prediction of the construction costs of foundation pit projects.

scholarly journals Exploring the Components of Cost on Construction Projects

2018 ◽  
Vol 2 (2) ◽  
pp. 42-50
Author(s):  
Abimbola Windapo ◽  
Alireza Moghayedi ◽  
David Oliphant ◽  
AbdulRauf Adediran
Keyword(s):  
South Africa ◽  
Construction Projects ◽  
Resource Planning ◽  
Construction Cost ◽  
Research Approach ◽  
Construction Work ◽  
Construction Costs ◽  
Cost Overruns ◽  
Planning And Control ◽  
Electrical Installation

This study examines the components of construction projects and whether there are construction resources that are the key project constituents. The rationale for the study stems from the unexplained assumptions regarding the primary components responsible for increases in construction costs in South Africa, as South Africa lacks a national building cost database. The study adopts a qualitative research approach that employs a case studies of six new and six refurbished projects in obtaining the necessary data for use in answering the study objectives. The study found that the primary cost constituents of construction projects are materials and sub-contracted work, accounting for 63.69% and 74.6% of the value of renovation and new construction work respectively and on the average, the major materials by value are reinforcement, cement and filling, while Electrical Installation is the primary sub-contracting item by value. Based on these findings, the study concludes that the future levels of construction work can be predicted knowing levels of specialist sub-contractor costs and building material costs. The study recommends that the sub-contractor and material inputs into construction projects are carefully managed, both on the projects and the construction industry, to limit construction cost increases and cost overruns on projects. The study contributes to the literature on resource planning and control in construction. Keywords: Cement, Construction Cost, Electrical Installation, Reinforcement, Specialist Sub-contractor.

scholarly journals Comparative Analysis of Plate Girder Designs In The Composite Bridge Between AASHTO LRFD Bridge Design Specifications 2017 Regulation with SNI 1729: 2015

2019 ◽  
Vol 1 (1) ◽  
pp. 24-39
Author(s):  
Donald Essen ◽  
Ryza Nur Rohman
Keyword(s):  
Construction Materials ◽  
Internal Force ◽  
Construction Work ◽  
Bridge Design ◽  
Design Specifications ◽  
Construction Methods ◽  
Composite Girder ◽  
Materials Used ◽  
Plate Composite Girder ◽  
Aashto Lrfd

In the world of construction there are various methods and types of materials used to support the passage of a construction work. One of them is composite girder plate. Composite girder plate is one of the many construction methods that combine two construction materials that are physically different in nature, namely concrete with steel. This type of composite girder plate construction is commonly used for bridge construction work with a fairly large span and width. In its use, of course, it must be preceded by stages of careful planning on a standard and valid basis as well. In the following research will discuss and look for similarities and differences regarding the two types of rules in the planning of composite girder plates, namely the rules of planning composite girder plates using AASHTO LRFD BRIDGE DESIGN SPECIFICATIONS 2017 with SNI 1729: 2015. After doing the initial stages of modeling using CSI Bridge software using the profile cross section constraints of the AASHTO provisions, the internal force obtained is Moment Force (Mu) of 3469.13 kNm and Shear Force (Vu) of 225.98 kNm. Then proceed with the analysis of calculations with the help of Microsoft Excel software namely calculating using the AASHTO LRFD BRIDGE DESIGN SPECIFICATIONS 2017 regulations for stability requirements of strong boundary conditions on the bending requirements. Then a Nominal Moment (ØMn) value of 6420.19 kNm is obtained. Then proceed to calculate the same planning constraints, but this time using SNI 1729: 2015 regulations. Obtained Nominal Moment Value (ØMn) of 6579.88 kNm. Then it can be concluded that the two regulations produce a safe and strong planning, of course in accordance with applicable regulations namely: Moment (Mu <ØMn).

Sign in / Sign up

Export Citation Format

Share Document