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
-
Continuous Flight Auger (CFA) Pile Retaining Walls Boundary Settlements During Pile Installation
It is incumbent on developers, designers and contractors to ensure the safety of buildings and occupants on adjacent sites during construction. The critical period on most sites is prior to and during the excavation of the site. This is particularly true on sites where the strata are mainly sands. The use of contiguous and secant pile walls using the continuous flight auger (CFA) method is commonly adopted to provide support to the excavation on such sites. This method can be an economical and, in most cases, effective method. However, there seems to be little cognisance given to the damage caused during installation of the piles by the process sometimes known as “sand mining”. There have been several instances of severe damage to adjacent buildings due to this process not being recognized during the investigation, design and early construction phases. This paper discusses the main causes of settlement during construction and proposes a method to estimate them during the investigation so that the structural engineer can assess their effect on adjacent buildings and services.
-
Pressuremeter Test and Design Applications
Jean-Louis Briaud
-
Application of soil nail wall to roadway widening using GFRP rebars as per Australian design guidelines
This paper presents the application of soil nail wall technology to roadway widening. An arterial road upgrade project in Melbourne consists of widening the freeway in the northern part of Melbourne, including massive cuts into a hillside on the southern side of the existing freeway. Cuts up to 12 meters necessitated the use of retaining walls at 1H:10V batter to stay within the right of way. A soil nail retaining wall was adopted to facilitate reduced excavation, less impact on the existing slope, and improved construction speed with a top-down process. The soil nail retaining wall is 520 m long with a maximum height of approximately 12 meters, including the undercut for pavement and drainage. The ground comprises clay fill overlying residual clay and subsequent weathering profiles of basalt from Newer Volcanics group, partly overlying Brighton Group sediments. Eleven boreholes were drilled sufficiently below the bottom of the wall. Laboratory tests were conducted to estimate the soil and rock strength, including triaxial compression tests with pore pressure measurement to determine effective strength parameters for Brighton group clayey soil. The design employed Glass Fibre Reinforced Polymer (GFRP) bars to enhance the work efficiency by removing encapsulation of steel bars, the durability of which was reviewed for the 100 year design life with the proven data provided by the manufacturer. The soil nail retaining wall was designed as per AS5100.3 and AS4678 guidelines selectively depending on the importance of the wall with reference to VicRoads Specification Section 683 and FHWA-NHI-14-007.
-
2D Numerical Evaluation Of A Vertical Soil Nail Wall
The technique of soil nailing has been increasingly used in stabilization works of slopes and excavations. With this, the use of numerical modelling tools in soil nailing projects is becoming increasingly present in Geotechnical companies. This paper includes a case study of a soil nailing wall instrumented in Concepción city, which consists of an excavation of 15 m height in a residual soil of completely decomposed granitic rock. The numerical model was calibrated, comparing the results of the field instrumentation with the numerical estimates provided by the FEM-RS2 software, based on the two-dimensional finite element method and considering an elastic perfectly plastic model. In this way, the strength reduction factor of the geotechnical structure was obtained, which was compared with the overall factor of safety obtained by limit equilibrium analysis. In addition, through the numerical simulation, it was possible to realize an analysis of the loads on the nails, total displacements of the vertical wall, and compare them with the numerical results. The analysis of the results made it possible to confirm the capacity and usefulness of the FEM-RS2 software in the development and elaboration of soil nailing projects.
-
Monitoring of Sprayed Concrete Lined Tunnels Using Fibre Bragg Grating Sensors
This paper outlines the use of Monitor Optics Systems’ (MOS) Fibre Bragg Grating (FBG) sensor cables for convergence monitoring in tunnels made from sprayed concrete lining (SCL). The Crossrail project is currently installing the new Elizabeth line into the London rail network, and at Farringdon Station, the line will connect to both the London Underground and the Thameslink lines. Due to several of the new tunnels being in close proximity, as well as existing infrastructure and challenging geotechnical conditions, the decision was made to monitor the critical “RTE2” tunnel to ensure it was performing as designed. Pressure sensors and survey prisms were initially selected to monitor the tunnel’s critical locations. However, as pressure sensors had a reputation for unreliable results due to difficulties with their installation, an additional method was sought out to validate the pressure and surveyed results. Following their successful use in a tunnel at Bond Street Station, MOS sensor cables were selected to monitor the tunnel in conjunction with the pressure sensors and survey prisms.
MOS sensor cables that incorporate a nylon coating are designed to survive direct embedment into the SCL of a tunnel and can provide real time monitoring of the lining immediately after embedment. Sensor cables with five FBGs were installed at two locations in the RTE2 tunnel, along with corresponding temperature sensor cables. The FBGs were monitored using an optical interrogator located outside of the installation area through the use of fibre optic signal cables. Data was available for visualisation and manipulation through the MOS web hosting site DaMiNs.
FBGs, survey prisms, and pressure sensors were located at the same locations, and the FBG results generally showed good agreement with the surveyed results. The majority of the pressure sensors were unable to capture reliable results but were also in good agreement with the FBG results where reliable data was captured. The monitoring results validated the tunnel design and allowed additional tunnel construction to continue without additional unnecessary concrete linings.
-
Design And Monitoring Of Landfill Cover Systems
Monitoring of the percolation through previously constructed capping layers at a former landfill at Bacton Road, Chandler was carried out to assess their performance under Brisbane climatic conditions. Comparisons of the field percolation with the results of modelling using the SoilCover finite element program were made, leading to the development of a simplified cap design. Construction of the simplified cap was carried out at a second landfill at Roghan Road, Fitzgibbon and subsequent monitoring confirmed its modelled performance agreed with the field data. Percolation rates were found to be significantly below those determined from conventional water balance models and indicate a simple single or double layer cap will perform adequately in Brisbane’s sub-tropical climate.
-
The State of Engineering Geology Education in Australia
Introduction – what does an engineering geologist need to know?
This editorial is about the education of engineering geology in Australia, or perhaps more pertinently the lack of it. It discusses how we currently educate engineering geologists in Australia, the lack of practitioners in our industry who arrive through a geoscience education pathway, how we can meet our skills demand in engineering geology through better education and what the barriers are to improving the current situation.
Before discussing the state of engineering geology education in Australia, it is first necessary to establish what an engineering geologist does and what knowledge and skills our education system needs to impart to them – a simple question with many answers if one is to look hard enough into the literature. But let’s go with a 1962 quote from one of the founders of Engineering Geology in Australia, Daniel Moye (see cover photo) which encapsulates it nicely:
Engineering geology in practice is a service to civil engineering (including the civil aspects of mining engineering). The engineering geologist should be, first and foremost, a well-trained geologist. However, there are very few engineers qualified to specify in detail the nature of the geological services they require. So to be fully effective, the engineering geologist should have sufficient insight into the nature of engineering problems to be able on the one hand to recognise and select for investigation the geological factors which are significant to particular engineering projects, and, on the other hand, to avoid wasted effort on irrelevant aspects of geology. Further, he should be able to communicate the geological information for the engineer in terms which can be understood and used, otherwise his work is sterile.
It is considered therefore that the systematic study of engineering geology should be deferred until the student has the required background in geology, i.e. after a 3-year course.
– Daniel George Moye, 1962
Ignoring the 1962 gender references (we have come a long way), according to this definition, we could say that Engineering Geology is rooted in geological science or geoscience, but it is a science that helps solve engineering problems. One might infer from this that the skills of the engineering geologist transcend the realms of both science and engineering, and so one educated as an engineering geologist might require skills in both the fields of engineering and science. That’s the premise with which we will approach this review of Australian education in engineering geology. We’ll return to the part of the quote about studying engineering geology after a three year geology course.
The Australian Geomechanics Society is one of the few geotechnical societies in the world that brings together engineering geology, soil mechanics and rock mechanics under one association, by being the Australian member society of the IAEG, ISSMGE and ISRM. This is done under the all encompassing term of ‘geomechanics’. It is debatable as to whether ‘geomechanics’ is an appropriate term to encompass all these disciplines. Perhaps ‘ground engineering’, or ‘geotechnics’ could be alternative terms, but to be consistent with the name of our society, I’ll adopt the term geomechanics in this editorial as an overarching term that encompasses all the knowledge and skills needed to understand and control ground response to human activities. However, substitute whichever term you prefer.
The importance of geoscience to geomechanics has been recognised since the dawn of the profession. If Karl Terzaghi was the father of soil mechanics, let’s not forget that his wife, Ruth was an eminent geologist and one of the early engineering geologists. Perhaps that makes her the mother of modern engineering geology. However, the criticality of the union between geotechnical engineering and geology has long been recognised.
The geotechnical engineer should apply theory and experimentation but temper them by putting them into the context of the uncertainty of nature. Judgement enters through engineering geology.
– Karl Terzaghi
John Burland recognised that geomechanics broadly requires 3 key inputs, being knowledge of the ground profile, knowledge of material behaviour and an appropriate model, as set out in his famous Geotechnical Triangle (Figure 1) with ‘ground profile’ which would seem to lie firmly in the realm of engineering geology and which occupies a prominent corner of the triangle. This implies that without some knowledge of the ground profile, geomechanics (Burland uses the term geotechnical), cannot happen. With reference to the geotechnical triangle, whilst the geological sciences are important for establishing the ground profile, it can be strongly argued that they are also necessary inputs to the other corners of the triangle. For example, to understand material behaviour, a knowledge of past ground behaviour is vital, and developing an appropriate model requires geoscience as discussed in the recently published IAEG guidelines for engineering geological models (Baynes and Parry 2022, see synopsis in this volume). The geosciences are a necessary input to all parts of the geotechnical triangle and so vital for geomechanics.
Brunsden in his 2002 Glossop lecture used the term ‘Core Geo Team’ to represent all the skills required for geomechanics, breaking those skills down into 4 broad categories; soil mechanics, rock mechanics, engineering geology and engineering geomorphology (Figure 2). He notes that these skills are all vital inputs into civil engineering, and notably to all stages of civil engineering from planning to decommissioning.
-
AGS NSW Research Award 2016
for Research in Geotechnical Engineering or Engineering Geology PresentationsDanielle Griffani, Lam Dinh Nguyen and Sinniah Navaratnarajah