Search results for: Free PDF Quiz 2024 High Hit-Rate EMC D-PM-IN-23 Latest Test Report 🍂 Search for ✔ D-PM-IN-23 ️✔️ and download exam materials for free through [ www.pdfvce.com ] 🦞Questions D-PM-IN-23 Exam
-
Simplified analysis of laterally loaded posts
Simplified equations for the strength and deflection of laterally loaded vertical posts embedded in soil foundations, using the modulus of subgrade reaction approach, are presented for simple post embedment and for posts with enlarged footings. Equations describing the elastic behaviour of similarly loaded embedded posts are also detailed. The aim of the paper is to provide a consolidated document containing information for the preliminary design of embedded posts prior to detailed geotechnical investigations and analysis or for the design of such posts where detailed investigations and analysis cannot be justified. The information provided in this paper is not generally available in basic soil mechanics textbooks.
-
Ground improvement in Perth
Much of the city of Perth and surrounding suburbs is situated on an alluvial/aeolian plain and as such is underlain by variable unconsolidated formations. Frequently this limits the application of surface foundations and alternatives are needed. An obvious solution is some form of deep foundation system (piles), however in many cases a cheaper and often more effective solution is found in ground improvement. The most common ground improvement methods applied have been vibrocompaction and/or stone columns and permeation grouting, but other techniques have been applied. This paper presents an historical review of the application of ground improvement in Perth and examines some of the design issues and presents some local applications.
-
Use of probabilistic methods in geotechnical engineering
Due to the intrinsic inhomogeneous nature of soils and rocks, the minimal site investigations, and the need to extrapolate available information over a large domain, geotechnical designs have inevitable uncertainties. To be conservative, geotechnical engineers traditionally use a safety factor to account for uncertainties. A more rigorous way of considering uncertainties is to use probabilistic methods. To promote the use of probabilistic methods in geotechnical engineering, this paper tries to address the following commonly encountered questions:
- Why do we need to use probabilistic methods?
- How can we use probabilistic methods if we don’t have enough test data?
- How much field/test data do we need?
- How can we use multiple sources of information?
- How can we use monitoring data to predict future performance?
-
Discussion on paper by P. Gibbons and S. Cowan (2018) on “Subgrade Treatment design for expansive soils in Adelaide using Australian Standard AS2870 – Is this the right approach?“
The authors have provided a useful case study with a methodology adopted for a particular project, and then raised the broader question of the application of AS 2870 as a correct approach for subgrade treatment. There are many discussions and case studies for AS 2870 with respect to buildings (e.g. Cameron, 2018 in the same AGS volume), but only limited publications with respect to roadways. While AS2870 was developed for buildings, the question on whether the principles and methodology may be applied to roadways is one which requires some discussion and research. This discussion extends nascent questions to the authors and also to other researchers in this area. Gibbons and Cowans (2018) has data based on a “live” project which understandably may not have the benefit of wider data needed for fundamental research type questions posed herein.
-
Settlement characteristics of Coode Island Silt
Coode Island Silt is a Quaternary age alluvial deposit of the Yarra River delta in Melbourne. It is a highly compressible and only slightly overconsolidated deposit, which exhibits significant primary consolidation and creep settlements. This paper discusses the settlement characteristics of this deposit based on laboratory test data and field observations, mostly for a settlement assessment using conventional one dimensional consolidation theory. The rate of creep settlement based on field observations is also discussed.
-
The Challenges Of Field Measurement Of Suction Within Free-standing Mainline Railway Embankments
For over 100 years, adequate performance has been observed for free-standing mainline railway embankments despite the typically rudimentary earthworks techniques used. Notwithstanding this performance, use of effective stress limit equilibrium analyses often do not satisfy the design criteria adopted today. Embankments on the Main Southern Railway are frequently up to 20m high and have been subjected to environmental events; including drought, intense rainfall, flooding on their upslope side and substantial earthquake loading over the last century. In addition, these same embankments can be subjected to the influence of subsidence from underground mining.
One feasible explanation of their adequate performance is the presence of suction within the body of the embankments.
The phenomenon of suction has attracted much study and is thought to be understood by the geotechnical profession. Nevertheless, recognition of suctions within engineering analysis are seldom attempted. What is known as suction can be measured under laboratory conditions and its presence is accepted in the field. However, its measurement in the field, especially at depth, is technically challenging. There is a dearth of research and reported installations of this nature, particularly for embankments and the authors are endeavouring to correct this.The hope is that this paper will stimulate discussion within the geotechnical profession by providing an update on the authors attempts to measure suction at depth in the field with commercially available instruments, and whilst illustrating the challenges faced.
-
Case Studies For Piled Rafts On Clay
Piled rafts have proved to be an effective way of improving the overall performance of a foundation. In the case of structures built on clay, a raft foundation alone may result in excessive settlement. A piled raft foundation is a solution in which the piles provide localised support in heavily loaded regions or areas where deflection is excessive and results in reducing the overall and differential settlements as well as tilting of the foundation. Case histories for piled-rafts foundation on clay will be presented in this paper. The foundations have been studied using a finite layer method for the analysis of a horizontal layered soil and a finite element method for the analysis of the raft and piles. The analysis takes into account the complex soil-structure interactions which govern the behaviour of the piled raft. Case studies of piled rafts on clay will be examined and the results will be compared with the in situ measurements and other numerical results. Comparisons are made in terms of load distribution among piles and the overall and differential settlements.
-
Use of temporary anchors in reinforced soil wall construction for the M4 Motorway widening
The M4 Motorway has in excess of 100,000 vehicle movements per day with the projection exceeding 150,000 vehicle movements per day by 2030. To facilitate the projected traffic flow increase, the M4 Motorway has been upgraded by adding an additional lane in each direction (eastbound and westbound) to the existing three lanes. The upgrade comprises widening a 7.5 kilometre section of motorway between Parramatta and Homebush including the construction of 2 kilometres of viaduct with 49 spans, 3 bridges and 24 retaining walls (including RSWs, soldier pile walls, soil nail walls and reinforced concrete walls).
This paper focuses on the sections of motorway widened using Reinforced Soil Walls (RSW) and presents a case study of the use of temporary Platipus anchors, to retain up to 9 metres of existing engineered fill embankment of the motorway. The construction of the RSWs required excavation of the existing motorway embankment at between 45° to 75° for excavated heights typically between 6 metres and 9 metres. Platipus anchors were selected in preference to soil nail or sheet pile solution to increase the stability of the steep temporary batter, to expedite the excavation process, reduce the amount of excavation of the embankment and reduce the total construction cost. The design considered the stage excavation process and ensured adequate factor of safety at each stage of the excavation process. In addition, the design confirmed that the settlement of the existing M4 pavement immediately adjacent to the excavation was within tolerable limits.
The paper provides discussion on the feasibility assessment of the use of the ‘Platipus’ anchors and the design undertaken for the temporary retention system. It also provides a discussion on the installation process for the anchors, anchor testing undertaken, instrumentation and monitoring; and construction challenges for integration of the temporary support into the permanent works.
-
Ultimate bond stresses from pull out testing of soil nails, Dinnmore to Goodna, South-Eastern Queensland
This paper presents results of pull out tests on soil nails to assess ultimate bond stresses of residual clay soil, alluvium, weathered rock and embankment fill on the Ipswich Motorway Upgrade – Dinmore to Goodna (IMU – D2G) project. Vertical sacrificial soil nails were ‘pulled out’ or loaded to failure in a range of materials to assess bond stresses for design and construction of soil nail walls up to 13 m high. Testing was undertaken in materials for which there are no known published records of bond stress, including alluvium of the Brisbane River bank, historic fill of parts of the former Ipswich Motorway embankment and soil and rock of the Ipswich Coal Measures. This paper aims to share some of the ultimate and mobilised bond stress results obtained on the IMU – D2G project.
-
Ground improvement case studies – Chemical lime piles and dynamic replacement
This paper presents two case studies of soft ground improvement, one involving the use of Chemical Lime Piles for a project in Penang, Malaysia and the other involving the use of Dynamic Replacement in Alexandria in Egypt.
The background and the design approach of each of these ground improvement techniques are presented together with a description of their application in two recent projects. In both cases, field performances are compared with the original designs, and are found to exceed design predictions with respect to strength increase.