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
-
Application Of Clegg Impact Value For The Evaluation Of The Properties Of Asphalt Concrete
The Clegg impact hammer is used to obtain a parameter relating to strength or stiffness of soil or similar type of materials. The parameter obtained is called the Clegg impact value (CIV). This study has investigated the relationship between CIV and bitumen content in a compacted bituminous concrete and the possible application of CIV for the evaluation of the properties of asphalt concrete. It was found that the CIV of compacted asphalt increases to a maximum value and then decreases with an increase in bitumen content. This relationship was similar to the stability versus bitumen content relationship determined in the Marshall method of mix design. Optimum binder contents determined using CIV, air voids and bulk density were comparable with those values determined using the standard Marshall method and the Austroads Pavement Research Group method.
-
Geology of Melbourne Course 2021 (2nd edition)
Darren Paul, Chris Coulson
-
Urban salinity site investigations for greenfield developments
Salinity is an issue that was first reported in 1924 (Wood, 1924) but is only now becoming increasingly recognised as affecting urban areas and infrastructure. It is also increasingly recognised that urban development and management of urban areas can alter salinity processes so that the impacts on development vary not only spatially but also temporally.
The NSW Department of Infrastructure, Planning and Natural Resources (DIPNR) published a framework methodology for urban salinity site investigations in late 2002 (Lillicrap and McGhie, 2002). The report outlined 4 phases to an investigation:
- detailed desktop review of the site and general vicinity as well as initial site walk over and field testing
- groundwater and soil sample analysis to ensure a thorough understanding of the salinity processes, how they might affect the proposed development and how the development may impact on the processes
- interpretation of results and comparison to standards suitable for urban development and
- promotion of site specific and development specific management recommendations.
Each stage relies on information from previous stages to inform the decision process. Undertaking the investigations as early as possible in the development process, for example at rezoning, provides more opportunities to manage salinity effectively and efficiently.
Over the last 4 years there has been an increasing number of urban salinity site investigations, most of which are based loosely on this methodology. Steps 3 and 4 however are often problematic, as urban salinity is such a new area of expertise. For example, soil scientists experienced in investigating soils for erosion hazard, contamination, load bearing properties, shrink swell characteristics or perhaps rural salinity are being asked to comment on the immediate and longterm impacts of types and amounts of salts on bricks, mortar and cement.
The CSIRO worked with the Hawkesbury-Nepean Catchment Management Authority and DIPNR to look at the range of tests commonly performed for urban development in order to determine whether these could be used for urban salinity investigations. Key findings from this work will be presented in this paper along with other experiences from development in western Sydney.
-
A Useful Tool For Earthworks Control – The Dilatometer
This paper briefly discusses and promotes the use of the in situ Flat Dilatometer test (DMT) for at least some earthworks control. The paper is meant to provoke thought, as follows:
- Geotechnical design is most often based on two parameters, soil strength and modulus. Yet these two parameters are seldom specified or measured as part of earthworks contracts.
- The author holds the view that the main reason for this is “history”. Practical methods were not available in the past to directly measure strength and modulus in the field.
- Advances in in situ testing technology make such measurements possible today.
- Why not, where relevant, include these design-required parameters within earthworks specifications, and why not measure them and make achievement of them part of the earthworks acceptance process?
One, now available, tool that can defensibly measure both strength and modulus and is robust and simple to use, is discussed within this paper, the Flat Dilatometer.
-
A New Calculation Approach To Design Flexible Facing System For Soil Nailing
According to the experience of several researchers, under certain conditions the soil nailing facing system can be developed with nails in cooperation with steel mesh (i.e. flexible structural facing). The goal of this system is to improve the slope face stability and allow the vegetation to grow. A simple design approach was introduced a few years ago that analysed the behaviour of the mesh by comparing the maximum volume of debris that can move among the nails to the maximum volume that can be held by the mesh. Even if it took into account the real interaction between mesh and soil, such procedure was quite rudimental by solving the non-linearity of the load-displacement problem. Recently, a new design approach using forces generated by the soil pushing on the mesh was proposed considering the most unfavourable case between the two wedge analysis and the single wedge, one for slope failure mode (according to the standard BS 1006 – 2010). Concerning the mesh resistance, the new approach overcomes the non-linearity of the problem and allows a more realistic calculation approach. This has been feasible thanks to the interpretation of the load-displacement curves generated in accordance to the UNI 11437 (2012) Standard as well as to the introduction of the “scale effect” that modifies the nail spacing and mesh behaviour accordingly.
For sure the methodology is not perfect, but at least it allows appreciating the Ultimate Limit State and the Serviceability Limit State with a simple calculation. This paper analyses the main calculation steps and concepts of this new approach implemented in the new Bios 2 software which is used by Maccaferri for the design of flexible facing of cut and natural slopes.
-
Point-load testing chips of rock
Hole production in the mining and petroleum industries produces chips of rock ranging in size from a few mm up to approximately 15 mm. Chips have however generally been considered too small for strength testing. The current research has shown that it may be possible to obtain the strength of chips from well-sorted, homogeneous, rocks, having fine to medium particle size, when tested perpendicular to discontinuities, using a standard point load test apparatus with modified platens. The modification only requires the 5 mm ball bearings on the tips of the platens to be replaced with 1 mm ball bearings. More research is however required to validate the result.
-
The Use of Ultra-Wide Band GPR for the Detection of Voiding and Other Artefacts in Bridge Abutments and Related Retaining Structures
The structural integrity of bridge abutments and retaining structures can be compromised by the presence of voids. Structural deformations visible on the surface of structures that are indicative of voiding may not indicate the actual location of voids within the structure, therefore, pinpointing problem areas can be problematic. Traditional destructive methods of investigating these structures (including drilling and borescope inspection) generally only provide limited information at a single point; they also have the potential to cause damage to the structure during investigation.. Standard GPR (Ground Penetrating Radar) methods are utilised as a supplement and/or alternative to traditional methods of investigation but have limitation of depth and resolution. Ultra-wide band GPR methods provide an efficient non-destructive method for the detection of voiding while maintaining resolution over a broader depth range than that of other GPR methods.
Most GPR devices use an antenna that has a discrete peak frequency which provides a resolution at a specific depth. To investigate different depths, several different GPR antennae must be utilised with varying peak frequencies. As these antennae only have a peak frequency, resolution falls at depths which are outside of the specific depth related to the peak frequency of the respective antennae. Ultra-wide band GPR differs from standard GPR devices by having a range of peak frequencies that enable it to maintain the resolution over a broader depth range.
This paper provides a discussion on the feasibility of ultra-wide band GPR as a tool to investigate voiding of bridge abutments and retaining structures. It also provides a description of the methodology utilised for the assessment of ultra-wide band GPR technology and a description of its potential suitability for other uses.
-
Full scale testing of ground remediation options for residential property repair following the Canterbury earthquakes
A series of full scale tests have been undertaken to assess the performance of ground strengthening methods to improve seismic performance of liquefiable soils in the Christchurch area. The tests used sequences of explosive charges to simulate seismic shaking at levels representative of SLS and ULS events and induced liquefaction and expulsion of sand. Monitoring included measurement of ground motion, pore pressure development and settlements.
The results have determined that the treatment of the upper crust by densification or cement stabilisation is an effective method of reducing settlements and preventing surface expulsion of liquefiable soil. Other options including deep soil mixing and a perimeter curtain wall were less effective but achieved the proposed design objectives and also have application.
-
Influence Of Soil Characteristics On Seismic Response Of Mid-rise Moment Resisting Buildings Considering Soil-Structure Interaction
In this study, a fifteen storey moment resisting building frame, representing the conventional types of regular mid-rise building frames, resting on a shallow foundation, is selected in conjunction with three soil types with the shear wave velocity less that 600m/s, representing classes Ce, De and Ee, according to AS 1170.4. Characteristics of the employed soils have been extracted from the available geotechnical investigation reports of various projects. Furthermore, the structure is modelled considering the three mentioned types of the subsoil medium underneath employing the Finite Difference approach using FLAC 2D software. Three strong ground motion records adopted by the international community as benchmark earthquakes are used. These are the 1968 Hachinohe, the 1995 Kobe and the 1994 Northridge earthquakes. Fully nonlinear dynamic analysis under influence of different earthquake records is conducted, and the results of the three different cases are compared and discussed. The results indicate that the dynamic properties of the subsoil play a significant role in seismic response of the building frames under the influence of soil-structure interaction. As the shear wave velocity of the subsoil decreases, lateral deflections and inter-storey drifts of the structures increase which can change the performance level of the structures from life safe to near collapse or total collapse.