Appendix I Single Storey House Drawings

Recommended by ERRA

Appendix II Comparison of Compressive Strength of Concrete Blocks

Prepared by PPAF & Available in Market

Compressive Strength test results for Concrete Blocks and Results of PPAF Concrete Mix Design

PPAF Test Results for Hollow Blocks (Compressive Strength at 10 days) Bagh

Sample Location Block

# Size Weight

Kg

10 days Psi

Avg 10

days Psi

Estd. 28

days Psi

1 16x 5 7/8 x 8 17.36 712 Shahid Block Factory, Hardigail near dispensary, Bagh 2 16x 5 7/8 x 8 15.48 396 554 739

3 15 1/4x5 7/8x8 16.18 365 Jamil Block Factory, Hardigail, Bagh 4 15 1/4x5 7/8x8 16.00 318 342 455

5 15 1/4x5 7/8x8 15.42 696 Friends Enterprise near Rafiqabad, Bagh 6 15 1/4x5 7/8x8 15.16 435 566 754

7 15 1/4x5 7/8x8 16.84 399 Ittehad Block Factory, Nagmanpura, near Pulmera, Bagh 8 15 1/4x5 7/8x8 16.16 290 345 459

9 14 7/8 x 5 7/8x 8 14.59 440 Ahmadabad Block Factory near Nagmanpura Petrol Pump Bagh 10 14 7/8 x 5 7/8x 8 14.42 337 389 518

11 15 3/4 x 6 x 7 3/4 16.08 369 Amjad Gardezi Block Factory, near bypass road, Hadabody, Bagh 12 15 3/4 x 6 x 7 3/4 17.14 448 409 545 Rawalakot

Sample Location Block

# Size Weight

Kg

10 days Psi

Avg 10

days Psi

Estd. 28

days Psi

1 15 3/8 x 5 7/8 x 8 17.34 652 Farhan Block Factory, near PPAF office, Rawalakot 2 15 3/8 x 5 7/8 x 8 15.88 422 537 716

3 15 1/4 x5 3/4 x7 1/2 14.40 583 Rafique Block Factory, Darak, near Eidgah, Rawalakot 4 15 1/4 x5 3/4 x7 1/2 14.70 563 573 764

5 15 x 5 7/8 x 7 3/4 14.22 718 Al-Hassan Methal Merra, Rawalakot 6 15 x 5 7/8 x 7 3/4 14.33 619 669 891

7 15 x 6 x 8 13.90 346 Sharif Block Factory, Darak near Eidgah, Rawalakot 8 15 x 6 x 8 14.04 493 420 559

9 15 1/8 x 5 7/8 x 8 15.02 417 Hasrat Block Factory, near NADRA office, Rawalakot 10 15 1/8 x 5 7/8 x 8 15.04 441 429 572 Mansehra

Sample Location Block

# Size Weight

Kg

10 days Psi

Avg 10

days Psi

Estd. 28

days Psi

1 16x 6 x 8 15.00 214 Kaghan road, Mansehra 2 16x 6 x 8 15.80 471 343 457

Note: None of the blocks tested have the specified strength1. Average varies from a low of 253 Psi to 669 Psi.

1 (28 days ASTM C 90: 1700 Psi net area unit compressive strength, average of three units to be not less than 1900 Psi; if based on gross area then 1000 Psi.)

Compressive strength test results for PPAF concrete mix designs for solid blocks

(Compressive Strength at 10 days)

Mix (cement: sand: aggregate) Block

# Size Weight

Kg

10 days Psi

Avg 10

days Psi

Estd. 28

days Psi

1:2:4 1 12 x 8 x 6 15.00 2421 2 12 x 8 x 6 15.80 2236 2,329 3,105

1:3:6 1 12 x 8 x 6 22.40 1545 2 12 x 8 x 6 22.26 2154 1,850 2,466

1:4:8 1 12 x 8 x 6 15.00 1614 2 12 x 8 x 6 15.80 1591 1,603 2,137

1:6 (cement:river bed material) 1 12 x 8 x 6 15.00 2793 2 12 x 8 x 6 15.80 3065 2,929 3,905

1 12 x 8 x 6 15.00 2282 1:8 (cement:river bed material) 2 12 x 8 x 6 15.80 2282 2,282 3,043 1 12 x 8 x 6 15.00 1451 1:10 (cement:river bed material) 2 12 x 8 x 6 15.80 1358 1,405 1,873 1 12 x 8 x 6 15.00 1350 1:3:6 with hole 2 12 x 8 x 6 15.80 1427 1,389 1,851 1 12 x 8 x 6 15.00 1521 1:3:6 half block 2 12 x 8 x 6 15.80 1890 1,706 2,274

Note: Trials show that 1:3:6 and 1:4:8 both provide adequate strength (28 days ASTM C 90: 1700 Psi net area unit compressive strength, average of three units to be not less than 1900 Psi; if based on gross area then 1000 Psi.). Even 1:8 blocks using river bed material gave satisfactory results. The key is to have proper mix design, water : cement ratio and adequate curing.

PPAF Test Results for Solid Blocks (Compressive Strength at 10 days) Mansehra

Sample Location Block

# Size Weight

Kg

10 days Psi

Avg 10

days Psi

Estd. 28

days Psi

1 16x 6 x 8 20.8 565 Chinar Road Mansehra 2 16x 6 x 8 21.1 671 618 824 3 12 x 5.5 x 5.5 11.98 269 Ghandian Road Mansehra 4 12 x 5.5 x 5.5 12.21 269 269 359 5 12 x 5.5 x 5.5 14.32 250 Badara Chowl 6 12 x 5.5 x 5.5 14.32 255 253 337

Appendix III Calculation of Seismic Forces

Developed in Masonry Wall

Seismic Force Direction

Walls resisting Seism

ic Forces

Seismic Forces for Masonry Structure with 6 Solid Blocks

As per UBC-97, base shear is calculated as follows:

WRTCvIV =

Where

Cv = Seismic Co-efficient; Table 16-R

R = Overstrength Factor; Table 16-N

I = Importance Factor; Table 16-K

T = Time Period; Ct(hn)3/4 where Ct = 0.02

W = Weight of the Building

R=Overstrength Factor; Table 16-N

I=Importance Factor; Table 16-K

T=Time Period; Ct(hn)3/4 where Ct = 0.02

Cv = 0.96; R=4.5; I=1; T=0.1125(where height of the building is taken as 10)

Weight of Building (Room 15x15; ht=10ft):

Roof Level: (30.15.15 + 6/12x3/2x15x4x145)/1000 = 13.30k

Lintel Level: 6/12(3/2x15)x4x145 + 6/12x(4/2x15)x4x145 = 15.225 k

Sill Level: 6/12x(4/2x15)x4x145 + 6/12x(3x15)x4x145 = 21.75 k

Total weight, W = 50.275 k

V=0.96x1x50.275/(4.5x0.1125)

V= 95.33 k

But shall not exceed

V= 2.5x0.44x50.275.0/4.5 Eq. 30-5

V= 12.3 k governs

a) Seismic Forces when earthquake is applied in the weaker direction of the wall

Base shear V is distributed statistically and following are the value at different level:

Roof Level: 5.37 k

Lintel Level: 4.30 k

Sill Level: 2.63 k

Since two walls (hatched) will resist above seismic forces. Hence seismic forces to be divided by 2 while analyzing one wall.

Hence, seismic forces on one wall:

3ft

4ft

3ft

Seismic Band at Roof

Seismic Band at Lintel

Seismic Band at Sill

Roof Level: 2.68 k

Lintel Level: 2.15 k

Sill Level: 1.32 k

b) Seismic Forces when earthquake is applied in the weaker direction of the wall

In this case, the calculated base shear is applied uniformly on the wall face.

For solid block wall; the earthquake pressure is approximated as:

Base shear, V=12.3kips

Pressure on the wall = 12.3/(15x10) x 1000/4

= 20.5 Psf

Seismic Force

Wall resisting Seism

ic Forces

Seismic Force Direction

Walls resisting Seism

ic Forces Seismic Forces for Masonry Structure with 6 Hollow Blocks

As per UBC-97, base shear is calculated as follows:

WRTCvIV =

Where

Cv = Seismic Co-efficient; Table 16-R

R = Overstrength Factor; Table 16-N

I = Importance Factor; Table 16-K

T = Time Period; Ct(hn)3/4 where Ct = 0.02

W = Weight of the Building

R=Overstrength Factor; Table 16-N

I=Importance Factor; Table 16-K

T=Time Period; Ct(hn)3/4 where Ct = 0.02

Cv = 0.96; R=4.5; I=1; T=0.1125(where height of the building is taken as 10)

Weight of Building (Room 15x15; ht=10ft):

Roof Level: (30.15.15 + 6/12x3/2x15x4x(2/3x145))/1000 = 11.10k

Lintel Level: (6/12(3/2x15)x4 + 6/12x(4/2x15)x4)x(2/3x145) = 10.15 k

Sill Level: (6/12x(4/2x15)x4x145 + 6/12x(3x15)x4)x(2/3x145) = 14.50 k

Total weight, W = 35.75 k

V=0.96x1x35.75/(4.5x0.1125)

V= 67.80 k

But shall not exceed

V= 2.5x0.44x35.75.0/4.5 Eq. 30-5

V= 8.58 k governs

a) Seismic Forces when earthquake is applied in the weaker direction of the wall

Base shear V is distributed statistically and following are the value at different level:

Roof Level: 4.22 k

Lintel Level: 2.70 k

Sill Level: 1.65 k

Since two walls (hatched) will resist above seismic forces. Hence seismic forces to be divided by 2 while analyzing one wall.

3ft

4ft

3ft

Seismic Band at Roof

Seismic Band at Lintel

Seismic Band at Sill

Hence, seismic forces on one wall:

Roof Level: 2.11 k

Lintel Level: 1.35 k

Sill Level: 0.83 k

b) Seismic Forces When Earthquake is Applied in the Weaker Direction of the Wall

In this case, the calculated base shear is applied uniformly on the wall face.

For solid block wall; the earthquake pressure is approximated as:

Base shear, V=8.58kips

Pressure on the wall = 8.58/(15x10) x 1000/4

= 14.3 Psf

Seismic Force

Wall resisting Seism

ic Forces

Appendix IV Stresses Developed in

Block Wall

Case 1: Earthquake applied in the major direction of the wall made of solid blocks Load1: Stresses due to earthquake load only; (Stress= 22.0 Psi)

Load 2: Stresses due to dead load; (Stress= 100.4 Psi)

Combination of Load 1 + Load 2 (Stress= 101.2 Psi)

When slenderness effect of wall is not considered (Stress = 24.0 Psi)

Moment at Seismic Band

Moment at Wall; 147.6 lb.ft

Max. moment; 235.8 lb.ft

Case 2: Earthquake applied in the minor(weaker) direction of the wall made of solid blocks Load1: Only earthquake forces (23Psi)

Due to dead load 102.2Psi

Combination of Load 1 + Load 2 (118.6Psi)

Case 2: Earthquake applied in the minor(weaker) direction of the wall made of solid blocks Moment at Seismic Band

Moment at Wall; 172.9 lb.ft

Max. moment; 275.8 lb.ft

Appendix V Calculation of Soil Bearing

Capacity

Average Stress =

Average Stress =

Hence soil bearing capacity is adequake to undertake such stresses.

30 "

30 "

Tons/sft30 x 30 x 2.24 x 1000

=90 x 6 x 30 x 144

= 1.157

b) FOR 6" SOLID CONCRETE BLOCKS :

90 psi

=60.0 x 6 x 30 x 144

= 0.771

a) FOR 6" HOLLOW CONCRETE BLOCKS :

60 psi

Tons/sft30 x 30 x 2.24 x 1000

CHECK FOR SOIL BEARING CAPACITY :