Sökning: "air voids distribution"

Hittade 5 avhandlingar innehållade orden air voids distribution.

  1. 1. Evaluation of Asphalt Field Cores with Simple Performance Tester and X-ray Computed Tomography

    Författare :Florentina Angela Farcas; Björn Birgisson; Xiaohu Lu; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; asphalt mixture; dynamic modulus; flow number; simple performance tester; X-ray computed tomography; air voids distribution;

    Sammanfattning : The importance of aggregate structure and air voids distribution for asphalt mixture rutting and cracking performance has been well established on the basis of experience and is well documented in the literature. Past and current investigations are limited to assessment of performance based on macroscopic behavior due to the difficulty associated with the quantitative measurement and analysis of the internal structure of asphalt mixtures. LÄS MER

  3. 2. Influence of fractures and air bubbles on the pressure distribution embankment dams

    Författare :Mats Billstein; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Vattenteknik; Water Resources Engineering;

    Sammanfattning : In some large embankment dams unexpected pore pressure distributions within the core have been observed. As an example, the piezometer pressures in WAC Bennett Dam, Canada, which rose for about four years after the reservoir was filled, were steady for two years and subsequently declined. LÄS MER

  4. 3. Durability of District Heating Pipes

    Författare :Stefan Forsaeus Nilsson; RISE; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; reuse of excavated material; district heating pipe; moisture diffusion; pipe joint; stone indentation; polyurethane foam; polyethylene; district heat distribution; long-term strength; buried pipe;

    Sammanfattning : This thesis is focused on mechanical loads and moisture related problems with a potential to critically harm the functionality of pre-insulated district heating pipes and pipe joints. Directly buried pipeline bends are investigated with respect to limiting deformations from a thermally induced lateral displacement. LÄS MER

  5. 4. Gradation-Based Framework for Asphalt Mixtures

    Författare :Bernardita Francisca Lira Miranda; Björn Birgisson; Terhi Pellinen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Asphalt; aggregate gradation; packing theory; asphalt microstructure; porosity; film thickness; rutting; moisture damage.; SRA - Transport; SRA - Transport;

    Sammanfattning : Asphalt mixture microstructure is formed by aggregates, bitumen binder and air voids. Aggregates make for up to 90% of the mixtures volume and the structure formed by them will depend mostly on their size distribution and shape. LÄS MER

  7. 5. Ageing of Asphalt Mixtures : Micro-scale and mixture morphology investigation

    Författare :Prabir Kumar Das; Björn Birgisson; Nicole Kringos; Andreas Loizos; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ageing; Aggregate packing; Atomic force microscopy; Asphalt mixture; Bitumen; Diffusion; Finite element analysis; Gradation; Micro-structure; Mixture morphology; Oxidative ageing; Surface ageing;

    Sammanfattning : There are many variables that affect the viscoelastic properties of asphalt mixtures with time, among which age hardening may be considered one of the important ones. Age hardening of asphalt mixtures is an irreversible process, which contributes to a reduction of the durability of pavements and eventually increases the maintenance cost. LÄS MER