Useful Resources and tables:

 

LENGTH:
Conversion Factors
1 in	=	25.4	mm	1	mm	=	0.0394	in
1 in	=	2.54	cm	1	cm	=	0.3937	in
1 ft	=	0.3048	m	1	m	=	3.2808	ft
1 yd	=	0.9144	m	1	m	=	1.0936	yd
1 mile	=	1.6093	km	1	km	=	0.6214	mile
1 cm	=	10	mm	1	ft	=	12	in
1 m	=	1000	mm	1	yd	=	3	ft
1 km	=	1000	m	1	mile	=	1760	yd

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AREA:
Conversion Factors
1 in 2	=	645.2	mm 2	1	mm 2	=	0.0016	in 2
1 in 2	=	6.4516	cm 2	1	cm 2	=	1.155	in 2
1 ft 2	=	0.0929	m 2	1	m 2	=	10.764	ft 2
1 yd 2	=	0.8361	m 2		m 2	=	1.196	yd 2
1 mile 2	=	2.59	km 2	1	km 2	=	0.3861	mile 2
1 cm 2	=	100	mm 2	1	ft 2	=	144	in 2
1 m 2	=	10000	cm 2	1	yd 2	=	9	ft 2
1 km 2	=	100	hectares	1	acre	=	4840	yd 2
				1	mile	=	640	acres

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VOLUME
Conversion Factors
1 cm 3	=	0.061	in 3	1	in 3	=	16.387	cm 3
1 dm 3	=	0.0353	ft 3	1	ft 3	=	28.329	dm 3
1 m 3	=	35.3147	ft 3	1	ft 3	=	0.0283	m 3
1 m 3	=	1.308	yd 3	1	yd 3	=	0.7646	m 3
1 l	=	1.76	pint	1	pint	=	0.5683	l
	=	2.113	US pint			=	0.4733	US l
1 dm 3	=	1000	cm 3	1	ft 3	=	1.728	in 3
1 m 3	=	1000	dm 3	1	yd 3	=	27	ft 3
1 l	=	1	dm 3
				1	pint	=	20	fl oz
				1	gal	=	8	pints

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MASS
Conversion Factors
1 mg	=	0.0154	grain	1	grain	=	64.935	mg
1 g	=	0.0353	oz	1	oz	=	28.35	g
1 kg	=	2.2046	lb	1	lb	=	0.4536	kg
1 t	=	0.9842	ton	1	ton	=	1.016	t
1 g	=	1000	kg	1	oz	=	437.5	grains
1 kg	=	1000	kg	1	lb	=	16	oz
1 t	=	1000	kg	1	stone		14	lb
				1	cwt	=	112	lb
				1	ton	=	20	cwt

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FORCE
Conversion Factors									Unit
1 lbf	=	4.448	N	1	lbf	=	4.448	N	Newton	N
1 lbf	=	0.00445	kN	1	lbf	=	0.00445	kN	Kilonewton	kN
1 tonf	=	0.9964	MN	100	tonf	=	0.9964	MN	Meganewton	MN
				1	kgf	=	9.807	N
				1	tonf	=	9.964	kN

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PRESSURE & STRESS
Conversion Factors							Unit
1 lbf/m 2	=	6.895	kN/m 2				Kilonewton per square metre	kN/m 2
1 bar	=	100	kN/m 2				Meganewton per square metre	MN/m 2
1 tonf/ft 2	=	107.3	kN/m 2	=	0.1073	MN/m 2
1 kgf/cm 2	=	98.07	kN/m 2
1 lbf/ft 2	=	0.04788	kN/m 2

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COEFFICIENT OF CONSOLIDATION (Cv) or SWELLING
Conversion Factors				Unit
1 cm 2 /s	=	3.154	m 2 /year	Square metre per year	m 2 /year
1 ft 2 /year	=	0.0929	m 2 /year

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TEMPERATURE
Conversion Factors
°C	=	5/9 x (°F - 32)		°F	=	(9 x °C)/5 + 32

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TWO DIMENSIONAL FIGURES
Figure	Formulae to calculate area
Square	(side)2	Hexagon	2.6 x (side)2
Rectangle	Length x breadth	Octagon	4.83 x (side)2
Triangle	½ (base x height)	Trapezoid	height x ½ (base + top)
	OR	Circle	3.142 x radius2 or 0.7854 x diameter2 (circumference = 2 x 3.142 x radius
	v(s(s-a)(s-b)(s-c) where a, b and c are the lengths of the three sides and		or 3.142 x diameter)
	s=(a+b+c)/2	Sector of a circle	½ x length of arc x radius
	OR	Segment of a circle	area of sector - area of triangle
	a2 = b2 + c2 - (2b ccosA) where A is the angle opposite side a	Ellipse	3.142 x AB (where A = ½ x height and B = ½ x length)
		Bellmouth	3/14 x radius2

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THREE DIMENSIONAL FIGURES
Figure	Formulae to calculate volume	Formulae to calculate surface area
Prism	Area of base x height	Circumference of base x height
Cube	(side)3	6 x (side)2
Cylinder	3.142 x radius2 x height	2 x 3.142 x radius x (height - radius)
Sphere	4/3 x 3.142 x radius3	4 x 3.142 x radius2
Segment of a sphere	[(3.142 x h) x (3 x r2 + h2)] / 6	2 x 3.142 x r x h
Pyramid	1/3 of area of base x height	1/2 x circumference of base x slant height
Cone	1/3 x 3.142 x radius2 x h	3.142 x radius x slant height
Frustrum of a pyramid	1/3 x height [A+B+v(AB)] where A is the area of the large end and B is the area of the small end	1/2 x mean circumference of base x slant height
Frustrum of a cone	[1/3 x 3.142 x height (R2 + r2 +R x r)] where R is the radius of the large end and r is the radius of the small end	3.142 x slant height x (R + r)

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OTHER FORMULAE
Formulae	Description
Pythagoras' Theorem	A2 = B2 + C2 where A is the hypotenuse of a right angled triangle and B & C are the two adjacent sides
Simpson's rule	Volume = x/3 [(y1 +yn) + 2(y3 + y5) + 4(y2 + y4)]
	The volume to be measured must be represented by an odd number of cross sections (y1 - yn) taken at fixed intervals (x), the sum of the areas at even numbered cross sections (y2, y4 etc.) is multiplied by 4 and the sum of the areas at odd numbered imtermediate cross sections (y3, y5, etc.) is multiplied by 2, and the end cross sections (y1 and yn) taken once only. The resulting weighted average of these areas is multiplied by 1/3 of the distance between the cross sections (x) to give the total volume.
Trapezoidal rule	(0.16 x [Total length of trench] x [area of first section x 4 times area of middle section + area of last section])
Note:	Both Simpson's Rule and Trapezoidal Rule are useful in accurately calculating the volume of an irregular trench, or similar longtitudinal earthworks movement e.g. road construction

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WEIGHTS OF AGGREGATES
Material		kg/m3	Material		kg/m3
Ashes		610	Lime	Chalk (lump)	704
Cement	(Portland)	1600		Ground	761
Chalk		2406		Quick	880
Chippings	(stone)	1762	Sand	Dry	1707
Clinker	(furnace)	800		Wet	1831
Clinker	(concrete)	1441	Water		1000
Ballast or stone		2241	Shale/Whinestone		2637
Pumice		640	Broken stone		1709
Gravel		1790	Pitch		1152

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COMMON SITE MIXED CONCRETE MIXES FOR VARIOUS TYPES OF WORK
Mix	Class of work suitable for	Cement	Sand	Coarse	No of 25kg bags of cement per m3 of combined aggregates
				Aggregate
01:03:06	Roughest type of mass concrete such as footings, road haunchings 300mm thick	208	905	1509	8
02:05.5	Mass concrete of better class than 1:3:6 such as bases for machinery, walls below ground	249	881	1474	10
01:02:04	Most ordinary uses of concrete such as mass walls above ground, road slabs etc. and general reinforced work	304	889	1431	12
01:05.5	Watertight floors, pavements, and walls, tanks, pits, steps, paths, surface of two course roads, reinforced concrete where extra strength is required	371	801	1336	15
01:01:02	Work of thin section such as fence posts and small precast work	511	720	1206	21

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Brickwork Type	kg/m3		Blockwork Type	kg/m3
Common Fletton	1822		Aerated	650
Glazed Brick	2080		Dense Concrete	1800
Staffordshire Blue	2162		Lightweight Concrete	1200
Red Engineering	2240		Pumice Concrete	1080
Concrete	1841

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Soil Type	Approximate bulk of 1 m3 after excavation
Vegetable soil & loam	25 - 30%
Soft clay	30 - 40%
Stiff clay	10 - 15%
Gravel	20 - 25%
Sand	40 - 50%
Chalk	40 - 50%
Rock, weathered	30 - 40%
Rock, unweathered	50 - 60%

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Nominal sizes (mm)	Cross sectional area (mm2)	Mass per metre run (kg)
6	28.3	0.222
8	50.3	0.395
10	78.5	0.616
12	113.1	0.888
16	201.1	1.579
20	314.2	2.466
25	490.9	3.854
32	804.2	6.313
40	1256.6	9.864
50	1963.5	15.413

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Fabric reference	Mass	Longitudinal wires				Cross wires
		Nominal	Pitch	Area		Nominal		Pitch	Area
		wire size				wire size
	kg/m2	(mm)	(mm)	(mm2/m)		(mm)		(mm)	(mm2/m)
Square mesh
A393	6.16	10	200	393		10		200	393
A252	3.95	8	200	252		8		200	252
A193	3.02	7	200	193		7		200	193
A142	2.22	6	200	142		6		200	142
A98	1.54	5	200	98		5		200	98
Structural mesh
B1131	10.9	12	100	1131		8		200	1131
B785	8.14	10	100	785		8		200	785
B503	5.93	8	100	503		8		200	503
B385	4.53	7	100	385		7		200	385
B283	3.73	6	100	283		7		200	283
B196	3.05	5	100	196		7		200	196
Long mesh
C785	6.72	10	100	785		6		400	785
C636	5.55	9	100	636		6		400	636
C503	4.34	8	100	503		5		400	503
C385	3.41	7	100	385		5		400	385
C283	2.61	6	100	283		5		400	283
Wrapping mesh
D98	1.54	5	200	98		5		200	98
D49	0.77	2.5	100	49		2.5		100	49
Stock sheet size		4.8m x 2.4m = 11.52m2 per sheet

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Element	kg/m3 concrete
Pile caps	110 - to - 150
Tie beams	130 - to - 170
Ground beams	230 - to - 330
Bases	125 - to - 180
Footings	100 - to - 150
Retaining walls	150 - to - 210
Rafts	60 - to - 70
Slabs - one way	120 - to - 200
Slabs - two way	110 - to - 220

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