Sains Malaysiana 39(1)(2010): 39–43

 

The Intragranular Textures of Aggregates and its Correlation

to the Physical Properties

(Tekstur dalaman Butiran dalam Agregat dan Perkaitannya

dengan Sifat Fizikal)

 

Azimah Hussain*

Program Geologi, Pusat Pengajian Sains Sekitaran dan Sumber Alam, Fakulti Sains dan Teknologi

Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor D.E., Malaysia

 

Colin Poole

Institute of Particle Science & Engineering

School of Process, Environmental and Material Engineering

Houldsworth Building, Clarendon Road

University of Leeds, Leeds LS2 9JT, United Kingdom

 

Received: 3 February 2009 / Accepted: 3 March 2009

 

ABSTRACT

 

To evaluate the correlation of the intragranular textures on the physical properties of coarse aggregates, four aggregates samples consisting of three granitoid sources and one limestone have been studied. The role played by intragranular textures (mineral assembladge, grain size and grain boundaries) in influencing the physical properties are potentially significant to the fact that such textural variation may complicate the aggregate strength. This study indicates that the aggregates exhibited variation in textural habits. The granitoid aggregates, which is rich with silicate composition has typical heterogranular textures of porphyritic and equigranular grain structures. Whereas the limestone aggregate comprises of bioclast and peloid allochems cemented by micrite and spar. The granitoid aggregates showed better dispersed characters and had extremely interlocking crystal boundaries which have more physical strength compared to a carbonate aggregate.

 

Keywords: Aggregate; physical properties; textures

 

ABSTRAK

 

Untuk menilai perkaitan antara tekstur dalaman butiran terhadap tabii fizikal bahan agregat, empat sampel agregat yang terdiri daripada tiga sumber granit dan satu batu kapur telah dikaji. Fungsi tekstur dalaman butiran (himpunan mineral, saiz butiran dan sempadan butiran) dalam mempengaruhi sifat fizikal, berupaya secara signifikan kepada situasi kepelbagaian tekstur yang merumitkan kekuatan agregate. Hasil kajian ini memperlihatkan bahan agregat yang dikaji menunjukkan kepelbagaian pencirian tekstur. Agregat granitoid yang kaya dengan komposisi silikat mempunyai tekstur heterobutiran tipikal iaitu forfiritik dan struktur butiran sama saiz. Sementara itu, agregat batu kapur yang mengandungi bioklas serta alokem peloid disimen oleh mikrit dan spar. Bahan agregat granitoid mempamerkan ciri yang lebih terserak, dan sempadan butiran yang amat saling-mengunci, mempunyai kekuatan fizikal lebih berbanding agregat karbonat.

 

Kata kunci: Agregat; sifat fizikal; tekstur

 

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*Corresponding author; email: azie6371@yahoo.com