Highway Concrete Pavement Technology Development and Testing

This study consists of continued field evaluations of treatments to four pavements suffering from distress due to alkali-silica reaction (ASR). One set of treatments was evaluated on existing pavements in Delaware, California, and Nevada that already showed ASR-related distress. Two of the existing pavements were located in relatively dry environments, while the third (in Delaware) was located in a moderately wet environment. The fourth site, in New Mexico, consisted of treatments on newly constructed pavements built with known reactive aggregates. At the Nevada site, the pavement was treated with methacrylate (HMM), silane, linseed oil, or lithium hydroxide. The Delaware site used only lithium hydroxide, while the California site used only methacrylate. The test sections in New Mexico consisted of pavement that contained admixtures as ASR inhibitors. There were two rates of addition of lithium hydroxide, a 25 percent replacement of cement with combinations of Class C and F fly ashes, and a high-range water reducer (HRWR). This evaluation showed that, unfortunately, none of the treatments were significantly beneficial to pavements with moderate to advanced ASR damage. The methacrylate sealer was effective when applied to a bridge deck and extended the pavement service life 3 to 5 years or more when applied in two to three coats. The results indicate that, regardless of the treatment, upward moisture migration from the subgrade to the bottom of the pavement is sufficient to support continued ASR even in dry desert climates. Preliminary results from the New Mexico test sites show that Class F ash, LOMAR (HRWA), or blended Class C and Class F ash may improve resistance to ASR distress. However, Class C ash can make deterioration much worse. Careful selection of the fly ash is necessary when attempting to mitigate known reactive aggregate. Continued monitoring of this test site is recommended.

Field test sections were constructed during 1992 as part of the Strategic Highway Research Program (SHRP) investigation of the frost resistance of concrete. The first freeze-thaw-related deterioration expected for pavement concrete exposed to de-icing salt would be salt scaling. Unfortunately, the test sections constructed in Ohio were diamond-ground between construction and the first visit of the monitoring team. The diamond-ground surface did not deteriorate over time. Internal deterioration of the Ohio test sections was either not detected or was believed to be caused by a mechanism other than freeze-thaw. Freeze-thaw deterioration was not noticed, either, in the Minnesota test sections (not exposed to deicing salts), though freeze-thaw tests conducted on specimens cut from the test sections 6 years after construction showed significantly different performance than specimens prepared and tested at the time of test section construction. For both the Ohio and Minnesota test sections, only 6 years of winter exposure would not be adequate to evaluate potential long-term performance thoroughly. Though the Ohio sections have been overlaid, making further monitoring impossible, the Minnesota sections are still exposed. Additional monitoring of these sections is recommended, along with providing salt exposure to the sections to determine their resistance to salt scaling. The D-cracking mitigation study indicated that in many cases the D-cracking returned after 6 years, independent of the mitigation technique tried. Additional testing would be required to make further evaluations.

Structural Steel Design: A Practice Oriented Approach

BS 5228:2009 Code of practice for noise and vibration control on construction and open sites

This part of BS 5228 gives recommendations for basic methods of noise control relating to construction and open sites where work activities/operations generate significant noise levels, including industry-specific guidance.
The legislative background to noise control is described and recommendations are given regarding procedures for the establishment of effective liaison between developers, site operators and local authorities.
This part of BS 5228 provides guidance concerning methods of predicting and measuring noise and assessing its impact on those exposed to it.

This part of BS 5228 gives recommendations for basic methods of vibration control relating to construction and open sites where work activities/operations generate significant vibration levels, including industry‑specific guidance.
The legislative background to vibration control is described and recommendations are given regarding procedures for the establishment of effective liaison between developers, site operators and local authorities.
Guidance is provided concerning methods of measuring vibration and assessing its effects on the environment.

BS 4978-2007 Visual strength grading of softwood – Specification

This British Standard specifies a method of strength grading softwood visually for structural use. The permissible limits of characteristics for two visual strength grades of softwood, General Structural Grade (GS) and Special Structural Grade (SS) are specified. This British Standard applies to softwoods, graded for use in the United Kingdom, for both within the United Kingdom and abroad.

The Building Environment: Active and Passive Control Systems

Get the updated guide to active and passive control systems for buildings.
To capitalize on today's rapidly evolving, specialized technologies, architects, designers, builders, and contractors work together to plan the mechanical and electrical equipment that controls the indoor environment of a building. The Building Environment: Active and Passive Control Systems, Third Edition helps you take advantage of design innovations and construction strategies that maximize the comfort, safety, and energy efficiency of buildings.

From active HVAC systems to passive methods, lighting to on-site power generation, this updated edition explains how to strategically plan for and incorporate effective, efficient systems in today's buildings. It covers the underlying thermal theories and thermodynamic principles and focuses on design that enhances the building environment and minimizes the impact on the world's environment. The Building Environment goes beyond the ABCs of HVAC and covers:

* On-site power generation, including wind turbines, solar photovoltaic cells, fuel cells, and more.
* Plumbing systems, fire protection, signal systems, conveying systems, and architectural acoustics.
* Procedures and/or formulas for performing heat loss, heat gain, and energy use calculations, determining the rate of heat flow, calculating solar energy utilization, doing load calculations, and more.
* Details on the latest building codes and standards references.
* New information on the sustainable design of building systems and energy efficiency, including new technologies.
* The latest thinking and data on a building's impact on the environment, indoor air quality, and "sick building syndrome."
* Design economics, including the payback period, life-cycle cost, comparative value analysis, and building commissioning.
* A practical on-the-job tool for architects, designers, builders, engineers, contractors, and other specialists, this Third Edition is also a great reference for architecture students who will lead tomorrow's design teams.

Fatigue and Fracture Reliability Engineering

Fatigue and Fracture Reliability Engineering is an attempt to present an integrated and unified approach to reliability determination of fatigue and fracture behaviour, incorporating probability, statistics and other related areas.

A series of original and practical approaches, are suggested in Fatigue and Fracture Reliability Engineering, including new techniques in determining fatigue and fracture performances. It also carries out an investigation into static and fatigue properties, and into the failure mechanisms of unnotched and notched CFR composite laminates with different lay-ups to optimize the stacking sequence effect. Further benefits include:

a novel convergence-divergence counting procedure to extract all load cycles from a load history of divergence-convergence waves;
practical scatter factor formulae to determine the safe fatigue crack initiation and propagation lives from the results of a single full-scale test of a complete structure; and
a nonlinear differential kinetic model for describing the dynamical behaviour of an atom at a fatigue crack tip.
Fatigue and Fracture Reliability Engineering is intended for practising engineers in marine, civil construction, aerospace, offshore, automotive and chemical industries. It is also useful reading for researchers on doctoral programmes, and is appropriate for advanced undergraduate and postgraduate programmes in any mechanically-oriented engineering discipline.

Content Level » Research

Keywords » Fatigue Reliability - Fatigue Reliability Analysis - Fracture Reliability - Reliability Design - Reliability Engineering

Related subjects » Mechanical Engineering - Physical & Information Science - Production & Process Engineering - Special types of Materials

TABLE OF CONTENTS
1. Deterministic Theorem on Fatigue and Fracture.- 2. Reliability and Confidence Levels of Fatigue Life.- 3. Principles Underpinning Reliability based Prediction of Fatigue and Fracture Behaviours.- 4. Data Treatment and Generation of Fatigue Load Spectrum.- 5. Reliability Design and Assessment for Total Structural Life.- 6. Reliability Prediction for Fatigue Damage and Residual Life in Composites.- 7. Chaotic Fatigue.

Tunnel Lining Design Guide