Important Info

Featured Sponsor

Become an Author

GeoPrac.net is a community site, we are only as good as the content our members contribute! Whether it's a one time contribution, or a monthly or quarterly article, please consider becoming an author!

Latest Comments in...

Recording Geotechnical Drill Rig Parameters
Thanks, for the insight, Howard. I think you're probably right about the "t
Recording Geotechnical Drill Rig Parameters
This type of data recording is old hat in the oil & gas drilling biz (for e
Engineering Geologists vs Geological Engineers vs Geotechnic
what is the clear cut difference between engineering geologist and Geologic
Sinkhole Beneath National Corvette Museum Devours 8 Cars
This is my worst nightmare! Being trapped in your car while you and other c
Content
Available Resources
Roadheaders in North America PDF Print E-mail
Written by Randy Post   
Monday, 05 September 2011 15:21

Roadheader

Drill and Blast and Tunnel Boring Machine are two common types of tunnel construction methods. But roadheaders have been around for many years, getting their start in the coal mining industry. So where do they fit into the equation? According to Hans Greve, a Vice President with Aker Wirth, a manufacturer of roadheaders:

There are three basic ways to build a tunnel: convential drill-and-blast, fully mechanized with a TBM, or the in-between method with a roadheader," Greve said. "The roadheader is used for short tunnels - about 2 to 3 km [or about 1.5 miles] - that have self-supporting rock. But if the rock is too hard, the progress rate drops and the cost of wear and tear increases, so there is a certain point where roadheaders are no longer cost-effective.

[Source: Tunnel Business Online. Image: Tunnel Business Online]

 

Last Updated on Monday, 05 September 2011 22:31
 
Suggested Guidelines for Investigating Land Subsidence and Earth Fissure Hazards in Arizona PDF Print E-mail
Written by Randy Post   
Monday, 05 September 2011 15:16

Suggested Guidelines for Investigating Land Subsidence and Earth Fissure Hazards in Arizona

From the AZGS Document Repository:

These guidelines provide professionals evaluating site-specific conditions in areas known or suspected to be subsiding with a standardized minimum level of investigation for land-subsidence and earth-fissure hazards. The guidelines do not include systematic descriptions of all available investigative techniques or topics, nor is it suggested that all techniques or topics are appropriate for every project. Variations in site conditions, project scope, economics, and level of acceptable risk may require that some topics be addressed in greater detail than is outlined in these guidelines. However, all elements of these guidelines should be considered in comprehensive land-subsidence and earth-fissure hazard investigations, and may be applied to any project site, large or small. These guidelines are largely modified from draft recommendations prepared by Lund and others (2010). That draft, in turn, was developed using existing guidelines for preparing engineering geologic reports in Utah (Utah Section of the Association of Engineering Geologist, 1986), guidelines for evaluating surface-fault-rupture and land-subsidence hazards in Nevada (NESC, 1998), and guidelines for evaluating surface-fault rupture in California and Utah (California Geological Survey, 2002; Christenson and others, 2003), with additions and comments from various professionals involved in land-subsidence and earth-fissure investigations.

 

The Arizona Land Subsidence Interest Group contributed this report to the AZGS. I am a member of the group, albeit an inactive one. This document was commented on extensively by experts in consulting engineering geology, geotechnical engineering as well as agency representatives from the AZGS, APS, ADWR and others. Kudos to the group and those individuals who spearheaded the creation of this valuable resource. [Source: AZGS Document Repository. Image: AZGS]

Last Updated on Monday, 05 September 2011 22:20
 
Developing Production Pile Driving Criteria from Test Pile Data PDF Print E-mail
Written by Randy Post   
Monday, 29 August 2011 06:02
TRB Publication: Developing Production Pile Driving Criteria from Test Pile Data

From the report summary:

Although exploratory borings and engineering studies during design are an integral part of foundation engineering, the axial resistance of a driven pile foundation is ultimately determined by the criteria used to decide when to stop driving the pile during construction. The use of test piles for the purpose of developing the pile installation criteria can be instrumental in building driven pile foundations that are reliable and cost-effective. Nationwide practices for developing pile driving criteria range from the use of very simple formula without any test pile verification to the use of pre-production test piles with dynamic measurements during installation and static load testing. Many agencies employ a range of technologies and methods based on the size of the project, the type of pile, and the predominant ground conditions. However, this issue is handled differently from state to state based on local experience, economics, and other factors.

This synthesis provides a survey of the current practices used by transportation agencies to develop pile driving criteria, with special attention placed on the use of test pile data. The survey consists of questionnaires sent to all 50 state departments of transportation plus the District of Columbia and Puerto Rico; 44 of the 52 agencies provided responses. In addition, a Phase II Survey was performed by telephone interview with nine agencies representing a broad geographical distribution of large states that have extensive pile foundation construction projects.

The information collected indicated that practices used by transportation agencies to develop pile driving criteria for production pile installation can be described as highly variable in terms of the level and sophistication of the testing performed. To some extent, such variability in test pile requirements may reflect the inherent variety in project size, complexity, ground conditions, pile type, etc. However, a significant component of the variation in pile driving criteria may be related to the pace of implementation of new approaches to pile testing and variation among agencies with respect to training, experience, and acceptance of new technology.
[Source: TRB. Image: TRB]

 
Locata's Ground-Based GPS Mimic with Centimeter Accuracy PDF Print E-mail
Written by Randy Post   
Friday, 05 August 2011 00:24
Locata GPS-like device

The principle behind GPS technology is relatively simple, you have a network of satellites where their location is known to a high degree of accuracy, and you have a way to determine the distance between that transmitting satelite and the receiver. You need a minimum of 3 satellites to triangulate a location, and obviously the more you fix on, the better your accuracy. A company called Locata has a similar ground-based system that works on the same frequency as Wi-Fi and can be used to get location accuracy on the order of 1-cm! The military has been using it to track munitions on a missile range, but the technology is now being rolled out for civilian applications. I could see this being really useful on construction sites, in underground mines and perhaps for structural monitoring applications and probably more things. The units have a range of several kilometers. [Source: Slashgeo.org. Image: Technology Review]

 
Google Permissions - Google Maps / Google Earth Guidelines PDF Print E-mail
Written by Randy Post   
Friday, 05 August 2011 00:24

Wondering if you can use those Google Earth images in your report? How about your power point slideshow? What is Google Policy on using their Google Maps data for various purposes? Find the answers to this and more info on Google's Permissions page. They even have an interactive tool that will help you find the answers to your permission, attribution and other related questions. [Source: Google via Google Earth Blog]

Last Updated on Friday, 05 August 2011 07:27
 
Highway Reconstruction with Geofoam PDF Print E-mail
Written by Randy Post   
Friday, 05 August 2011 00:23
Geofoam project in Gary, Indiana

This is a nice little overview with Geofoam for people unfamiliar with the material and its applications. It was written by Mr. Nico Sutmoller with Insulfoam, who also contributed this article on a Geofoam project in Nebraska. [Source: Government Engineering via Geo-Institute Twitterfeed. Image: GE]

 
GeoConstructability - An Owner's Guide Obtaining Essential Geotechnical Information for Construction PDF Print E-mail
Written by Randy Post   
Sunday, 19 June 2011 15:24
Geo-Institute's GeoConstructability Report

A new report issued by the Geo-Institute and prepared by the Geotechnical Constructability Task Force is targeted at owners, and seeks to educate them on why they need the services of a geotechnical engineer and what types of geotechnical reports there are and what they should look for in those reports. These recommendations are based on the informal Geo-Coalition, comprised of geotechnical designers, specialty contractors and professional organizations similar to the Geo-Institute, such as AEG, ADSC, ASFE, DFI, PDCA and others. With so many people weighing in on this document over the past 5 years, it seems like geotechnical engineers had better pay attention to what these folks are saying should be in your report! I certainly will be looking it over. [Source: Geo-Institute. Image: Geo-Institute]

 
Seismic Analysis and Design of Retaining Walls, Buried Structures, Slopes, and Embankments PDF Print E-mail
Written by Randy Post   
Sunday, 05 June 2011 15:59

TRB’s National Cooperative Highway Research Program (NCHRP) Report 611: Seismic Analysis and Design of Retaining Walls, Buried Structures, Slopes, and Embankments explores analytical and design methods for the seismic design of retaining walls, buried structures, slopes, and embankments. The Final Report is organized into two volumes. NCHRP Report 611 is Volume 1 of this study. Volume 2, which is only available online, presents the proposed specifications, commentaries, and example problems for the retaining walls, slopes and embankments, and buried structures. [Source: TRB and NCHRP]

 
Mix Design Practices for Warm-Mix Asphalt PDF Print E-mail
Written by Randy Post   
Thursday, 02 June 2011 05:46

Mix Design Practices for Warm-Mix Asphalt from TRB

TRB's National Cooperative Highway Research Program (NCHRP) Report 691: Mix Design Practices for Warm-Mix Asphalt explores a mix design method tailored to the unique material properties of warm mix asphalt technologies.

Warm mix asphalt (WMA) refers to asphalt concrete mixtures that are produced at temperatures approximately 50°F (28°C) or more cooler than typically used in the production of hot mix asphalt (HMA). The goal of WMA is to produce mixtures with similar strength, durability, and performance characteristics as HMA using substantially reduced production temperatures. [Source: TRB. Image: TRB]

Last Updated on Thursday, 02 June 2011 12:47
 
ADSC Rock-Socketed Drilled Shafts in the SE Research Project Site No.2 PDF Print E-mail
Written by Randy Post   
Tuesday, 31 May 2011 15:08
Test boring at the rock-socket test site

A research project sponsored by the SE chapter of ADSC is back on track and preparing for more field tests of rock-socketed drilled shafts in rocks of the Piedmont. Click through to Dan Brown and Associates for more details. [Source: Dan Brown and Associates, PC. Image: DBA]

 
Evaluation of Bridge Scour Research: Geomorphic Processes and Predictions PDF Print E-mail
Written by Randy Post   
Monday, 23 May 2011 23:46

Evaluation of Bridge Scour Research: Geomorphic Processes and Predictions

TRB's National Cooperative Highway Research Program (NCHRP) Web-Only Document 177: Evaluation of Bridge Scour Research: Geomorphic Processes and Predictions explores the impact of long-term aggradation and degradation, and lateral river channel migration, on highway structures. [Source: TRB. Image: TRB]

Last Updated on Saturday, 21 May 2011 13:53
 
Recycled Rubber in Various Engineering Applications PDF Print E-mail
Written by Randy Post   
Tuesday, 10 May 2011 18:27
Used tires ready for recycling

Recycled rubber from tires has been used in various civil engineering projects. The California Department of Resources Recycling and Recovery (CalRecycle) promotes these uses which included RAC or rubberized asphaltic concrete as a friction enhancing and noise mitigation top layer on roadways. But there are other uses for the material as well. Tire-derived aggregate or TDA can be used as a lightweight backfill material to reduce loading on existing structures or lower driving forces on landslides and etc. Finally, the article describes how TDA was used for vibration mitigation under the subbase for a light rail line. [Source: Recycling Today via ASCE SmartBrief. Image: Tire Recycling]

 
<< Start < Prev 1 2 3 4 5 6 7 8 9 10 Next > End >>

Page 9 of 17