Modelling the Decrease of Total Soluble Salts of Clayey Soils during Long-term Soaking

Publisher's full text
Sabah Razouki
Jassim Najwa

Presented in this paper is an experimental investigation into the effect of long-term soaking on the decrease of total soluble salts (TSS) contents and distribution of moisture for compacted clayey gypsiferous soil. Two types (A and B) of clayey gypsiferous soils were used in this study. For each soaking period, two California bearing ratio (CBR) samples were prepared of type A soil and soaked under 70 and 10 lb (312 N and 45 N) surcharge loads suitable for highways. Various CBR soil samples of type B were prepared and soaked under 210, 140 and 70 lb (935 N, 623 N and 312 N) surcharge loads (suitable for airports) for the same soaking periods as type A CBR soil samples. For long-term soaking periods, a gradual drop in TSS (mainly gypsum) content took place at the top of CBR samples to reach a significant amount at the end of 180 days soaking. An empirical equation has been developed relating the initial total soluble salts contents to the total soluble salts contents after various soaking periods of CBR soil samples in the laboratory, taking into account the plasticity properties of the tested soils and the effect of surcharge load.

MEET US


25-26
Apr

Cost Benefit Analysis (CBA) workshop in Stockholm

An open seminar and workshop in Stockholm will be held on 25-26 April 2018. The workshop deals with the use of CBA as a basis for decision-making in the public sector. The workshop is organized by, among others, Professor Jan-Eric Nilsson, VTI.
13-14
Jun

The 6st Humanist Conference

The 6th HUMANIST Conference will take place 13-14 June 2018 in the Hague, The Netherlands. The scope of the conference covers a wide range of topics on Human Factors in Transport. Tania Willstrand and Alexander Eriksson will present their research results.

LATEST NEWS


2018-04-17

VTI will develop simulators for ambulance staff

VTI has initiated a pilot study for paramedics with the Centre for Teaching & Research in Disaster Medicine and Traumatology and Linköping University. The aim is to give ambulance staff the opportunity to practice critical medical tasks in a moving vehicle in...


2018-04-12

Unique electrified road opens in Sweden

The world’s first electrified road recharging the batteries of cars and trucks while driving opened in Sweden. The Swedish Minister for Infrastructure, Tomas Eneroth, was at the formal inauguration of the electrified road on April 11, 2018. VTI is one of 22...


2018-04-11

Swedish road safety spreads internationally

Sweden is a leading country in terms of road safety, and the research conducted by the Swedish National Road and Transport Research Institute (VTI) has contributed to increased safety. VTI’s remit includes disseminating research results and keeping up to date...


2018-04-06

A greater understanding of cyclists' behaviour

Cyclists are often accused of not following traffic rules and being hooligans on the road. New research shows that there is no support for this perception. "Our observations reveal no such general anarchy" says Sonja Forward, researcher at VTI.


2018-03-28

New technology for road surface measurement tested

VTI has tested a new scanning-laser technology for road surface measurement. The tests show the new technology for comprehensive transverse-profile measurement provides dependable values in measuring transverse profile and rut depth.


2018-03-15

Ulf Sandberg has been presented with the TTI Lifetime Achievement Award 2018

VTI’s Senior Research Leader Ulf Sandberg has been presented with the TTI Lifetime Achievement Award 2018 for his work on research into tyres and road surface.