This study evaluates the physical, mechanical and in-situ properties of the rock aggregates in Kajuru, Kaduna State, Nigeria as sources of aggregate for construction purpose. The uniaxial compressive strength was determined by using Universal Testing Machine to crush cored samples and Schmidt rebound number by Schmidt hammer apparatus. While the engineering destructive tests were carried out on aggregates using various apparatus. Na 2 SO 4 solution was used for soundness test and glass jar for determination of specific gravity. The results indicate that specific gravity ranges from 2.48 to 2.88, the moisture content of samples are within 2%. The UCS ranges from 95.76Mpa to 169.70Mpa while the Schmidt rebound number ranges from 29.4 to 35.3. Comparing the Los Angeles abrasion, impact and crushing value obtained from the laboratory destructive test with the B.S standards, most of the rock can be used for construction works. The results also indicate that there is direct proportional relationship between compressive strength with Schmidt rebound number and specific gravity. Inverse relationship exists between moisture content with specific gravity and compressive strength. The physical and geotechnical properties were found to be dependent on the chemical and petrographic characteristics of the rock.

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Uncertainties and difficulties surrounding laboratory strength testing of peat have caused the increasing reliance on in situ testing methods, which include T-bar and ball penetrometers, to determine the undrained strength of peat for design purposes. This paper presents the results of miniature full-flow penetrometer (T-bar and ball) tests on decomposed peat samples to provide a better understanding of the interpretation of the strength parameters in this material. The tests were conducted in a pressure chamber, in which miniature T-bar and ball penetrometer tests can be performed on peat samples consolidated under specific vertical effective stresses. Penetrometer bearing factors were derived experimentally using the monotonic penetration resistance and the undrained shear strength estimated from triaxial tests. The bearing factors, expressed as the penetration resistances normalised by the undrained shear strength data (obtained from triaxial tests) compare well with those derived from plasticity solutions. In addition, the remoulded strength parameters derived from penetrometer cyclic tests are comparable with those obtained from fall cone tests. The findings reported in this paper illustrate the capability of full-flow penetrometer tests to measure the undrained strength of peat.

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This paper presents a review of the advances in the variable penetration rate testing methods on inorganic soils and its potentials to investigate the appropriate penetration rate and resistance factors for penetrometer testing of peat. A partially drained condition, which often leads to misinterpretation of test results, has been observed in peat penetration testing when the standard rate of 20 mm/s is used. Although the impact of rate-effects on penetration resistance measured with CPTu, T-bar and ball penetrometer have been investigated extensively in various intermediate soils, research is limited on how penetration rate controls drainage conditions and affects consolidation behaviour in peat. This review synthesises research developments in using variable penetration rate tests. The objective is to evaluate the transition of drainage conditions and consolidation behaviour of inorganic soils while focusing on its adaptability for peat. The review provides guidance on the investigation of the penetration rate testing in peat.