386
ENQUIRY INTO COLLAPSES
OF
HOUSES.
KOWLOON CITY ROAD.
The enquiry into the fatal collapses of houses in Kowloon City Road on 18th July last was re- sumed on the afternoon of the 7th inst. before Mr. F. A. Hazeland. Mr. H.L Denugs, Acting Crown Solicitor, appeared on behalf of the Go- vernment, while Mr. H. W. Looker represented the architects, Messrs, Leigh & Orange, and Mr. C. D. Wilkinson the contractors, the Loong Cheong fira.
H.
aud to construct water-channels thereon; this had partly been done, aud at the time of the collaps the chanuelliuz had al beeu completed, as well as th concreting of the passage-way between the two blocks. Noue of the surface concreting had been done at the back of the two blocks at the time of the collapse, and it was not ye: doue. Witness believed it was the case that some
!
THE HONGKONG WEEKLY PRESS AND the time the Government gave their certificate. A wall was not necessarily dangerous because it was 1 inches out of plumb. The wall in .question was at present out of plumb, but he did not consider tha for that reason it was dangerous. It was the same in the case of the back wall on Lot 1,17--it was not necessarily dangerous because it was a little out of plumb, nor was the north wall on the same lot as it now Witness, however, would not grant a stood. certificate for it in its present condition, becaus- it had not been completed in accordance with the deposited plans for rebuilding it; the wall H. P. Tooker, executive engineer, P.W.D.,
was now being completed in accordance with was examined. He reconated the cirļumstance
those plans, and when that was doue he would, not consider any further action necessary. of the collapse on 18th July last, and said that
There was probably a subsidence of the founda- the fallen wall had been rebuilt ; it was not, how-
tious of No. 30 between the date of the graut- ever, in plumb, the lower seven feet-hat was,
Wit seven feet above the ground-being 11 inches ing of the certificate and the collapse. out of the straight. The back wall of the
ness had not noticed any subsidence of the same block was also out of plumb Witness had foundations ander the the veraudali pie. 8, where not plumbed the south wall of the block, but the pressure would probably be greatest. this wall had been pulled down and was being had not seen the foundations himself, aul he had rebuilt. The south wall of house No. 32, the Lot the sli. htest reason for doubting Mr. Leigh's His greater portion of which fell down on 18th July, statement that they were p rfectly good. was also rebuilt and had been plumbed. Some opinion was that the subsidence was caused by time in May last witness's attention was called the accumulation of water owing to the heavy to the north wall on beck 1.1 8. which was then
rains, and the sugested precautions for divert shored up and being rebuilt. On 19th July being the water should have been t.ken in the inspected the houses, and looked at the brick interests of the people living in the houses. and mortar debris. The bricks he found to be
It was the duty of the Government to have concreted the laue at the back of the two blocks hard, but some were more or less soaked by the rain which had come down immediately after the collapse.There was nothing however, to lead him to suppose from what he saw that day, that the bricks or mortar had be u wet or soddened before the collapse, nor did he see any bricks so sot that they e ull be eut in the haud. As far as witness could judge. tie position of the ground floor wall of No. 30 was the saute then as it was th-day, but he did not notice then that that wall was out of plun. b. The ways in which the collapse of the wall of No. 3 might have occurred were- (1) crushing of the bricks, caused by bad or soft bricks; (2) th- bouding might have been bad; (3) the mortar might have been bad causing the bricks to slide and giving them no coh sion; (4) the wall might have been built out of plum to such an extent as to cause i to totter; (3) there might have been a sub- sidence in the foundatious; (i) there might have been an ext aordinary force, such as a heavy wind in a typhoon; and (7, the.e might have been a combination of any or all of these reasons, which were based on the assumption that the wall of No 30 was not knocked down by that of No. 32. Witness was of opinion that the immediate cause of the collapse was the force of the wind, but he could not say whether that force was applied outside or inside the Louse. If the houses hd been in perfect condition at the time of the collapse he thought that the wind ought not to have knocked them down he also thought that the reason they were knocked down by the wind was that there was a subsidence of the fonudations. The fact of the north and west wals on Lot 1,107 being out of plumb agreed with the theory that such a subsidence had taken place. The sites for the two blocks of houses were cut out from the hillside, on the western side of Kowloon City Road, and the effect of this was to cause the bill at the back of the houses to slope towards the buildings, which, from persoĝal observa- tion, witness kuew caused the water due to the heavy rains to pour from the hillside into the sites; furthermor, he observed the water lying in phols immediately at the back of the house and he Rew that soil water was close to the surface. From what be saw, witness concluded that the north wall on Lot 1,18 sauk before it was recou- stracted, and since it had been rebuilt he believed the foun sacions had sunk again; this opinion was formed from the way. If wa I was cracked. No special precautions, so far as he was awyre, were taken, with ref.rence to these to blocks, to prevent the foundations from subsiding in conse- quence of the moist nature of the ground; he thought that precautions ought to have been taken to prevent the heavy flow of water from the hillside on to the sites. This might have been don by digging a tatch-water on the side of the hill, or by otherwise draining the water
away.
the
sul-
By Mr. Looker-Witness was of opinion that the wall of No. 30 was not out of plumb at
1
[November 17, 1902.
The
the work appeared to be very fair. The bricks were good, and he saw nothing to complain of. his opinion was that the cause of the collapse was insufficiency of strength in a wall of such large area although the wall was built in accordance with the requirements of the Ordinance fact of its length being over 35 feet was not spec ally brought before him, but had it been he did cot think he would have objected. As- to the cause of the collapse, witness expl.ined. he would like also to mention the vibration set up by a heavy storm. He did not agree with Mr. Leigh when he said- To my mind the col- lapse of this wall was chiefly attributable to the disintegration of the brick-work by the wet." Witness had also gren 45, Praya East, and he also disagreed with Mr. Leigh's tory in the case of that house, namely, that the collapse was due to the squeezing up
Ia of the mortar in the well through wet. of ertain houses +xamined
by the case wituess which had suffered from wind and rain, was coutrary the walls bad bulged, which to Mr. Leigh's theory as to the squeezing of the mortar. If a house in Hong- kong had been properly built, aud had had half an inch of plaster covering the exterual wall, the rain should not have so soddened the plaster and softened the brickwork as to cause the wall to collapse, unless the storm was very abnormal. He had never known such a thing happen in Hongkong. The buildings completed in the Colony between May, 1901, aud May, 1902, both inclusive, amounted to 14, and of the houses mentioned in the official list of collapses, the following were plated betwe u 1st June, 1991, and 18th July, 1902:-Nos. 30 and 32, Kowloon City · Road and Nos. 1, 3, 5, 7, and 9, Lo Lung Hang, Hunghom. The great majority of the houses mentioned in that list were old village houses, probably built by the villagers themselves with- out any architects, and a large number were cours of construction. houses actually in
up
uine
com -
months before the time of the collapse Leigh & Oring wrote to the P. W. D. and asked that the concreting be proceeded with. The con- creting of the lane at the back and of that in the middle, supposing it had been done some; Questioned as to the time in which new work months before the collapse, wo ld not hav-sould become seasoned, Mr. Chatham gave
it his opinion that prevented the flow of water that witness refered it as
took between twelve months for a wall 10 and t: concreting was merely a sanitary precaution,
wall was finished in It was not the duty of the Government as much become dry, and if a as anybody else to tave measures to prevent February, 1901. he should say that it would be the flow of water from the hill-ide; a catch absolutely dry in February 1902. Properly water similar to one the architects had made speaking, a wall should be able to withstand the behind the block of houses on Lot 1,1.8 should weather from the time the building was com- have been constructed. With ss did not koow pleted. how that cate water came to be constructed. and he was not aware if a catchwater precisely similar to the one be suggested was placed by the Government at the back of Hunghom Iuland
Lots 222 and 223
The hearing was adjourned till Wednesday afternoon at 2.15.
On the 12th inst. Mr. H. P. Tooker again went into the witness-box and completed the evidence begun by him on the last occasion of the enquiry.
By Mr. Wilkinson-Witness was of opinion that the immediate cau-e of the co.lipse was the typhoon and the main cause the subsidence of the foundations, consequent on the heavy flow of water. If the upper part of a wall had a tendency ontwards, it was probable that the lower part would also be dragged forward. and that might explain why the remaining portion of the collapsed wall at No. 30 was out of plumb. Witness was satisfied a to the quality of the material used; in his opinion it was good. By Mr. Dennys-The wall through which one of the tie-rods had been pulled was eighteen inches thick, but the fact of its being so pulled through did not necessarily show that th - brick- work was particularly wet.
Hon. W. Chatham, D.rector of Public Works, was the next witness. After stating when hisattention wa first especially directed to the two houses, Nos 31 and 32, which was on 9th July, the day following the collapse, he said that special allusion was made in the local Buildings Ordinance to walls ex-e diug 35 feet in length: that Ordinance made provisi o for increasing the thickness of walls in consideration of their being of extra length, and this would bring the local law rather in excess of the law of Eu land. The reasons for its being in excess were because the workmanship was not so good here, the wea her was very trying and in many cases the materials were inferior. On 19th July. Mr. Chatham continued, he had a good lock round, and
No. 45, Praya East. was finished in February, 1901, and collapsed on 2nd August this year.
He did not agree, said witnes«, with
Mr Leigh in theorising that the cause of the col apse in that case was the same as that in reference to Nos. 30 and 2, Kowloon City Road. The collapsed houses in Lo Lung Hang, Hung om. were designed by a Chinese architect.
Toe enquiry was agai, adjourned,
On the enquiry's resumption on the 13th inst. Hoa, W. Chatham again went into the wit- nass box, and was questioned by Mr. Looker. So far as he could obs-rve, he said, he was satisfied that the north wall of No. 30 was built in compliance with the requirements. of the Building Ordinance, and he was aware that a certificate to that effect had been granted by Mr Loker. Speaking generally, wi ness should not say that tie-rods were better than eros-walls for holding in an external wall; cross walls gave rigidity to an external wall. as well as a certain amount of holding in. If it were simply a case of holding in, however, a tie-rod would be the proper method to adopt. Witness did not agree with Mr. Looker's theory about the flow of water from the bill- -side causing a subsidence of the foundations. The extraordinary number of collapses this year seemed to point to the presence of some unusual fact or element which bad not hitherto existed, and undoubtedly the prolonged rainy sea on and the wind which prevailed during that season had some influence in causing those collapses. The bulging of walls in the houses in Kowlon City Road he attributed more to the wind than to the wet weather, but he had certainly known cases at the Peak where damp- caused by rain had penetrated to the inside of walis.
By Mr. Wilkinson-In witness's opinion the probabilities were that but for the extraordinary character of the wind and rain this year, the collapse would not have happened.