Section 4 Side Longitudinals

401. Side longitudinals

1. The section modulus of side longitudinals in the midship part below the freeboard deck is not to be less than obtained from the following formula, which ever is the greater.

ĚÌ Ņ KǾĴ Ċᾜᾨ

Ī Ņ Ǿ Ρ̓Ü

Ī (cm3), Ě Ī Ķ Ã Ċᾨ Ī (cm3)

where:

Ċ = Spacing of longitudinals (m)

ᾨ = Distance between the web frames or between the transverse bulkhead and the web frame in- cluding the length of connection (m)

ᾜ = Vertical distance (m) from the longitudinals to a point specified in the following

30 m P Ã ≤

90 m

: ᾘ Ñ LǾLĨĨ Ã Ň LǾJĨ

(above top of keel)

90 m P Ã

: ᾘ Ñ LǾLĮK Ã (above top of keel)

2. Beyond the midship part, the section modulus of side longitudinals may be gradually reduced to- wards the end of barges, and may be 0.85 times that obtained from the formula in Par 1 at the ends. However, the section modulus of side longitudinals between 0.15 Ã from the fore end and the collision bulkhead is not to be less than obtained from the formula in Par 1.

3. The depth of f1at bars used for longitudinals is not to exceed 15 times the thickness of flat bars.

4. Side longitudinals on sheer strakes in the midship part are to be, as far as possible, of slenderness ratio not greater than 60.

5. The section modulus of bilge longitudinals need not exceed that of bottom longitudinals.

402.

Side transverse

1. The side transverse supporting side longitudinals are to be arranged at an interval not exceeding

about 4.8 m at positions where solid floors are

2. The scantlings of side transverse are not to be

provided.

less than obtained from the following formula:

Ì

Section modulus: Ě Ņ Ǽ Ċᾜᾨ Ī

(cm3), Thickness of web: ᾼ Ņ

ǼĪĊᾜᾨ ÜᾘL

Ñ ÌǾJ (mm)

where:

S = Side transverse spacing (m)

l = Vertical distance from the top of inner bottom plating or single bottom floors at side to the deck at the top of side transverse. Where, however, there are effective deck trans-

verses, l

may be measured up to the lower surface of such transverses (m)

d0

= Depth of side transverses (mm). However, the depth of slots for side longitudinals is to be deducted from the web depth

h = Vertical distance (m) from the lower end of l to a point specified in the following, but in no case 1s it to be less than 1.43 l

30 m P Ã ≤ 90 m : ᾘ Ñ LǾLĨĨ Ã Ň LǾJĨ (above top of keel)

90 m P Ã

: ᾘ Ñ LǾLĮK Ã

(above top of keel)

C1 and C 2 = Coefficients given in Table 9.2.

Table 9.2 Coefficient C1 and C2

3. Side transverses are to be provided with tripping brackets at an interval of about 3.0 m and stiff- eners are to be provided on the webs at each longitudinals. However, for the middle part of the span of side transverse they may be provided at alternate longitudinals.