000			03521nam a22002657a 4500
008			260505t2022 bx ao||g m|||o00| 0 eng d
040			_aUniversiti Teknologi Brunei _beng _cUTB
084			_aUTB 120 REPORT THESIS & DISSERTATION _aRTDS 445
100	1		_aTang Eng Hie _eAuthor.
245	1	0	_aEnhancing Flexible Pavement Performance Through Stabilising the Sub-base Layer and Adding Crumb Rubber to the Wearing Course / _cTang Eng Hie
260			_aBandar Seri Begawan : _bUniversiti Teknologi Brunei , _c© 2022 .
300			_axx, 154 pages : _bphotos, illustrations ; _c30 cm.
500			_aThesis submitted for the degree of Master of Science by Research in Civil Engineering Universiti Teknologi Brunei
500			_aAbstract Roads constructed on weak-bearing natural subgrade soil having fluctuating groundwater level and experiencing rainfall-induced flooding and traffic overloading are susceptible to pavement deteriorations that drastically reduce pavement durability, serviceability, lifespan and safety. While an appealing option that reduces construction cost and time, accelerates strength development over a short curing period is to chemically stabilise native sandstone aggregate with polymer, cement or polymer-cement blend when used in the sub-base, a sustainable option that offers improved wearing course is the partial replacement of imported mineral aggregate with crumb rubber while treating the asphalt mixture with hydrated lime. To achieve the aims to optimise the use of local sandstone aggregate in the sub-base and to introduce the use crumb rubber in the wearing course, the research evaluates experimentally and compares the (quantitative) engineering strengths of sandstone aggregate before and after chemical stabilisation and evaluates the (quantitative) engineering performance of crumb rubber modified dense-graded hot mix asphalt when compared to conventional dense-graded hot mix asphalt. Outcomes from the soil stabilisation laboratory investigations had shown that the (1) gradations, (2) cement contents, (3) polymer contents, (4) polymer-cement blend contents at which the gravel:sand ratios, unconfined compressive strengths, indirect tensile strengths and California bearing ratio met the design requirements were (1) 1.2–2.1, (2) 3%–5%, (3) 0.5%–1% and (4) 0.75%–3%–0.75%–5%. The minimum dry curing periods for the cement-stabilised, polymer-stabilised and polymer-cement-stabilised samples were 3, 7 and 7 days respectively. Outcomes from the asphalt modification laboratory investigations had shown that the optimum bitumen content and optimum rubber content, at which the percentage voids of asphalt, percentage voids in mineral aggregate, percentage voids filled with bitumen, percentage of absorbed bitumen and Marshall stability and flow for diorite-based samples using 0.71mm and 2mm rubber sizes and granite-based samples using 2.36mm rubber size were within the permissible ranges, were 5.5%–6.0% and 1%–2% respectively.
502			_aThesis (Master) - Universiti Teknologi Brunei, 2022
504			_aIncludes bibliographical references from page 138-153
610		4	_aUniversiti Teknologi Brunei _vThesis
610		4	_aUniversiti Teknologi Brunei _vFinal Year Project
650		4	_aPavements _xSubgrades
650		4	_aSoil stabilization
650		4	_aCrumb rubber
700	1		_aEl-Said M M Zahran _cDr. _eSupervisor.
942			_2lc _cRTDS _n0
998			_eReports, Thesis & Dissertation _s850663 : 002498 c.1_UTB _xUniversiti Teknologi Brunei
999			_c24052 _d24052